THE SUNBORN GREGORY BENFORD ASPECT NEW YORK BOSTON This book is a work of fiction. Names, characters, places, and incidents are the product of the author's imagination or are used fictitiously. Any resemblance to actual events, locales, or persons, living or dead, is coincidental. Copyright © 2005 by Abbenford Associates All rights reserved. Aspect Warner Books Time Warner Book Group 1271 Avenue of the Americas, New York, NY 10020 Visit our Web site at www.twbookmark.com. The Aspect name and logo are registered trademarks of Warner Books. Printed in the United States of America First Printing: March 2005 10 987654321 ISBN: 0-466-53058-1 LCCN: 2004114834 To Robert Forward, Charles Sheffield, and Hal Clement They showed a scrupulous respect for the culture, methods, and findings of science, no matter where these led. PART I RAW MARS The world will never starve for wonders; but only for want of wonder. —Gilbert Keith Chesterton The sun's seethe broke upward, flaring into a fountain of fire. A colossal magnetic arch trembled, rubbery and snaking with scorching energies. At its very top the lacy magnetic fibers ruptured. Virulent plasma poured forth, fleeing the star in furious jets. The angry spout curled and spat, thundering into the vacuum, spreading, whipping into fresh filaments. White-hot, it splashed and spun. Yet from this violence came structure. Crackling traceries writhed and coiled together. Bright strands peeled from the outrushing flow. Howling ferocity fought, expanded, and then cooled as the billowing plume rose. Lacy arrays came and went as magnetic forces struggled against the blaring heat of plasma now unleashed. Here and there, fields weaved and knotted. Order arose in the sprawling, swelling teardrop. Internal wrath dimmed. The plasma gout sped outward from the parent star, rushing into the realm of planets, bringing stormy funnels, wriggling and fighting. A red world lay in its path, unshielded, its ancient rock cloaked only by a thin film of gas. Yet life clung there. Frothing with great, seething energies, the tempest roared toward it. 1 FIRM, FRIENDLY, POSITIVE JULIA TURNED HER BEST SIDE toward the camera, a three-quarters shot, and spread her arms. Okay, maybe a bit theatrical, but she had the backdrop for it. "Welcome to Earth on Mars!" She always opened firm, friendly, positive. She swept an arm around, taking in the stubby trees with their odd purple-green leaves, the raked mounds barely sprouting brownish green patches, and above it all, the shiny curve of the dome, a hundred meters high. Beyond the dome's ultraviolet screening hung the dark bowl of space. The somber cap was always there, reminding them of how little atmosphere shielded them. "We showed you the inflation of the big dome a month ago, the planting of trees right after—now we have grass." Not any breed of grass you've ever seen before, though; it's a genetically modified plant more like a dwarf bamboo, and technically bamboo is a grass, just a really stiff one, so... "It'll be a while before we can play football on it, true. We're pretty sure nothing like grass ever grew on the surface of ancient Mars, even back in the warm and wet period. So this prickly little fuzz"—she stooped to stroke it—"is a first. It'll help along the big job that the microbes are doing down in the ground already—breaking up the regolith, making it into real soil." Was she sounding strained already? It was getting harder to strike the right level of enthusiasm in her weekly broadcast to Earthside. She could barely remember the days, decades before, when she had broadcast several times a day, sometimes from this same spot. But then, they had been breaking new ground nearly every day. And betting pools on Earth gave new odds every time they went out in the rover, for whether they'd come back alive. Usually about fifty-fifty. The good ol' days. She smiled, strolling to her right as Viktor panned the camera. She had to remember her marks and turns, and to keep out of camera view the crowd of camp staff watching nearby. Viktor called, "Cut, got sun reflecting in the lens." "Whew! Good. Let me memorize a few lines..." She was glad for the break. It was getting harder to sound perky. The Consortium people had been grousing about that lately. But then, they had done so periodically, over the two decades she and Viktor had been doing their little shows. Media mavens had some respect for The Mars Couple (the title of the Broadway musical about them), but the long shadow of the Consortium, which had backed the 2018 First Landing (the movie title), wanted to keep them on the air for the worldwide subscriber base—and always pumping the numbers higher, of course. Axelrod, still the head of the Consortium, The Man Who Sold Mars (the miniseries title), and now probably the wealthiest man in the solar system, played diplomat between them and the execs Earthside. Exploration? Discovery? Yes, they still got to do some. But a safari that turned up nothing new—like the Olympus Mons fiasco {Climb the Solar System's Highest Mountain!)—could drive down Consortium shares, send heads rolling at high corporate levels, and make headlines. So she and Viktor tried not to think too much about the eternal media issues. It never really helped. Viktor was fiddling, changing camera angle, and here came Andy Lang, trotting over with his studied grin. "Julia, got an idea for a last shot." "What is it?" She looked beyond him and saw the two arm wings Andy had brought from Earth the year before, bright blue monolayer on a carbon strut. "Oh—well, look, we've done your flying stunt three times already." "I'm thinking just a closing shot." He gestured up to the top of the dome, over a hundred meters above. "I come off the top platform, swing around the eucalyptus clump, into Viktor's field of view—after you do your last line." "Ummm." She had to admit they had no good finishing image, and Earthside was always carping about that. "You can do it?" "Been practicing. I've got the timing down." He was a big, muscular guy, an engineering wizard who had improved their geothermal system enormously. And a looker. Axelrod made sure to send them lookers. After all, thousands volunteered to work here every year. Why take the ugly ones when the worldwide audience liked eye candy? Julia looked up at the ledge platform near the dome peak. Andy's earlier flights had gone around the dome's outer curve, pleasantly graceful. The eucalyptus stand at the dome's center was her pet project. She insisted on some blue gum trees from her Australian home, the forests north of Adelaide. Earthside dutifully responded with a funded contest among plant biologists to find a eucalyptus that could withstand the sleeting ultraviolet here. Of course, the dome helped a lot; chemists had developed a miracle polymer that could billow into a broad dome, holding in nearly a full Earth atmosphere, and yet also subtract a lot of the UV from sunlight—all without editing away the middle spectrum needed for plant growth. The blue gums were a darker hue, but they grew rapidly in the Martian regolith. Of course she had to prepare the soil, in joyful days spent spading in the humus they had processed from their own wastes. The French called it eau de fumier, spirit of manure, and chronicled every centimeter of blue gum growth. She'd sprouted the seeds and nurtured the tiny seedlings fiercely. Once planted, their white flanks had grown astonishingly fast. Their leaves hung down, minimizing their exposure to the residual hard ultraviolet that got through the dome's filtering skin. But their trunks were spindly, with odd limbs sticking out like awkward elbows—yet more evidence that bringing life to Mars was not going to be easy. She considered. Andy was a media hit with the ladies Earthside, if perhaps a bit of a camera hog. She had been giving him all the airtime he wanted lately, glad to off-load the work. "Okay, get on up there." She checked the timing with Viktor while Andy shimmied up the climbing rope to the peak of the dome and its platform, the big arm wings strapped to his back making him look like a gigantic moth. They moved location so that Andy would be shielded from Viktor's view until he came around the clump of whitebark eucalyptus trunks as Viktor panned upward from her concluding shot. In a few minutes more they were ready to go. Julia wondered if she could ease out of this job altogether, letting Andy the Hunk take most of it. She made a mental note to tactfully broach the subject with Axelrod. "Positions!" Viktor called. Andy nodded from the platform, wings in place. "On," Viktor said. Without thinking about it Julia hit the same marker where she had left off. "You can't imagine how thrilling it is to walk on Martian grass, without a space suit, breathing air that smells ... well, I won't lie, still pretty dusty. But better, yes. To think that we used to test the rocks here for signs of water deposition! Once the raw frontier, now a park. Progress." Of course, the hard part was turning regolith rocks and sand into topsoil, but that's booooring, yes. Earthside had developed some fierce strains of bacteria that could break down all comers—old running shoes, hardbound books, insulation, packing buffers—into rich black loam almost as you watched. She ducked as a white shape hurtled by, narrowly missing her head. "Chicken alert!" she said lightly, gesturing toward it with her head. It squawked and flapped, turning like a feathered blimp with wings. "Who would have thought chickens could have so much fun up here, in the low gravity? They find it far easier to fly here than on Earth. Of course, we brought them here so we could have fresh eggs, and they do lay, so we predicted that part correctly. But we don't always know everything that's going to happen in a biological experiment. This is the Mars version of the chicken and egg problem." Viktor smiled dutifully; they'd shared this little joke before. The Earthside producer would more probably wince. Okay, back to the script. She waved a hand to her right, and Viktor followed the gesture with the camera, bringing in the view of the slopes and hills in the distance, beyond the green lances of the eucalyptus limbs. The slopes were still rusty red in the afternoon light, far beyond the dome that sloped down to its curved tie-down wall eighty meters away. They stood out nicely with the green eucalyptus foreground. The other trees—ranging from drought- and cold-resistant shrubs from Tasmania to hardy high-altitude species—almost made a convincing forest. The "grass" was really a mixture of mosses, lichens, and small tundra species, too. A big favorite of the staff was "vegetable sheep," soft, pale clumps from New Zealand's high country. Convincing to the visual audience—a golf course on Mars!—but also able to survive a cold Martian night and even a sudden pressure drop. The toughest stuff from Earth, made still more rugged with bioengineering. Axelrod had insisted on the visuals. Make it look Earthy, yes. She had worked for years to make the inflated domes support life, and there was still plenty to do. Making the raw regolith swarm with microbes to build soil, coaxing lichens onto the boulders used to help anchor the dome floors in place, being sure the roots of the first shrubs could survive the cold and prickly alkaline dirt... Years, yes, grubbing and figuring and trying everything she could muster. For a beginning. Pay attention! You're on-Camera, and Viktor hates to reshoot. "Ah, one of my faves..." She altered course to pass by a baobab— a tall, fat, tubular tree from Western Australia, with only a few thin, spidery limbs sprouting from its top, like a nearly bald man. Early settlers had used them for food storage, take shelter, even jail cells. On Mars they grew spectacularly fast, like eucalyptus, and nobody knew why. Aussie plants generally did better here, from the early greenhouse days of the first landing onward. Maybe, the biologist in her said, this came from the low-energy biology of Australia. The continent had skated across the Pacific, its mountains getting worn down, minerals depleted, rainfall lessening, and life had been forced to adapt. A hundred million years of life getting by with less and less ... much like Mars. "For those of you who've loyally stuck with us through these— wow!—twenty-two years, I say thanks. Sometimes I think that this is all a dream, and days like this prove it. Grass on Mars! Or—" She grinned, tilting her head up a bit to let the filtered sunlight play on her still-dark hair, using the only line she had prepared for this 'cast. "Another way to say it, I started out with nothing and still have most of it left. Out there—in wild Mars." Not that this little patch is so domesticated. It's how we find out if raw regolith can become true soil, and what will grow well here. "Already, there are environmental groups trying to preserve original, ancient Mars from us invaders." She chuckled. "If Mars were just bare stone and dust, I'd laugh—I never did believe that rocks have rights. But since there's life here, they have a point." This was just editorial patter, of course, while Viktor followed her on the walk toward the fountain. It tinkled and splashed in the foreground while she approached, Viktor shooting from behind her, so the camera looked through the trees, on through the clear dome walls to the dusty red landscape beyond. "I like to gaze out, so that I can imagine what Mars was like in its early days, a hospitable planet." She turned, spread her hands in self-mockery. "Okay, we now know from fossils that there were no really big trees—nothing larger than a bush, in fact. But I can dream..." She smiled and tried not to make it look calculated. After a quarter century of peering into camera snouts she had some media savvy. Still, she and Viktor thought in terms of, If we do this, people will like it. That had been a steadier guide through the decades than taking the advice about exploring Mars from the Earthside media execs of the Consortium, whose sole idea was, If we do this, we'll maximize our global audience share, get ideas for new product lines, and/or optimize near-term profitability. She paused beside the splashing fountain. She plucked up a cup they had planted there, and drank from it. "On Earth you can drink all the water you want and leave the tap on between cupfuls. Here, nobody does." She smiled and walked on. "You've seen this before, but imagine if it were the only fountain you'd seen in a quarter century. That's why I come here to read, meditate, think. That—and our newest wonder..." Let them wait. She had learned that trick early on. Mars couldn't be chopped up into five-second "image bites" and leave any lasting impression. She circled around the constant-cam that fed a view to Earthside for the market that wanted to have the Martian day as a wall or window in their homes. She knew this view sold especially well in the cramped rooms of China and India. It was a solid but subtle advertisement. Crowded? Here's a whole world, only a few dozen people on it—well, actually, about ten dozen—and it has the same land area as Earth. A different world entirely. Things were different, all right. The dome was great, the biggest of several, a full 150 meters tall. It would have been far more useful in the first years, when they still lived in apartment-sized habs. Now her pressure suit was supple, moving fluidly over her body as she walked and stooped. The first expedition suits were the best of their era, but they still made you as flexible as a barely oiled Tin Man, as dextrous as a bear in mittens. The old helmets misted over unless you remembered to swab the inside with ordinary dish soap. And the catheters had always been irksome, especially for women; now they fit beautifully. Outside, the wind whistled softly around the dome walls. Another reason she enjoyed the big dome—the sighing winds. Sounds didn't carry well in Mars' thin atmosphere, and the habs were so insulated they were cut off from any outdoor noise. The grass ended, and she crunched over slightly processed regolith. Lichens could break the rock down, but they took time—lots of it. So they'd taken shortcuts to make an ersatz soil. They mixed Martian dust and small gravel-sized rock bits with a lot of their organic waste, spaded in over decades—everything from kitchen leftovers to slightly cleaned excrement. Add compost-starter bacteria, keep moist, and wait. And hope. Microbes liked free carbon, using it with water to frame elaborate molecules. She and Viktor had doled it out for years under the first, small dome before even trying to grow anything. The Book of Genesis got it all done in six days, but mere humans took longer. She hit the marker they had laid out—a rock—and turned, pointing off-camera. "And now—ta'daah!—we have a surprise. The first Martian swimming pool." Okay, no swimming pools in Genesis—but it's a step. "I'm going for my first swim—now." She shucked off her blue jumpsuit to reveal a red bikini. Her arms and legs were muscular, breasts midsize, skin pale, not too many wrinkles. Not really a babe, no, but she still got mash notes from middle-aged guys, somehow leaking through the e-mail filters. Hey, we're looking for market share here! She grinned, turned, and dove into the lapping clear water. Surfaced, gasped—she wasn't faking, this really was her first swim in a quarter century—and laughed with sheer pleasure (not in the script). Went into a breaststroke, feeling the tug and flex of muscle, and something inexpressible and simple burst in her. Fun, yes—not nearly enough fun on Mars. Or water. They had moved from the original base camp about eighteen years before. Once Earthside had shipped enough gear to build a real water-retrieval system, and a big nuke generator to run it, there seemed no point in not moving the hab and other structures—mostly light and portable—to the ice hills. Mars was in some ways an upside-down world. On Earth one would look for water in the low spots, stream channels. Here in Gusev water lay waiting in the hilly hummocks, termed by geologists "pingos." When water froze beneath blown dust, it thrust up as it expanded, making low hills of a few hundred meters. She recalled how Marc and Raoul had found the first ice, their drill bit steaming as ice sublimed into fog. Now Marc was a big vid star and Raoul ran Axelrod's solar energy grid on the moon. Time... She stopped at the pool edge, flipped out, and sprang to her feet— thanks, 0.38 g! "The first swim on Mars, and you saw it." Planned this shot a year ago, when I ordered the bikini. She donned a blue terry-cloth bathrobe; the dryness made the air feel decidedly chilly. "In case you're wondering, swimming doesn't feel any different here. That's because the water you displace makes you float—we're mostly made of water, so the effect compensates. It doesn't matter much what the local gravity is." Okay, slipped in some science while their guard was down. "Behind all this is our improved water-harvesting system." She pointed out the dome walls, where pipes stretched away toward a squat inflated building. "Robotic, nuclear-powered. It warms up the giant ice sheets below us, pumps water to the surface. Took nine years to build— whoosh! Thank you, engineers." What did the water mean? She envisioned life on a tiny fraction of Mars with plentiful water—no longer a cold, dusty desert. Under a pressurized dome the greenhouse effect raised the temperature to something livable. Link domes, blow up bigger ones, and you have a colony. They could grow crops big-time. Red Kansas... A gout of steam hissed from a release value, wreathing her in a moist, rotten-egg smell. Andy had put the finishing touches on the deep thermal system, spreading the upwelling steam and hot water into a pipe system two meters below the dome floor. Their nuke generators ran the system, but most of the energy came for free from the magma lode kilometers below. Once the geologists—"areologists" when on Mars, the purists said—had drilled clean through the pingos and reached the magma, the upwelling heat melted the ice layers. Ducted upward, it made possible the eight domes they now ran, rich in moist air. Soon they would start linking them all. She smiled as she thought about strolling along treelined walkways from dome to dome, across windblown ripe wheat fields, no helmet or suit. Birds warbling, rabbits scurrying in the bushes. In the first years their diet had been vegetarian. It made sense to eat plant protein directly, rather than lose 90 percent of the energy by passing it through an animal first. But from the first four rabbits shipped out they now had hundreds, and relished dinner on "meat nights." They'd have one tonight, after this media show. "So that's it—life on Mars gets a bit better. We're still spending most of our research effort on the Marsmat—the biggest conceptual problem in biology, we think. We just got a new crew to help. And pretty soon, on the big nuke rocket due in a week, we'll get a lot more gear and supplies. Onward!" She grinned, waved—and Viktor called, "Is done." She had waited long enough. She shucked off the bathrobe and tossed the wireless mike on top of the heap. "Am still running." "Check it for editing," she said quickly. "I'm going to splash." She dove into the pool again. Grinning, Viktor caught it in slow-mo. Julia rolled over onto her back and took a few luxurious strokes. She caught Andy's kick off the platform and watched him swoop gracefully around the dome. It was still a bit of a thrill to see. They kept the dome at high pressure to support it, which added more lift for Andy. He kept his wings canted against the thermals that rose from the warm floor, camera-savvy, grinning relentlessly. Even with the lower gravity and higher air density, Viktor and Julia had been skeptical that it could work. But Axelrod and the Consortium Board had loved the idea, seeing tourism as a long-term potential market. And Andy did look great, obviously having a lot of fun, his handsome legs forming a neat line as he arced above. He rotated his arms, mimicking the motion birds make in flight, pumping thrust into his orbit. His turn sharpened into a smaller circle, coming swiftly around the steepled bulk of the big eucalyptus. His wings pitched to drive him inward, and wind rippled his hair. Julia watched Viktor follow the accelerating curve with the camera, bright wings sharp against the dark sky. Good stuff. But he was cutting it close to the tree, still far up its slope. The Consortium Board had chosen Andy both for his engineering skills and for this grinning, show-off personality, just the thing to perk up their audience numbers. His T-shirt flapped, and he turned in closer still. She lost sight of him behind the eucalyptus, and when he came within view again, there seemed to be no separation at all between his body and the tree. Ahead of him a limb stuck out a bit farther than the rest. He saw it and turned his right wing to push out, away, and the wing hit the limb. For an instant it looked as though he would bank down and away from the glancing brush. But the wing caught on the branch. It ripped, showing light where the monolayer split away from the brace. Impact united with the change in flow patterns around his body. The thin line of light grew and seemed to turn Andy's body on a pivot, spinning him. The eucalyptus wrenched sideways. It was thin, and the collision jerked. He fought to bring the wing into a plane with his left arm, but the pitch was too much. Julia gasped as his right arm frantically pumped for leverage it did not have. The moment froze, slowed—and then he was tumbling in air, away from the tree, falling, gathering speed. The tree toppled, too. In the low gravity the plunge seemed to take long moments. All the way down he fought to get air under his remaining wing. The right wing flapped and rattled and kept him off-kilter. His efforts brought his head down, and when he hit in the rocks near the pool, the skull struck first. The smack was horrible. She cried out in the silence. Andy had not uttered a sound on the way down. 2 BOOT HILL The traditional dune buggy with the shrouded body crawled slowly up the small hill. Footprints had made the entire area smooth, and the cortege followed a well-worn path. The stone cairn, which they'd erected twenty years ago when the first mission landed, had had many visitors. Also by tradition, the burial would be late in the day. Boot Hill looked out over the red and pink and brown wilderness of Mars. With the domes of the colony in the distance the mourners were reminded of the strangeness of their new world and surrounded with the beauty of a Mars sunset. It was a fitting send-off to a fellow explorer and served somehow to lessen their grief. Julia well remembered that small party of five who'd established the graveyard with the mounds for Lee Chen and Gerda Braun. Today there were twelve mounds and ten times as many mourners. Every time they did this the line was longer. We lost Alexev in a fall, Sheila Cabbot in an electrical failure. And, of course, two aerobraking tragedies. Andy is the thirteenth. Over the years they'd added far more graves than Julia had ever wanted to see, and had to expand the original boundary circle of rocks several times. None lost to disease yet. All accidents. She reached the top of the hill and scanned back along the line of suited figures trudging up the rise. The newcomers were easy to pick out, stumbling slightly in an uncertain rhythm. The efficient "Mars gait" took a bit of time to master. Also, the harsh reality of Mars was likely hitting them full force for the first time. The younger ones tended to babble in times of stress. The chatter in the suit mikes was unsettling; she switched hers off. Someone Julia didn't immediately recognize was scanning a small vid around the scene. Most everything they did was recorded; she should have been used to it by now. But she still chafed under the watchful lens eyes. It seemed like an intrusion here, just to make a fleeting news item Earthside. But then, Andy had loved the spotlight. He wouldn't mind. She looked carefully at the figure holding the vid. Still no recognition. We've really grown; I used to know everyone instantly, just by gait and size. Usually without looking at their suit markings. Hope this guy is new, and not someone I've forgotten. Viktor jogged her arm, and she turned back to the ceremony. She leaned over and touched her helmet to his. "Who's the guy with the vid? Is he new?" "Didier Rabette. From machine shop. Here two years already." One of the geologists was a lay preacher, and she'd volunteered to officiate. That, too, was new; they were really beginning to specialize. Progress. The ceremony was brief but effective. Julia thought suddenly about navy sea burials. Regrets, but the mission must continue. She let the bulk of the crowd leave, stung anew by the suddenness of death. She never got used to it: how someone you'd just talked to, or someone who had always been there, was now gone. She still held internal conversations with her parents, although both were gone. Her father had slowly declined from one of the newly emerging killer viral diseases, the zoonosis class that migrated from animals to humans, fresh out of the African cauldron. It was really no surprise when he died. But her mother's death had been sudden: a brief respiratory illness, one of the "new" flus that roamed the crowded Earth, and she was gone in less than a week. From "doing fine" to "done for" in just over twenty-four hours, actually. Julia realized that even if she'd not been 50 million miles away, she likely would not have rushed to her mother's bedside, because the course of the disease had been so ambiguous, the decline so sudden. At least, she thought ruefully, it helped assuage her guilt a little. But now Andy—plucked from them in a heartbeat. As a biologist she understood intellectually that evolution requires death; if all the original forms were still around, there would be no room for the new ones. But emotionally it was very hard to understand. Afterward, on the way down, she was surprised by how large the colony looked. In the gathering dark, lights twinkled in the distance, stirred by the dusty breeze. "Mars City" was beginning to take shape. 3 THE MARS EFFECT "We MUST meet WITH the new ones," Viktor said crisply the next morning over breakfast in the compact cafeteria. "First thing today." They were sitting at their usual table, and nobody in the crew sat with them, by tradition. They were the founders, after all. Julia sometimes waved some of them over, but usually she and Viktor wanted privacy. It reminded them of the early years, when the two of them had had Mars to themselves. No one within 50 million miles. They'd staved off the lurking fears of abandonment and ever-present danger by creating their own private reality. By focusing closely they became the whole world to each other. As they had come into the cafeteria, the audio switched to some gospel music, an unusual choice for her, but it fitted her current mood. "Trouble of This World" by Bill Landford rang gracefully amid the clatter of breakfast. In the two days since Andy's death a numb, gray pall had descended. Julia and Viktor had taken full responsibility, and meant it. The Consortium Board, meeting in emergency session, had rejected that explanation. Andy had flown inside the dome over a hundred times. Hang-glider enthusiasts around the world had endlessly rerun the pictures of Andy's tight glide, and they emerged with a consensus: he had cut the margin too fine. Andy had never flown that tight a circle around the eucalyptus before. He had simply misjudged. The vast Martian subscription audience felt the same. There had been the usual abrasive commentary, asking whether Julia and Viktor had simply lost their judgment from the long years of running the Gusev Mars Outpost, but that was so expected that nobody paid attention. Not that any of it helped Julia and Viktor. They did feel responsible, and no media mavens could change that. "Trouble of This World" mournfully underlined their mood. Julia sipped coffee and let her doubts well up within. It was better to let the feelings wash over her and live in them fully, knowing they would pass. They had found long before that music knitted together the small community here, made it seem less isolated from humanity. The occasional disputes over what to play—the opera buffs thought Wagner for breakfast was fine—were worth it. Today it certainly helped to hear a chorus singing quiet spirituals over the breakfast clatter. She said nothing and gazed out the big window. Their table commanded its view, taking in the big new dome to the left, and beyond it the dozens of lesser domes, habs, Quonset huts and labs and depots. All with sandbags atop to shield against the solar wind and cosmic rays that sleeted down here eternally. Tracks crosshatched the whole area, and color-coded, suited figures moved everywhere in pressure suits. Ugly, she had to admit. Immediately she looked beyond the bustling colony. There lay beauty. The roll of dark hills across the crater floor blended into the bright talus slopes that swept up into the craggy crater walls. A kilometer up, the rocky edges of the crater blended into a pink-brown sky that quickly faded into black. She never quite got used to that sky—blacker than ebony and holding a sun hard and bright against the dim backdrop of stars. Raw Mars, still out there. She got homesick, of course, often triggered by the similar desert landscapes here. On summers in her girlhood her family had returned to a small town of one thousand in The Mallee region of north Victoria. There were unending games with the kids of the town, flitting among the blue gum trees along the shaded billabongs. The dry heat had seemed to swarm up into her nostrils like a friend, welcoming her back into carefree summer. There was cracker night, with fireworks shooting off in backyards and the town square. The dads drank XXXX beer and lit fuses with glee. Dogs hid whimpering under beds, and crowds oohed at bursting stars. The best part was the scary moments when something went wrong. Once her father somehow set fire to an old dunny in the yard, and the heavy stench of old dung came rising out of the pit when they hosed it down. Her grandest adventure, carried out against the fearsome warnings of the boys, had been the Great Ascent of the grain silo. She'd waited until nobody was about in the late afternoon, and the door stood ajar at the base of the empty, echoing 120-foot concrete tower. There was only pale wheat dust inside, awaiting the harvest, but as she went up the narrow ladder with no rail, the dust made the rungs slippery. When she reached the first landing, her right foot slipped on the slick dust and she fell to one knee, snatching at the step and barely holding on. That deserved a pause, but the light was fading inside, so she started up the next ladder, and without pause the next. The great cylinder above seemed infinite, and the six ladders took her at last to a narrow platform that capped the roof. She peered out across the chessboard fields and to the east sighted the next silo, gleaming crimson in the sunset. To the west was the next silo, and she imagined them marching all the way to the vast Nullarbor, the null-arbor land of no trees that stretched a full thousand miles. Then she looked down. Her younger brother, Bill, waved up at her. He must have followed when she sneaked away. He was right below, staring up. He made his ghoul face, eyes wild. She spat a big gob—her mouth was dusty—and watched it dwindle away, skating on the breeze. He danced away, laughing. She was amazed, in her last long glance about, at how her feeling for the land changed just by getting above it. For the first time she sensed herself as a tiny creature on a great turning sphere beneath a forgiving star. Back inside, on the way down, she slipped again and hung on with one hand. Somehow, though her heart thumped, she did not feel fear. When she got home, her brother told on her and they both got a spanking, her for the climbing and he for telling. But worth it, oh yes... Back to business. "Sorry, you were saying..." "We must meet with new people," Viktor said. She sighed. "I suppose so." He grasped her hand and squeezed. "Andy would not want the work to stop." "Um. Earthside wanted—" "Forget Earth." "I've got a desk of work to do—" "Will wait." She recalled the schedule. Always the schedule. "Look, we've only got a day left before—" "I know, excursion." His face split with the familiar warm grin. "We've got descent scheduled at that new vent, site C4." "And it's taken us a month to arrange it." "To overcome Consortium rules, you mean." "It's like they don't want us—you and me—to ever go out again." She slurped up some coffee without taking her eyes from the view. His magic was working. She was getting back into life. He shrugged, and his slight smile crinkled at the edges, joining the spidery lines that now laced down from his eyes. "We are too famous to lose." "So we have to sit inside forever?" Viktor's slightly lifted eyebrows reminded her that he knew well the edge in her voice. She could see him carefully look into her eyes and use the old tricks. "We not let them do this." "They can't ship us back." After decades at 0.38 g, returning to Earth would be agony. Or maybe worse. Nobody knew the long-term effects of returning, whether the stress to the body could ever be compensated. Viktor nodded. "Is advantage, in a way. We can't go home, so we sit here." She snorted. "Museum exhibits." "Axelrod sent message, said to talk to the new ones right away. Especially this"—he consulted a scribbled note—"Praknor person." "Come on, he can't set schedules from the moon; we got away from that years ago." "Said was important," Viktor went on stolidly, his hedgehog maneuver she knew so well. "We had the usual welcoming ceremony, made them Martians, the water ritual, the reception—" "I think is mostly political"—for Viktor this was the ultimate criticism—"and we must." "Let them look around while we're gone. It'll save time if they have a feel for—" "Must." "Um." "Must." Viktor was right, of course. She remembered the videographer she hadn't recognized at the funeral; was she out of touch? So right after breakfast they met with one Sandra Praknor—efficient, neat, intent, with a hawklike look to her. She was a science manager, her dossier said, a field that had risen to prominence recently. Research had gotten so complex back Earthside that a whole layer had grown to mediate between the actual researchers and the resources they needed—computational, simulations, data analysis, and most of all the artificial design intelligences. Science manager? She was already overseeing the colony's extensive research program. It made sense for that job to be on-site rather than at the Consortium. Paperwork was boring, even though it was all digital and Earthside-AI-assisted, but overall, the job was enjoyable; it let her vicariously experience all the studies going on, folded in with the huge Earthside effort. Even if they didn't get to go on all the expeditions themselves, she thought ruefully. Viktor was right: there was increasing resistance Earthside and on the moon to their engaging in "risky" behavior. She had sardonically observed, reading the dossier, "Praknor has a 'cross-science degree'—what's that?" In person it was even harder to tell what areas Praknor knew. The Consortium had hired her away from a major lab, and she had a crisp, executive style. She opened with remarks about Andy, condolences, and hopes that the death did not compromise the future of exploration. Julia carefully put aside her emotions. She focused on Praknor's face, trying to read it but getting nowhere. Midlength dark hair, rather mannishly cut; the expression in the eyes too solid for a younger person; an open face that told nothing. As Julia opened her mouth to speak, Praknor threw her hair back. It flounced in the light gravity, reminding Julia of all the irritating blondes she had competed with in school. Julia's hair didn't work well that way, too fine, and the gesture alone still set her teeth on edge. She made herself focus on Praknor's manner, trying to read it. In her previous job this woman must have been used to ordering the scientists around. She had a certain managerial blandness. No tics, no nervousness; just resolve. She wondered if Praknor could be caught off-guard. And where was her enthusiasm? "We've had twelve deaths," Viktor said simply. "That did not slow us." Praknor nodded and then went on and made the expected complimentary remarks. She mentioned how she had as a teenager set out to go into exobiology, a field that came of age with their discovery of the Marsmat. "I hope that will help me improve the program here," she concluded. Viktor said warily, "Improve how?" She gave them a thin smile. "Chairman Axelrod hired me personally. He wants me to impress upon you the necessity to find products for export. We of the Consortium cannot depend upon our product lines and the research investment of ISA to sustain us here indefinitely." To Julia this was transparently a prepared speech, and Viktor's slow blink told her that he thought so, too. "Such as?" Praknor smiled again, or rather the mouth did; the eyes stayed the same. "Your Marsmat foods idea—well, it hasn't panned out." "Does not taste good," Viktor said. "And was Earthside idea, not ours." "I sent those samples back for scientific purposes," Julia said evenly. "Not for Axelrod to start a product line." "Well, I wasn't with the Consortium then," Praknor said, opening her laptop slate and consulting it. She went into another carefully phrased opening statement about the need for all levels of the Consortium to cooperate in developing new "revenue avenues." At this point Julia tuned her out. Mars had some resources, but few that were worth shipping to Earth. The first hit was some "Mars jewels" they found in the volcanic layers dotted around Gusev Crater. Pale, with mysterious violet motes embedded in milky teardrops, they commanded huge prices for a few seasons. Some flecked sulfur-laden stones later became fashionable. The perennial sellers were the "blueberries" the '04 rovers found, just hematite—but Martian hematite, so worth a thousand bucks a gram. Still, novelty only lasts so long. Viktor had thought of another sideline, one that Axelrod liked especially. He had systematically rounded up all the parachutes that had slowed the dozens of landers, rovers, and provisions carriers that had landed in Gusev over several decades, ever since the first one at Christmas, 2003. The silky parachutes were seared by ultraviolet and solar wind particles, dirtied with red dust—and made grand T-shirts for the fashionistas on Earth. Later, Axelrod cut a deal with several governments and made an even greater profit by returning to Earth the original rovers and landers still standing on the surface. These went to museums and private collectors. "Think of it as being able to buy the Niña, the Pinta, or the Santa María," went one of the glossy upscale brochures. Some lesser billionaires had bought heat shields and other pieces discarded in the era of automated exploration. Apparently they made handsome "found techno-art" displays in the entrance foyers of big corporations. Then Axelrod sold off the Original Four's actual pressure suits, their houseware ("Dine as they did!"), even their worn-out flight jackets, T-shirts, and jeans. Raoul had reported in a letter that at a cocktail party reception a man had come up to him and proudly pointed out that he was wearing the very loafers that Raoul had used in the hab. They did not go well with the tux he was wearing, but the man didn't seem to care. Julia kept her distance as much as possible. At first she had been cheerful about the whole commercialization thing, but Axelrod's relentless marketing wore her down. Even hundreds of millions of kilometers away, it got to her. She clearly recalled unwrapping supply drone packages and finding plastic supermuscled action figures that bore caricatures of her and Viktor's faces. Then there was the movie, miscast and scripted by writers who mostly knew four-letter words but no science. The animation series had been no better. Julia recalled all that in a flash, studying Praknor's assured manner, and wondered what would come next. "The jewels are still a steady item, but my main effort will be to supervise more studies on the..." Here Praknor slowed, eyes flicking from Viktor to her slate, and Julia knew what she was going to say. "Mars Effect," Julia finished for her. "Uh, yes, I—" "Does not exist," Viktor said. "Our data—" "Comes from good healthy lifestyle," Viktor said, following the line they had agreed on. "Plenty work, exercise, light diet, clean air. Also, we were picked because of good health and physical condition. Plus smarts." Praknor said, "For years there was excess hydrogen sulfide in the agro domes where you two worked." Viktor dismissed this with a wave of his hand. "All filtered out now." "Before its effects were properly studied," Praknor said exactly, "in coordinated trials." "Stunk, was its effect," Viktor said. "You're not suggesting that hydrogen sulfide confers a health benefit, are you?" Julia asked. Her first experience of high school chemistry had been an experiment that made those rotten-egg fumes. She'd laundered her clothes every day, in the first dome years, to get the stink out. "Something must explain your extraordinary longevity, as confirmed again in last year's Maxfield Index study." "That index has a huge variance," Julia said to buy time. "It is universally recognized as a reliable indicator of expected longevity," Praknor said primly. "You two have consistently scored very high in"—Praknor began ticking off items on her fingers—"reflexes, physiochem, metabolic rate, endurance, comprehension speed, pre-cancer indicators—" "All normalized to Earth," Viktor said. "And for large samples. Here is sample of two." "Mr. Axelrod feels it is a powerful indicator. So do a lot of other specialists. Your bodies are not showing the sag and weakening of the general population—" "Lower gravity," Julia said. "—and I'm sure you aren't dyeing your hair." To their puzzled looks she said, "No gray. That certainly isn't due to mechanical effects." "Genetics," said Julia. "In my family we don't get gray until we're in our eighties." She turned to Viktor. "What about you?" He shrugged, a carefully blank expression on his face. Undaunted, Praknor showed them on her slate a complex, three-dimensional data contour map. It was a tall hill, color-coded so that at the crown a yellow-green spot marked out the Mars sample range. "You two, exposed to higher radiation doses and ultraviolet for over two decades, are doing better than 99 percent of the global population." "Most of that population is starving in Asia," Viktor said conversationally. "Comparison with the Euros shows the same," Praknor shot back. "Too rich diet, too little exercise," Viktor countered mildly. "Look," Julia said, equally mildly, "Axelrod has been pushing this idea hard for, what, six, eight years? So he can sell berths and luxury suites in his Mars-Orb." "Sales prompted by your own results," Praknor said, visibly not letting herself get roused. "Starting with the tests eleven years ago." They had been shrugging off this issue for years. It had seemed just another of the Earthside fads that ran for months and then faded. But now in Praknor's firmly set jaw Julia could see trouble. The worst visitors to Mars by far had been the Med Study Team, which had arrived all enthused with testing and "optimizing" the physical conditioning effects on Mars. This was in the days when Earthside still thought 0.38 g was bound to cause physiological damage—a holdover from the NASA programs that had endlessly obsessed over zero g, without ever doing centrifugal-gravity tests. The Med Study Team brought with them stationary bikes, with which they hosted "spinning" competitions, and talked up how much they were all going to learn about the Mars Effect. That awful two years climaxed in a group "spinning climb" called Mt. Everest Week. Everybody in base (a lucky few were out on an extended foray for samples, and spared) gathered in the dining area, which sported Tibetan prayer flags and burning candles. (The effrontery of burning anything on an oxygen-starved world hadn't occurred to the Med Study Team, of course.) The big screen showed the real Everest views, tracing their imaginary progress with little flags on an inset map. They all pedaled furiously, sweating, spinning, and the Med Study Team made measurements. They were supposed to be making an internal journey, while literally going nowhere. A team member dumped dry ice into buckets of water to simulate Himalayan mists as the team leader announced after four hours that they were "ascending" the peak. Viktor got there first. Everyone in the team took this as clear proof of the Mars Effect. Julia took it as adaptation, no more. But with Viktor's victory she had enough clout to do something. The team wanted to stay, but she and Viktor used their immense leverage in Earthside media to leak their irritation. They said they could study any Mars Effect on their own, thank you. The Consortium stalled only a bit. The Med Study Team went back to Earth on the next boost, and she had never been so glad to see the back of anyone in her life. The Mars Effect talk had surfaced repeatedly after that. True enough, the physical exams showed that she and Viktor were not losing their resilience. The aging Earthside population in the advanced nations had driven a huge industry devoted to prolonging life spans, and their diagnostics now had great predictive value. The battery of tests could warn aging managers when to retire, how to optimize their remaining years, even what genetic markers foretold about their probable death modes. So the "Mars Effect" had emerged as she and Viktor stood up well in the tests, capturing yet more media attention. Axelrod had seen a profit awaiting and began his orbital retirement resorts. After all, the man had built himself into a multi-billionaire from media empires and real estate. Without him the first Mars expedition would probably never have happened. After NASA's big blowup on the Canaveral pad Axelrod had seen opportunity where others saw only disaster. He had put together the bones of the Consortium, coaxed money from dozens of lesser billionaires, and used leverage in the U.S. Senate to make NASA sell off their useless surplus—since, as everyone knew, NASA wasn't going to Mars, anyway. For such a man, setting the orbital health resorts' centrifugal gravity exactly at 0.38 g, plus advertising them with vids of Julia and Viktor bounding in joyous, long steps over the Martian plains—well, that was just marketing. It settled the Mars Effect into the collective mind. She almost regretted making those videos. Almost; it had been great fun, especially in their first mad romps without suits inside the first are odomes. "The Mars Sat is the most profitable sector of all Mr. Axelrod's innovations," Praknor recited. "Further tests would strengthen our advertising campaign even more." "So how many rich folks bolshoi retreats has he now in Earth orbit?" Viktor asked mildly. He tried to be blissfully uninformed of matters commercial. "Seven. I am here to increase that number by nailing down the physiological studies, and..." She had caught Viktor's wary look, eyelids lowering. "And to ask if you would be a ... donor." There was a long hush in the small conference room. "Of?" Julia asked into the silence. "Mr. Axelrod ordered a market survey for new Mars products. The number one item, wildly popular in trials, was ... sperm donation." Julia and Viktor blinked together. At last Viktor said, "From? For?" "We've had some offers from the, uh, Founder's Movement." Julia could not suppress her laugh any longer. It came rolling out in her old brassy Aussie style, a roaring bark that rattled the room and only ebbed into a cackle as her air ran out. "That's the lot that want 'genes from the best and brightest,' right?" "Yes." Praknor apparently did not think this was amusing, because, of course, it did involve money. Julia said, "And Viktor's gotten some offers?" Praknor said, "Indeed. Some as high as $50 million." "Does that include cost of shipping?" Praknor did not get it. "Yes. Frozen—" Viktor joined Julia in gasping, thigh-slapping glee. Praknor sat there staring at them until it wound down. "It is a serious offer." Viktor made a solemn face and asked, "How is sample to be got?" "I'm sure you know," Praknor said stiffly. "And you are sent to gather it?" Viktor asked innocently. Praknor's mouth took on a stern curl. "If you're not going to take this seriously..." "Should we?" Julia shot back. "This man—to whom I happen to be married, I might note in passing—has spent over twenty years in a high-radiation environment, in stressful conditions, and is well past reproductive age—" "And is desired by many women. He is intelligent, rugged, brave, famous—" "Ah, is the famous does it." Viktor grinned. Julia kept talking right over them. "—and should not be regarded as a profit margin item on anybody's budget." Silence. Looking into the other woman's face, she sensed how disconnected they were from Earthside's culture. To pay for famous sperm! The very idea curled her lip. Yet Praknor considered it a reasonable business proposition. Praknor finally filled the hush with, "I can see I am not going to get cooperation from you on improving the margin here—which, incidentally, is negative. Quite negative." "We have lost money from beginning," Viktor said. Julia, cooling down, added, "Since we decided to stay on here, and let the nuke take Raoul and Marc back. But Axelrod found a way to keep us resupplied through the lean years. Now he seems to think he has to make a buck." "The stockholders want to see improved profitability," Praknor said evenly. "Why do I sense another agenda here?" Julia spread her hands. Praknor looked at them both without blinking. "Perhaps we need to meet again, tomorrow. Give you time to think these ideas through." "We think fast here," Viktor said. "Let's meet tomorrow, same time, okay?" Praknor said with utterly hollow brightness, tone rising on the last words. "Uh, I suppose so," Julia said dubiously. Another meeting like this was going to be even worse. "I just don't think we agree on which way the outpost has to go." "We are merely capitalizing on the two most famous people on Earth," Praknor said in a friendly tone. "On Mars," Viktor corrected. Julia and Viktor never regretted staying on Mars; the whole sweaty, frenetic hubbub on Earth repelled them even then; now it was unimaginable. She recalled an e-letter from Marc shortly after he'd returned to Earth, sentiments echoed by every other returned Marsnaut. "You rush into big halls," he had written, "and right away there are reporters and legions of devoted waiting, and they want you to talk. You're there to radiate certitude, and they want lots of that. Even though you've become a walking mouth that shakes hands and you don't really have conversations because everybody wants pronouncements. You are the center of attention of every room you enter and it gets old, old, old. 'What's it like out there?' gets asked a thousand different ways, and it doesn't help to answer, 'Read my book," because they already have, and yet want more. They want a meta-you, the complexity of your experiences shrunken down to recycled moments and phrases: explorer, adventurer, authority on everything above the atmosphere. "You start to notice that as your image swells, the actual you gets smaller, lost. It's a queen bee life, with handlers and lawyers and worse. Compliments rain down on you and it's embarrassing. You do 'events' at which nothing happens except you talk. You enter to applause and make the same opening jokes and pretend it is all happening for the very first time, because it is for them. Even adulation stops thrilling you after a while. The threshold rises, and routine superlatives wing by you with no effect. You don't really know whether they're clapping for you or for the meta-you, enshrined in history yet still walking around, looking for the way offstage. "After you run out of talk and the questions run down, too, out come the cameras. Everybody wants a picture taken with you, and your fixed grin doesn't matter. Celebs move with an aura around them, and to step inside that halo for a moment, get it frozen into digital, is a kind of immortality for them, you suppose, from their excited eyes. They come up to you and flatter you beyond all believability. So many want a precious moment with you, some with whispered theories about alien life and others about God, somehow. So your exit is measured out in ten-second bursts of sudden intimacy. Some might even be genuine if you had time to stop and let all the others fall away and just talk to this one real person. "No moment goes unrecorded, even down to the farts getting up onstage and the nose-blowing when you have a cold. The camera lenses follow you into the men's room. You get advice shouted at you on the street, most of it hopelessly vague ('Get more funding for Mars!') or uselessly narrow ('Get behind mission profile redesign at Huntsville'). You're the boy in the bubble and the walls are always transparent." She took the letter out and read it to Viktor every few months. It worked wonders when their morale was low. 4 VENT R JULIA TRIED TO FORGET the whole hour with Praknor, which had seemed like a day, by tending to the rabbits. She fed them, petted them, and tried not to think. In the last two decades they had mined ice, inflated high-tech greenhouses, and grown crops, and were never in danger of lean diets. But sending meat 100 million kilometers was pricey, so early on they asked for rabbits. The vegetarian movement had continued to grow Earthside, so there were demonstrations, some violent, against shipping rabbits or any other living, high-protein source. In reply Viktor made a video showing how much grunt work they did in a day, with his voice-over saying, "Hard labor needs solid food." It worked. Omaha Steaks won the bidding to ship big canisters of beef and the fish Julia preferred to Mars, at their expense. Axelrod actually made a profit on the deal. The rabbits mated avidly, leaping about, giving them both pets and a long-term meat source. Julia saw no contradiction between caring for the animals and later slaughtering them, but then, she was a biologist. Which wasn't a lot different from being a farmer. And while she had longed for a cat as a pet, she knew the price in meat to feed it. Viktor came in and sat beside her while she stroked a big white female named Roberta. "Forget her," he said, rubbing her neck. "Hard to do." "She got nowhere." "Just like the other ideas, yeah," Julia said, grinning with false cheer. This wasn't the first weird marketing attempt. Years back there was the idea the Consortium had flirted with for a while: send small interest groups to Mars. The "high concept" was that members of the newest Earthside social movement, polyamory—multiple loving partners, with few strings attached—were just the sort to colonize. They were "high-novelty-seeking individuals," so they needed alternative sexual hijinks over the long journeys, or so the argument went. And many of them were wealthy, some from Hollywood, and so could buy their own passage. Further evidence of a society with far too much time on its hands, Viktor had remarked. But there was some sanity left Earthside. The media got wind of the Consortium's marketing research and headlined this as the "sex, drugs, and rock 'n' roll in space agenda," and the marketing director got fired. Mercifully. "I been thinking," Viktor said softly, his way of introducing a new idea. He stroked a big male rabbit thoughtfully. Julia realized it was the one they had named Andy. "You want to get away," she guessed. He chuckled. "Wife always knows what husband is thinking, before he does." She twisted her mouth. "Um. Tell Praknor?" "She is busy talking to Earthside. We should not bother her." "I heard there's a big solar storm on the way, too. It might cut off some of the low-frequency bands to Earthside, the data streams." She grinned. "Praknor will be busy with that, too." "So ... let her show up for our meeting, find us gone." Happily she said, "I like that." The Vent R team of eight was ready, details delegated. Viktor quietly mustered them and got a liftoff time, 0600 the next day. Julia and Viktor were nominally in charge, but they had picked a young biologist, Daphne Newmarket, to call the stages of the descent. Daphne was a lab whiz and had done some limited descents in Vents A and C, nearby. She had a ready smile and ample muscles, infectious enthusiasm, blond hair tied back in a ponytail, and at times made Julia feel a thousand years old. They all went about their tasks without a word to the newbies, particularly Praknor, who was busy setting up her own office and grousing about its size. The bigger habitats adjoined the first domes, affording views and much more space than the rambling, added-on hab Viktor and Julia shared. They used the minicams distributed through the outpost to be sure Praknor was preoccupied by staff and learning the endless details of life inside the linked cans and domes. After the first expedition, the Consortium had reached an accord with their losing Chinese-Euro competitors, the Airbus Group. Once the race for prize money idea worked, big-time, it became the model for all further solar system exploration. In the Vent R descent team were a Brazilian, a Chinese, and an Indian veteran biologist and medical tech, Vaquabal. Those countries plus a dozen others had paid into the International Exploration Coalition, though the Consortium and Airbus still played major roles, grandfathered in—after all, they had put up the money and talent when no single nation would. At 0530 they met in the assembly building, a half-cylinder of carbon composite laid flat side down at the edge of the landing field. The three other crew members were old hands, and they made quick work of the systems checks. Their biggest suborbital lifter was ready, maintenance crew certified, and they loaded swiftly. Gear slid into slot-carries, secured by bungee cords and clamps. Julia got a good seat in the observing bubble. Viktor was copilot, running inboard systems monitors the whole flight. He would have liked to fly the bird, but the Consortium had its protocols ... The liftoff was a steady rumble below them that pressed them at 3 g's, the rusty land falling away quickly. Mars had just enough atmosphere to allow some aerodynamic lift in the rocket plane, so they spent five minutes flying due west and then flipped and began the parachuted descent. A rumbling burst at an altitude of three kilometers settled them down without a jar in rumpled terrain. First, suiting up. Unlike the old days, this was now almost a pleasure. Julia's skinsuit was a marvel of elastic threads that slipped on like velvet. She and Viktor checked and rechecked their seals, oxy, temp. The newer staff rolled their eyeballs a bit, and Julia knew they were thinking, Hey, the new systems self-monitor, y'know. And she did know, but decades of triple-checking did not wear off. One of the job specs for astronauts was an obsessive-compulsive profile. No longer, it seemed. Someday, she was sure, one of the bright, techno-savvy types would end up gasping for air in a remote canyon. There would be a panel review and, my, my, a new malf route would be discovered. Second, out into the big rover that rolled forth from their rear cargo bay. There was far more room inside, thick radiation shielding by water in the walls, and eight big tractor wheels. She could close her eyes and imagine she was in a limousine. Viktor insisted on driving, as usual. Finally, out. Immediately Julia breathed easier. Here was raw Mars. Smooth basaltic flow below them, nonfriable, visible in the belly cam. They crossed low sandy basins ringed by ruddy hills, scribbling tracks across the belly of an ocean now 100 million years dry. The vent mouth was a few klicks away. Viktor wanted to pick up the local geomonitors he had sent over by rocket months before. He yanked each of the silvery lances out of the ground, using the rover robo arm. The crew read them and downloaded their data into a diagnostic program. After the fifth geomonitor, Viktor turned over driving the rover and studied the analysis screens. Frowning, he said, "These show same pattern we saw in Gusev." Uchida, a sharp-eyed geologist, asked, "The magnetic field strength?" Viktor pointed to colored lines that peaked several times over the last several months. "Local magnetic fields go up, so does vapor pressure in the upper Marsmat chamber—only hours later. Same delay when fields fall." Uchida called up a figure on an inset window. "Here's the cause, I bet. We've got lotsa satellite data on this. Here's a figure from a paper on the anomalies in the south. In the north the solar wind flows smoothly around, as it does on Venus. But the incoming solar wind veers around these field peaks—" "Look like magnetic mountains," Viktor said, running his eyes down the sheets of data, histograms, and plots beneath the cartoon figure, checking, checking. The usual scientific acronyms could not obscure the flow of incoming solar winds—like the big one currently blowing—around pronounced mountainlike peaks in magnetic field. "Question is, what causes them? The geologists say it's magma sheets, cooled off into magnetized rock." Viktor looked at Uchida skeptically. "You are geologist." "Yeah, but the agreement between this data and what we know about the magma from seismology, well..." Uchida shrugged. "IMAGE001 GOES HERE" "Not good," Viktor said. "The trouble is, it varies with time." Uchida produced curves showing the rise and fall of the "magnetic mountains"—not everywhere, but in certain spots around Mars. Long silence. "And here's the local vapor pressure at those places." "Um." Viktor studied the curves. More silence. "Julia, what do you think?" Viktor said. Distracted by the view, she studied the curves. Physics had never been her strong point, and she had no idea why the local magnetic fields should vary. But they did, the red line peaking every few weeks, the blue line of vapor pressure following. "Correlations don't have to mean cause," she said. Uchida asked, "Which means...?" "Maybe there's magma underlying this whole area, moving now and then. When it flows in, the magnetic field rises. It melts deep layers of ice, which percolates up into the mat chambers." Uchida pursed his lips. "But there are waves, too. Magnetic waves." He showed them different curves, these labeled with dates. Long sinusoids pulsed for hours, then faded. They combined at times, shaping into complex waveforms. "Hey, I'm not a geophysicist," Julia said, throwing up her hands. "It doesn't make sense to me, either," Uchida said. "Using the magma model"—he nodded to Julia with, it seemed to her, totally unnecessary diffidence—"these waves would come from fluid movements of the magma in constricted passages." He and Viktor got into an extended technical discussion. Julia turned to the big port view bubble and relaxed, preparing herself for the coming descent, and watched a new vista unfold. Crystalline strata sparkled with diamondlike facets in the hard sunlight. Sullen lava flows were as dull as asphalt in spots, and in others where the dust had worn them, shiny as black glass. And everywhere, reds and pinks in endless profusion, myriad shades depending on composition, time of day, and angle of sunlight. The crater cliffs began as brooding maroon ramparts at dawn, then lightened to crimson at noon and slid into blood red in the afternoon's slanting rays. Ayers Rock cm Mars. I went so far away and found myself still at home. In the red twilights of the long years here she had recalled her girlhood in Australia. Not the rural summers with relatives north of Adelaide, with their droughts, brush fires, and smelly sheep, no. Nor the flies and hard work. Instead, the wide skies and wildlife returned to her in memory. The eucalyptus trees were beautiful and endlessly varied, with names like rose-of-the-West, yellow jacket, jarrah, Red River gum, half mahogany, grey ironbark, and especially the ghost gum, which she soon learned was Eucalyptus papuana, appearing in its silvery grace on postage stamps, calendars, and tea towels. They framed the human world of tea-colored, dammed-up ponds, of hot paddocks of milling sheep, of rusting, corrugated sheds tilted into trapezoids—trees standing as silent sentinels at sunset, glowing like aluminum in the settling quiet. On impulse she had ordered a didgeridoo, the ancient echoing instrument of the Aborigines. It came at her personal expense in their fourth shipment—at nearly a million dollars, but they were rich in what Viktor called pseudomoney, from the book and interview rights; though Axelrod seemed to get most of it. The slender tube was labeled in the manifest a "wood trumpet," but it sounded nothing like that. Some Aboriginals had complained that women were not allowed to play didgeridoos in their culture, that she was showing disrespect, but when worldwide sales of didgeridoos and concert tickets rocketed, they fell silent. She learned the trick of holding air in her bulging cheeks and breathing it out while her lungs drew air in, so that she could maintain a long, hollow tone. The skill was unique; normally people never needed to speak while they breathed. The long, low notes fit into her memory of the great Australian deserts, and when she played, the notes somehow sang also of red Mars. Watching Gusev Crater through the wall screens—which improved in resolution and size with every upgrade, so that these days it was as though they had a bay window in each hab room—and playing the didgeridoo, called forth her sense of bleak oblivion. The spareness of deserts had always made her mind roam freely. She could find fresh perspectives on her field biology that way, and in those years had made her reputation as the central authority on the Marsmat. Labs Earthside worked at her behest, comparing Marsmat DNA to Earthly forms. Somehow in her mind her girlhood and Mars blended. She had come to see biology as the frame of the world in those girlish years— the whole theater, in which vain humans were only actors. Mars confirmed this. On Earth, knowing biology quietly brought order to the ragtag rustling of people, ensured that their lives had continuity with the hushed natural world. Just as it could to Mars. On that article of faith she had built their years here together. Over a rise and there ahead the Vent R opening yawned, faint sulfur stains spreading from its mouth. The sharp ridges framing this canyon could not dispel the sensation of spacious wealth. Satellite observations had first detected vapor here, then found hints of vent chemicals. Sure enough, the lambent light glowed through an early morning fog before them. Iron-dark stains mingled near the vent splashes of yellow and orange. Red slopes nearby rose up and darkened to cobalt, then into indigo. Evidence of other ventings, long ago? A dust devil in the distance wrote a filigree path across the rusty plains. She had always wanted to somehow sense their sandstorm sting and the moist kiss of the dawn fogs. All this time, and she had never felt Mars on her skin. Not quite. Then she recalled the hard days of the second year here, just before the first return launch—which she and Viktor declined. There had been one emergency, when she had been forced to run from their first, collapsing greenhouse—headed for the hab's lock in a stretching minute of panic that she would never forget. Raw Mars, sucking at her lungs, drying her skin— "Looks like an easy one," Viktor called out as they ground to a stop beside the broad mouth of the thermal vent. Splashes of yellow and dingy brown marked the sand near the mouth. He pointed. "Vapor deposition from active periods, too." Uchida was robo-master, and he put them to work unloading. Julia paced around Vent R, letting her senses take in details it was easy to miss. Inside a suit made it harder to get the feel of a new vent, the traceries of vapor deposition, stains, erosions. Nothing could live on the surface, of course, in the stinging oxidants and lethal ultraviolet. But the Marsmat could not contain its moist hoard perfectly. Gusev Crater had thermal vents because the huge ancient impact had cracked the underlying layers, letting magma worm upward. The best place to go deeper into Mars seemed to be at the bottom of Valles Marineris. That great stretched scar cut deep and broad. The barometric pressure there could even allow a briny slush on a summer afternoon, melting long-frozen chemical reserves and maybe letting Marsmat get close to the surface. She was curious about how the mat had used the deadly surface for an energy source without getting stung by the ultraviolet and alkaline dusts. There were whole conferences Earthside on just that basic physiological riddle. To get any work done here, she had to keep an open mind. Mars did not reward fixed preconceptions. She looked up at the hard black sky. Faint filigrees fought up there. Probably ionization curls, she thought, from the solar storm streaming past Mars right now and slamming into the thin atmosphere. Survey done, she went back to grunt labor. Compared with decades before, the rover's cable rig was first-class. It worked from a single heavy-duty winch, with a differential gear transferring power from one cable to the other depending on which sent a command. It was the same idea as the rear axle in a car and saved mass. Four telepresence robots were standing beside the fissure. They had six spindly arms, four stubby legs, and a big central control box, all in sleek polycarbon, and she no longer found them odd. These had done the first study, lowering themselves on cables to check for life. Long experience had shown that letting 'bots do a lot of the roving saved time and accidents. Sometimes Julia wondered if Mars could have been explored at all without plenty of 'bots. Sitting warm and snug in the habs, she and Viktor and rotations of crews from Earth had tried out dozens of candidate vents. In two decades they had found that most fissures, especially toward the poles, were duds. No life within the top kilometers, though in some there were fossils testifying to ancient mats' attempted forays. Natural selection—a polite term for Mars drying out and turning cold—had pruned away these ventures. The planet's axial tilt had wandered, bringing warmer eras to the polar zones, then wandering away again. Life had adapted in some vents, but mostly it had died. Or withdrawn inward. Not this vent, though. Somebody back at Gusev made the 'bots all turn and awkwardly bow as the humans approached. Julia laughed with the others, and, as if right on cue, Praknor came on the comm. No preliminaries. "You deliberately stood me up." "Sorry, it was a scheduling mix-up," Julia said. "I cannot believe—" "Hey, got work to do here. Talk later." Julia cut off the long-range comm frequency and switched to local, 2.3 gigahertz. And felt an impish joy that turned up her lips. When she told Viktor, he smiled, too, with an expression she had come to cherish. Long relationships had their rewards. First, as always, they set up the base camp. The team was quick and precise, hustling in the forward-leaning trot that was the most energy-efficient way to move on Mars. Every expedition now, there was new tech to make jobs easier, like the ball tents. She watched them deploy, nearly without human effort. Under pressure any object wants to shape into a sphere. The ball tents took advantage of this. The ball was made of a flexible, thermally insulating material that could take wear and tear, especially the constant rub of dust. Light wires or ropes anchored the ball to the ground as an air tank inside inflated it, with the people already inside. A small chem cracking plant squatted beside each ball, running steadily to split the atmosphere's CO2 for oxygen. Adding hydrogen from water let the cracker build up stocks of methane gas and oxygen, which could then burn to drive the rover. To get powerful methane fuel demanded only the CO2 plus water from buried ice, which was everywhere. With energy, all the chemistry became easy. The robots had already arranged the electrical power supply, comm and computation center, and other backups, all now standard for a descent. Telepresence had come a long way. Bossed from the Gusev tele-team, robots helped the humans put two tanks apiece on their lines, double-clamping them meters above the personal yokes. She did not like the idea of that much mass ready to fall on her and checked the clamps three times. Even robots make mistakes; maybe especially robots. She got into the yoke, all sized and adjusted for her. Like putting on a jacket now, easy. Her shoulders ached a bit, maybe from her swimming. She had gone back to the pool a few times, whenever she started brooding about Andy Lang. Exercise erased cares. "Is ready?" Viktor called. Everyone answered, "Aye!" and they began. The watch crew back at Gusev sent them a salute, a few bright bars of John Philip Sousa. Backing down the slope, playing out their cables, Julia looked up into a bowl of sharp stars—always there, even at high noon. The 'bots got the oxy tanks past the Y-frame that routed the lines. There was a neat get-around, far easier than the awkward old days. Rappelling, bouncing in the light grav, having fun. Down the first hundred meters in good time, just playing out the monofilament cables in a straight drop. She and Viktor were lowest and went down fast, clicking on their suit lamps as the light from above faded. After weeks of indoor work it actually felt good to be doing something—clean, direct, muscles and mind. A large folded diaphragm lay at the bottom, where the fissure took an abrupt turn sideways. "Pressure seal," Julia said, and Viktor nodded. "Four-leaf design," Viktor observed, playing a strong beam of light over the interleaved folds. "Not see that one for a time." Julia took several pictures. "Pretty thick. Got little grapplers at the edges, see? Sturdy." In the girlhood Australian ecology, water was the rare resource. Underground Mars, its pressure was precious. Life evolved to seal off passages, allowing a buildup of local vapor density. Then it could hoard the water and gases it needed, building up reserves from the slow trickle from below. The mat kept itself secured from the atmosphere with folded sticky layers, preventing moisture loss. The vaults below were thick with vapor, but by ordinary gas dynamics that could not be sustained for long. The valve must cut off the losses to the surface, to manage this eerie environment. A pressure lock. But how did the valve know to close? How to respond to pressures and moisture densities? She was convinced that the glows and vapors somehow carried messages, organizing this whole shadowy realm. Biological organisms always had good sensors for toxics they made, their own wastes. The mat exhaled methane and probably had sensors that opened its valves at the right time—or so said a paper with her name on it, and she was halfway convinced. Still, progress in deciphering the mat's meanings had been painfully slow, these two decades. This mat valve was classic, grown at a narrow turn in the vent. As nearly as Julia and other biologists had been able to determine, these were like Earthly stomates, the plant cells that guard openings in leaves. Plants open or close the holes by pumping fluid into or out of the stomate cells, changing their shape. Still, analogies were tricky, because the mat was not a plant or an animal—both Earthly categories—but rather another form of evolved life entirely. Not just another phylum, but another kingdom altogether. Some thought it should be classed with the Earthly biofilms, but the mat was hugely more advanced. Daphne knelt beside a pool covered with slime, next to the valve. The top was a crusty brown, and it dented when she poked it with a finger. Underneath it was most likely a pool of water. "Standard defense against desiccation," Daphne said. Julia had written a paper on that, but she said nothing as Daphne teased apart the mat and scooped up some of the underlying liquid in a sample vial and tucked it into her pack. Let them work, she thought. Anyway, independent confirmation is always good. Julia's paper had concluded that the pools of liquid in mats supported mobile algal colonies, like Volvox and other pond life on Earth. But maybe this one would prove to be different, a local adaptation. Mars was a big place. Julia swept her handbeam around. The mat hung here like drapes from the rough walls. Viktor was taking high-res pictures. "The upper lip of the mat flows down," Julia pointed out. "It covers this pool, keeps it from drying out. We've seen this at about every site." Daphne scooped out some of the filmy water and put it under her hand microscope. "Wow, mobile algal colonies—like Volvox." She took samples. Julia smiled and walked Daphne through the controls of the pulser. Viktor showed one of the crew how to rig the electrical leads to the dark tan wedges of the diaphragm. The best place was along the thin fans, ribbed like the underside of a mushroom. This was one of the big controversial issues, the subject of many Earthside review panels. Many biologists thought that any tampering with the mat was immoral. Certainly, they said, jolting it with currents could cause major damage. But there was no other way to get into the inner chambers. From the start Viktor and Julia had used what worked. For two years they had held out at Gusev on their own, making several descents and setting the protocols followed in dozens of later descents. Julia had reasoned by analogy with some attractive little white sea urchins, Lytechinus, from which she had extracted eggs and sperm, back in grad school days. Back then she'd used a standard technique, running a small current through the water, stimulating the urchin's topmost pore—which duly released its eggs or sperm. The urchins hadn't seemed to mind, and neither did the mat, decades later. Earthside howls of protest meant nothing to them. "Theory easy when your life not on the line," Viktor had said in a public message at the time. There were demonstrations, people wearing Viktor masks, carrying signs saying Torturer and Martian Criminal, Mat Murderer. When an interviewer asked about these, Viktor just laughed. They both published a New York Times opinion piece, reasoning that there were probably many chambers threading Mars, and the mat was large and robust—or else it could not have survived since the warm, wet era over 3 billion years ago. Certainly current was better than squirting the valve with oxygen, as they had at first, in an emergency. That had caused visible damage, killing some of the mat, turning it dead gray. "Field trumps theory," Viktor had said. Viktor triggered the voltage impulse. A hushed silence, just the wheeze of breathing coming over the comm. Then the leathery folds slowly withdrew, inching back, contracting like muscles. The capacitor was a bulky wedge on Daphne's backpack; she was tall and muscular. She peered intently at her ammeter, careful not to over-stress the thickly interwoven tissues. Viktor changed the pattern of the pulser, looking for the best sequence. The folds showed no particular response, but they did sluggishly open. The diaphragm took several minutes to spread, forced by the current flow. A two-meter passage yawned. Pale vapor poured from the opening. "Nineteen milliamps at 0.35 volts," Daphne called crisply. Then in a different tone she whispered, looking at the slow withdrawal, "Wow..." Julia remembered that this was Daphne's first fresh vent. She had trained on Vent A, the "classic" entry where they discovered the mat system. She was doing a thesis on the mat's reaction to repeated violations of its integrity by humans—oxygen exposure from leaks and exhalations from their early suits. Though Daphne had been here a year, Julia did not know how the woman felt about the whole idea. After all, they were rupturing the mat's system. Some biologists argued for a go-slow strategy, checking to see when a vent opened of its own accord and venturing in only then. They had tried that for a year and got in a grand total of two descents. On the second one they'd had to electrically trigger the diaphragm to get back out. Julia and Viktor had argued the issue in endless interviews and position memos. In their view it basically came down to whether they did any research or not, whether humanity ever learned more about the mat. The United Nations had even gotten into the matter, solemnly instructing the Consortium to stop all mat activities. That got them headlines, but they had no way to enforce their words. Axelrod retaliated by declaring that either the U.N. back off or he would lay claim to Mars. He left ambiguous whether he meant the whole planet or just part. This Mexican standoff never got resolved. After a while the Consortium gave the nod to resume descents. The incident stimulated the founding of the International Space Agency, though the contributing nations carefully kept control away from the U.N., of course. Only years later did the world discover that Julia and Viktor had conducted a dozen descents without telling anybody. When they published their results, there was a predictable furor, but that died away, too. Most biologists had decided that staying in perpetual high dudgeon over matters several hundred million kilometers away was pointless. "Honor of first entry goes to..." Viktor played out the suspense for a moment, before bowing. "To Daphne." She was thrilled. The diaphragm was well clear of her body when she dropped down on her cable. She followed her endless drills and immediately mounted a belaying assembly on the wall below. "It goes vertical again," she called. "Come on through. I'm on a bare ledge, easy standing, no mat underfoot." The entire crew followed her and fitted their cables through the assembly so they would have a new, common descent point. All these procedures had been worked out by mountaineering experts Earthside and many trials Marside. They kept mechanical damage to the mat at a minimum. Already, overhead, the diaphragm started easing back together, trying to get a seal around their cables. It wouldn't work, because the cables still needed to have free play. Still, it was reassuring to see the mat here trying the same solutions that Julia had seen elsewhere. It wasn't injured, or else it couldn't respond so quickly. Plus, it was further evidence that the mat system exchanged information globally, or else had evolved this defense mechanism so long ago—against what?—that it was instinctive. Despite decades of wondering which explanation was right, she did not know. Julia paused for a moment. Mars was tiring. Whether this came from the unrelenting cold or the odd, pounding sunlight (even after the UV was screened out by faceplates), or the simple fact that human reflexes were not geared for 0.38 g, or some more subtle facet, nobody knew. But today she was feeling it. She and Viktor were nearly twenty years older than the rest of the team, and she wished for a moment that the Mars Effect would kick in right now. Down into inky depths. They passed by lush mat. Gray sheets, angular spires, corkscrew formations of pale white. These stuck out into the upwelling gases and captured the richness. Some phosphoresced in pale blue and ivory. Other brown growths had earlike fans to catch moisture, a common feature. One spindly, fleshy growth looked like the fingers of a drowned corpse, drifting lazily in the currents ... She got it all on vid. The Mars-studies industry Earthside had classified all these types, coining terms like "extensors," "fungoidal extrusions," "asymmetriads," "symmetriads," and, inevitably, "mimoids" for the times when the mat copied something human. Usually the mat made a rough humanoid shape, as had happened in the second Vent A descent, in the first expedition. But now and then they were greeted with blocky copies of instruments, backpacks, tools. Somehow the mat could sense these, leading to a whole school of thought among biologists that the mat had optical sensors. So far they hadn't found any. That might be because, despite Viktor's Mat Murderer image, he and Julia had not taken many samples. They respected the mat. Several scientists had died while studying it in the first expedition. "Notice how large and complex the structures are," she called to the crew. "Daphne, that's a purple spore-thrower at your left." "Check. Big, multiple pods. Wow." This was half exploration, half a training exercise. Daphne was bright and quick, and Julia wanted to cultivate her as a long-term member of Gusev. She always needed more biologists than she had, especially for descents. Giving a guided tour of a place she'd never been before felt a bit awkward, but she had been on dozens of descents, and training was essential. Most of the crew would return to Earth within a year or so, before the trial of returning to full g became too much. They had to learn and work before then. She could tell by their expressions that they were still in openmouthed awe, even though the others had several descents between them. Was she getting jaded? No, she reassured herself, just accomplished. An air of certainty calmed the others. The harness and yoke under her arms was new and wonderfully flexible, giving her freedom. They worked their way around a protrusion. Daphne led the way—slow, steady, letting their eyes pick out telling details. The brown and gray mat was getting thicker on the slick, moist walls. The rest of the team followed, leading a new batch of climbing 'bots they'd use for recon later. Julia was happy to leave that to others; her whole interest here was to sense a certain something she could never define. Call it presence— the looming feel of the mat, the sensation of being inside its workings. Julia supported her weight easily with one hand on the cable grabber, while she guided down the rock wall with the other. She concentrated. Every moment here will get rehashed a millionfold by every biologist on Earth ... and the ones on Mars, too. "Everybody ready for beams off?" Daphne called. She waited the full minute called for in the protocol. Then: "Switch off!" All around them a pale ivory radiance seeped through the dark. Tapestries of dim gray luminosity. Julia knew the enzyme, something like Earth's luciferase, an energy-requiring reaction she had done in a test tube during molecular bio lab, a few thousand years ago. She recalled as a girl watching in awe "glowworms"—really fly larvae—hanging in long strands in New Zealand caves, luring insect prey. The mat grew ever larger and thicker on the rock walls as they went lower. Mat species covered most of the tube walls now, gray and brown and black, with occasional bursts of orange and blue. They stacked thickly on every available out-jut, then worked up the verticals. Just ahead, thin sheets of mat hung like drapes. Wisps of mist stirred when they passed by. Unlike scuba gear, their suits did not vent exhaled gases, so they could not poison this colony of oxygen-haters. In the first explorations she and the others had done just that. They reached a branching point and elected to go horizontally into the widest opening. Their beams cast moving shadows, deepening the sense of mystery. Within minutes they found orange spires, moist and slick. Beyond that were corkscrew formations of pale white that stuck out into the upwelling gases and captured the richness. More pale, thin membranes, flapping like slow-motion flags. The bigger ones were hinged to spread before the billowing vapor gale. Traceries of vapor showed the flow, probably still driven by their opening the diaphragm. A few steps more and they were in a murky vault that stretched beyond view. As Daphne's lamp swept around, vapors reflected back its glare. Perhaps fifty meters above, mat sheets hung from the ceiling of a vast cavern. Under their beams this grotto came alive with shimmering luminescence: burnt oranges, dapplings of vermilion, splashes of turquoise. A long silence. "H-how big is this?" Daphne whispered. Viktor said, "Can't see the walls." Julia looked down, careful of her footing. "Or the floor, through this vapor." "Beams off in one minute," Daphne called. All around, a complex seethe of radiance. Julia knew that on Earth, mats of bacteria luminesced when they got thick enough. Quorum sensing, a technical term. A way for the bacteria to take roll. A lot of Earthside biologists thought that explained this phenomenon. But they had never stood in shadowy vaults like this—the thirteenth such large cavern found in over twenty years of exploration. To see the rich, textured ripples of luminosity that slowly worked across the ceiling and down the walls was to stand in the presence of mystery. Another silence. Julia and Viktor knew this moment well, had experienced it in the company of many other crews who came and went through the decades. Again Julia felt the churn of somber, slow luminosities stretching into the foggy darkness beyond their lamps' ability to penetrate. There was a sense of silent vitality in the ponderous ferment of vapor and light, a language beyond knowing. As a field biologist she had learned to trust her feel for a place, and this hollow of light far beneath a dry world had an essence she had for decades tried to grasp, not with human ideas, but by opening herself to the experience. They snapped out of it. She let the others work, keeping to the side. Sample taking, vids to shoot, measurements of distance and density and pressure; the usual. There was an advantage to standing apart and watching the humans grub about at the bottom of the vast grotto, their lights spiking here and there like fingers probing. At least they didn't talk much. A movement in the ceiling caught her eye. Pale tan strands came lacing through the mat, stretching like tendons. They made a mass that tilted and worked. Tubular stalks slid, fibers forked into layers, shaping, shaping. An outline seemed to bud up, shimmering and moist. Julia's heart thumped. Again. A palpable sense of struggle, of concentration into this one focus... The others saw it. They froze. "My ... God," Daphne whispered. "I've read your accounts, seen the pictures, but..." Julia had not seen the mat do this for several years. On the second descent of their first expedition the mat had made the same human outline, after two people had died of oxygen loss while exploring Vent A. She knew what to expect but found she was holding her breath. And here came that old prickly feeling again, washing over her skin. Two rough protrusions sprouted at the top. At its base two more protrusions, slabs of dark mass extruding with aching effort into thicker tubes. At least three meters long, in all. And from the upper sides, above the two thickening tubes that now jutted from each side, a third blob, crusted as thick as tree bark, pulling itself out. Viktor said it. "Human shape." No mistake. The mat was responding, as it had before, to their entry. No one had died on a descent since that first strange incident, so the intent could not be malicious. Daphne said softly, "It's so big...?" To Julia her voice sounded dry. "It's the mat's impression of us." "How can it see us?" a crewman asked. "It must sense enough to work out our outlines." "Eyes?" he asked. "The glowing is common," Julia said. "From surface webbed tissues, fed chemically by the substrate." She was sure they knew this from the scientific literature, but it was something else to actually see it, deep in a gloomy cavern. They could be asking questions for the same reasons people talk in haunted houses. "Apparently it communicates through its chambers with light. How far, we don't know." There was more talk, but she just looked at the slow-moving mass. Parts of the mat looked somewhat like giant tube worms, such as those found deep in undersea vents on Earth. But there the analogy ended. The old questions rose in her, still unanswered. Sentience? Of some kind. Enough to control its environment. But sentience implied some kind of selection pressure. She and Viktor had proposed that rationing the meager water resources could drive selection, and predictably, dozens of papers had criticized that. But did it have intelligence? Whole symposia had been devoted to just that issue. Julia had stopped accepting invitations to deliver interplanetary keynote addresses to those. Viktor said, "We are thousand kilometers from other vents. Yet it knows to do this." Daphne said, "And right away." Julia aimed her own microcam at the shape and carefully swept the area to take it all in. Was the mat glow stronger around the form? "This looks about the same as the other manifestations. It'll probably stay here until we leave, as before." "The entire planet is connected?" Daphne asked. "How?" "With these glows?" Viktor answered, not moving, just watching the shape. "Or chemical signals? Or—notice those seams of iron in the walls? Conducts electricity pretty well." One of the crewmen asked, "Was this what it was like when it... killed those two?" Viktor said, "Was, yes. We never knew what happened, and has not happened again. Maybe was holding them, feeling all over them. Had covered some of their suits. Maybe to find out what they were. Anybody's guess." Julia said, "Enough. Time to get back to sampling." Then she sent a private comm to Viktor. "What was that about the iron?" He came closer, so she could see his grin. "You told me way back, in your minilectures, 'member? First sign of life in fossil record was iron oxides, locking up the oxy that the first life breathed out." "So those layers—" She waved a gloved hand at the bloodred seams that ringed the cavern, and which the mat species conspicuously did not cover. "You think they're evidence of the early origin of life here?" "A side issue. I think like engineer. Occurs to me, how to send information from Vent A to here? Chemicals, hard to send so far. Glow—like relay stations through thousand kilometers of caves? Hard. No. But wait—" Viktor's eyebrows lifted. "Layers of iron conduct electricity. Send signals through them, you have global network built into planet." She blinked. "You never mentioned this before." "Never thought of it before—until just now." "Um. If the geologists work on it—" "No need geologists. Already have the magnetic data, right? I showed you. Something funny about this vent, right in middle—yes, look." She followed his pointing finger. The Marsmat definitely clumped close to the seams, without covering them. And the mat was thicker here than she had seen in any vent so far. "How's this explain your data? Big, long-pulse electromagnetic waves?" Viktor shrugged—visibly, despite the suit. "Not sure. When don't know, do experiment." "Huh? What?" "We pulsed the pressure flaps, to open. Use same capacitor on those iron layers"—he gestured enthusiastically—"see what happens." "Uh, now?" Descents were elaborately planned nowadays, and this had not been discussed. "We have oxy. Others, crew, are doing routine work. Let's." She eyed him skeptically. She loved this guy, but he was sometimes crazed. He gave her the big, broad grin, and she laughed. Maybe he was just being male; testosterone seemed to drive guys onward. They got it rigged surprisingly quickly. Viktor was never happier than when he was tinkering, trying something new. Come to think of it, so was she. They attached long black shielded leads to two nearby strata, only a few meters away. Viktor drilled short holes into the stone and sank stub contacts into them. She suspected he had thought of this experiment before, else why bring just the right gear? But let it go. The red bands were of some basaltic iron-oxide-rich layers, probably over 3 billion years old—or so said one of the team, the geo guy. Following protocol, Julia alerted Gusev about what they were trying. Gusev objected right away and pointed out that none of this had even been discussed in preplanning meetings. She told them they were going to do it, anyway. The Gusev operations officer—the OO, whose always-seeing-trouble motto was "oh-oh"—started sputtering. Viktor called out on their comm line that ran up the monofilament to the winch. Reception was good, another vast improvement over the relay system in the first expedition. He went through Expedition Control and alerted the satellite superintendent to focus their orbiting arrays on the vent area. Those had originally picked up the odd low-frequency emissions during a routine orbital scan of the whole planet. Again objections. "Now Gusev acts like Earthside," Viktor said, grimacing. Julia nodded, having fun. "Everything in triplicate." More like playing hooky from school than research, yes. Viktor told them to just do it. Then he turned the capacitor system voltage to the max. Daphne asked why. "Big losses in strata, resistive load, have to overcome. Prob'ly won't work. Get nothing. Still—" and he closed the switch. No drama. Some sparking for a second at the lower connection, then nothing but the hum of the electromotor discharge. Viktor kept it on for ten seconds, off for five, on for ten, then started a more complex pattern. "What's the point of this pulse pattern?" Julia asked. "Just trying things." "You really hadn't thought of this before, had you?" He grinned, lines crinkling deeply around his eyes. "You always say I'm tinkerer. So I do." He kept this up for minutes, watching the pulser readouts intently, and they got a heads-up call from the OO. Julia was off checking on the team, and when she came back over to his "experiment," Viktor said, "Orbital low-frequency antenna is picking up emission. From here." Julia felt a thrill, plus confusion. "Why? What's going on?" "Stimulate a system maybe." Julia frowned. "Some sort of—what?" A team member said over comm, "How about some kind of induced resonance?" Julia had no idea what that meant. Viktor said carefully, "More likely, somebody answering." It took a moment for her to get her head around the idea. Viktor started switching the settings on the pulser. "I'll run a sequence, move around the parameter space," he muttered to her. She could not keep up with his moving hands, the readings for volts and amps. "System has high inductance." "Which means?" "Responds slowly. So I go to longer pulses, see what high voltage gets us." He held the pulser to thirty-second sine waves. Minutes passed. The OO called through: higher emissions from the satellite antenna, also now in thirty-second waves. "Is echoing," Viktor said triumphantly. "What's echoing?" Julia asked. "Do you think the mat has some capacity to—" Crackling came from the stub contacts. Julia looked toward them and saw some vapor steaming out from the rock. "What?" Viktor quickly turned down both volts and amps. "Funny. We are not putting much power through—" The crackling got louder. Sparks at the contacts. "Breakdown voltage?" Viktor asked, staring at the vapor now boiling from the contacts. "Our pulser, we're not near that level. Must be coming in." Julia heard a humming from the capacitor. Green sparks jumped out from the iron seam. "What's—" Then it exploded. 5 THE STROMATOLITE EMPIRE Bringing Viktor up had taken forever, like hours ticking in the back of her mind. Julia had lost it once, shouting at them, pulling at his harness to get it right, trying to be everywhere at once. Literally— she ran up beside him on the monofilament, holding on to the yoke and hanging beside him to see that the pressure seals on his wounds did not come off or start to leak. Early on, she had popped one of her emergency pills, called blue devils by the crew. Hers were custom-designed and kicked in within a minute. She ordered the rest of the team to follow suit and was surprised to find that they already had. Way ahead of me... It was hard treating injuries inside a suit. The only thing to do was to apply pressure wraps around it and seal off the fluid seepage through the woven skinsuit. Still, blood oozed through. Somehow. She spent the whole ascent tending to him, getting them around rocky obstructions, calling to Gusev for help when his shoulder wound opened and started spattering blood onto her visor. It sprayed from the pressure differential, not because he was suddenly blowing an artery. She learned that only minutes later, of course—no help when the blood spattered on her visor and helmet and she could not see much, then smeared it trying to clear her field of view ... and she panicked. Flat out panicked, no apologies, just plain losing it in the middle of a dark vertical cavern with only her to look after him. He was unconscious, thank God, and could not hear her frantic panting, her spitting-mad swearing. She had clicked off her comm, anyway, out of pure carelessness, a clumsy amateur error. Only her training saved her, and maybe him. She moved quickly. Halfway up, leveraging him around a tricky turn, she realized that she was calm again. And though she was fretting below the surface, on top she was alert, quick, crisp. The blue devil at work. But even it couldn't stop her from worrying. The trouble with doing in-suit medical was you couldn't see more than the patient's face, or the wound, couldn't do any diagnostics much beyond blood pressure and pulse rate—which were visible on the suit backpack readout. Plus you were fighting the damned vacuum all the way. Slapping biomed patches on, and then self-sealants, was just about all anyone could do. As they came over the lip of the vent, residual moisture on their suits froze to rime and fell as a dusting of snow. The flakes fumed away within seconds, but Julia lost her hold on Viktor and he spun out over the mouth and groaned. She cursed herself and let the others secure him. She felt exhausted, heart hammering. They got Viktor into the rover at last. They split up into the four who would remain to finish the descent research and the four who would fly Viktor back. Vaquabal knew plenty more medical than Julia, so he did most of the work on Viktor, right after liftoff. Three wounds, all bloody, seeping. Blood pressure low, unconscious, heart rate rapid, and Viktor's eyes jerked alarmingly behind his eyelids. Vaquabal moved with assurance. Julia handed him things from med-stores and did not have nearly enough to do, so she fidgeted and checked the med display screens, most of them unintelligible. Just before they landed, Vaquabal said, "He's stable. I will do the surgery." "It's necessary?" "We must dig out bits of shredded suit and capacitor." "How far in?" "Not far, I think." Suddenly he beamed. "He is in no real danger now, you know." She made herself take a long breath. "No, I didn't." Despite Vaquabal, the operation took a long time, and, worse, he would not allow her in the surgery. There were qualified nurses, after all, he argued. And she was tired and needed to lie down. All this was doubtless true, but none of such advice could she seem to make use of. Instead, she paced and her mind spun and she could not even make any conversation longer than a few sentences. Earthside sent probing questions. Julia had gotten used to having minor incidents blown up into media fodder, but this was real and she wasn't having any, thank you. The time delay was tens of minutes in this part of the orbital cycle, a season when Julia and Viktor avoided talking with Earth at all. One never quite got over the need to get some response back. And the solar storm was blowing gouts of plasma, flooding some of their links with static. The sun was going through rough weather, spewing out big, noisy torrents. Julia sent terse messages to Viktor's relatives, none of them close any longer, and hers as well. Then Axelrod got on the big screen. "What was he doing?" Axelrod asked after the usual extending of concern. "Sending pulsed electrical currents into an iron seam," she began, and tried to explain, but she was not in the mood. So she signed off. As if waiting for a cue, Praknor appeared. The woman seemed to have a talent for showing up as something of far greater importance was about to happen—the expedition planning, the descent itself, and now this. Julia kept her face frozen while Praknor voiced the same sentiments as Axelrod, and then said, "Assuming Viktor recovers—" "Assuming?" A two-second pause, then: "Of course, he's going to be fine, but I meant—" "What?" "—that it underscores the concerns we all have Earthside—" "You're on Mars." "—that you've been risking yourselves here for decades, for an entire generation, in fact—" "We live here." "—of course, and this just underlines the extent of the unknowns, so many unknowns, and—" "Unknowns are why we're here." "—that you both are so famous now, that any possible injury to you gets big news coverage, doubts about the entire program, causes Consortium stock to plunge—" Julia snorted sardonically. "—and such oscillations in profitability are just not in tune with a structurally modern multiworld corporation—" "The only one, actually." "—that you both, when you've really had time to consider the issue in full, should consider giving up this risky life and—" Julia gave her a long moment, but nothing more came out. "And?" "Mr. Axelrod really needs you on the moon." "Why?" "Because it's a lot safer. And there are a lot of doubts about the whole Lunar Enterprises profile. Having big names in charge—" "We're not CEOs. We're explorers." "—will shore up public confidence in that entire arm of the business." Julia let a few seconds trickle away. People respond differently under pressure, and—"You just gave away your whole agenda, right?" Praknor looked suddenly stunned. "Yes. You needed to know. And in a high-stress time like this, you deserve to have all the cards on the table." Julia let herself down easily into a chair. "This is some kind of new management technique, right?" Praknor betrayed a morsel of uncertainty, her lips working. "There's a big nuke on its way. Axelrod wants you on it on the return trip." "What?" "You wanted to know. The spacecraft just barely made the orbital window to get here." "And we don't know?" "It's corporate confidential." "But not an utter state secret, because you—" "Mr. Axelrod instructed me to broach—" "Julia?" Vaquabal was at her elbow. Julia spun toward him, shoving Praknor away. "How—" "He is fine. Awake now." Julia turned back to Praknor, eyes flashing, breath fuming. "We're going to goddamn well live forever, y'know." Viktor didn't want to dwell on the accident. "Just another data point," he said. "Goal is to look for pattern." "Um," she said. He already had a laptop and was fooling around with the magnetic data. She said nothing about Praknor, just sat and let him play. He had lost a fair quantity of blood and taken penetrating wounds at hip, right shoulder, and left side. The suit had absorbed a lot of the blast, and its tight-woven threads stopped the wound from rupturing out into the low pressure. He sat up in the crisp white sheets and shrugged off questions about how he was feeling. The point, he gruffly let her know, was not to feel, but to think. Julia knew this mood was the best signal he could give her about how he felt. She said softly, "I'll talk to the mission analysis people—" "You, we, never believe them," he said. "They have data, but we were there. Big difference." "Something went wrong with the capacitor, they're saying." Viktor managed a dry chuckle, hands crinkling the sheets. "Voltage surge came from iron layer." "Um. Why?" "You notice how mat looked?" She closed her eyes, her method of recalling a scene in the field, learned from long experience. "It... fluoresced." "Da. What else?" "Green sparks." "Da. I check, use physics tables, is right color for simple voltage breakdown in water vapor and carbon dioxide, at low pressure." She patted his hand. "You always do the numbers first." "Keeps you honest. So, at the pressure we measure, what voltage breaks down that gas?" "Um, lots." "Quantitative, is 640 volts per meter." "I'm supposed to be, what? Impressed?" "I was sending couple volts into seam." "No chance the capacitor just failed?" He shook his head sadly at her ignorance. "Discharge came from seam, not capacitor." "So what went wrong?" "Nothing. Somebody got, maybe, enthusiastic. Somebody trying to get through." "To..." "To answer, da." The whole Praknor behavior pattern was another matter. Julia could see that the woman had already rubbed a lot of the outpost staff the wrong way. She had already spent a half year in narrow quarters on the way to Mars, and plainly the stresses—despite plenty of Earthside training—had compressed an already overcontrolled personality into strata of anxieties. Confinement had a way of telescoping relationships and tensions. On Mars, if the staff had had to stay inside for most of the time, it would have become a barking asylum. That was why Earthside carefully studied possible crew members; but the stress of passage to Mars was even worse, and far less easy to project from Earthside simulations. The whirling stellar void visible on interior screens, the looming prospect of aerobraking—knowing that two had failed in the last twenty years, killing the crews—these unsettled the mind. So why had Earthside sent this new-style manager type, whose specialty seemed to be intimidation? Somebody didn't understand that explorers were not corporate types, so they had risked random personal chemistry—nitro, meet glycerin, you're going to have a blast. She had a sudden hunch. Praknor had been sent as a special emissary. Axelrod had probably smoothed the way for her, and now Gusev Outpost was paying the price in crew friction. Another piece of data: Julia checked with Outpost Control, and, indeed, they were pumping extra-big volumes of water up from the ice sheets below Gusev, filling the plastic-lined subsurface reservoirs they had labored for years to install. Mars ran on energy from nuclear thermal units and plenty of water. With those they could do all the chemistry they wanted. It also meant easy refueling for a fast-turnaround nuke. The incoming nuke was "corporate confidential," which meant that Axelrod had yet another trick up his sleeve. There were a few more days before it landed, ten klicks away, at the pumping station. So Julia avoided Praknor and worked away in the lab. It could be her last chance to do biology that mattered. The Stromatolite Empire. Dreaming, she was standing on mud flats at low tide. Volcanic cones towered over a haze of gray ash, the landscape lit by spurts of hot lava. Streams of lava hissed into a shallow dark sea. Waves whipped by high winds pounded basalt cliffs. Hummocks of basalt stood on the shoreline, glistening when the fitful sun struck them with highlights of crystals. Gray-green life had begun on these mounds, clinging, fighting for nutrients in a violent land. Clouds parted for a moment, and she looked up, expecting to see the moon's pale face. Instead, a blue-green sparkle danced in the turbulent air. A swollen crescent moon leered at the yellow horizon. Earth. And maybe Mars, even earlier. The Stromatolite Empire. She studied the research summary squirted up from Earth at her request. She had not thought of looking at the data on stromatolites in this way before, but as soon as she did, plenty of researchers were willing to help, so this arrived within hours. Life on Earth had taken off after an excruciatingly slow start. Though simple cells began within about 400 million years after the planet had cooled off enough to allow it, they took 2.3 billion years to get around to making complex ones—eukaryotes—with machinery in a nucleus. Another 400 million years plodded by before simple seaweeds arrived. Stacking cells together to make more complicated plants was apparently a tough invention, taking 600 million years more. Only when all this was in place, barely 600 million years ago, did the Cambrian explosion of species occur, and complexity took off on its exponential rise. But by the time all this runaway action started, the plants had flooded Earth's atmosphere with oxygen, making things tough on the anaerobes. So they had mostly retreated underground, where they still thrived down to depths of several kilometers. Having a blanket of poisonous oxygen over the surface had probably inhibited them. So she thought of looking back, at the microbial communities which had survived through almost all the Earth's history—stromatolites. As an undergraduate in Adelaide she took a trip to see what they looked like and was astonished that they seemed to be just like rocks. Irregular, encrusted columns of rock. For decades now she had seen just such bulging columns of microbial life, deep in the Martian caverns. Forms on both planets used DNA to pass on their genomes, but there were myriad differences. Earthside biologists were still fighting over the implications of this, most of the discussion going right by her at high velocity. She was an author on dozens of papers, arguing both sides of the issue, with titles like "Identity and Evolution of Martian Vent Endosymbiotic Methanogens." (After the first few, Viktor did not want his name on such tongue-twisting papers and did not even read them anymore.) Either Mars had sent life's early kernels to Earth, in shards blasted out by incoming meteorites, or the other way around. She didn't care all that much which way the argument would turn out. It was all wonderful. Geologists gauged the growth of modern Earth stromatolites by seeing how much they had covered over old soft drink bottles from the 1920s—about a millimeter a year. The microbial mats were slow, careful, with the gingerly care of the vastly elderly. And when poisonous oxygen appeared, they had lapsed. Their species numbers fell, but unlike the vast run of all life, they did not die out. Along a few shores and lake beds, the mats still waited patiently, much reduced, in their warm salty ponds, waiting to again dominate the oceans... "IMAGE002 GOES HERE" She remembered her dream. Stromatolites on Mars? As the thin atmosphere chilled and drained away to space, the microbial colonies had to retreat. Into the soil. But without the competition of the oxy invaders from above, they had not suffered the losses their Earthly brethren had to endure. They could spread in the larger caverns and rock pores the light gravity Mars allowed, find new ways to develop, make a network that now wrapped in labyrinthian caverns through the planet. Perhaps they were not now separate species, but something that Earth had never seen: an integrated organism, based on cooperation, the Martian Way. Viktor hobbled into the conference room, leaning on Julia, scorning the crutch she offered. The physicist Brad McMullen was waiting for them, the display screens around the room alive with colors. Uchida was working at a keyboard. "We're getting plenty of those signals from the Vent R area, sir," Brad said. Viktor let go of Julia and spun on his foot, letting the low grav bring him around and into the waiting chair. "No 'sir.' Just 'Viktor.'" "Uh, well, here—" The activity map told its own story: low-frequency signals, magnetic pulses really, of large amplitude. The orbital antennas had picked up far more activity after the capacitor accident. It spread over a broad spectral band and was tapering away only gradually. "Could not be from this solar storm that's blowing by us?" Viktor asked. Brad shook his head. "We're getting surges from that, sure. The storm plasma emits higher harmonics, which can screw up our readings on the ground—but we can filter that out." An orbiter had even caught a burst of light from the original vent, Vent A, at the time of the electrical surge at Vent R. Viktor beamed. "See?" he said to Julia. "The somebody who answered is trying to find us." Julia eyed the display suspiciously. "What's the team at Vent R report?" Brad said, "Plenty of light coming from the mat. They've wormed their way into some pretty big caverns—one bigger than a basketball stadium, Daphne said—and they can see all the way across the thing, just from the mat glow." "Damn," Julia said. "I should be there." "They send pictures?" Viktor asked, and she knew it was to distract her. Brad nodded and popped some up on the screens. Julia gasped at the brilliant ivory glow, the steepled vastness above, long streamers of mat growth hanging in billowing orange banners, hollows and shadows and flickering luminosities, like a thousand candles lighting a stony cathedral. "Something wants to talk," Viktor said with a slow smile. "To do the talk magnetic." Praknor skipped the introductory smile this time. "I've been instructed to curtail your exterior expeditions." Julia had warned Viktor, but still his nostrils flared. "No descents? Preposterous." "The corporate Accident Review Board has reviewed your conduct," Praknor said evenly, looking at Viktor with a remote, steady gaze. "You conducted an unapproved experiment involving high voltages—" "Couple volts, milliamp currents," Viktor said. "—endangering all personnel, and suffering potentially fatal wounds. All without review, or ever a suggestion of prior advisement." "Was field experiment." Viktor leaned forward significantly, clasping his big hands in front of him, eyes narrowing across the table at her. "You have done such?" "I am a cross-science specialist, and I know procedures must be followed in every hazardous environment. So does the Consortium." "Um." Viktor raised his eyebrows. "Very impressive terms, but is not fieldwork." Praknor gave each word weight. "Without. Proper. Procedures." "That is nature of field. New things happen." "I'm afraid the Consortium views this entire incident as a severe wake-up call. You two are our primary assets. The Consortium cannot allow you to risk yourselves." Julia had been holding herself back, but now said as mildly as possible, "Don't you think that's up to us?" Praknor said evenly, "We all have the highest respect for you. Your faces are known globally, your—" "We are just people trying to do a job." Praknor looked stymied, her lower lip turning in, teeth pressing the blood from the whitening red. She blinked, making a decision. "All right, then, here it is. Mr. Axelrod wants you back on the moon." A moment's silence, then: "Why?" Viktor demanded. "Nothing we can do there." "You'll be safe, secure, you can retire." Viktor looked more puzzled than affronted. His brow wrinkled, looking like the grain in a weathered board left outside. "Too young to quit!" Praknor's face softened just a bit, her eyebrows rising. "Frankly this isn't a middle-aged game here. Never was. It's tough." Julia stiffened. "We know that better than anyone." "I'll skip over the early days, when, as I recall, Viktor got hurt in a vent. Julia, just last year you sprained an ankle. Three years ago Viktor broke an arm." "Accidents, is all—" "Happening more and more often to you two—" "—and all better now," Viktor finished. "And what about Mars Effect, eh?" Praknor took a breath, soldiered on. "Still—" "Moon is boring!" Viktor slammed his hand on the table. "Is dead!" Praknor said, "I didn't want to put it this way, but Axelrod said to use trumps, so—I'm just relaying word here. It's a Consortium decision, not revocable. You're going home." "Moon is not home," Viktor said quietly. "You can't go to Earth, the gravity would immobilize you." "Moon is boring! Nothing to do." Julia said mildly, "The big microwave antennas the Consortium's building, the solar cell farms—they're built mostly by robots, right?" Praknor nodded quickly. "You could learn all those new technologies, supervise—" "Plenty robots here already," Viktor said. "Not good at exploring. Maybe putting up Tinkertoy microwave antennas is okay for them. Not us." Praknor tried a quick, unconvincing smile. "How about taking it easy for a while? You could fly in the new pressure dome they're putting up—" "Like Andy?" Julia shot back. Praknor stiffened. "I didn't think you would bring that up, since it was under your directive that he—" "Hey, it was his idea, and he had plenty of experience." Julia was sorry she had said it the instant it was out. Even if it was indeed true. Praknor said slowly, "That's not how the Consortium sees it." When they were alone, Viktor was surprisingly calm. "We start publicity campaign, right now. Go to Earthside media." "I agree," Julia said, though she had a sinking feeling. "Let's go through the Consortium publicity office. We know them." "Even so, they'll block us. Maybe capture the broadcast." "Not if it's an interview." "Um. Maybe best, yes. I'll send inquiry to some friends, start them working on it." "We need a big splash." "I'll play up my injury, maybe say I can't travel." He grimaced. "Is lie." "A media untruth." Julia patted his hand. They tried to get back to work. But Julia could not stop thinking about the fluorescent-lit, acronym-ridden, numbing culture she saw on the vid. Some would slop over onto the moon, certainly. Any civilian with the bucks could buy a week or two there in the "pleasure domes"—though the orbital Mars Sats were the big draw and cheaper. Even the thought of rubbing up against a steady stream of such people made her tired. Mars never had. She wasn't young anymore, for sure, but there were moments when she still felt youthful jolts of inexplicable exhilaration, energy mixed with yearning, a certain simmering sense of invincibility. Maybe it was Mars. Here you needed rugged confidence, or else you'd cower in your hab, afraid of the whole wide world outside. So she and Viktor had developed their own aspirations, steady like a faith that did not need expression, a hope that could sting like chlorine. Without Mars, she knew she would never feel that way again. Daphne found Julia, intersecting her in one of the subsurface corridors. "Hey, got some results," Daphne said brightly. Julia blinked at her. The Vent R descent seemed like an age ago, though it was only a week. "Uh, great." Daphne's "office" was a tiny compartment. They wedged in as Julia reflected on the comparatively vast spaces she and Viktor occupied. "We got a good long way down, over a klick," Daphne said. "Into side channels, too." On the wall a satellite photo appeared, overlaid with blue lines. "Here's the subsurface map. Got most of it with those climbing 'bots we took down." The lines followed a jagged but mostly radial pattern, fanning out from the Vent R mouth. "And now we add the magnetic field data, waves emitted from—" Orange lines appeared. They were broader, mostly patterns of cross-hatching. "They follow the mat," Daphne concluded triumpantly. "Not perfectly, but close enough that it can't be an accident." "Striking." Julia peered at the cross-hatching. "The magnetic waves, the low-frequency emissions Viktor has been working on—this is where they come from?" Daphne was a biologist like Julia, but Mars staff had to be versatile. She said, "I know, I can't see any reason why they should overlap—but they do." Julia smiled. Daphne was a lot like her younger self, plunging ahead. "So the mat uses electromagnetism, too?" Daphne traced with her fingers some of the lines, thinking, not answering right away. "Seems unlikely, doesn't it?" "Evolution is inventive." "There are electric eels that use charge to find and shock prey. But waves..." Daphne shrugged. "What's that saying of yours?" Julia wondered if the staff thought of her and Viktor as pontificator has-beens. Then she realized that, indeed, she did have stereotypical remarks. Like "Correlation may not mean causality?" "Yeah, that. I remember hearing that the disease rate in Europe goes up with temperature. But it's the insects carrying the diseases that respond to temperature, get more active—not the weather making people sick." "So the mat may not respond to magnetic fields directly?" Daphne spread her hands. "Sure, I—" "But then, what blew our capacitor?" Viktor called her, and she found him collapsed on their bed. "You're overdoing it." He ignored her. "Got a squirt from Earthside, mysterious." "Axelrod." Not a question. "Assistant to him. Said the moon antenna system launched a powered sail toward us." Julia sat on the bed and felt his brow. Maybe a little warmer than usual. "This soon? I thought they weren't going to have the power transmission system up and running for years." Viktor thumbed on their wall screen. A deep-space picture, magnified to the limits of resolution. A silvery disk hung in the black. Below it, hanging by struts like a spiderweb, was a small golden package. "To boost this lightweight package to high velocity takes only a few antennas. Axelrod said to send this as test package." Julia had paid little attention to the grandiose Consortium plans. The collision between global climate change and rising energy demands was the biggest international issue Earthside. Storms were wrecking cities, the ocean was lapping at dikes, Kansas was a desert and India had floods. Yet the cheapest path to prosperity was to burn cheap coal and let somebody else worry about the accumulated carbon dioxide in the air. A classic tragedy of the commons—profit was private, waste was communal. And here came the Consortium to the rescue. Viktor's next picture showed the beginnings of the microwave antenna network Axelrod's web of companies was building. Eventually it would trace around the moon's disk, as seen from Earth, because that gave the highest focusing of the incoming microwave beams. Those beams would strike football-field-sized receivers, just chicken wire really. The induced power in those wires would feed directly into Earth's power grid— cheap electricity. The original power would come from the harsh sunlight hammering at the moon's surface. Captured in huge solar panels, fed to the microwave antennas, the energy source would be in its way an environmentalist's dream: the environment affected would be a quarter of a million miles away from Earth. But that was a decade in the future, at least. Robots were making the solar panels on the moon, extracting iron from the lunar regolith with magnets, making wiring from it, building the antennas. Nearly all raw materials they got from the moon itself. Julia hadn't even realized that they had any of the big lunar antennas up and running, but there they were—big wire cups on slender stalks, light in the lunar gravity. They pointed skyward and radiated power to the silvery sail. "Pushed it out of orbit around moon," Viktor said, thumbing through more images of the sail. "Gave it speed. Sent it into long orbit for Mars." Julia arched eyebrows, impressed. "Nice toy demo, but—" "Its job, they say, was to get here before that big nuke." "Huh?" "Nuke had already left when Axelrod decided to send this," Viktor said. "To beat its time in getting here." "Why?" "That is the mystery." Viktor grinned, though she could see he was bone-tired. "Just showing off, I bet." He waved this away. "Squirt from Earthside says not. Axelrod wants me to pick it up when it aerobrakes." "What? Why—wait, you can't do it." "Orders." "You're in no shape—" "They said we should both get it. For our eyes only." He grinned, always happy when intrigues got more complicated. "When's it get here?" "Two days. Sail burns up on entry. Payload chutes down. Trying to set the package—that little golden-wrapped thing, you saw?—down in Gusev." "Three days before the nuke." Julia frowned. "Damned funny." "I like mysterious." 6 LAST TRAIN OUT OF DODGE To KEEP HER MIND off their situation, she puzzled over the Vent R incident. Science beat politics every time. Viktor had pointed out the biggest clue: the correlation between water vapor pressure near the site and the magnetic waves. Except for birds who used the magnetic field to find their way on migrations, Earthly life mostly ignored magnetism. A few bacteria carried minute bits of iron and appeared to orient in a magnetic field, but how it helped them was unclear. She shook her head; would evolution have produced the same answer to the riddle of survival on Mars as on Earth? She sat and thought and watched the Martian landscape as sharp shadows stretched across the afternoon. A thin filament of cloud towered in the distance. Sure enough, it was in the right direction for Vent A. The mat was opening its thick seals again, following a pattern no one had deciphered yet. She added one more data entry to her slate; this was the first venting in several months. And nobody knew why the mat did it, though there were plenty of theories. Vapor pressure... The early discovery of methane in the Martian atmosphere, at ten parts per billion, had suggested that life might be the source—but it was not a clear proof. Scientists could always rummage around and find other interpretations, which in turn suggested further tests, and that was the dance of science itself. Maybe a recent volcanic eruption had vented the methane from the warm interior; that happened often on Earth. Or perhaps, since comets were known to have methane ices, one had blundered into the atmosphere. And a calculation showed that the water vapor in the Martian atmosphere, kindled by ultraviolet, could react with the methane and erase it in a few centuries. So any volcanoes or comets had to be recent events. But in the hundreds of thousands of orbital photos there seemed no clear evidence for recent volcano ventings, or impact craters from comets. So the issue had drifted along without clear, sharp confirmation for any view. Until the Marsmat discoveries. Now they knew that the Marsmat could send signals over great distances, hundreds of kilometers at least, far larger than any single mat. They had seen that in Vent R, when the humanlike image shaped up out of the mat on a first visit. Why communicate over such scales? To sense a coming pulse of hydrogen sulfide vapor from deep below, tell the entire network, and make ready? A clear survival value in that, she supposed. Could organisms evolve such detailed response in this harsh place? Could an Earthly biofilm do it? Maybe biologists had never noticed. On Earth mats like the stromatolites were considered to be early, primitive forms with severe limitations and no future. The biofilms had just been outrun by other forms in the rich, warm, wet oceans. Julia went out to the big greenhouse and gardened to clear her mind. They all went to the greenhouse when they were tired of the endless sunset hues of Mars. Or when they longed to see something alive that wouldn't talk. That first whiff of greenhouse air was a great morale boost. Greenhouses processed air better than any filter, carrying a particular fresh scent unlike Earth, undefinable, more raw. She would miss it. She barely nodded to others working. Privacy was precious, and they'd adopted the Japanese habit of not intruding on one another's space unless by mutual agreement. She skipped the fields of wheat, rice, and potatoes, various beans, lines of broccoli and tomatoes. These looked ordinary, and then she walked under the canopy of carrot stalks so green they changed the Marslight. No one could predict what the combination of low gravity and low sunlight would do; some crops died, others became green gushers. There was something very calming about being surrounded by green leaves and vines, all nodding gently in the endless updraft. To strengthen trees and stalks, they had to run breezes, fake winds. She recalled how, in the early years, she and Viktor had taken advantage of the absence of others, off on rover trips, to make love amid the churning plants—exciting, though chilly. It'd always been a big turn-on for her to look over the shoulder of a lover into the swaying foliage of a tree. Viktor said it showed she was a real primitive. She worked with her hands to free her mind—pruning, harvesting, helping. Even a biologist had to keep reminding herself that life found ways nobody could foresee. Growing up in Australia, she had marveled at lizards in the deserts that absorbed water through channels in their feet, because they were most likely to come across moisture in shallow damp spots. On the other hand, nature made its creatures narrow of purpose. Silently she joined a team that was harvesting corn. It was good, solid work, letting her hands go and have fun while her mind could idle, running on its own. Cut, sort, bag... One winter she had gone out on a Girl Scout trip, and they had stayed overnight in a bush farmhouse with a tin roof. In the night birds thumped heavily onto the roof, because when they looked down from their migrating patterns, it reflected the moon and so looked like an inviting pond. She had rushed outside and found dazed ducks, given them water, and off they had gone—no doubt to make the same mistake again, because nature saw no point in giving them the processing power to learn from experience, much less to tell others of their kind. If there had been many tin roofs, they would never have made the migration, never made new ducks. Nature had not made them too narrow, not this time. Too narrow ... Could evolution have found a way to give the mat some use for the magnetic field waves? It sounded crazy. Julia was thinking so hard about this that the burst of hand-clapping startled her. When she brought in a bushel of picked corn, her coworkers applauded. "Fastest picking I've ever seen," a man said. Julia was startled. She had not even noticed. Sitting in the cafeteria, nursing a cup of coffee, a young woman from the bio section asked, "Mind if I sit down?" The room was crowded. Julia waved her into a chair. Stephanie, she recalled, a biochem type. They had even been on a dozen-author paper together, on how the Marsmat used sulfur for energy. "Nothing much to do," the woman chatted on. "I'm a sexile for the next few hours." "Uh, what?" "Exiled for sex. My roomie has a guy in." "Uh, oh." At first Julia blinked, affronted at this sudden bolt of intimate detail. Then she realized that this was another effect of living in a tight little base, however grand the views were outside. Unavoidably, formal hierarchy dissolved under the rub of informal daily life. See the commander daily slurping coffee and washing dishes, and pretty soon he doesn't look like the leader anymore. Even legends did scut work—or should. The woman started happily chattering, and her talk went in Julia's ear and out the other. Only when the other woman started to notice did she make an attempt to respond. Julia was busy realizing how out of touch with the younger staff she was. Could Praknor be right? Time to hang it up? Praknor tried to put her foot down over their excursion, eyes flashing. "No, it's ridiculous." "Axelrod said we are to recover package," Viktor said. "You can barely walk!" "I'll do the walking," Julia said. "The route is along one of our standard drives, and I can do the driving, too." "It's twenty-three kilometers—" "We leave at dawn, back in plenty of time." Praknor sat very still. "I believe we must define just who is now in charge here." Julia said in a deliberately conversational tone, "Well, I hardly think it's a dichotomous choice. Still, no need getting our knickers in a twist when we can defer to Earthside on this one, eh?" Earthside would be very surprised to be asked; tight control of excursions had faded away years ago. But she was counting on the fact that Praknor was so green she didn't know what the routine was. Viktor picked this up. "And can talk to staff, too." Praknor sputtered, but Viktor's intuition proved right. The staff would support the venerable Marsnauts, not a fresh manager who hardly had her Earthside smell worn off. Julia sent a long message to the Consortium, and Praknor wrote one even longer. Off these went. Experience proved the rule: Earthside dithered for hours. Praknor got distracted with work. Nudge nudge, wink— So they went. It helped that everybody was talking about the new results from the Pluto expedition, and a bit distracted. Nobody asked questions. The ISA discovery of a biosphere there had electrified them all. Julia had no idea what to think about the Pluto reports. The biology seemed impossible. But then, so had the news that the solar system's bow shock was moving inward. She had long before learned to let the outer world go on, without her attention. She put aside everything and focused on the task at hand—always, on risky Mars, a good idea. Going out, Julia noticed how much of the landscape was now rutted and marked by the ever-busy humans. She could see the towers of their water-drilling fields in the distance. Some pingos nearby were thoroughly excavated, both for bio-signatures in the deep ice deposits and for geological data; then the ice was harvested, leaving holes yawning like mouths. Not far from them was the crumpled descent package. This was yet another miracle of design. Hardly the size of a coffee table, the smart, carbon-fiber shell had survived the blistering plunge by flying itself. Stubby wings let it use the infalling energy to bank and lift, gaining the time to locate Gusev. Viktor insisted on parking only meters away, so she had a very short walk. The announced reason for this flight was some vital small parts for a malfed pressure control system, and they were indeed most of the payload mass. But when she lifted the parts out, there was a cylinder at the back. On it in big stenciled letters was FOR JULIA AND VIKTOR ONLY. In Axelrod's hand. She got it back into the rover, and inside was a rolled-up letter. "It's so like Axelrod to send an old-fashioned letter rather than an electronic squirt," she said, opening it. "Hang the expense," Viktor said. "Is also much more secure this way." They read it together. "Now will be much fun to talk to Praknor," Viktor remarked. "I can't believe it," Praknor said. They showed her the letter. Axelrod had even written it by hand; he never trusted the security of digital media and more than once had been proved right. Praknor read it over twice. "The big nuke is for heavy Mars hauling, yes." Viktor began, as usual, by illuminating the tech angle. "Will land with plenty supplies, rovers, support gear. Rut will take off with water in holds." "This is insane," Praknor said quietly. "Maybe, but is orders." Viktor even smiled. "I thought, I was told, I was to prepare you for transfer to the moon. But, but—to send you to Pluto!" "They need help," Julia said. "Nobody there has experience dealing with alien life, communication—" "And you..." Praknor didn't finish her sentence, but Julia knew how it went: You over-the-hill types are going to ride out there in the biggest, best nuke yet built, to help? When young people like me are available? Ah, the arrogance of youth! "We are only part of it," Viktor said crisply. "This nuke has crew, supplies needed on Pluto, just needs us for maybe helping with the communication problem. And Axelrod, he has money in his mind, too." Praknor shook her head. "There's no money to be made at Pluto. That's an ISA expedition." Julia suppressed a smile. The whole nuclear rocket program had emerged from military, commercial, and exploratory arms. The Mars Prize itself had been the first step toward true international cooperation, and it had drawn two entries: Axelrod's Consortium from the USA, flying in big chemical boosters, and the Euro-Chinese end run, using a nuke. After that, it seemed obvious that merging abilities and assets, with economies of scale, could make space a far easier enterprise. Ultimately that cooperation had formed the International Space Agency. Axel-rod's can-do personality had driven much of it. Julia spoke with him nearly every week, still, but her memories of him were over two decades old now and fading. But she was sure that the man would never do anything that did not hold at least the promise of profit. "You forget the ice asteroids," Viktor said. Praknor just looked perplexed, so he went on. "Inner solar system was dried out by early, hot sun—the T Tauri stage, is called. Sun's light pressure blew lots of light elements out, so the gas giants are all beyond the asteroids—and even 'roids are dry. To develop inner solar system, need light elements—water, carbon dioxide, methane. There are whole chunks of that orbiting out beyond Neptune—the Pluto expedition found lots. Tested a few. Axelrod wants to move some in, far in—to here—so Consortium can use." Praknor snorted with derision. "Move asteroids? Wouldn't it take huge energies?" "No, little needed. 'Roids out there move with orbital velocities of maybe one, two kilometers per second. Slow. Take that away, they fall straight in toward sun." "But even a small change, for such a huge mass—" "Use nuke reactor. Melt some of ice, heat, blow it out back, makes rocket. Use the 'roid's own ice to move it. Cheap." Praknor blinked, her mouth pursed, and then she stiffened. "That's what the board thinks?" "Axelrod says so in his letter," Julia added. "Me, I think he wants to get all the help he can for the Pluto expedition. After all, it's getting plenty of media attention—distracting people from what we're doing here." Praknor said slowly, "He wants to get back in the game." Julia could tell by the subtle sag of Praknor's shoulders that she was accepting defeat. "If he can supply water to people in the asteroid belt between Mars and Jupiter, he can capture all the mining industry. There are more metals available in the belt than in the outer crust of the Earth." "But is more," Viktor said, eyes crinkling. "What?" Praknor was guarded, already hammered heavily by this torrent of news. "On Pluto expedition is his daughter. And they are in deep trouble." Before falling asleep, cuddling close, Julia said thoughtfully, "Didn't these last few days seem, well, a bit odd?" "How you mean?" Viktor was sleepy. "First we get Praknor, who made a mess of dealing with us. Got our backs up." "Axelrod is not diplomat." "No, he's an order of magnitude better than mere diplomats. He's a conniver." "How you mean?" Viktor turned off his light and got his skeptical look on his face. She knew that he would listen for maybe a minute, then close his eyes and drift off to sleep. Very efficient. "Praknor pushes us all out of shape by threatening to ship us back to the moon. She believes it, too, and is the most abrasive person I've ever seen sent out here." "Um." He did not open his eyes, but he said slowly, "So we think this is first of new breed." "And she can point at the big nuke, due in soon." "Last train out of Dodge." "Huh?" "I been watching movies. Westerns." "Oh. Then Axelrod slips in this fast sail message, absolutely authentic, in his own hand." "Personal touch." "Good cop, bad cop." Viktor chuckled. "Praknor, very bad cop. Good cop saves us from a routine life on moon. Holds out Pluto, where the action is right now. The nuke is already partway there, see? Energetically Mars is third of the way to Pluto." She ran her hands over his back. "I love it when you talk technical." "I know this." She made a rude noise. "So we're to be part of a grand expedition, helping out his own daughter—and the Consortium can play it as a rescue plus science." "Sells well." "You got it. Great story, featuring our famous, fave heroes from the Mars Race." "Is what Axelrod intended all along. Moon was phony choice." She slapped his ass cheerfully. "And now we're glad to grab the chance! A month ago I'd have resisted leaving Mars at all." "Now we are ready." "Yes, we are." "Axelrod smart guy." Julia nudged him. "Plausible, right?" "Does not matter." "What? Why?" "Because he could just order us to. But this way we're enthusiastic. Much better to have employees who want to do the work, da?" She felt offended. "We're not employees!" "To Consortium we are." He rolled over and put both arms around her. "Let them play their manager games. We have the fun. Is all that matters." PART II THE FAR DARK Immensity is its own justification. —William Rotsler 1 the zand Light—pale, BLUE cold, little more than starshine—crept over the gray ice plains. Dancing blue and green auroral sheets shimmered in the deep blackness above. On the dayside skyline a turbid yellow stain swelled at the hard brim of the world. Then a sudden blinding-bright point threw stretched shadows across the hummocked land. The seventy-seven hours' night was over. Sunlight, waxing yet still wan, laid siege to a rampart of spiky white needles. Temperatures edged up from the night's 96 degrees Absolute that made everything here rock-solid. Even the methane ice hills loomed like rumpled blue steel. But the coming of the sun—now a pinpoint only as bright as a streetlight a block away—changed the landscape. Methane needles caught the sunglow, and their sharp crystalline spearpoints curled, sagged, slumped. Gray vapor rose to meet the tepid dawn. It met even colder, drier air from Darkside that came sliding in on a rushing wind. Methane rain fell in wobbly dollops, spattering on black ice. The zand awoke. It peered out at the slow awakening of a slumbering land. Its body stirred. These bleak days were not remotely like the warm breath of summer, now long lost. Centuries would elapse before Pluto again saw methane ice sublime into its pink haze. The grinning crescent of Charon above loomed large but was still too small to hold its gases. The eons had stripped Charon of its methane, leaving bare, rock-solid water ice. During the richly remembered summer Charon had grown a pearly vapor tail like a comet, while still stolidly performing its gravid waltz with Pluto. Now its vast, pocked plains yawned above as each world rotated with the other, face-to-face. Like dancers forever doomed to the same pace, the ice world's cycle repeated every 6.4 days. Surface relays kindled by the sun sent crisp neural discharges coursing through the zand's body. The spherical shell that had sealed it from the long night split and retraced. Brittle rods clacked, withdrawing inside, finding fresh socketings in an internal skeleton. Pulpy organs sluggishly awoke. In such deep cold, only organic solvents could ooze to a slow, throbbing pulse. The zand turned its ice-glazed lenses directly toward the hard point of radiance. This prickly stimulus was just barely enough. Radiance. Aided by energy hoarded through the bitter night, thick motor rings of muscle along the zand's daytime body began to pulse. The great beast moved. Sluggishly. Just before easing into sleep the night before, the zand had marked an outcrop of foodrock and carefully covered it with snow. Now the ever-thickening rain beat upon the cache. The zand splashed through rivulets to the top of the knoll, fighting the humming wind that blew toward the dawn. As it struggled uphill, the chilly breeze seemed to be always against it. Finally the top. Stiffly the zand extruded its blower and drove the rest of the damp, melting snow off the outcrop. Nothing. Something had harvested this lode in the long night. Darksiders. One had gotten by their fragile lines. Perhaps to do damage elsewhere? Despair swept through it. Darksiders could slip through because the zand were all weak, terribly weak. Then it put all thought aside and rested. Dizziness spun through the long body. Each move sapped its precious stores, and it knew now that it had used too much from its small stock of energy. This was going to be a very near thing. It mustered more chemical energies within itself and went on. Its legs creaked and trembled. Desperately it turned its head to scan the area for food. From this hummock it could see farther. The world's gentle curve was obvious from this height. If it found nothing, it would not live out another day. There! On the horizon black spore cases popped open. Nitrogen, compressed and pent up all night, blew out the tiny cells locked inside. The plant's shell was as hard as the zand's own night armor, but it was designed to rupture at dawn. Most of the hard seeds fell on barren ground and died. A few spun in long arcs toward the zand. This landed them at the base of the knoll. They instantly burrowed in. Ravenously, ecstatically, they ate. From their positive poles hissed the buoyant lifegas the zand so badly needed. Within their bodies the powerful solvent released by their banqueting reacted with their cell-stuff, yielding other, heavier gases. They split, dividing to multiply. Wriggling, they squirmed deep into the porous foodrock and spread across the rumpled face, their surging mass smothering it in a brown carpet. The zand edged closer, waited for the right moment—and struck. Greedily it sucked in deep savory drafts of the zesty life-giving gases they gave forth. The brown mat curdled and died. The zand's sick weakness vanished. The smoldering furnace of metabolism now ignited, and its fires sent waves of strength surging along its entire body. For the first time since waking, the zand reared fully upright. Its spindly arms shook defiantly at the cold sky. Its chilled mind now fully unlocked. Loudly it trumpeted a hymn of praise to Lightgiver. That majestic Source of all life now floated entirely clear of the curved horizon, still shrouded in rising, swirling blue-white vapors and the driving, big-dropped rain. Something fluttered out of the cloaking mists. A flapper, it must be, riding the turbulent mist currents toward the outcrop to steal from the dawn's wealth. The zand tensed to fight. But it struck the ice, smacking and rolling. The big dark mass came thumping and tumbling to rest at the edge of the foodrock, sending cold steam purling up from where it lay. Dead? More important—new. Strange. Round like Lightgiver, or like the zand itself at night, but smooth, shiny, hot. It even melted the rock-hard ice beneath it. In its polished surface the zand saw itself, grotesquely distorted. Heat was wealth. The zand hungrily reversed its blower-organ and vacuumed the thing into its forward orifice. Then came the first shock. This thing was heavy, throbbing, worse than a large flapper. Dull pain throbbed through the zand's alimentary tract. Its first impulse was to spew the offensive lump forth. But the zand had not survived countless nights to greet Lightgiver by merely obeying its impulses. It hunched closer to the outcrop and scooped up a generous helping of spicy mites. At once their furious body chemistry gave aid to its own. A fuming corrosive kindled in their first digestive stage. This syrup bit into the strange sphere. The shiny skin fumed and bubbled. The zand's inward discomfort transmuted into a heady glow of well-being. Strange, vibrant tastes rippled through its body. Nothing except Self-merge had ever given it such joy. It verged on delirium. Dimly, through a curtain of pleasure, it felt the rain of wobbly drops ease, mists lifting to unveil the hard, hot glory of Lightgiver's face. Ruby melt fluid trickled from warming rocks. Digestion simmering, the zand felt flooded as never before with power and hope. Turning its back to the wind, it sloshed away from the knoll where it had very nearly died. Without a pause it dove into the dawn sea. Waves broke across it, bringing warmth. The sky brimmed with Lightgiver's promise. It was at peace. It wondered where the shiny sphere had come from. Over the horizon, toward Lightgiver. An excellent puzzle to solve on such a fine day. It moved steadily, legs clacking, storing lifegas and burngas from the brimming fresh air. Radiance filled it. Breathing in deeply, it broadcast a rejoicing morning song. 2 CALLING HOME Shanna put on the last movement of Beethoven's Fifth and turned up the gain. Ludwig von Cornball, they had called him back at Moonbase One. Hipitude: post-postmodern irony. All because she played ol' Ludwig so much—but who was more appropriate? What spirit better expressed the grandeur of an expedition to the edge of the solar system? She could well visualize Dr. Jensen tut-tutting at this latest display of childish dramatization. But Moonbase and Jensen—and more to the point, her father, the Great Axelrod—were electromagnetically five hours and twenty minutes away. Physically, even at high nuclear impulse, they were well more than a year away. For now, within the survival limits set by her spacecraft—Proserpina, yes, hers, even if she did have to pretend to egalitarian methods with the crew, her crew—she could do what she damn well pleased. With a happy sigh she relaxed into her hammock and gave herself up to the symphony's triumphant chords. Still, indeed, she was on watch. With a foot she pushed off against a bulkhead and swung slowly in the ship's light centrifugal gravity, eyes on the wall screen. Ludwig had never imagined a place like this, yet the music fit. Pluto was dim but grayly grand—lightly banded in pale pewter and salmon red, save where Charon cast its huge gloomy shadow. Massive ice sheets spread like pearly blankets from both poles. Ridges ribbed the frozen methane ranges. The equatorial land was a flinty, scarred ribbon, rock hemmed in by the oppressive ice. The planet turned almost imperceptibly, a major ridgeline just coming into view at the dawn line. Observers on Earth had thought Pluto, Charon, and the sun could only line up for an eclipse every 124 years—but in 2029, to the utter surprise of Earthside astronomers, both the satellite's orbit and the planet's axis had begun to drift. By the time Shanna's mission launched in 2044, Charon was eclipsing the sun regularly each Plutonian day. Axes were tilting. Whole worlds were spinning up. Strange, but just the beginning, thought Shanna. The game's afoot, Watson. Even from Earthside satellite observatories—forty Astronomical Units away—it was obvious that Pluto was warming. The spectral bands of its nitrogen atmosphere showed steadily rising temperatures, working up toward the heady heights topping 100 degrees above Absolute Zero. (Or more than 300 degrees Fahrenheit below zero, for the American audience; when would they go metric?) All this, despite Pluto's steady retreat from the sun as it followed its 273-year, highly elliptical orbit. Into the far dark. Nobody had expected the warmth. Or the steady intrusion of the interstellar gale, pushing in on the sun's own solar wind. That steady pressure was simply the plasma and gas that coasted between the suns, pressing against the prow of the sun's own wind, as the sun swept through the galaxy in its own orbit, about the galactic center. What the astrophysicists called the pause point—which meant where the solar wind met its equal and fought endlessly—that point was edging in, steadily. Against an unseen pressure from beyond the stars. Why was it coming in? How? Nobody knew. And how typical of Pluto and its moon that they should thus confound Earth's experts—who had warned her that this remote, small, cold world would be dull, the mysteries arcane. Yeah, yeah, yeah: gray, dim, frigid. (Hadn't she had a boyfriend say that once? And he'd been so wrong ...) They—all the astrobio experts, and the outright astronomers, too— hadn't seen any of the mystery here, the magic. Fine, let 'em stay home. Shanna wondered about the glorious filmy auroras. They alone were worth the trip, even though a beetle-browed congressperson from one of the finance committees would hardly have agreed. Had the great, luminous auroras been here before ... well, before what? Nobody had a clue what was driving the warming. Or the steadily incoming pressure. Could the auroras be involved? They were much like Earth's— sheets of excited molecules radiating, stirred by the incoming sleet of solar wind particles. Rut these danced far faster, rippling with vibrant colors, like flapping flags. She let the view absorb her for a last few moments. Each of her fellow crew—the two Kares, Chow-Lin, and Ukizi—had a specialist's fascination in the frigid vistas. But they were asleep, and she had a whole planet to herself. She was not the theoretician of the crew at all—rather, she was mission biologist/medical, a marginal pilot... and now captain. The physicist who had been captain, Ferrari, died in a freak accident while working aft near the combustion zone, with the robots who tended the nuclear engines. They'd lost three 'bots, too, which were harder to get along without than Ferrari, in her opinion, though she kept quiet on that score. A disaster, yes—but despite Earthside's hesitations, she had assumed command, leaving to Jordin Kare the primary piloting jobs. It had been touch and go there for a week, as they drove outward at a steady 0.3 g acceleration. (Hey, maybe they'd pick up a little Mars Effect in the bargain.) That was a huge rate; if they'd had the fuel to keep to it for the whole outbound trajectory, they'd have gotten here in three months. As it was, the mission had very nearly been called back when Ferrari died. It had taken all the sweet-talking she could muster to deal with both crew and Earthside, plus arm-twisting by good old Dad. Never forget that, she thought ruefully. So now, though nobody liked it all that much, Shanna was in charge. Astronaut type, subspecialist in biology and medical, a practical bio degree, though not really primarily a scientist—but a general science fan, yes. Jordin and Mary Kay Kare, they were the real secret strength out here—the tech types who could repair anything but weren't narrow. The rest of the crew tended the big, roaring bulk of Proserpina and didn't take a lot of Shanna's time, luckily. She wasn't really a manager type. The symphony ended with stirring punch. She could not resist the pleasure of slapping her hand down. A heartbeat later a musical chime—rigged by Shanna in protest against the usual peremptory beeping alarms—told her that the data gathered since Proserpina's last radio contact had now been encoded and kicked back toward Moon-base One. She tapped a key, giving herself a voice channel, reciting her ID opening without thinking. "Okay, now the good stuff, gang. As we agreed, I am adding my own verbal comments to the data I just sent you." They had not agreed, not at all. Many of the Pluto Mission Control engineers, wedded to their mathematical slang and NASA's jawbone acronyms, felt that real, live human commentary was subjective and useless. Ephemeral stuff. Let the expert teams back home interpret the data. But the public relations people loved anything that tickled the public's nose. "Pluto is a much livelier place than we ever imagined." She took a breath; always good to have a clear opening statement. "There's weather, for one thing—a product of the planet's six-day rotation and the mysterious heating. Turns out the melting and freezing point of methane is crucial. With the heating-up the mean temperature is high enough that nitrogen and argon stay gaseous, giving Pluto its thin atmosphere. Of course, the ammonia and carbon dioxide are solid as rock—Pluto's warmer, these days, but still incredibly cold, by our comfortable standards." There was the sound bite maybe. Now the technical. "Methane, though, can go either way. It's a volatile gas. Earthside observers found methane frost on the surface as long ago as 1976— anybody remember?—and methane ice caps in 1987. They speculated even then that some of it might start to thaw as the planet made its closest approach to the sun. Well, it did, back in the late twencen— and still does, every Plutonian morning. Even better, the methane doesn't just sublime—as it was supposed to because of the low atmospheric pressure. Nope, it melts. Then it freezes at night. That makes it a life-supporting fluid, in principle." Now the dawn line was creeping at its achingly slow pace over a ridgeline, casting long shadows that pointed like arrows across a great rock plain. There was something there she could scarcely believe, hard to make out even from their thousand-kilometer-high orbit under the best magnification. Something they weren't going to believe back Earthside. So keep up the patter and lead them to it. Their crew had debated how to announce this for days—with no result. So now that they were sleeping, she would. Earthside deserved to know, she reminded herself. It wasn't an ego thing at all. But still... she was the captain. "Meanwhile, on the darkside there's a great 'heat sink,' like the one over Antarctica on Earth. It moves slowly across the landscape as the planet turns, radiating heat into space and pressing down a column of cold air—I mean, of even colder air. From its low, coldest point—the pressure point—winds flow out toward the dayside. At the sunset line they meet sun-warmed air—and it snows. Snow! Maybe I should take up skiing, huh?" It was hard, talking to a mute audience. And she was getting jittery. She took a hit of the thick, jolting Colombian coffee in her mug. Onward— "On the sunrise side those winds meet sunlight and melting methane ice, and so it rains. Hard. Gloomy dawn. Tough weather— and permanent, moving around the planet like a veil." She close-upped the dawn line, and there it was—a great gray curtain descending, marching at about the speed of a fast car. "So we've got a perpetual storm front moving at the edge of the nightside and another that travels with the sunrise." As she warmed to her subject, all pretense at impersonal scientific discourse faded from Shanna's voice; she could not filter out her excitement that verged on a kind of love. She paused, watching the swirling alabaster blizzards at twilight's sharp edge and, on the dawn side, the great solemn racks of cloud. Although admittedly no Jupiter, this planet—her planet, for the moment—could put on quite a show. "The result is a shallow sea of methane that moves slowly around the world, following the sun. Who'da thought, eh, you astro guys?" A slight slam at the astrophysicists, who had foreseen none of this. Who could have, though? "Since methane doesn't expand as it freezes, the way water does, methane icebergs just sink." Okay, the astro guys know that, she thought, but the public needs reminders, and this damn well was going out to the whole wide bloomin' world, right? "Once it freezes, it sinks. So I'm sure it's all slush a short way below the surface, and solid ice from there down. But so what? The sea isn't stagnant, because of what that big ol' moon Charon is doing in its synchronous orbit. As big as Charon is— and as close to the planet as it's gotten since its orbit shifted, big-time—Charon makes a permanent tidal bulge directly underneath it. Think of a big ridge of fat liquid, swarming over the whole planet." Like the Earth ocean tides, she thought. But much bigger, and somehow strange. "And the two worlds are trapped, two dancers forever in each other's arms." Like the Earth-moon system, only Charon's far bigger in relation to Pluto. "So that bulge travels around from daylight to darkness, too. So sea currents form, and flow, and freeze. On the night side the tidal pull puts stress on the various ices, and they hump up and buckle into pressure ridges. Like the ones in Antarctica, but much bigger." Miles high, in fact, in Pluto's weak gravity ... A huge wedge soaring to the dark sky. Marching toward a dim horizon, grinding, grinding. Strange... But her enthusiasm drained away, and she bit her lip. Now for the hard part. She'd rehearsed this a dozen times, after all the arguments with the other crew—and still the words stuck in her throat. After all, she hadn't come here to do close-up planetology. An unmanned orbital mission could have done that nicely. Shanna had come in search of life. Five decades before, in the twencen and its aftermath, the life-is-everywhere advocates had not had any real evidence. Until the Mars-mat discovery in 2018. And the success of the SETI program, picking up a faint message. Then the skies opened. Attention pored over those mysteries, and in turn back on the old problem of communicating with dolphins, whales, and the like. By then there was a whole academic discipline devoted to reading the well-nigh unreadable. Well, maybe that would help the ship coming out now, on Proserpina's tail, with a crew of has-been Marsmat folk. But for now she had different news. The theory and code developed to wrestle with the SETI message's elegant mumbo jumbo was known somewhat condescendingly as Wiseguy. It had discovered that the SETI signal was a repeating "funeral pyre"—left behind to proclaim the wonders of an extinct civilization, thousands of light-years farther in toward the galactic center. Applied to the microwave emissions from Pluto, Wiseguy suggested an intelligent origin. Coherent, ordered emissions, it said—yet a code Wiseguy could not break. Nor could any human. But those signals were refracted and damped by the plasma streams billowing forth from the sun, so the Space Array near Earth got only glimmerings of the Plutonian emission. This was enticing—even convincing—to the converted. The International Space Agency had decided to go full out and send a manned expedition, putting Wiseguy within range. She paused, held her breath almost as if she expected a chorus of sighs, groans, shouts. But the community that had hoped she would find a striking refutation to the nay-sayers—that band was clustered around a view screen an unimaginable distance away. "This isn't a chemical biosphere at all. That's why it can exist." She coughed, excused herself self-consciously from people who would not hear the cough until five and a half hours hence. Then she made her voice more brisk, scientific. "Mind you, the heating is the real point. There's some driver in the whole magnetosphere, and I think we've found it. A current is flowing in from farther out. I'm talkin' way, way beyond Pluto's orbit. Maybe from the Oort cloud—that's the junk left over from the formation of the solar system, out where the comets come from." To her ears this chatty bravado rang false, but maybe it would play better back Earthside. "We've detected some pretty huge currents in toward Pluto. And little old Pluto packs a wallop, too. It's got a strong magnetic field, nearly perpendicular to its spin axis—we sent you the data on this already. It's a generator, like Uranus. And out here in this neck of the woods, any energy source is big news." She stopped, sensing the skepticism these last sentences would provoke six hours from now. She sighed. This was even harder than she'd feared. Her mind kept lurching off on tangents, spilling out scientific data and ideas. Behind the facade she was a fountain of emotion. Could they tell? She took a deep breath and changed the subject. "And in the atmosphere there's a lot more free hydrogen than a planet this little ought to be able to hold. At some spots on the dayside we've measured gaseous carbon dioxide, although it all ought to be frozen. There are also some strange spectral lines—" Shanna caught herself before saying what those lines seemed to show. She was not ready to make that leap of faith; not yet. "Anyhow, since my last report to you I have sent down one of the smaller probes. It landed on a little hill, one about to be submerged by the just-melting methane sea's froth. Smacked down next to an ice crag which I'm pretty sure is ammonia and carbon dioxide. Telemetry will tell all. The probe reported to me faithfully until an hour and a half ago, and then..." She paused to gather up her courage, imagining her father's famous Axelrod rumbling, avalanche-on-the-way belly laugh and Dr. Jensen's deep-grooved frown. Even though both her mentors were more than 6 billion kilometers away, they were with her as she framed her next sentence. Taking a deep breath— "And then I—I believe something ate it." 3 THE WAY OF THINGS Slanting long in pale shades of crimson and violet, Lightgiver's rays broke through thinning, rosy methane clouds as the rains of morning slackened. Still the zand swam tirelessly on toward Rendezvous with the others of its kind. Joy! It had not felt this strong for many, many long days. Vigor and potency throbbed through it. When it found another of the zand and they Self-merged—as usually happened before day's end—there might even be a Birthing this time. How wonderful that would be! Sudden, tearing pain lashed at the zand's belly. The hooked head of a borer twisted into the hole it had gouged. Agony lanced up from the wound. The borer's tail whipped the red sea into foam, powering the parasite's body around and around and in, in, deep and terrible. The pain soared, and the slow, seeping faintness began. The zand's automatic neural defense system took over. Lifegas and burngas sighed from its side compression chambers into its central canal. A neural impulse connector parted, zapping a spark. Lifegas and burngas ignited in a jet of searing fire. The zand lifted up and away, out of the sea. The borer clung on, its narrow winding body writhing and lashing against the much larger zand. The living rocket left a trail of ivory, a plume freezing into ice crystals. The zand rose. Air pressure dropped, sucking the borer from its hold. It fought and held and then tumbled away into the sea. The zand struggled to breathe, to live. Air rushing past soothed the seeping wound. Lightgiver be thanked for fast reactions, the zand thought. It trimmed its course to swing back down toward the sea, feeling strength return. It was still charged with the rejuvenating energies, sucked from the strange thing it had eaten earlier that morning. The land below lay rumpled and veiled by the dawn's mist. The zand was tempted to remain airborne. Fly! You live! Fly! But it would need its lifegas later on, should there be no food at Rendezvous. By now most of the rockfood on the dayside was submerged beneath the lapping sea of warm red methane. But later the sea would die, going sluggish and then rigid with cold—as it always did. The day would warp on and wrap up into night, leaving the methane to freeze again, promise denied. Only the surge of tides could stir it. And even that was pointless, without real warmth. Such was the Way of Things. Peace lay in resignation to this truth. Again it sang a canticle to Lightgiver, weaving strand-songs in with its general praise. To the almighty Nourisher of the World it gave its own specific thanks at having been spared for further life. The zand vowed to the sky that it would teach young zand to revere Lightgiver's holy name, should Lightgiver see fit to grant it a Birthing. It banked on vagrant winds and sang. Ecstasy. Banked and sang. A faint voice interrupted its meditations. The zand responded with its own distinctive pulses, rip-rap-tink, and received in return a conversational rush of joy from another zand. Old One had evidently survived the night again. Old One—there, in the dark sky. By mutual agreement both zand sealed themselves in firm raps of closing membranes. They expended enough of their precious lifegas to lift and float them just above the surface of the sea, resting. "I am glad you have survived another day," the zand began, as was proper for a younger person to say. "And I also, that we greet one another, You the Younger. We may not look forward to an indefinite number of such days," Old One replied. "Am I always to be the Younger?" the zand asked. "Relish it," the Old One said. "Such a name does not come again." Life on their ever-changing world was precarious, but Old One's tone implied something far more comprehensive and profound. In the Younger, intellectual curiosity—with an undernote of fear—prevailed over the deference due to age. "Explain," Younger begged. They hovered over the lapping sea. Winds snarled, buffeting them. "Think back, youngling. Think back to your last Birthing. How did Lightgiver look in the sky?" The young zand pondered. Self-merge and Birthing were such all-absorbing experiences that one did not, at the time, pay much attention to one's surroundings. Not even to Lightgiver?—the zand's conscience prodded, and a twinge of shame filled it for its evident lack of devotion. And then it remembered. "Lightgiver was brighter—and wanner—and ... and..." "And larger?' Old One prompted. "And larger, yes. A bit." "Now let me share something with you before I die." Old One brushed aside its companion's polite protests. "No, no— listen! I cannot go through many more days and nights of gorge and sleep, gorge and sleep. So attend me while you can, and tell this to the other zand. I am the Old One. Probably the oldest in the world. And I have watched the skies with care. Beyond the cycle of dark and light that we know is a far longer cycle. We have no proper way to measure it. But I have thought this out, and I can tell you that Lightgiver moves in and out, from Its greatest width to Its narrowest. All this great cycle occurs in more than fourteen thousand of our short cycles of light and day. I myself have seen two of these greater cycles." "That much?" Younger was amazed. It almost lost its purchase upon the winds that lofted them above the dawn sea. "Yes—a great long while." "You must have learned—" "I learned this—that while Lightgiver is at Its farthest and coldest, the ice does not melt, and there is no sea, and even in full day all life sleeps." Younger again nearly lost itself upon the winds. This was a dark idea, as black as the world's somber nightside itself. Younger sensed a weariness in Old One's soul, a weight of pure remorseless time itself. So it tried to express cheer: "And then Lightgiver comes back? Yes? And is close and warm, and life wakes again?" "Yes. But in the first of these long cycles—great ages, through which I have lived—we numbered eight thousand zand. We lost some to borers and flappers and starvation, and, of course, each night—then as now—some never made it through to the morning. Once in that cycle came a great raid from Darkside—" "Then! It is—!" "Yes, youngling, the story told in the epic chant is true. Intelligences exist back there, feeding on Lightgiver knows what—and we drove them off in the terrible battle of which legend tells, with much loss of life." "But... the Birthings?" "Almost enough to maintain our numbers. But not quite. And so there remained more than seven thousand of us, lean and hungry, when that long cycle reached the Great Night. When even at full daytime, all freezes." Younger felt awed. "You all... slept?" Looking toward the gathering day, Younger could see broad plains of warming rock, glimmering beyond the methane sea. And in the distance, strange high towers that it could not understand. Could they be a part of this grand narrative, the tale Younger was privileged to hear from the Old One itself? It hoped so. It hoped for some scrap of meaning in all things. "Yes, and Lightgiver shrank to Its smallest size—I assume, for, of course, I could not watch during the frozen time. Then Lightgiver began to grow again, to the point at which It could again give us warmth and zest. But as the second cycle began, fewer of us awoke. How many zand are there today?" The daily Rendezvous ensured that all of them knew. "Yesterday there were 3,441." "Half what there were before the last long freeze. And Lightgiver bestows less warmth and light every day. Your personal experience is that of other zand: Self-merge leads to Birthing only when our world is most warm." "So we do not grow in numbers sufficient to replace ourselves?" "Yes, and then the long cold time takes a further toll. If three thousand of us live until the next great freeze begins, far fewer still will wake for the start of the next warming cycle. Fewer still will see its end. A dark day will come, therefore, when no zand at all will meet at Rendezvous, ever again." Terror shook the younger zand. "And if none of us wake and feed, who will be here to sing Lightgiver's praises?" "The flappers and the borers, perhaps," Old One savagely replied. Then, more gently: "Go, youngling; I have told you. Go to Rendezvous! Tell the others! May you have good Self-merge, with a Birthing and many young. Salute!" With a hiss the young zand deflated, dropped into the sea, and began almost desperately to swim. In moments Younger was gone into the pink dawn mists. Old One had felt the warming, kindling steady and true through the long turns of the world. The past was cold, the future warm. Why? What did those who ruled this world, the gods of darkness, mean by all this? Why the Darksiders, who came to kill so many? Heat was good, bringing life to the world. Warmth was the Good. The Darksiders came always in from the night sky and, once here, killed without mercy. From the Dark came Evil. Why? Buoyed by lifegas, the Old One floated and pondered the many seasons of joy and pain it had seen. 4 DISBELIEF A RED LIGHT WINKED ON: she's here. John Axelrod crushed out his cigar stub, hurriedly shoved it and the ashtray into a bottom desk drawer, and turned up the air circulator. Position had its perks. In a few moments Dr. Jensen would be walking in, and there was no point in adding to the psychiatrist's expectable irritation. To the traditional medical and moral arguments against smoking had lately been added a snob objection as well: tobacco use had come to be associated by Euro-Americans with the tropical world's urban hells, where people still smoked because it was the only pale pleasure they could afford. The sealable double door swung open and Hilge Jensen stepped over the threshold. She was in her hospital whites, not her office wear. As usual, she started in as though they had been only momentarily interrupted, even though it was fifteen minutes since he told her to come talk this out in person. "Look," Hilge said in her quick, flat tones, "consider her personality profile. Smart as a whip, and she paid for it in the usual coinage—isolated with the elite in school, socially a bit slow. Raised by a grandmother because neither of her own parents could be bothered—" "Need I remind you that we are speaking of my own daughter here?" Axelrod kept his voice flat and objective, he hoped. "That's a very inexact description of my family situation to boot." "Well, of course—" Hilge blinked, recalculated. "But I am trying to be analytical—" "Proceed." "Well, she has a problem with authority—" "A mild way to put it." Axelrod kept his face calm, but he sure as hell didn't feel that way. Shanna was his daughter by his second wife—he'd had four wives before realizing that a workaholic life that involved commuting to the moon was incompatible with having a family. Wife number three was a gold digger without motherly instincts, and number four was a beautiful ice queen (what had he been thinking?) who couldn't deal with such a headstrong child. Shanna had ignored both of them, he knew, recognizing that they were likely to be temporary. His mother, the imperious Norma, was the most constant person in Shanna's early life, and eventually she'd gone to live permanently at his childhood home with her. And managed to grow up. No, don't relive that again. Focus. "Very ... mild." She read his expression and hurried on. "So she learned early to live alone, after her parents divorced, the usual problems—live with others and like it." "I know, this." Still objective. Faster to let her run on than challenge everything she says. "Uh, yes. She takes on a late-teenage persona under pressure because that's the mode she used before she started astronaut training. Solitary tech interests, which she covers in social settings with a jaunty air, exuberance masking anxiety—again, fairly standard personality strategy—" "I do remember your reports," he said dryly, still hoping to short-circuit the lecture. Hilge's eyes jittered. "Uh, sure, but we knew she could fit well into that crew. Plenty of leadership skills, well demo'ed in earlier flights—" "And now she's reverted to an old pattern, the bright-eyed-kid personality—I caught it, just listen to that broadcast. Loaded with false voice signatures!" He liked the quick blink Hilge always gave when he used her own jargon back on her. Did she think he'd made billions without having instinctive people-reading skills? "Uh, yes—and along with it comes the early idealism. She wants to find life on Pluto. There aren't any green men or red princesses on Mars, just a mat. So she's bound there'll be something like them on her planet. And when people start acting out their fantasies—" He flared. "You think she's hallucinating?" "She's a long way from home, rest of crew asleep, talking away, tired—" "She's a trained astronaut." He tried to keep his voice flat. "But these descriptions—" Hilge spread her hands, raised eyebrows. "The astronomers say nothing like this is—" "Well, they haven't been there, have they?" He made himself be mild and steady again. "So what're we supposed to do? You can't give her word-association tests when it's five hours between the first word and her response, and another five hours before you can throw her the next word." "Uh, her medication—" "I know you snuck some of your pharm stuff into some of the mission foods." "It was recommended—after long flights—" "So we suggest some menu changes? She'll smell that right away." A pattern he had heard before, drugs as panacea, even the new smart drugs that everybody said were precision, zero side effects. Some damn doctor had even suggested some for himself. He'd stormed out of the office, of course. Alcohol, small doses at the end of the day—that was all the chemical help he needed, thank you. "Mr. Axelrod..." He held a hand up to give himself time to get back to equilibrium. In Hilge's blank look—yep, that's what she was going to suggest next— he saw he would get no help from her. Pluto, he mused, sighing. The name conjured up either horror—the stern, just, and unforgiving Roman god of Hell—or else low humor: Mickey Mouse's floppy-eared dog. Yet Shanna had wanted to go there for so long. Other little girls' idols included holomovie hunks and vid-song stars. His daughter's started and ended with Clyde Tombaugh, the gangly farm kid from Kansas with his homemade telescope who had gone out to the Lowell Observatory early in the twencen and found Pluto within a few years ... with a high school education. Dr. Jensen was only the latest in a long line of psychosnoops who had pestered Shanna all her short life with their why questions. Who knew? Axelrod's decades as an executive had taught that there would never be any clear answers to the deepest motivations, including his own. Maybe especially his own. The rational carapace everybody wore was a shell, and should be left that way. Intact. The problem for those skeptical therapists and soul-probers had been that Shanna was not, and never had been, unfriendly or antisocial. A quick, lithe athlete, she had played on school teams, easily made friends—but on her own terms and not because she couldn't bear to be alone. So the "psychodynamicists" skipped "Why Pluto?" and went directly to "Why do you want to be away for so long?" "She is not following cooperative methods," Hilge said flatly. "She had the rest of the crew dancing to her tune at first. Now some barely tolerate her." Axelrod grinned. People had been barely tolerating him for most of his career. "My daughter! Maybe she's dancing to the music of the spheres." "We must do something." "I repeat: Shanna may be right. Ever think—" The red light came on again. "Hell. That damned new press secretary. He insisted on seeing me before we go on the air." Hilge shifted gears; her voice became low, slow, and grim. "I know. I asked him to be here. Shanna's actions are also, unfortunately, part of a much larger problem. I'll let him fill you in." Press Secretary Harvell Swain walked in with the air of one on a mission. Axelrod hid his grimace behind a palm, faking a small cough. NASA had forced Swain on him in return for clearing away bureaucratic logjams. Axelrod longed for the grand old days when Mars was there for the taking, when NASA was glad to be out of the spotlight because they had muffed their own programs so badly. Mere interplanetary exploration was easy compared with the nasty art of political infighting... Tripping over the threshold on his way through—he was a recent Earthside import, not yet used to lunar doors or the lunar energy-saving walk—he stumbled up to the desk, nodding formally to both Hilge and Axelrod. "I have come here to tell you that the press conference this evening must be called off." "Something the matter technically?" Axelrod countered. "No. But we can't air that report from Astronaut Shanna." "What do you mean, can't?" "Listen—years we've been sweating out this mission. Some politicians are still calling the whole thing a boondoggle, that the Pluto mystery is just scientists playing games. So now the captain says they've found life. In a single-person broadcast!" "Great find, I'd say." "That's exactly the point!" Swain shot back. "So aliens turn up just now? Just when Congress is wondering if the whole issue is a hoax?" Axelrod had seen the usual skeptics making a lot of noise in the media, as excitement grew with Proserpina's approach to Pluto. There had never been data that couldn't be read several ways. The welfare lobby eyed NASA's ballooning budget and made a few phone calls and presto, there were perfectly reputable scientists who didn't believe the solar pause point was moving inward. No threat there, they said. So why all these dollars "sent out beyond Saturn"—as though Proserpina carried tanks full of cash, not water? "You don't really believe any of that hoax stuff, do you?" Axelrod asked with slow calm. "It's too neat! They aren't going to believe her. And if you try to back her up, they won't believe you, either." Axelrod knew the uses of being a hedgehog. He let the clock run. The press secretary subsided, winded. Then he wound himself up for another try. "Look, Mr. Axelrod. I've given this thing all I've got. I laid a lot of groundwork on Earth before coming up here. Human-interest stories about the project, the works. 'Outer darkness defied for a dream by plucky girl and loyal crew'—the works." "Young woman," Hilge automatically corrected. "Sure, but she looks like a girl, face it. And we all know why she got on this mission at all." An uncomfortable silence. Axelrod thought of saying, Sure, the whole world does—because she's Axelrod's daughter. "Saying it aloud here could still be dangerous, y'know." The new robotic microbugs could fly in through the ventilator ducts, crawl in along walls, stow away on an incoming briefcase or trouser cuff. So even in his own office he had to keep his mouth circumspect. Modern times! Swain said nothing, just nodded. Copying the hedgehog strategy? "Okay," Axelrod allowed, "intrepid explorer of our last frontier, check. In the horse race for Truth, Science comes way behind Perceptions." "Exactly. That's what you pay me for." "The taxpayers pay you, not me." "But you can fire me. They can't." "Touché. But you realize, don't you, that we have here more than an oral report? Shanna sent us data, pictures. Plenty of which I have already begun sending down to the New York Times database. Also to the BBC." To Axelrod's surprise the press secretary stood his ground. "And you realize, don't you, sir, that data nowadays can very effectively be faked? That's what they will think down there." So much spunk all of a sudden? What, Axelrod wondered, does he know politically from Earthside that I don't? Time to take the offensive. Axelrod stood up to his full height, which was considerable; a ploy he rarely had to use. "Look, there's this religion that broke away from my own a couple of thousand years ago. It and mine haven't always gotten along. But its founder once said, Ye shall know the truth, and the truth shall make you free. Free! Hell, if we can't stick with that, civilization—scientific civilization—might as well go out of business. We are going on this evening as scheduled, and take our chances with whatever Shanna says." "But it's only, how can I—" "Do it." He stood there and gave them the long, firm look, knowing it would sink in. But he was thinking of years before, when all this had started. Appropriately the desk announced, "Ten minutes." "Dad, I need your help to get on the Pluto mission." Shanna looked at him with that direct way she had, mouth pursed. Objections instantly crowded his mind. God, he was so glad to see her. How long had it been? How many months this time? And now she wanted to do ... what? To cover his confusion, he looked out of the window at the hot July afternoon. Huge shadowy thunderheads were crawling across the sky. All that thick, moist atmosphere out there ... One g made him feel heavy and out of sorts—maybe he was spending too much time off-planet. Or maybe coming back was the problem. She broke into his reverie. "It's everything to me. It's what I've always wanted to do. I've just got to go." He heard a familiar urgency in her voice. Only child ... never gave her enough time ... maybe now I can make up for it. "Dad? It's not like I'm not qualified; you know I am." His mind had drifted from the coming storm outside to the old one inside him. Still, he resisted the impulse to make up for past sins. "What makes you think I can pick the crew? It's an ISA mission, after all." She laughed. "Yeah, and who bankrolls ISA? The Consortium." "An oversimplification. The ISA money is from the big nations." "Who come hat in hand—" "We just got the jump on space technologies, that's all—so we license them to ISA." "Look, Dad, everyone knows there would be no International Space Agency without you. You can't play coy with me." She flashed her engaging, wry smile. The power children have over you ... "You're not testifying here, y'know." "It's too dangerous. There are huge unknowns. Let someone else go." "You sent people to Mars almost twenty years ago; it was even riskier then." "They were all trained NASA astronauts—" She jumped in. "And there was a $10 billion Mars Prize to win." "Do you think I risked their lives for the money?" "Do you think I'm not as qualified as a NASA astronaut?" "You're not an astronaut until you've been through NASA training," he said quietly, "no matter how good a pilot you are." It was an old argument between them. Axelrod had beaten NASA to Mars, but he'd always been careful to use their resources whenever possible. Borrow from the best. Their astronaut training, for example. He hired only government-trained astronauts for Consortium missions. None of the orbital pilots from the little companies. Then the privatization of space that followed the initial Mars landing led to new ways of training pilots. NASA's way was to train people on the ground, then send them into space. As soon as there was ready private access to space, off-planet rocket jockeys could be trained in orbit directly. Better than ground training, yes. Shanna was one of these; a veteran of three years of orbital flights and moon trips. Under an assumed last name she'd worked her way through training and landed a job with Flights to the Stars, delivering tourists and cargo to orbital hotels and moon resorts. It was an old division—like the merchant marine and the navy. She was visibly trying to keep calm. "The ISA has announced an open competition for the crew; it's not just for 'nauts." "And you're going to enter," he said mildly to cover his inner confusions. "Rumor is the Consortium gets to choose one of the crew." "Rumor is rarely accurate. We've agreed to underwrite one." She plunged forward, eyes big. "I want you to pick me." "Do you think I'd risk my own flesh and blood—" "Especially one you ignored for years—" "I had a business to run, damn it." He slammed his fist on the desk. "You were well looked after. I made sure of that." "Dad." There was a tremor in her voice he'd never heard before. Eyes watery. "I've never asked you for favors; never traded on your name. But this is so important I... I need to load the dice." She looked directly at him. "Why do you want to do this? Seems to me you have an interesting life as it is." "The Pluto mission is a great adventure! My job is just"—a shrug— "spacebus techy, medical." "You've never even been to Mars. Go there for adventure! I'll be glad to make that happen for you." "Other people are doing Mars. I want to go where no one has ever been." Axelrod's mind was racing down nervous hallways. If I don't help her, will she forgive me? What if I turn her down and she makes it on her own? Can I make sure she doesn't get chosen? He shook his head. She has such passion for this, how could I? Such idealism—wait a minute... "If you're the Consortium's representative, you'll have to act like it," he said slowly. "Meaning?" "Being a private enterprise, we need to turn a profit whenever possible." "So?" "So if you work for us, part of your duties will be to look for possible revenue-generating opportunities." Shanna looked blank. "You mean—like stuff to sell?" "We'll want exclusive media rights from you, for one." "What is there to sell on Pluto?" she sputtered. "For one thing, the experience. Everyone loves to watch other people in danger from the comfort of their living room sofa. Viktor and Julia have lived under the eye of the vidcams for twenty years. Are you willing to do that?" "I g-guess so." A pause. "Does the camera follow them everywhere?" "In the shared rooms, sure. In the contract. Not in their cabins, though." "Still..." She blinked, as if she had not thought about this part. Just a kid, really..."It must be hell." "It's what you want?" The self-doubt blew away with a sigh. "Yes. Yes." He did what had always worked at crisis points: just let himself follow his guy instinct. Even when it was his daughter. "I'll have a contract drawn up." Her eyes widened, and he knew suddenly that she had not really thought she would win. She rushed around the desk and hugged him, then ran out the door. "You'll never regret this! I promise," she called behind her. Much later, as he was staring moodily out the window, he recalled one of his mother's sayings: "If you love them, let them go." Thanks, Mom. The Pluto Mission Control auditorium was jammed. Newsies, bureaucrats, some lunar tourists who'd managed to get in from the big luxury hotel nearby—Fly the Great Lunar Cavern!—and even a scattering of scientists. All noisy, chattering. A fair fraction of the lunar population seemed to have wedged itself in. Axelrod took a deep breath and stepped out. Applause spattered across the tiered seats as Axelrod came in from stage rear, with an apprehensive Swain a few steps to the rear. Behind them an enhanced image of Pluto as Proserpina had seen it from a million kilometers out filled the large screen. Showtime! Axelrod thought. He hated these and loved them at the same time. Nobody without a streak of showmanship ever got to run a big-time business. Even in its darkest days, with an accountant type as administrator, NASA had put the best possible face on the shuttle-space station debacle. He acknowledged the applause with a short wave of the hand. The cheers were for Shanna, he knew, not for him. He stepped into the chalk-marked area staked out for the holocamera focus. Uncomfortably he became aware of the unseen eyes of Earth's billions a light-second and a half away. "Ladies and gentlemen," he began, "we have exciting news from Pluto tonight. At 10:30 this morning, GMT—which is also our local time here at Moonbase One—we received Astronaut Shanna's latest report. Tonight she speaks to us again, and this time you are going to hear her in person. She's well over 6 billion kilometers away from us. That's 3.6 billion miles for those of you who go in for nostalgia." This line got a ripple of light laughter in the hall, a good sign. He made himself smile. "And it won't be in supersound. But I think we all want to hear what she has to say. His eye caught the second hand of the big wall clock, closing in on a digital readout coming up on 2100, another (and expensive) concession to nostalgia. Timing his last words to end one second before the hour, he said, "All right, Shanna, come in." The words the young astronaut had spoken from Pluto orbit hours before came booming in, overamplified, immediately covering them in a dry wash of static. Damn solar flares, Axelrod thought, becoming once again the electronics professional. Why'd the sun have to get so wild just now? The scientists say it's just part of the long solar cycle, but it's coming on top of all the crackle and fizz from near Pluto. This interference was yet another sign that the bow wave of the solar system was getting pressed back, already close to Pluto's orbit. Understanding this was the second major motivation for going to Pluto. Could such distant events be significant? Or even dangerous? As the interference continued, people stirred restlessly in their seats. Yet the room filled with suspense, for whatever words they could get would be from farther than any human had ever spoken. A voice, if not from the infinite, at least pretty damned close. Though there had been other reports, this one came after the first surface landing. The distortion stopped, the hiss faded. The first word from Shanna that came in loud and clear at Moonbase One and on Earth was, "Life! I'm sure of it!" The woman's fresh, youthful voice exulted. The audience stirred. "I matched every molecular combination in the library memory against it. The Kares both checked me, but they wanted me to make the call, so here I am again, stayin' up late, swillin' coffee, on the phone, callin' home." Axelrod smiled. The homey touch always worked, clear across the solar system. "The only compound that even came close was chlorophyll b. So these are not only plants, they're photosynthetic ones. Back when Pluto was considered more interesting"—she didn't try to keep an edge of sarcasm out of her voice— "some hackers at JPL worked out a series of biochemical reactions that theoretically could work here. It turns out they do. But!—they're not powered by Pluto's distant sun. It's nine hundred times weaker than our sunlight here. There's not nearly enough energy in it." The crowd stirred. This connected directly to the central riddle. Why was Pluto so warm, just lately? And what did this have to do with the data from the Voyager probes, which showed that the interstellar gas and plasma were intruding farther into the solar system? Shanna talked right through the buzz. "The plants combine ammonia ice with carbon dioxide ice and get free hydrogen, carbon, and nitric acid. Presto! Then the nitric acid and the carbon recombine, releasing more free hydrogen plus CO2 and nitrogen—and that's where the animals come in!" Her voice lilted on "animals," and the word sent another murmur through the crowd. "They're methanogens—eaters of methane. You have methanogenic microorganisms on Earth, kilometers down. Since the Mars-mat discovery we've learned plenty about them. They branched off from our chemical forefathers about 3.5 billion years ago. Then they got pushed off to the ecological edge of things—chemical also-rans. Here they're the main show. They recombine the hydrogen and CO2 released by the plants into free oxygen and methane. They store some of the hydrogen in their bodies, and then they can inflate themselves—hydrogen balloons! I watched two of them floating above the sea that way, apparently just passing the time of day." Axelrod smiled. Nobody, not even that idiot press secretary, could believe Shanna was making this up. He had depended on the timbre of her voice. The others had ventured their explanations before the pictures came in. To prove her case, a big glossy picture of two spherical blobs came on the screen. It was at high resolution, and the two hovered over a red lapping background, half shrouded in pink mist. They bobbed and turned in vagrant winds. The room went absolutely silent. Shanna did not. "They also store the oxygen, near as I can tell. And they can combine it with hydrogen, like old-fashioned rocket fuel. I saw one of them escape a predator of some kind by gracefully jetting up through the air, while its exhaust froze behind it and fell into the sea." "Really, now!" snorted the woman science reporter from the New York Times. Axelrod hoped that gibe hadn't gone out on the air to Earth. He would have shot her a frown, but he was still on-camera. Instead, smile, damn you, smile. Like it was some mild joke. With uncanny premonition Shanna's tone turned a shade argumentative. "Yes, a predator. This is evidently a complete, balanced planetary ecology. But I don't think the one that got my first rover was just a beast. From the readings I was able to get before the rover hull dissolved, I think nitric acid ate it. Those low bushes produce nitric acid and the animals don't." Puzzled frowns in the audience. Science reporters they might be, but high school chemistry was going a bit too deep for most. "So the creature that ate the rover was using a plant process, see? Not necessary for its own metabolism. Using it to melt my probe, pry it apart—that's awfully close to tool-using. There's not only life on Pluto—there's intelligent life!" Shanna went right on, her springy tone rolling over the shocked faces in the auditorium. "That's what we've been able to learn by remote observation. Now, obviously, we have to go down there. I'm the captain and the biologist. My job, the way I figure it. By the time you hear these words"—Shanna's voice rose in almost childlike delight— "we'll be on my way to Pluto!" The rows of blank looks would have been funny if Axelrod hadn't felt exactly the same. "I've discussed this with the rest of the crew. Let's say the vote was, um, divided. So as captain I took the responsibility. After all, it's my risk and my field of study. I'm going down, with Jordin as pilot." Her voice softened. "Finally ... good-bye, gang. And especially, good-bye to my dad. He always said nothing could really do more than slow down an Axelrod, and I'm proving him right again. Bye, Dad!" After that, from distant Plutonian space came only a whispering hiss. As soon as the cameras went off, Hilge growled, "You didn't give her permission to do that!" Nobody could hear her rough whisper in the growing hubbub. Axelrod grinned. "And I didn't say she couldn't." 5 A DAY AT THE BEACH The long ICE ridge rose out of the sea like a great gray reef. Following its Earthly analogy, it teemed with life. Quilted patches of vivid blue-green and carrot orange spattered its natural pallor. Out of those patches spindly trunks stretched toward the midmorning sun. At their tips crackled bright blue St. Elmo's fire. Violet-tinged flying wings swooped lazily in and out among them to feed. Some, already filled, alighted at the shoreline and folded themselves, waiting with their flat heads cocked at angles. The sky, even at Pluto's midmorning, remained a dark backdrop for the gauzy auroral curtains that bristled with energy. This world had grown its steadily thickening atmosphere only in the last few decades, the astronomers said. The infrared studies showed warming for maybe fifty years. Yet the gathering blanket was still not dense enough to scatter the wan sunlight, so the bowl of sky was a hard black. Into this slow world came a high roar. Wings flapped away from the noise. A giant filled the sky. Jordin Kare dropped the lander closer. His lean, hawklike face seemed to be all angles in the cockpit's red glow. His eyes moved restlessly over the board instruments, the view screens, the joystick he moved through minute adjustments. Shanna's legs were cramped from the small copilot chair, and she bounced with the rattling boom of atmospheric braking. Beside her in his acceleration couch Jordin peered forward at the swiftly looming landscape. "How's that spot?" He jabbed a finger tensely at the approaching horizon. "Near the sea? Sure. Plenty of life-forms there. Kind of like an African watering hole." Analogies were all she had to go on here, but there was a resemblance. Their recon scans had showed a ferment all along the shoreline. Kare brought them down sure and steady above a rocky plateau, their drive running red-hot. Streamers of steam jetted down onto ice hardened like rock by the deep cold. This was a problem nobody on the mission team, for all their contingency planning, had foreseen. Their deceleration plume was bound to incinerate many of the life-forms in this utterly cold ecosystem. Even after hours the lander might be too hot for any life to approach, not to mention scalding them when nearby ices suddenly boiled away. Well, nothing to do about it now. "Fifty meters and holding." Kare glanced at her. "Okay?" "Touchdown," she said, and they thumped down onto the rock. To land on ice would have sunk them hip-deep in fluid, only to then be refrozen rigidly into place. They eagerly watched the plain. Something hurried away at the horizon, which did not look more than a kilometer away. "Look at those lichen," she said eagerly. "In so skimpy an energy environment, how can there be so many of them?" "We're going to be hot for an hour, easy," Kare said, his calm, careful gaze sweeping the view systematically. Shanna could see what he meant: the lander rested on its drive, and already, pale vapor rose from beneath, curling up past their downview cameras. The nuclear pile would cool in time, but it might sublime away ice beneath them. The engineers had thought of this, so their footpads spread broadly. Hot water could circulate through them, to prevent getting stuck in hardening ice later. They had thought of a lot of things, but certainly not this dim, exotic landscape. The ship's computers were taking digital photographs automatically, getting a good map. "I say we take a walk." They were live straight to Earthside, and Shanna was glad he had voiced the idea first. The mission engineers had warned them to venture onto the surface only when unavoidable. Come this far and never feel the crunch of Pluto beneath your boots? Come, now. The cold here was unimaginable, hundreds of degrees below human experience. In orbit they were well insulated, but here the ice would steal heat by conduction. Their suit heaters could cope, the engineers said—the atmosphere was too thin to steal heat quickly—but only if their boots alone actually touched the frigid ground. Sophisticated insulation could only do so much. Shanna did not like to think about this part. If it failed, her feet would freeze in her boots, then the rest of her. Even for the lander's heavily insulated shock-absorber legs, they had told her, it would be touch and go beyond a stay of a few hours. Their onboard nuclear thermal generator was already laboring hard to counter the cold she could see creeping in, from their external thermometers. Their craft already creaked and popped from thermal stresses. Their thermal armor, from the viewpoint of the natives, must seem a bristling, untouchable furnace. Yet already, they could see things scurrying on the plain. Some seemed to be coming closer. Maybe curiosity was indeed a universal trait of living things. Jordin pointed silently. She picked out a patch of dark blue-gray down by the shore of the methane sea. On their console she brought up the visual magnification. In detail it looked like rough beach shingle. Tidal currents during the twenty-two hours since dawn had dropped some kind of gritty detritus—not just ices, apparently—at the sea's edge. Nothing seemed to grow on the flat, and—swiveling point of view—the ridge's knife edge also seemed bare, relatively free of life. "Maybe a walk down to the beach?" Jordin said. "Turn over a few rocks?" "Roger." They were both tiptoeing around the coming moment. With minimal talk they got into their suits. Skillfully, gingerly—and by prior coin flip—Shanna clumped down the ladder. She almost envied those pioneer astronauts who had first touched the ground on Luna, backed up by a constant stream of advice, or at least comment, from Houston. The Mars landing crew had taken a mutual, four-person single step. Taking a breath, she let go the ladder and thumped down on Pluto. Startlingly, sparks spat between her feet and the ground, jolting her. "Wow! There must be a lot of electricity running around out here," she said, fervently thanking the designers for all that redundant insulation. Jordin followed. She watched big blue sparks zap up from the ground to his boots. He jumped and twitched. "Ow! That smarts," Jordin said. Only then did she realize that she had already had her shot at historical pronouncements and had squandered it in her surprise. And her first word—Wow—what a profound thought, huh? she asked herself ruefully. Jordin said solemnly, "We stand at the ramparts of the solar system." Well, she thought, fair enough. He had actually remembered his prepared line. He grinned at her and shrugged as well as he could in the bulky suit. Now on to business. Against the gray ice and rock their lander stood like an H. G. Wells Martian walking machine, splayfooted and ominous. Vapor subliming from beneath it gave a mysterious air. "Rocks, anyone?" They began gathering some, using long tweezers. Soil samples rattled into the storage bin. She carefully inspected under the rocks, but there was no sign of small life—worm tracks, microbe stains, clues. The soil here was just regolith. "Let's take a stroll," Jordin said. "Hey, close-up that." She pointed out toward movement above the sea. Some triangular shapes moved in the air, flapping. "Birds?" She could faintly hear calls, varying up and down in pitch. Repeating the same few notes, too. Jordin said, "Look in the water—or whatever that chemical is." "Methane? Like molasses." Her eyes widened. On the slick, wrinkled surface, movement. Things were swimming toward them. Just nubs barely visible above the oily surface, they made steady progress toward shore. Each had a small wake behind it. "Looks like something's up," Jordin said. She followed and saw something odd. "Hey! What's that?" A gray arm with a pincer at the end. Gray, lying on the sand. "Looks metallic," Jordin said. There were bits and pieces littering the beach. "Fragments," Shanna said. "Looks like some body, torn apart." They saw other parts along the shoreline, most no bigger than ten centimeters. "Funny," Jordin said. "Might be a machine?" "Probably a species we haven't seen yet," Shanna said. "Gotta get a sample of that." They scooped up a few pieces, filed it away mentally under Mysteries, and walked on. When they came to a big boulder, Jordin took an experimental leap. He went over it easily, rising to twice his height. She tried it, too. "Wheeee!" Fun. And good footage for the auto-cams focused on them from the lander. As they carefully walked down toward the beach, she tried her link to the lander's wideband receiver. Happily she found that the frequencies first logged by her lost, devoured probe were full of traffic. Confusing, though. Each of the beasts—for she was sure it was them—seemed to be broadcasting on all waves at once. Most of the signals were weak, swamped in background noise that sounded like an old AM radio picking up a nearby high-tension line. One, however, came roaring in like a pop music station. "Ouch!" She slapped on filters and then made the lander's inductance tuner scan carefully. That pattern—yes! It had to be. Quickly she compared it with the probe log she'd brought down on her slate. These were the odd cadences and sputters of the very beast whose breakfast snack had been her first evidence of life. "Listen to this," she said. Jordin looked startled through his faceplate. The signal boomed louder, and she turned back the gain. She decided to try the radio direction finder. Jordin did, too, for cross-check. As they stepped apart, moving from some filmy ice onto a brooding brown rock, she felt sparks snapping at her feet. Little jolts managed to get through even the thermal vacuum-layer insulation, prickling her feet. The vector reading, combined with Jordin's, startled her. "Why, the thing's practically on top of us!" She eyed the landscape. If Pluto's lords of creation were all swimming in toward this island ridge for lunch, this one might get here first. Fired up by all those vitamins from the lost probe? she wondered. Suddenly excited, Shanna peered out to sea—and there it was. Only a roiling, frothing ripple, like a ship's bow wave, but arrowing for shore. And others, farther out. Then it bucked up into view, and she saw its great, segmented tube of a body, with a sheen somewhere between mother-of-pearl and burnished brass. Why, it was huge. For the first time it hit her that when they all converged on this spot, it was going to be like sitting smack in a middling-size dinosaur convention. Too late to back out now. She powered up the small lander transmitter and tuned it to the signal she was receiving from seaward. With her equipment she could not duplicate the creature's creative chaos of wavelengths. For its personal identification sign the beast seemed to use a simple continuous pulse pattern, like Morse code. Easy enough to simulate. After a couple of dry-run hand exercises to get with the rhythm of it, Shanna sent the creature a roughly approximate duplicate of its own ID. She had expected a callback, maybe a more complex message. The result was astonishing. Its internal rocket engine fired a bright orange plume against the sky's black. It shot straight up in the air, paused, and plunged back. Its splash sent waves rolling up the beach. The farthest tongue of fluid broke against the lander's most seaward leg. The beast thrashed toward shore, rode a wave in—and stopped. The living cylinder lay there, half in, half out, as if exhausted. Had she terrified it? Made it panic? Cautiously Shanna tried the signal again, thinking furiously. It would give you quite a turn, she realized, if you'd just gotten as far in your philosophizing as "I think, therefore I am," and then heard a thin, toneless duplicate of your own voice give back an echo. She braced herself—and her second signal prompted a long, suspenseful silence. Then, hesitantly—shyly?—the being repeated the call after her. Shanna let out her breath in a long, shuddering sigh. She hadn't realized she was holding it. Then she instructed DIS; the primary computer aboard Proserpina, to run the one powerful program Pluto Mission Control had never expected her to have to use: the translator, Wiseguy. She waited for the program to come up and kept her eyes on the creature. It washed gently in and out with the lapping waves but seemed to pay her no attention. Jordin was busily snapping digitals. He pointed offshore. "Looks like we put a stop to the rest of them." Heads bobbed in the sea. Waiting? For what? In a few moments they might have an answer to questions that had been tossed around endlessly after the Marsmat discoveries. Could all language be translated into logically rigorous sentences, relating to one another in a linear configuration, structures, a system? If so, one could easily program a computer loaded with one language to search for another language's equivalent structures. Or, as many linguists and anthropologists insisted—particularly in light of the achingly slow progress with the Marsmat—does a truly unknown language forever resist such transformations? Shanna stood absolutely still. Those minds offshore might make something of a raised hand, a shifting foot. Not all talk was verbal. She felt the strangeness. Forbidding, cold, weird chemistry. Alien tongues could be outlandish not merely in vocabulary and grammatical rules but in their semantic swamps. Mute cultural or even biological premises wove into even the simplest of sentences. Blue skies Earthside lifted the spirits; here a blue gas might be poison. What would life-forms get out of this place? Could even the most inspired programmers, just by symbol manipulation and number crunching, have cracked ancient Egyptian with no Rosetta stone? Not moving, she sent, "Bring Wiseguy online verbal, now." "Copy you," came word from Proserpina's bridge. Ukizi, from the voice signature. She heard a delicate pop, and there was the burr of background— Wiseguy waiting for instructions. "Hey, guy," she said. "I am not a guy, despite your nicknaming me, but thank you," the program answered in melodious male tones. "We're going to feed you microwave code," Jordin put in. "Make the usual assumptions, as per training protocol number three. Decode in real time." "Now we ... wait," Shanna said, mostly to be saying something. The chill was biting into her feet and hands, and she wanted to move, get blood circulating. "Stay still," she sent to Jordin. "Wiseguy," Jordin said, "can you make anything of those birdcalls?" "Melodic structures, simple," the program said. "Thought so," Jordin said. "Maybe singing is a universal." With the Pluto Project already far over budget, the decision to send along Wiseguy—which took many terabytes of computational space— had been hotly contested. The deciding vote was cast by an eccentric but politically astute old skeptic, who hoped to disprove the "bug-eyed monster Rosetta stone theory," should life unaccountably turn up on Pluto. Shanna had heard through the gossip tree that the geezer was gambling that his support would make ISA bring along the rest of the DIS metasoftware package. The geezer had devoted decades to it, and he passionately believed in it. This would be a field trial nobody could have foreseen. Wiseguy had learned Japanese in five hours; Hopi in seven; what smatterings they knew of dolphin in two days. It also mastered some of the fiendishly complex, multilogic artificial grammars generated from an Earth-based mainframe. The unexpected outcome of $6 billion and a generation of cyberfolk was simply put: a good translator had all the qualities of a true artificial intelligence. As systems got apparently smarter, the philosophers fretted over how to tell an AI from just very fast software. By now the distinction had blurred. Wiseguy was a guy, of sorts. It—or she, or he; nobody had known quite how to ask—had to have cultural savvy and blinding mathematical skills. Shanna had long since given up hope of beating Wiseguy at chess, even with one of its twin processors tied off. "I am laboring, though I must edit and substitute," Wiseguy said. "Okay, just hurry." "There are six transactions capable in human languages," Wiseguy said. "To make assertions, ask questions, issue commands, wish, promise, request. Further, all can be done negatively—" "So? Hurry!" "If there are others that aliens use, I will not even recognize it. I suspect that is happening here. I shall place blanks where I suspect this is happening." "Great—get on with it." She waved again, hoping to get the creature's attention. Jordin leaped high in the 0.1-g gravity and churned both arms and legs in the ten seconds it took him to fall back down. Excited, the flying wings swooped silently over them. The scene was eerie in its hush. No calls now. The auroras danced, filmy. In Shanna's feed from Proserpina she heard Wiseguy stumbling, muttering ... and beginning to talk. Not in English, but in the curious pips and dots of the microwave wave trains. She noted from the digital readout on her helmet interior display that Wiseguy had been running full bore while eavesdropping on the radio cross talk. Now it was galloping along. In contrast to the simple radio signals she had first heard, the spoken, acoustic language turned out to be far more sophisticated. Wiseguy, however, dealt not in grammars and vocabularies, but in underlying concepts. And it was fast. Shanna took a step toward the swarthy cylinder that heaved and rippled. Then another. Careful. Ropy muscles surged in it beneath layers of crusted fat. The cluster of knobs and holes at its front moved. It lifted its "head"—the snubbed-off, blunt forward section of the tube— and a bright, fast chatter of microwaves chimed through her ears. Followed immediately by Wiseguy's whispery voice. Discourse. The big body had small cuplike appendages. Ears? But there were smaller openings below, too, with leathery flaps that moved to track the sound of her footsteps. She guessed the cuplike ones were microwave antennas. On a living creature, she thought, and then put aside her sense of awe. If they were like the human-made mechanical antennas, they could both transmit and receive with them—unlike, say, eyes. Another step. More chimes. Wiseguy kept this up at increasing speed. She was now clearly out of the loop. Data sped by in her ears, as Wiseguy had neatly inserted itself into the conversation, assuming Shanna's persona, using some electromagnetic dodge. To her ears it was just a noisy, spurting stream. The creature apparently still thought it was speaking to her; its head swiveled to follow her. The streaming conversation verged now from locked harmonies into brooding, meandering strings of chords. Shanna had played classical guitar as a teenager, imagining herself performing before concert audiences instead of bawling into a mike and hitting two chords in a rock band. So she automatically thought in terms of the musical moves of the data flow. Major keys gave way to dusky harmonies in a minor triad. To her mind this had an effect like a cloud passing across the sun. Wiseguy reported to her and Jordin in its whisper. It and the alien— Ark—had only briefly had to go through the "me Tarzan, you Jane" stage. For a life-form that had no clearly definable brain she could detect, the alien proved a quick study. She got its proper name first, as distinguished from its identifying signal; its name, definitely, for the translator established early in the game that these organisms had no gender. The zand, they called themselves. And this one—call it Ark, because that was all Wiseguy could make of the noise that came before— Ark-zand. Maybe, Wiseguy whispered for Shanna and Jordin alone, Ark was just a "place-note" to show that this thing was the "presently here" of the zand. It seemed that the name was generic, for all of them. "Like Earth tribes," Jordin said, "who name themselves the People. Individual distinctions are tacked on?—maybe when necessary or socially pleasant." Jordin was like that—surprising erudition popping out when useful, otherwise a straight supernerd tech type. Nobody was going to find an alternative here to Earth's tiresome clash of selfish individualisms and stifling collectivisms, Shanna thought. The political theorists back home would still make much of this, though, she was sure. Shanna took another step toward the dark beach where the creature lolled, its head following her progress. It was no-kidding cold, she realized. Her boots were melting the ground under her, just enough to make it squishy. And she could hear the sucking as she lifted her boot, too. So she wasn't missing these creatures' calls—they didn't use the medium. One more step. Chimes in her ears, and Wiseguy sent them a puzzled "It seems a lot smarter than it should be." "Look, they need to talk to each other over distance, out of sight of each other," Shanna said. "Those waxy all-one-wing birds should flock and probably need calls for mating, right? So do we." Not that she really thought that was a deep explanation. "How do we frame an expectation about intelligence?" Jordin put in. "Yeah, I'm reasoning from Earthly analogies," Shanna admitted. "Birds and walruses that use microwaves—who woulda thought?" "I see," Wiseguy said, and went back to speaking to Ark in its ringing microwave tones. Shanna listened to the ringing interchange speed up into a blur of blips and jots. Wiseguy could run very fast, of course, but this huge tubular thing seemed able to keep up with it. Microwaves' higher frequencies had far greater carrying capacity than sound waves and this Ark seemed able to use that. Well, evolution would prefer such a fast-talk capability, she supposed—but why hadn't it on Earth? Because sound was so easy to use, evolving out of breathing. Even here— Wiseguy told her in a subchannel aside—individual notes didn't mean anything. Their sequence did, along with rhythm and intonation, just like sound speech. Nearly all human languages used either subject-object-verb order or else subject-verb-object, and the zand did, too. But to Wiseguy's confusion, they used both, apparently not caring. Basic values became clear, in the quick scattershot conversation. Something called Rendezvous kept coming up, modified by comments about territory. Self-merge, the ultimate, freely chosen—apparently with all the zand working communally afterward to care for the young, should there luckily occur a Birthing. Respect for age, because the elders had experienced so much more. But respect tempered by skepticism, because the elders embroidered experiences when telling the young the tale of the raiders from Darkside. "And what's Darkside?" Jordin asked. He stirred restlessly, watching the sea for signs that others might come ashore. But the big bodies bobbed in the liquid a few hundred meters away. Wiseguy supplied a guess: "The Outer, they call it also. Perhaps meaning beyond Pluto's orbit? Far into the darkness? There are other possible interpretations I can display in order of descending probabilities—" "That's good enough," Shanna said. "On with it." "Hey, they're moving in," Jordin said apprehensively, mouth working. Shanna would scarcely have noticed the splashing and grinding on the beach as other zand began to arrive—apparently for Rendezvous, and Wiseguy stressed that it deserved the capital letter—save that Ark stopped to count and greet the new arrivals. Her earlier worry about being crunched under a press of huge zand bodies faded. They were social animals, and this barren patch of rock was now Ark's turf. Arrivals lumbering up onto the dark beach kept a respectful distance, spacing themselves. Like walruses, yes. Standing motionless for so long, Shanna felt a sharp cold ache in her lower back. The chill had crept in. She was astounded to realize that nearly four hours had passed. She made herself pace, stretch, eat and drink from suit supplies. Jordin did the same, saying, "We're 80 percent depleted on air." "Damn it, I don't want to quit now! How 'bout you get extra from the lander?" Jordin grimaced. He didn't want to leave, either. They had all dedicated their lives to getting here, to this moment in this place. "Okay, Cap'n, sir," he said sardonically as he trudged away. She felt a kind of silent bliss here, just watching. Life, strange and wonderful, went on all around her. Her running digital coverage would be a huge hit Earthside. Unlike Axelrod's empire, the Pluto Project gave their footage away. As if answering a signal, the zand hunched up the slope a short way to feed on some brown lichenlike growth that sprawled across the warming stones. She stepped aside. Ark came past her, and another zand slid up alongside. It rubbed against Ark, edged away, rubbed again. A courtship preliminary? Something about their movements made Shanna venture the guess. The zand stopped and slid flat tongues over the lichen stuff, vacuuming it up with a slurp she could hear through her suit. Tentatively the newcomer laid its body next to Ark. Shanna could hear the pace of microwave discourse Ark was broadcasting, and it took a lurch with the contact, slowing, slowing ... Then Ark abruptly—even curtly, it seemed to Shanna—rolled away. Its signal resumed its speed. She laughed aloud. How many people would pass up a chance at sex to get on with their language lessons? All along the shingle beach, stretching to the horizon, the zand were pairing off. Except Ark. "Y'know, sex took a couple billion years to evolve on Earth," she said. "Huh?" Jordin's voice sounded surprised. "Oh yeah. Here ... well, how old is this ecology, anyway?" "Pluto must've formed early, from condensation. This could be lots older than us." She muted the furious bips and dots of the Wiseguy-zand conversation. Occasionally Wiseguy sent them a quick term for help— "Is this sensible?" the program asked. "Ontological?" "Hey, is Wiseguy into philosophy already?" Jordin asked. "I dunno what that means." "Ummm. The biology saying is ontogeny recapitulates phytogeny— meaning, in development of the embryo you see the past stages of the species. Once we had gills, back in our fishy days." "Hey, pretty heady stuff," Jordin said skeptically. "So soon?" "Well, Wiseguy did train on the SETI messages." "Seems like it's digging at how the zand see their place in this weird world." "Maybe canned brains are natural philosophers." "Yeah, they don't have sex to distract 'em." They both laughed at that, releasing tension. Here we are, Shanna thought, the Columbuses of a new world, and we're waiting for a computer to do the introductions. "Y'know, I gotta move or I'm gonna freeze," she said. Jordin grunted assent. "Feels great to move. Hey—the zand are moving inland." "Uh-oh. Toward the lander." Shanna walked back carefully, feeling the crunch of hard ice as she melted what would have been gases on Earth—nitrogen, carbon dioxide, oxygen itself. Low-g walking was an art. With so little weight, rocks and ices that looked rough were still slick enough to make her slip. She caught herself more than once from a full, facedown splat—but only because she had so much time to recover, in a slow fall. As the zand worked their way across the stony field of lichen, they approached the lander. Jordin wormed his way around them, careful not to get too close. "Wiseguy! Interrupt." Shanna explained what she wanted. It quickly got the idea and spoke in short bursts to Ark—who resent a chord-rich message to the zand. They all stopped short. "I don't want them burned on the lander," Shanna said to Jordin, who replaced her suit oxy bottles without a hitch. "Burned? I don't want them eating it," Jordin said. Then the zand began asking her questions, and the first one surprised her: Do you come from Lightgiver? As heralds? In the next few minutes Shanna and Jordin realized—all from their questions alone—that in addition to a society the zand had a rough-and-ready view of the world, an epic oral literature (though recited in microwaves), and something that resembled a religion. Even Wiseguy was shaken; it paused in its replies, something she had never heard it do before, not even in speed trials. It was learning not just an alien language but an alien mind. Agnostic though she was, the discovery moved her profoundly. Lightgiver. After all, she thought with a rush of compassion and nostalgia, we started out as sunworshipers, too. There were dark patches on the zand's upper sides, and as the sun rose, these pulled back to reveal thick lenses. They looked like quartz—tough crystals for a rugged world. Their banquet of lichen done—she took a few samples for analysis, provoking a snort from a nearby zand—they lolled lazily in their long day. She and Jordin walked gingerly through them, peering into the quartz "eyes." Their retinas were a brilliant blue with red wirelike filaments curling through and under. Convergent evolution seemed to have found yet another solution to the eye problem. Jordin said, "Y'know, I'll bet these guys can see the sun the way we do." Shanna had been snapping her own digitals. "Meaning?" "Our eyes are tiny in comparison. We're forty times farther away from the sun here, so these quartz eyes are forty or so times bigger. They can resolve the point of the sun into a disk." "Ah. So what's our answer? Are we from Lightgiver?" "Well... you're the cap'n, remember." He grinned. "And the biologist." She quickly said to Wiseguy, "Tell it: No. We are from a world like this. From nearer, uh, Lightgiver." As soon and as tactfully as possible, Shanna got the interchange turned around, so that she was again asking the questions and the zand answering them. Discussing the sun was useful, too. They had a calendar concept of short and long warm-cold cycles that intrigued her. Obviously it corresponded with Pluto's rotational day and centuries-long orbital "year"—an impressive feat of observation and deduction for people who lacked a technology. Shanna soon realized, however, that this idea was new to the zand—that, in fact, it had learned the information that very planetary day from an untutored genius it referred to as Old One. She pressed it further and learned the cold arithmetic. Ark said that this very day Old One had discoursed on such deep truths while floating over the "amber sea." The moment she realized those numbers' implication for the future of Pluto, she broke off. For the first time since she had been a very small child, she blinked back tears. Don't waste our damn time on tears, Shanna sternly told herself. And certainly don't weep in a space suit. But she remained silent, truly at a loss for what to say. Do not sad, the zand sent through Wiseguy. Lightgiver gives and Light' giver takes; but it gives more than any; it is the Source of all life, here and in the Dark; exalt Lightgiver. "Incredible!" Shanna said to Jordin. "Wiseguy must be sending Ark pretty sophisticated stuff." Jordin said, "Hard to believe Ark or Wiseguy can intuit our moods." "And is trying to console us? Or just repeating some, well, theology." Jordin said, "Unless Wiseguy's imposing human categories on Ark's language. Which seems likely—but how'll we know?" Wiseguy told her that the zand did not use verb forms underlining existence itself—no words for are, is, be—so "sad" became a verb. She wondered what deeper philosophical chasm that linguistic detail revealed. "Apparently," Wiseguy said, "we have settled an interesting philosophical question, one that arose with the SETI codes, before I was invented." Startled, Shanna asked, "Which is...?" "Whether all intelligences would use intertranslatable symbol grammars." "Uh, I see." "The answer seems to be yes. That is why I can so readily translate the zand language." "Um." Lightgiver gives and Lightgiver takes. The phrasing was startlingly familiar. The same damned, comfortless consolation she had heard preached at her grandmother's rain-swept funeral. Remembering that moment of loss with a deep inward hurt, she forced it away. What could she say? After an awkward silence Ark said something Wiseguy rendered as, I need leave you for now. Another zand was peeling out Ark's personal identification signal, with a slight tag-end modification. Traffic between the two zand became intense. Wiseguy did its best to interpret, humming with the effort in her ears. "Y'know, I had my doubts about using a program for first contact," she said. "But it's working." "What choice did we have?" Jordin asked reasonably. "We can't sit down here for weeks chatting away at our low, verbal bit rate." "Right. For one thing we'd freeze our asses off." This all became abundantly clear for the next two hours, when Wiseguy consulted them incessantly about ambiguities, context, syntax—the gray areas where human intuition might still outclass Wiseguy's terabytes. The process was wearing, but at least she and Jordin could rove the land and get a feel for the cold twilight strangeness here. Finally Shanna turned the translator off. First things first, and even on Pluto there was such a thing as privacy. Wiseguy had no need to hear frail humans discussing their weaknesses. Jordin, ever the diplomat, began. "Y'know, it's been hours..." Even on this 0.1-g world she was getting tired. The zand lolled, Lightgiver stroking their skins—which now flushed with an induced chemical radiance, harvesting the light. She took more digitals, thinking about how to guess the reaction— "Y'know..." "Yeah, right, let's go." Stamping their feet to help circulation, they prepped the lander for liftoff. Monotonously, as they had done Earthside a few thousand times, they went through the checklist. Tested the external cables. Rapped the valves to get them to open. Tried the mechanicals for freeze-up—and found two legs that would not retract. The joints took all of Jordin's powerful heft to unjam them. Shanna lingered at the hatch and looked back—across the idyllic plain, the beach, the sea slick like a pink lake. Chances are, I'll never be here again. Maybe the high point of my life ... an incredible vista. She hoped the heat of launching, carried through this frigid air, would add to the sun's thin rays and ... and what? Maybe help induce a Birthing? She reminded herself that she was a biologist, here to understand, not take sides ... Impossible. Too bad she could not transmit Wagner's grand "Liebestod" to them, but even Wiseguy could only do so much. She lingered, held both by scientific curiosity and by a newfound affection. Then another miracle occurred, the way they do, matter-of-factly. Sections of carbon exoskeleton popped forth from the shiny skin of two nearby zand. Jerkily these carbon-black leaves articulated together, joined, swelled, puffed with visible effort into one great sphere. She knew—but could not say how—the two zand were flowing together, coupling as one being. Self-merge. Inside, checked and rechecked, they waited for the orbital resonance time with Proserpina to roll around. Each lay silent, immersed in thought. The lander went ping and pop with thermal stress. Jordin punched the firing keys. The lander rose up on its roaring tail of fiery steam. The experience had been surrealistic. Her biology training was shouting all during their time down there, This makes no sense. No life chemistry should work well at such low temperatures. Enzymes might, sluggishly, but no other biological machinery she knew. But the zand played on... Shanna's eyes were dry now, and her next move was clear: I've got to talk to Old One. 6 OLD ONE THEY SPENT A week recovering from the first landing. ISA insisted that they "restart their sleep cycle," which meant rest up. No problem; she and Jordin were exhausted. But recovery wasn't as easy as when she'd been a teenager; they'd expended a lot of nervous energy. Still, she bounced out of the sack the first day back after six hours to find Jordin already back at work. He was fixing some gimpy gear and refitting the lander, filling supplies and kicking the tires. Engineers think of their equipment as extensions of themselves and often take care of it better than their own bodies. They had to be debriefed. Shanna recorded a quick summary, mostly commentary on the real-time data feed they had sent. Jordin grumbled and did the same. There were the mandatory media appetites to feed, too—a contractual obligation. Thanks, Dad. The Consortium's race to Mars two decades back had built an enduring public for space, sold as real-time, you-are-there exploration. As soon as possible, she got beyond Proserpina's daily details and found time to think the easiest way—by pulling extra time on watch. A darkness deeper than she had ever seen crept across Pluto. Night here, without Charon's glow, had no planets dotting the sky, only the distant sharp stars. At the terminator line shadows stretched, jagged black profiles of the ridgelines torn by pressure from the ice. The warming had somehow shoved fresh peaks into the gathering atmosphere, ragged and sharp. Since there was atmosphere far thicker and denser than anybody had expected, stars seen from the surface were not unwinking points; they flickered and glittered as on crisp nights at high altitudes on Earth. Near the magnetic poles she watched swirling blue auroral glows cloak the plains where fogs rose even at night. When Proserpina had first arrived, Earthside openly doubted the images they sent back. Clouds? Open bodies of liquid? Impossible... Despite all their discoveries, the basic mystery had only deepened. What was delivering such heat to the icelands? Shanna turned off the interior lights so she could see subtle shadings in the crust. It was her nighttime watch, by preference. All the crew were asleep but for her. Proserpina swung serenely about the forbidding crescent of a world that made no sense. As a biologist she was adrift on seas of speculation, as vast as the pewter-gray methane lakes that winked where the sunlight struck. The dashboard clock's blinking crimson obediently reminded her that she should have filed another report, but she had skipped it, letting Mary Kay file a nominal status check and mission parameter index. Even billions of miles away there was paperwork. A Pluto day lasts 6.4 Earth days, so by the time Proserpina was fully functional, the zand were just about to wake up again. During the Pluto night Proserpina requested permission to drop small, rugged microwave sensors around the zand gathering areas. Earthside fretted and argued but after a mere several days, agreed. Down they went. Most survived and began picking up zand cross talk. By eavesdropping, it did not take long to find the Old One, because it was the subject of many conversations. Old One proved to be not just old but huge—three times bigger than any zand they had seen. The Old One seemed to be a different kind of creature—though in high-resolution optical observation from Proserpina it did look much like the zand. Or else the zand, like some Earth species, simply kept growing all their lives, so a big zand was an ancient one. Wiseguy was grinding at the river of zand-talk data, steadily incoming from the eavesdropping sensors. The program thought the "structure coefficients" of the microwave banter suggested a sophisticated language and extensive knowledge, both about Pluto and about their own social codes. Very well; but why was it there? Why such intelligence in this oddly barren place? After days of threading through the Old One's conversations they hit a startling level of complexity. Shanna had scanned through Wiseguy's interpretations, and they astounded. Here, all rolled into one, was the Aristotle, the Bacon, the Galileo, maybe even the Einstein of the zand species. Or else it was the latest in a long line of huge intellects, their knowledge handed down through many generations. Shanna immediately requested Earthside's permission to speak directly to Old One. Again delay. Arguments. Some theorists thought that Proserpina had already gone too far in "interfering" with the zand. Unforgivable, one senior biologist proclaimed in a public screed. But then, they'd said the same about interactions with the Marsmat, too. Those who always advocated going slow didn't understand that people who did not live forever wanted some closure in their lifetimes. And that windows of opportunity had a way of slamming shut; ask Leif Eriksson. After more days ISA agreed. Down went a complex microwave relay, positioned near the Old One. Jordin had labored over it, adding a small nuclear thermal generator, packing in layers to insulate the electronics against the forbidding cold. Then Wiseguy made their overtures. The introductions and first dialogues went surprisingly well. It was almost as if the creature were expecting them. Talking to it over microwave proved dizzying. Shanna instructed Wiseguy to stop fidgeting over pronouns—which the Old One seemed to feel were irrelevant— and other such minor grammatical distinctions. She went for the big, conceptual lumps. From the speed and insight of the Old One's answers she felt the presence of a vast intellect. The zand had produced such intricate, quick thoughts! All with no written language or notational system or even a telescope, much less a computer. Any biologist would ask the obvious: where did such intelligence come from? This skimpy environment, with few microbes and almost no fauna bigger than her thumb, seemed inadequate. At least primate intelligence had arisen in a broad, diverse biosphere ... but maybe that wasn't necessary. The Old One was the premier zand philosopher-scientist, and it had the advantage of time. It had lived, if Wiseguy's own beginning conversations with it were right, more than four hundred Earth years. As for how old the zand were—well, the Old One had shied away from saying. Maybe it didn't know. Old One had blithely skipped most of the semantic and conceptual preliminaries she and Wiseguy had gone through with Ark. These guys learn! In fact, the native savant—its bulky, walruslike body already appearing on T-shirts Earthside—shortly had started communicating directly with the Discursive and Integrative System. "Dis" was the Greek equivalent of Pluto, so the project's choice of acronyms was entirely appropriate. Their DIS metaprogram was a superstructure above Wiseguy, tasked with integrating results with the whole architecture of their onboard computing. Olympians, keeping their own counsel, for now. Wiseguy had ceased including Shanna in the interchange most of the time. That would have slowed them down, and Shanna did need sleep now and then. Old One didn't seem to, so the large zand and Wiseguy exchanged sallies of semantic battle without a break. She didn't like this, but that's how advanced systems worked, a century into the computer revolution. Machines didn't bother slow-mo humans unless necessary. And Old One, unlike some geniuses Shanna had known on Earth, had tact. When she awoke and came back into the loop, it had abruptly halted its data rate with Wiseguy. Abandoning what must have been for it a heady conversational brew, it deftly brought her up to date. As soon as she began a series of questions, it knew what she wanted to ask. Yes, it said—her vitamin hypothesis did, after a fashion, fit the facts. The zand suffered from what amounted to nutritional deficiencies. Analogous to Earth species, they needed trace elements for full health and strength, even for survival. The remedy lay, in a sense, close at hand—and in another way frustratingly, tantalizingly far off. That was why Old One had philosophically resigned itself to die in the next few day-cycles. It had readily volunteered this fact, as though they would understand. After all, weren't they also from Lightgiver, or at least in its neighborhood? They knew all, yes? Surely they could tell that another wave of Darksiders was coming, this time to bring a tide of death? Lights often streaked across Pluto's somber heavens. Some of them pounded into the ice or plunged into the sea as what Old One called skystones. As soon as she heard the translated anthology word—a common translators' programming trick, nailing terms together as an approximation—Shanna knew whence they came: the cometary Oort cloud. That great gray swarm surrounds the solar system to a depth of a third of a light-year. Inconceivably vast, its inner edge intersects the orbits of Pluto and Neptune. Pluto, nearer the cloud than Earth and shielded by less atmosphere, is far more vulnerable to hammering by meteoric debris. But something malignant fell from the sky, too, and then roved the surface, killing zand. Shanna's mind had skated ahead of even Wiseguy, slapping pieces of the puzzle together. The zand's life was even more precarious than she had imagined. Only by sheer cosmic accident—or as they would have said, by the mercy of Lightgiver—had a stray comet never pulverized Rendezvous. Or sent a tidal wave to roll over the zand during their breakfasting or at Birthing. She thought about that in light of Pluto's long but odd history. Many astronomers thought it had started life as a moon of Uranus, later liberated by some impact or else by the slow tugs of gravity from some other passing body. Somehow the world had gotten free. Maybe the origin of life here, and evolution, had started then. Maybe. Only by another accident—or miracle; give the zand their nod—had they survived the Oort cloud bombardment— Hey—wait. A lightning hunch, like the ones that had given Shanna a competitive edge during astronaut training, struck her, hard. Evolve? Who said they evolved here? The implications of that were too much for now—she brushed them aside. But one thing she suddenly knew. The zand were metal-based life, almost like machines, but driven by a metallic chemistry. Nobody had foreseen such an exotic chemistry, blending metal's liking for oxygen—like the iron rusts of Mars—and a chilly liquid chemistry of methane. Running low-temperature metabolism demanded rare elements. Churning chemistries had to be fed. Out there in primordial Chaos and ancient Night, in tiny but sufficient quantities, lay the heavy metals and rare earths the zand needed in their food. They harvested these, Old One said, from the skystones. But that raised a practical problem. Most skystones fell into the large methane sea, where at sunset they irrecoverably froze. Or else the skystones plowed into the cliffs and shadowy crevasses on the night-side. Into those frigid lands the awake zand never ventured; they slept through the coming of night. But the fallen skystones then sank into the liquefying ice fields at daybreak. The methane sea came from the ices and so consumed all but a tiny fraction of the vital skystones. She pondered this exotic biology. If a zand was lucky enough to find a skystone at dawn, before the precious stuff sank into the melt—or if it could dive into the shallows, searching for treasure on the frozen shelf... But the chances of that had to be so slender. They had so little time. Shanna reluctantly—for such a mass of knowledge remained untapped in that mind!—bid Old One farewell, through Wiseguy. Which even seemed to sense her mood, and said, "There will be other conversations." Hope so. 7 CRESCENDO EARTHSIDE sent THEM a blizzard of questions. Shanna tired of answering them. She had one of the crew, Chow-Lin, do a downlink transmission because he had the old NASA-style jargon down pat. Alphabet soup, with acronyms back-to-back. The message was that they had "contingency strategy worked out" to avoid "any serious danger," though they were "operating out of" their "planned parameter space." There was no "incremental creep in risk," just their "preplanned" (she always wondered what "postplanned" might be) "spectrum of exploratory responses" to a "knowledge-acquisition-driven expedition" here on the "frontier of humanity." She had always admired the way bureaucracies spontaneously produced leaden prose, blandly sliding from the mouths of people who absolutely believed everything they said. Then they had an all-crew meeting. Around the table the rest of the crew looked grim, like a support group for hemorrhoid sufferers. "We don't understand," Chow-Lin said. "The zand, the Darksiders— what's it mean?" "I want to compliment you on how you handled the public angle." Shanna had taken management courses and remembered to open with a compliment, especially if one wanted to present people with plans they might very well dislike. "Quite adroit." But Chow-Lin wasn't having any. "We don't know what's going on!" Jordin said quietly, "Research is when you don't know what you're doing." Mary Kay looked askance at her husband. "Or overdoing." Shanna asked her, "You think we stayed down there too long?" Chow-Lin said stolidly, with a heavy-lidded blink, "You were hours over nominal." "Hey," Jordin said, "nominal is just a guess, not an order." Chow-Lin was unmoved, lips twisted skeptically. "If you'd had a liftoff failure, there wasn't time to get you up from the surface before you froze." "We made the discovery of the age," Jordin said, still sounding reasonable but his eyes glinting. "That tends to concentrate the mind." Shanna recalled the old Samuel Johnson saying, something like, Nothing so concentrates the mind like a pending execution. She stayed silent while Jordin and Chow-Lin traded gibes, with Mary Kay slipping in worried remarks. Overture ... Then even Uziki, the quiet one, chimed in. Discord ... First Theme. Shanna recognized the tones, listening for the underlying feeling rather than surface content. They needed to get out their vexations, not about the danger of the first landing at all, but about being left out. Therapy time. Now for Second Theme... "Taking chances isn't the same as exploration," Chow-Lin was saying, so she countered, "What were you observing?" Chow-Lin hesitated only a second, nodded to Uziki, who punched a command into one of the big wall display screens, which was at the moment showing surf breaking on a white beach. It flickered over to a 3-D diagram of the vicinity near Pluto, with Charon shown to the side. "We used radar backtracking of incoming masses, as discussed. There is a steady stream"—the screen showed orange dots curving in from farther out—"coming on nearly straight-falling orbits." The dots followed yellow trajectory curves, approaching Pluto and slowing. "Not a free infall, then," Jordin said. "No, in fact, there's considerable slowing on the approach. Then—" The dots entered the thin Plutonian atmosphere, showing flaring trails. "Aerobraking?" Mary Kay asked doubtfully. Chow-Lin nodded. "Yeah—artificial as hell. Somebody's dropping descent packages on the surface, and they're moving slow enough to survive the impact." Mary Kay said, "Deliberately targeted, that's clear—this stuff isn't natural." Shanna wondered for a moment if she had lost her capacity for surprise. So much ... She thought silently for a moment as the others discussed details, and then said slowly, "All those incoming arcs—they end on the nightside." Uziki said, "Yes, I noticed that, too. For some reason—" Jordin said, "Even when their aerobraking trajectories wrap all the way around the planet, they end up coming down at night. Damn funny." Shanna made her leap. "Those are the Darksiders! The zand call them that because they land when the zand are asleep and most vulnerable." Chow-Lin sat back, face impassive. "Ummm, an hypothesis..." "It can't be an accident that the incoming prefer to land at night, when they can't even see the landing zone very well," Jordin said. "Hey, maybe that's why we found pieces of them on the beach—some of them hit too hard and break up." "Maybe a Darkside landing is tied to the biology," Mary Kay ventured, looking at Shanna— Who shrugged. "Could be. Night's pretty damned cold—even for Pluto. All I know from the Old One translations is that the zand are getting decimated by something called the Darksiders. If they're to be believed—and why not?—it's an ongoing genocide." Chow-Lin frowned, fidgeting with a pen. "With the strings being pulled by—" "Something farther out—but what?" Uziki said to the screen, "Full outview." The screen scale expanded until Pluto was a small circle, then a dot. The infalling lines in yellow drew together, making a long, slightly curved band. The scale continued to expand but the yellow just kept going, until— "That's as far as we can track with any resolution." "Wow," Jordin said. "They're from really far out." "No assignable origin," Chow-Lin said crisply. "But their orbits point back to a big ice body." On-screen, a tiny dot got labeled: X. "Got it in the low infrared. It's an incredibly cold place—but warmer than anything else out here, except Pluto." "How could anything live there?" Mary Kay asked. "How can the zand?" Jordin countered. "No question, this is low-temperature chemistry we haven't a clue about." "There's got to be something more." Shanna peered off into nowhere. "Pluto's is an ecology that's thin, far too sparse. No microbes in the soil—I just ran the chem check and micron-level analysis. Now, that's just plain impossible. Biology builds up from the basic building blocks. Here there are none. Just a few organisms and a spotty food supply. No pyramid of life, just a few big fauna sitting atop a set of stilts." "So..." Now Mary Kay looked both skeptical and puzzled. "We're missing something." "Or else our whole comprehension of biology is wrong. You don't build up big creatures without a huge investment in processes, chem, metabolism..." Shanna stopped, frustrated, but knowing what to do next. "Let's leave it to the biologists Earthside," Mary Kay said. "We're explorers, not theory guys." "Right, explorers." Shanna took a deep breath. "So let's explore. I say we go down there and see what the Darksiders are." "Hey, no," Chow-Lin said automatically. "Another descent so soon? I strongly—" "We need to get the full story here," Jordin said. "Not go running home with more questions than answers. We haven't got a clue what is driving Pluto's warm-up, and that is our mission." This was true, but Chow-Lin's expression told them that the argument cut no ice with him. He said, "I think we've gone off the deep end here." Mary Kay, showing some grit in her narrow-eyed expression, said, "We're at the deep end—the borderland of the solar system. It took a lot of money to put us here, and—" "You're going to interfere in an intelligent alien society, don't you realize that?" Chow-Lin said. "We already have," said Uziki, who usually confined herself to computers and the robots. She seldom said anything about nonengineering matters, but Shanna was glad to have her come forward. "They're part of the problem we came to solve, right? So we have to understand them." "We can't just blunder—" "Do I hear echoes of the Prime Directive here?" Shanna said, absolutely straight, letting the words do all the work that a sarcastic tone would have. Chow-Lin was a fan of an ancient TV show, one she had watched a few times. She knew just enough to make fun of it. Chow-Lin said guardedly, "Well, we do have to follow some code." "Look," Jordin said reasonably, "we don't have protocols from ISA on this. So we're free to deal with opportunities as they arise." "You want to go down there again?" Chow-Lin countered. "It's dangerous." "Yeah, but that's not the appeal," Jordin said, only a slight upturn at the corner of his mouth showing that this was ironic. "We don't have permission," Chow-Lin began. "I'll enter an objection—" "No, you won't, mister," Shanna said mildly. "That's an order." She had carefully chosen the moment to invoke her authority. On long missions crew saw their captain sharing the scut work, doing her clothes in the washer, waking up after a bad night's sleep—and soon enough, she didn't look like a voice of authority anymore. But that didn't mean the mission could do without one. It was a matter of knowing when to remind them, a lesson learned through the decades on Mars and passed on. Chow-Lin opened his mouth to say something, then slowly closed it. He shook his head for a moment, biting his lip, and Shanna thought she would have to deal with outright insurrection. But no; he looked down, eyes boring into the black tabletop, and said nothing. Into the silence Jordin said casually, "Y'know, we could use a systems modification. For ... defense." Shanna said, "What?" "If the Darksiders are bent on taking down the zand, maybe they'll come after us, too." The crew rustled uneasily. Shanna hadn't thought of this possibility, and she could tell they hadn't, either. "So how do we...?" "I'll modify the chem launch sequence. Cook up a little surprise just in case." Chow-Lin said, "That's entirely uncalled-for. Not only do we interfere with a sentient alien form, we plan an action against it!" "Technically," Jordin said, "the Darksiders are probably the second sentient form here." This gave Shanna an opening to help firmly defuse the confrontation. "We just don't know—and that's why we're going." She ended the meeting, setting another for the next day. That gave time for the rest of the crew to argue among themselves, of course. Over the next few hours she spoke privately to several of them and massaged the social angles. The Kares, Jordin and Mary Kay, were resolutely reasonable. They took it upon themselves to make the diplomatic arguments that Shanna could not, without appearing weak. They had discovered so much already, yes. The surface was treacherous, yes. The Darkside even more so. Yes. So why go? Because it was their job, and anyway, the captain said so. It took two days of talk and one more of fending off Earthside's alarm. But she went—with Jordin, again. Earthside wanted to use their experience. Shanna knew very little out here, but one thing she knew for sure: the zand were worth protecting. What was that saying? The fox knows many things, the hedgehog one big thing. Okay, she was a hedgehog. Darkside beckoned. She was going to become a meteor miner. Crescendo. 8 DOWN IN THE DARK ISA PLUTO DAILY SUMMARY GMT 0940, Thursday, 12 May 2044 All hands on station: Descent to Pluto Surface Descent Crew: Axelrod, Kare, J. State of Ship • Data systems recycle and purge complete • Thermography and ultrasound integrity check completed 0630 on lander by J. Kare; ready to deploy • Consumables 38 percent above nominal usage rate • Power generation rate 99.67 BOL • Uplink rate maximum of IRSC • Orbital parameters within profile Five-Day Outlook Summary Tuesday, GMT 0900: Lander profiling and resupply Wednesday, GMT 1230: Reactor reshipping by robot teams commences—three-day lining tests and monitoring SUBT Thursday, GMT 10.30: Systems test of optical and infrared sensing Friday, GMT 1100: Wiseguy update and Earthside UBK Saturday, GMT 0300: Mechanicals review and monitor reboot Crew Q&A: Where to begin, guys? Quote for the Day: "Details Are Our Business" The big lander roared as it descended on its steam plume toward Pluto's nighted surface. They took it cautiously, through step-down orbits, pausing at each one to assess the surface and let the detectors have their feeding time. Shanna watched somberly, her chair warming her against the seeping cold here in the planet's shadow. She loved the view this low, skimming. Astronomy's geometries were the essence of smooth beauties—arcs and ellipses, crescents and circles, orbs round and fat in their perpetual, serene dance. This deep range of pockmarked worlds held steep, chiseled mountains that had endured longer than whole continents on Earth. She was gaining now a sense of the deep reservoir of time sleeping out here. But perhaps that sleep was over. The astronomers were used to seeing this deep freeze as a tabula rasa, unwritten upon since the solar system's creation, not as a dynamic realm. But now they knew otherwise. Their nominal mission was a second sampling of the surface, this time on the nightside. Mission goal: to measure atmospheric changes as night came on, and to search for debris from the mysterious incoming orange packages—the Darksiders, presumably. Or so she had argued to ISA; but, in fact, she was seeking the meaning of this place—how it really worked. Too many things didn't add up. "Getting something visible ahead," Jordin sent on comm. "I see it—down below the crescent," she answered. "Not a reflection of a star, either. Too bright." Lights. Brimming yellow dots on the upcoming horizon. Not in the sky; on the ice. A prickly coldness ran through her. In the intense cold below they would have much less time on the surface. ISA didn't want them to do any EVA unless absolutely necessary. Shanna wished she had questioned Old One more fully before charging off this way. The fox knows many things ... Could the zand tribal epic, of the great raid from Darkside in the distant past, be true? But there couldn't, strictly speaking, be any Darksiders. All the planet was exposed to the sun in due course as it rotated. Surely "Darksiders" could come out in the zand's own territory after nightfall, right? And day-living borers and flappers and the zand could flourish on "Darkside" when it faced the sun. Confusing. Maybe a huge mistake in Wiseguy's interpretation. She fretted. Then something like an answer came. As they drove down farther into the night, the reactor in their belly humming and thrusting, a great, sickly greenish yellow arc rose up before her, blotting out stars. "Wow!" And just maybe she had part of her puzzle. Ah. Charon was synchronous in its orbit—the fat gray moon hung perpetually above this area. When the twin worlds swung around into sunlight, Charon—so aptly named after the ferryman of Hades— cast a large shadow, eclipsing the tiny sun. Lightgiver would give even less warmth here than on the opposite hemisphere. This side of Pluto was forever unfavored. It would be far chillier. Even at high noon here methane snow would come drifting down. There was a Darkside, after all. The sun was still four hundred times brighter than moonlight on Earth, she remembered from one of the briefings. Enough to read a newspaper by, but without much atmosphere, all shadows were sharp, hard. Okay, she thought, listening to Jordin bring them down to the preselected landing zone—not far from the odd lights, she noted. The Darksiders prefer to come in out of the night and land in the coldest portion of the planet. Now think like a biologist. Life filled its appropriate ecological niches, as Darwin had seen in the Galapagos long ago. One-half of Pluto was home for the zand; the other was the domain of the "Darksiders." No, damn it! That wouldn't work. She did remember some of the astro briefings she'd had, after all. Viewed from Pluto, Charon had only started regularly eclipsing the sun within the past half century. The astro boys had nailed it finally in 2029, when both the satellite's orbit and the planet's axis had begun to drift. Big surprise. The orbital mechanics had changed. And the waltzing worlds had swung in their crazy, new looping orbits, not giving a damn that the astronomers couldn't figure out why. By 2042, when their mission launched, Charon was eclipsing the sun regularly each Plutonian day. Come, now! Evolution is not that swift, no way. Unless... Unless the strange orbital shift was what had brought the Darksiders out of wherever they hid—hibernated?—for most of Pluto's long orbital year. Shanna shook her head in disbelief. Centuries ago, had Charon's orbit similarly moved to screen out the sun? Are you getting enough oxygen! her nagging inner voice asked. This is strange, even for you... She brushed aside her doubts. Follow your nose, girl. Damn the inner critics. Okay. Did that have anything to do with the odd—but apparently natural—radio emissions that the Space Array had discovered? The whole alarm about the big plasma storms that might be washing into the solar system, if the Voyager data were right? Put that by for now also. Then ... And then Darkside had raided Rendezvous? Old One had said lots about that, clothed in mythic jargon even Wiseguy couldn't follow. The zand, their battle story told them, had barely survived that legendary Götterdämmerung. Or is my liking for Wagner leading me astray here? Twilight of the gods beside a methane sea? Ooooggg... And this time, Shanna suddenly realized, if the Darksiders moved to the lightside within the next few Earth hours, they would catch the greater part of the zand helpless, immobilized in the rosy afterglow of Self-merge. Had that happened before? Probably. Something had built those epic poems Old One recited at blinding, Wiseguy-level speed. The zand feared the Darksiders for good reason. They were both predators, but somehow the Darksiders were even better at it. Jordin was on the comm, passing numbers and "okays" back and forth with Mary Kay on Proserpina. When he had a free moment, she asked, "You're sure the little surprise is ready?" He grinned. "It's too simple to go wrong. Just oxy and hydrogen feeds from our reserves. I fitted two small nozzles and tucked them into a spare cylinder I had, to make a reaction chamber. Just a li'l trick." "Um. Li'l trick." Jordin could rig up anything on short notice, it seemed. "Hope we don't need to use it." "Hey—look there, near our LZ." Jordin pointed. When she looked puzzled, he added, "Landing zone." And she recalled that he had started out as a Marine flyer. "This thermal armor is pretty confining." She felt it pinch at knees and elbows. "I know you think we need it—" "You may be the cap'n, but I'm the safety officer." A nod of the head. "Ma'am." Small lights moved below. Scurrying patterns. "Those look... alive," Shanna said. "Maybe that's the Darksiders." On the attack? she wondered. Hey, don't get ahead of yourself. She repeated her thoughts to Jordin as they descended gingerly, pausing at each orbital level to assess the landing zone. He said, "You got this place figured out already?" "Not really. But something tells me we don't have time to hold seminars on the local biology." He grinned. "Not that I'd attend, y'know." "I know." Shanna's grandmother had dinned into her "reverence for life"—all life. Suppose the incessant motion below was a battle of some strange kind. Could she make a terrible choice, to save the zand? She gritted her teeth. A circle of greater darkness yawned below, breaking the thinly moonlit landscape. It moved; she came fully alert. Quickly she called on Proserpina's computer for data. The temperature differentials DIS could measure in the lower infrared and group into a map. Presto! Inside a minute they had a sketch showing the walls and floor of a deep pit. "Quite patently artificial," she said. "Looks like it to me, and I'm just a physicist." "I thought you were an engineer-pilot." "Hey, physicists can do anything." "Um. So they think. But not biology..." She told DIS to amp the center of the circle, use every pixel. In seconds it did. The screen before her and Jordin zoomed in. Down at the bottom moved blocky somethings, jointed at odd angles, limbs stubby, each outlined in a blue glow. They moved, slow and deliberate. "What's that blue from?" she asked. "Spectral lines say—let's ee—argon." More movement. Ghostly forms, sluggish, as though underwater. Patterns. The jerky, angular shapes were forming into neatly aligned ranks and files, like an army on parade—or a war fleet. "Are those organisms or machines?" she asked. "OP DIS can't tell us without a whole further set of assumptions, I'd say." "I hate to go down there, not knowing." He waved a hand at the starlit wastes below. "Out here do such distinctions even matter?" "Good point. This pushes the boundaries." She frowned. In cold so deep as to be beyond all human reckoning, maybe there were no boundaries. The dim forms were moving into an intricate, ordered array. "Looks like a search pattern," she said. Jordin was busy with their hovering pattern, but in 5 percent of a g there was time to maneuver. The nuke thrummed at their backs, and its plume caught starlight in a filmy gauze. "Maybe they're getting ready for dawn," he whispered. Too many possibilities, Shanna thought. "What are they?" On an inspired hunch Jordin asked DIS to search under "Superconductors." He added, "And match to the spectral lines below." It took only seconds. Good ol' DIS reported. Yes—there were plenty of compounds down there rich in copper and oxygen, and alloys galore. He grinned and said, "Could be that makes them superconductors, at these temperatures." She frowned. "So?" "So—remember those sparks that zapped us when we were walking, last time? There's a big potential difference between the top of the atmosphere and the ground." "Is that usual? I mean, this place is plenty odd already..." She had never had a really intuitive feel for physics, and it was showing. "Not so unusual. Earth's like that, too. When you're standing on the ground, there's a couple hundred volts between your feet and your head. When you walk across a carpet and touch a doorknob, you're just letting electrons from the carpet fibers make their way to the higher elevation. Zap!" He shrugged as though this was obvious. "So knowing that, you never jump when it happens?" To his credit he laughed. "Touché! My point here—this is a guess, okay?—is that energy is available to drive anything that can harvest the potential difference—voltage, I mean. We haven't measured it—I didn't think to—but from those sparks I'll bet it's considerable." "But why is it here at all?" "Umm, good point to you! Pluto turns pretty slow, and that's the ultimate source of the volts—spinning planets with magnetic fields are like generators whirring away in space. Pluto's should be weaker than Earth's..." His voice trailed away in puzzlement. "Somehow the whole place is getting pumped by the electrodynamic weather, you think?" she encouraged him. He gazed at the surface, now so sharp in the stretched shadows of sunset that it looked like a drawing in black and white. "One thing the Voyagers told us was that voltages are trickling in from the Oort cloud's deep freeze somehow. Ummm ... There's that data showing the shock wave in the solar wind. I hadn't thought that could be related." She hadn't paid a lot of attention to the briefings and endless 3-D color visuals about the region farther out. The solar wind speed had dropped near the Voyagers, decades back, she recalled, and the physicists thought that meant Voyager was about to meet a shock wave. The multicolored graphics made it look something like the shock cone riding just in front of a supersonic airplane, causing a sonic boom. That was where the solar wind, which had thinned in its expansion all the way from the sun, finally lost out to the pressure of the plasma that hung between the stars. "That's sure a long way out," she said. "Yeah, but that fast probe, Ulysses, found that the shock's much closer in now than when Voyager found it. They—we—call it a termination shock, and those are great at making fast particles and electric fields." Shanna retreated to what she knew: biology. "There are eels that can store charge indefinitely, I think. Swimming batteries. They use it to discourage predators and stun fish." He looked at her intently. "So being a battery might be a way to keep energy reserves when it's night. Then—those zand could just connect up their internal terminals and—zap!—a quick, sure source of efficient energy. I'll bet it's the same for Darksiders." She sat upright, eyes on the main screen. "Something's flying down there." Small wing-shaped things hovered, then lofted upward together, circling within the pit. Blue lights around the regimented ranks dimmed. "Hard to make them out," Jordin said. "But they're organizing, yeah." "Close-up in infrared," she instructed DIS. A dim view leaped into focus on the screen. Shanna squinted. "They're ... pulling something apart." Something bigger than the moving things. Jordin said, "Looks like they're slicing up a ... zand." Her stomach clenched, looking down at the black ice. "They attack the zand at night. The zand are bigger, but they're sleeping, I guess." The vague forms had pulled pieces away. Quick, scurrying moves. "Let's have a look, okay?" Jordin nodded and started their last deceleration. Zero hour; no more time for dispassionate study and idle speculation. It felt good. He hit the controls. The lander danced up and away, maneuvering above the center of the great pit. Their steam blurred the view. Shanna took a deep breath. The lives below were at risk, and maybe she didn't fathom what was going on here ... but she had to act; it was in her nature. Her pulse pounded in her ears. She had gotten here by following her instincts, the deft feel of intuition. Even if I'll regret it the rest of my life. They could see better. "Yep, that's a dead zand," Jordin said. The shapes nearby moved into a circular pattern. "They see us. Maybe hear us, too—if they have ears." Shanna said tightly, "That li'l trick you rigged up—" "On it," Jordin said. "They're coming fast—" "Man, they look—" "Yeah, dangerous." He put his hand on a little switch on the far side of the module from her. She hadn't noticed it before, and he hadn't mentioned it, either. So I wouldn't bump it by accident? But the call is mine... More shapes swarmed in below. Jordin said very casually, "Y'know, we can't hover forever." "Check. Okay, land in that big broad spot. Looks rocky." "Yep, it is." He took the lander into a bare plain, several kilometers from the Darksiders. They touched down, and the steam plume seemed to blow off the hard ice nearby without even provoking a liquid shimmer. Jordin read off the shutdown protocol, and she echoed it. They spent several minutes checking the engine readouts, relayed the digital package up to Proserpina, and Jordin carefully evaluated the lander pads. "No melting under us." "Good, let's—" Their audio rang with pops. Jordin put their local radar on the big screen. "Yeah, I see it." Dots were converging from all around, making local radar give off a chorus of pings. "Let's get out of here," she said quickly. "Done." He slapped the overrides, and the nuke flared again. A quick burst took them up a hundred meters. "I think," Jordin said mildly, "a professional biologist would label that aggressive behavior." "I tend to agree." Below, gray boxes moved with startling speed. They had rushed in under the lander's plume, meeting just below. They now clustered and dispersed in quick, jerky movements. "Ummm," Jordin said. "Walking washing machines." "More like combinations. Legs that end in wheels. See that one? It's rolling over the flat rock, then steps over the small boulders. Ingenious." "Wheels. Gotta be machines, not zand." "Right. And look, they're extruding pipes out the top." She pointed where a cluster was poking narrow tubes upward. Their steam dispersed quickly, so the boxy forms seemed to ripple. More came in steadily from the sides. There were at least a hundred within view. As the newcomers arrived, they, too, started extending their tubes. "Ummm. Don't like the look of that." "Me, either." She felt a sudden prickle of fear. "Like they were ganging up to ... shoot at us." "That switch?" "Yeah." "Draw them in." She thought, Jordin and I have fashioned an instrument designed for delicate exploration of an alien world ... into a bomb. "Then... do it." Something flickered in Jordin's face. "You—really—" "I know, it's a big step—" "Let's just clear out of here." His lips set firmly, resolved. "We've got to act," she said quickly. He looked at her. "We?" "Okay, me. I'm captain, I'll take the responsibility." He nodded, lips working, then nodded again. "Right. Your call." His thumb touched the jury-rigged relay. He made the lander lower a bit. Darksiders came flocking in from the sides, moving even faster. Shanna felt sudden fear. They were so fiercely agile, and in this deep cold. How could anything— "Should drop some." Tensely Jordin counted. The minicam showed the rocks below growing larger. An instant before impact, he hit the probe's cutting torch. The oxy-hydrogen mixture exploded. A giant yellow fist blasted out of the pit. Vapor boiled up, thick fog condensing at once into glinting crystals. Debris shot far and wide. A shock wave slammed into the lander. The deck rocked. Something solid screeched right through from wall to wall, in and out again. Its passage rang like a giant's handclap. Shanna was in her armor—otherwise explosive decompression would have finished her. In the air around her she saw crystals rattle down in a frigid shower. Air screamed out of the lander. Jordin fought the lander's controls. The vehicle swayed and sank like a drunken express elevator. Deceleration jets sputtered, then coughed out. With a shriek of twisting metal the lander thumped down. Too hard. Three legs groaned and buckled under, canting the deck steeply. Shanna slammed against the wall and felt blood run down one cheek. Her right shoulder hurt, sharp and biting. The silence in the shattered cabin, after so much thunder, seemed eerie. Pluto's cold gases sighed in. She saw her breath frosting over the faceplate and turned up the armor's heater. It gave a wan warm breath at her neck. She breathed in shallow gasps, and the air cut her throat. Her legs were already getting numb. Not much more time. She glanced sideways, stopped. Jordin was sprawled halfway out of his couch, mouth sagging, unconscious. She shouted, but he didn't move. Dead? She couldn't tell if he was breathing. Proserpina rasped in her ear, demanding answers. The cold ... A pouch near her mouth held medication designed for just such a terminal emergency. No pain, the briefers had told her; a bland taste, drowsiness, and then—nothing. She had told them back Earthside to take it out, but after launch she found that it was still there. No, damn it. With blunt fingers she punched in the suit command to call Proserpina on the hailing frequency. "We're down, hull breach, trying to—" Her throat rasped, and her voice shut down. The cold was tightening around her. Her arms and legs moved sluggishly as she got up, turned to the dead command board, then looked at the few screens still live. Movement. A square, bulky object, outlined in cold blue light, lurched past the outside view screen. Noise. Clanking, cutting rasps, thumping. Sudden terror—real, little-child fright at monsters in the dark-— clutched at Shanna's heart. The Darksiders were here. The creeping, aching cold fogged her mind. Some small corner of it still knew nonetheless what it was doing. "Wiseguy! Wiseguy!" Dazed, she got the translator up and running, a hiss in her ears. Outside-direct interface. "Wiseguy ... talk to them," she hoarsely whispered. "Explain..." Talk to them how? Even with the simpler zand it had taken hours of eavesdropping... A section of bulkhead wrenched away. Pale blue light. In through the ragged hole came a many-jointed, metallic limb ending in a ... lobster claw. It groped along the control board. "No—don't break anything!" she cried wildly. As if having heard, the claw stopped. Extended. It jerked forward. The arm swung, extended across the cabin, and touched her faceplate with a sharp click. She blinked. Fast-growing frost crystals framed the claw in an ivory glow. Tired ... cold ... no ... mustn't—not yet. Poking blindly with her stiffening hands, she pawed at the claw. "Wiseguy ... tell them ... Warm..." Shanna slumped. Her icy armor stung her flesh through her padded jumpsuit. Then she was falling through space, into an endless nighted gulf. The ultimate outrage was that a last lucid spark of awareness was able to watch it happening. Down ... down ... down. 9 REBIRTHING Long, slanting afternoon rays stained the cliffs of Rendezvous in soft turquoise and pale gold. The thin air rang to the cracking and clanging of round, dark shells as they opened like great eggs. Old One hovered over the placid sea just offshore, drifting lazily on the welling heat from below. It came alertly out of its meditations and deftly moved toward a stretch of barren rock shingle. There its particular young friend and mate in Self-merge drew apart like giant, slick amoebas. And there, glistening on the sand between them, feebly stirred seventeen splendid zand. Harsh cries clashed in the cold air. Flappers, patiently poised above Rendezvous to wait for Self-merge to end, now folded themselves and arrowed downward. With quick energy it had doubted that it still possessed, Old One flipped over. It pointed its vent apertures at the sky—and fired. The rosy flame lit its plunge. It carved the sky, swooping by the furiously flapping shapes, turning the shrill exhaust on them. Hunger calls turned to thin screams of dying rage. Blackening flapper bodies tumbled and fell to ground. A host of small scavengers raced out to feed on the smoking remains. Baffled, the surviving flappers circled over the beach, readying to strike again. By this time other zand came scurrying into action. They had forgone the bliss of Self-merge in order to stand guard, awaiting Birthings. A furious, snapping air battle erupted over the stony shores of Rendezvous. The little new zand below obeyed the genetic impulse imprinted into them. Like baby turtles on tropical isles, they scrambled down the sterile stretch of beach, searching for something to give them lifegas. Not finding any, they dove with tiny splashes into the sea. There beckoned a gray scum of marine organisms. The floating mites fed on microscopic crystals of ammonia and carbon dioxide, exhaling hydrogen, the gas of life itself. Adult zand flocked in behind the newborn and joined end-to-end in a living wall, fencing off the shallows as a swimming area for the young. One warder on the seaward side cried out as its body took the impact of a borer. Commotion, thrashing. A flapper darted in, nipped off the parasite's body behind the head, and flapped away. "Feed the young some of this!" Old One commanded, jetting toward blue-gray scum. The zand rushed to obey, catching the wrigglers. The young ate, breathed in lifegas, squeaked. Zand warbled gratitude. With great effort the zand and their shellmates struggled up, groggy from Self-merge, and began weakly singing the first notes of the Hymn of Birthing. All along hillsides and ice hollows of Rendezvous, other zand joined in thanks and praise to Lightgiver. But a strange new sorrow gnawed at Old One. It joined, with the quavering of age, in the song, while inwardly it wondered—did Light-giver truly hear? And what did the new beings mean, who brimmed with fatal heat and acted so strangely? Could they be of Lightgiver Itself? Old One had long been certain that Lightgiver did not move across the sky. Instead, somehow it knew that the World in its day turned toward the bright body in the sky, warmed itself, and then spun away again, in endless cycle. Putting together its own thinking with what the hot strangers had said, it now reasoned further—that in the much greater cycle from warm to cold, Lightgiver did not approach and recede from the World. Instead—the thought electrified—the World traveled in a great eccentric loop, first closer to the Source of light and life, then away. Old One basked in thought. So far this was compatible with zand theology and perhaps even strengthened it. Lightgiver was not a wanderer across the sky but instead commanded, the unmoved center of All. The strangers had implied a stunning conclusion—that Lightgiver was, in fact, one of those strange bright points in the sky that multiplied at twilight and grew fewer, thinner at dawn. Now, as it listened to its fellow zand sing chorus after triumphant chorus of the Hymn of Birthing, the eldest of the tribe began to understand why the strangers had been reluctant to part with this stunning information. The strong, simple faith the zand had in Lightgiver, as the knowing, caring Awakener and Nourisher of all life, had carried them since time immemorial through hunger and storms. Through the attacks of flappers and borers. Through the gathering sad and bitter disappointments of dwindling Birthings. And through much else, for cycle after hard, weary cycle. With the new knowledge just gained of their World, they might yet prevail. But Old One decided it would not, at this critical time, share with the others a further revelation that must surely make them falter and despair. Most of the motive essence that sustained them, the strangers had hinted, did not come from Lightgiver at all. The strangers had acted very much like followers of Lightgiver's Way. They had given, freely and without question. They had shared sadness and joy. And they had descended from the black sky, for the zand's sake. They had risked life and in their sluggish way sallied off to Darkside. Old One did not expect the strangers to return from Darkside, of course. Much imponderable evil lurked there. Even those of Lightgiver could surely not master it. 10 HOUSEGUEST Shanna woke. She hadn't expected to. And none of the kinds of afterlife she had ever idly visualized included lying naked in a warm nutrient bath. She let her mind drift... wishing for more sleep ... Then the green, acrid, medicinal-sharp fluid drained out beneath her. She sat up. Not a mark on her; not even, so far as she could tell by feel, a facial scratch suffered in the crash. And internally she felt fine. Ravenous but great. Proserpina's life-support program was passing a test nobody on Pluto Project had ever imagined... Then memory returned. Somehow Jordin had gotten her away from the Darksiders, had kept her alive. "Jordin!" He came in softly, carefully. "You've had a big day." "How long was I out?" "I'd say 'bout seven hours. Mary Kay sedated you so you wouldn't feel the work done on your skin." He frowned, and his lips were set in a firm, give-nothing-away cast she recognized. Withholding something for later, yes. "Freezer burn?" She tried to sit up and look but was still groggy. "You mean frostbite." "That was a joke, Jordin." He didn't smile. "We had to peel you some. Mary Kay did it, not me." "Ummm, yeah, privacy..." But her mind was racing now. "The Darksiders?" "They helped, kinda. I was knocked out, and they resealed some of the joints." "They what?" "Some kind of vacuum welding, I guess. As soon as I could get oriented, I lifted us off." "You were injured!" "Ship operations helped. Mary Kay told me how to use the suit built-in injector, got some stimulant I can't pronounce into me. Everybody helped. We had a little trouble with the pumps. One shut down, dunno why. I'm taking it apart now. Looks like a frozen-up valve, is all." "But you made it! Wow!" "Thought you'd appreciate getting back into a bath." His askew smile was the Jordin she knew so well—never brag, just do the job. But he was hiding something, too. "They repaired things?" "Sure looks like. Vacuum welding ... They're smart." "Yeah. Everybody out here seems to be." "Uh, I've got to get back to work." Jordin left, blushing a bit. Still with the funny set to his lips. She let herself laze about a bit, trying to read Jordin's mood, then roused herself. Time for rebirth. She was stiff, and her joints ached. As she stood to climb out of the tank, a triumphant wave of elation surged through her and pushed all other thoughts and pains aside. Hooray! I'm alive! She set the adjoining shower cubicle for a full, vigorous needle spray and stepped inside. She took it happily, until the water recycler blinked to warn her that she was overusing. Then she let a gush of cold water pour down on her for several seconds before shutting it off. Rather than activate the air-dryer, she stepped out, tingling, and wrapped herself in a huge bath towel. Now you should get some soup into you, her grandmother would have said now. So she did. The chatter with crew was warming, too. She programmed the autochef for one of its most elaborate meals; the ingredients, recipe, and computer routine had been a farewell gift from France, of all places. Preparation burbled happily and she snuggled herself into a fresh coverall. Some astronauts and cosmonauts she had known, when not actually working, adjusted temperature and humidity controls and floated around in their cabins nude. Shanna, however, wore clothes every ship day for much the same reason British colonial officers in the old days, even in the steaming tropics, donned full formal dress for dinner each evening—a connection with civilization. And if crew found out she was doing nudie floats... The autochef chimed; first course served. Shanna turned up the audio and put on the Brahms German Requiem, which, despite its sometimes lugubrious lyrics, seemed to her actually one of the most joyous, life-affirming works ever composed. Crew sat and ate and tolerated her taste, knowing she didn't want to talk. They all had unspoken protocols. "Here on earth we have no lasting abode," she sang, thinking of the Darksiders. She had just killed a lot of them, and yet they had saved her life. And if the zand legends could be trusted, they viciously attacked the zand in the long Plutonian years. And she and Jordin had seen them with a dead zand. She was certain that only her crude bomb had stopped them from doing it again. How to judge? Or was there something deeper happening here? She brought this up around the dinner table, all crew present except the watch officer, Uziki. Shanna was American, so she opened with that. "Would an alien outsider judge America's performance by My Lai and Wounded Knee or by Lincoln and Jefferson?" That got them started. Mary Kay said, "Aren't we getting anthropomorphic here? What kind of consciousness—what kind of ethics—operates with a circulatory system running on liquid nitrogen?" Chow-Lin twisted his lips skeptically. "Or did we get into something we don't have a remote chance of understanding?" Jordin said, "We sure won't unless we try." Shanna let the talk run. She had given the orders, and the others weren't too happy with playing spear-carriers. Fair enough. But democracy was a luxury out here. "There wasn't time for a long discussion," she said. "Somebody had to act, if we were going to keep talking to the zand." Mary Kay said, "Looks from the IR like the Darksiders did pull back after you lifted off. No more feelers out to encircle that zand community." "Um." Chow-Lin looked melancholy, staring off into the distance. "Make a wasteland and call it a peace." Shanna wanted to bark back, "Enough of this nonsense! It's done, so we live with it"—but she held her tongue. Mary Kay said soberly, "We looked at what happened at the, uh, attack site, after you left. Toward local noon, zand came into where you blasted the Darksiders. They ... ate the remains." Shanna gaped, openmouthed. "They feed on..." "Looks like," Mary Kay said. "Tore the body parts down, ingested them somehow." Chow-Lin said, "Remember those parts you and Jordin saw on the beach?" Jordin snapped his fingers. "Darksider parts!" Shanna was awed. Here was a predator-prey relationship, of a weird kind. Maybe, maybe ... Darksiders had the edge in the night, but zand could digest the Darksiders during the day. Overall, the Old One said, the Darksiders were winning. "Speaking as a biologist," she said, "this is making some sense ... but..." She and Jordin gazed at each other, eyes wide. "Current-driven..." he said. "Biosphere," she finished. Jordin blurted, "Enhance the chem reactions with current. Speed up all the enzymes and protein folding..." "To make a chemical biosphere run as though it was a lot warmer," she finished. Mary Kay frowned. "Why? Because whatever built the Pluto biosphere knew lots more about electricity than it did about warm chemistry?" The whole crew stared at each other. "Sounds good," Chow-Lin said. Shanna sat back. Wow. Can that be it? They needed to know more, sure, but she was captain, after all. She should let the research angle rest, get down to business, check out status reports—and then her eyes widened. "Hey, did anybody go down the checklist for the lander?" Mary Kay said ruefully, "We were kinda in a hurry." "Worried about us, sure," Jordin the peacemaker murmured, coming out of his distracted gaze. Something still irking him. A suspicion clicked in Shanna's mind. She said nothing, just jumped up and was first to reach the departure bay. They searched the lander, which was going to need a lot of blowtorch-level work. The alien patch-up had been hasty but remarkably firm and tight. "This wasn't done any way I can figure," Jordin said, running a gamma-ray probe over the seam, which looked like brown, melted ice cream. "Must be low-temperature metal bonding or something." "Spread out all over it and check every crevice," Shanna said tersely. For what? She had no idea. Shanna worked methodically, letting Brahms follow her in her ear patch. Internal systems running okay. Then the external check, looking in every cranny, the underside, wiring boxes, thrusters, and— There it was. A neat oval hole, cut all through the crumpled number four landing leg. Rimmed by an equally neat patch of a dull reddish material. "Red?" Mary Kay said. "Never seen that on the surface." "Only two centimeters across." Jordin took a sample. "Big enough for a clawhold. Maybe somebody hitchhiked aboard?" They stared at each other. "So it's ... onboard?" Shanna mentally kicked herself for not doing this right away. She had been lolling about in a goddamn medicinal bath. Captains don't pamper themselves! The breach was near the lander leg's chunky top swivel joint, which was sitting a mere meter from a bulkhead that cradled Proserpina's life-support tanks. (My God, do they know our ship blueprints, too?) Between the bulkhead and cryo tank compartment the ceramo-carbon deck was scratched and scored, as if something had dragged a heavy machine through. Or a machine dragged itself. A faint tang of—ammonia? What chemistry worked in them?—hung in the air. "Spread out through the whole ship," she said. "We've got to find this whatever-it-is." Darksider. Houseguest. They scattered. She raced hand over hand up one level, to the main ship computer console. An all-systems check gave her nothing. A light winked at her imperiously from one of the monitors. Input for you from DIS, Shanna. Read me! The music ended. Shanna looked at the chronometer: 1700 GMT; nearing the end of the mission's nominal day, but who was counting anymore? Two microwave schedules missed; Earthside must be frantic. She could not yet face playing back whatever worried, subtly reproachful messages they meanwhile might have sent to her. "Mary Kay! Call Earthside, tell them what's up." Ah, the pleasures of delegating. Time to do some hard looking. "It's in the cargo bay," Jordin said tightly over comm. She had been fruitlessly searching for over ten minutes now and saw immediately that he had done the right thing: look where people weren't, usually. The Darksider was smart. And ... why? "Let's circle it," she sent to all crew, and started down to the cargo level. It was there, all right, somehow running at a temperature it could never have evolved for. But then, machines don't evolve... A boxy metal thing, with odd burned-metal spikes, like an angry kitchen appliance. It lifted a shiny, lopsided black claw toward them as they converged. Threatening? No—a scramble of microwave noise came from it, hissed into her ear processor. Talking. DIS sent, It says there is someone who wishes to communicate. "And who might that be?" she said aloud. Heads turned, eyes questioned. The whole crew was here, surrounding the thing. If it exploded, good-bye to the expedition. She gestured for most of them to leave. The Darksider did not move when they did, but she could see glinting quartzlike sensors on each side of it. I am unsure. It speaks very similarly to the zand. I believe they are linked in some fundamental way. "Ummm. Even though they're blood enemies? Why's it here?" To make us listen. To help with the ... converse. "With...?" Those who made this world, it says. "And who's that?" Something ... big. The feed cut out. 11 EVIDENCE OF THINGS NOT SEEN "They are utterly strange." Shanna's voice resonated in the crowded, hushed hall. Axelrod sat at a desk in a capsule above the auditorium where the gaggle of reporters sat, buzzing. He puffed on a cigar, and his very own filter system sucked in the smoke so as not to offend the entire rest of the moon. He relished the pleasure and privilege. His daughter was sending without any visual feed. Probably because she was looking ragged, judging from the high, tight notes in her voice. The reporters caught her anxiety as well. Their eyes narrowed. "Even good ol' DIS is having a hard time making sense out of them, but we've figured one thing out at least. The Darksiders are not native to Pluto at all. They didn't evolve a biology that could go with this planet's chemistry. Instead, I think, they shifted Charon's orbit—in order to make Pluto's daytime under the satellite's shadow more comfortable for them." A rustling of startled disbelief. The briefing room on the moon was overheated and bleak beneath the hard ceramic light, and the crowd of reporters and the snubbed snouts of the media feeds focused on the stage, where Axelrod stood and listened with the rest of them, his face furrowed with doubt and a skating anxiety. Shanna's tones slid through the hushed silence of the room, subdued, distant, coming from billions of kilometers into the long, far dark. "They come from the Oort cloud. That much I'm sure of—the one onboard with us sent a strange, warped—well, I guess you'd call it a map. In three dimensions, in warped perspectives, with weird signifiers we can't figure out yet. The sun's at the far left and down, and whatever made all this happen, it's a lot farther out than Pluto." Another rustle of disbelief. Eyes cast sideways, eyebrows raised. She went on, not knowing how her words would be received. From her tone she obviously didn't care. "And it's clear from all the vector displays and orbits that this has been going on for a long time. It picked up when they started getting our radio signals, I guess, judging from the timeline—if we've read it right. Thing is, Pluto, for them, is a great experiment. By deliberately infusing greater energy than the planet's own low-level ecology had available, they have evolved a sentient native Plutonian life-form—the zand." The reporters were muttering, agitated. "Yeah, I know—evolution doesn't work that way. Well, this is driven. Forced change." More murmurs and grumbles greeted this. "What I'm saying here is that I've recognized what Pluto reminded me of. Grad school! Y'know, when you do those set-piece experiments? Testing simple biospheres-in-a-box, to see how they respond to higher salinity, or heat, or chemical drivers? Pluto is a big lab experiment." An uproar. Scientists and reporters alike jumped out of their seats and shouted. Some shook fists. This is going to look great on vid, Axelrod thought. Maybe we should put these press conferences only on the pay channels. Shanna went on, unperturbed, hours away at light speed. "You tech guys are gonna love this next part! Simple ohmic heating from currents wasn't enough. They're trying to run it all that way, the whole planet, including the borers and flappers—which I haven't even had time to study yet. So much to do!" A famous biologist stood and started to make a speech to the audience, his face red, eyes bulging. Axelrod gathered that Shanna's views insulted not only the man's entire professional career but his culture. Luckily the audience shushed him. "They had to apply the planet's electrodynamically derived currents directly to the 'foodrocks' the native animals consume—and their interference with Charon's orbit has messed up that process a bit. These beautiful auroras are the wastage of the experiment... which may well be failing." Axelrod blinked. This was far more than he could ever have imagined, but already his mind spun with a way to play it. "Centuries ago the Darksiders culled the zand colony of unwanted genetic traits. The zand remember it as a battle, we figure. Remember it with terror and pride—a big event in their folklore. A cold-blooded Darwinian pruning operation, and yes—I'm having real trouble with the ethics of that. For sure. Maybe this whole damned place is a ... well, a luxury. An experiment by beings we haven't even seen yet." Her voice was tight, controlled ... and Axelrod could tell she was on the ragged edge of fatigue. Not sleeping; the ship monitors said so. And from the psychers' feed line, they knew that the crew was worried about her. Sure, they said, she was abrasive and intense, and yet they tried to support her, the captain. Also their only field biologist, who was trying to put the whole jigsaw picture together. But there were limits. Her voice was thin, stretched. Axelrod grimaced. He couldn't do a damn thing to help her. He got to his feet, steaming with energy that had no place to go. "The Darksiders themselves—or Oort clouders, whoever that might be—they've ... well, developed the zand. I'm unclear what's really behind this whole ... project. Their idea seems to be to understand how life can exist on worlds. 'Warmlife,' the Darksider said—but I think it's speaking for something else. That something has tried to bridge the gap. Figuring out life on worlds. Running a big circuit, far larger than planets. Somewhere there's a voltage source, and Pluto's at the other end, the resistor. Ohm's law, big-time. Using electrically generated chemical energy for the ultimate purpose of exploring inward. Toward the sun. Toward us. We are their frontier. And they are ours." This rush of information stilled the room. But only for a moment. A storm of disbelief stirred, faces contorted. Shouts. The noted biologist was on his feet again. "So we can't come back. Not yet, anyhow. That big nuke you're sending out to relieve us—we'll meet them." "What!" Axelrod paced, hands behind back. "She can't just—" And he knew she could. "What happened to us on the surface was first contact, and a very strange one. DIS got us through it. So on impulse—I admit it!—I zapped them, the Darksiders. Then they saved my fool neck, and Jordin's, too. Figure that one out. And now—now, as the only humans in these parts, we're sort of elected as ambassador to Outside. Somehow we've got to open negotiations with them. Or would you like the next contact to take the form of a rip-roaring interplanetary war? With beings we don't know anything about." Axelrod blinked again. In an instant he saw destiny wrapping itself around his daughter like a dark shroud. "Shanna, don't take any more risks. It... it's not worth it," he said softly. Beside him Dr. Jensen spat back, "Shut up. You know it is." For the first time the young, confident voice wavered. "I'm making this decision sound easy. It's not; I'm not that heartless. It's going to be lonely out here. But my crew agrees, and we're staying. Beyond nominal mission duration. Beyond nominal systems lifetime even, if we have to. There are plenty of backups onboard that big ol' nuke you're flying out to us. Extra supplies, tech, crew. We can make it!" Astonished silence in the room. "And there were other things I'd hoped to do. We'll keep on making our schedules, check in regularly. Lots more to do out here!" A long pause, then: "Good-bye, signing off for the crew of the Proserpina," a quickly choked-off breath, and then only the rumble of interstellar noise. 12 A HYMN OF DAY'S DEPARTURE Cold dim SUNSET STAINED Rendezvous in a gray glow. A hard black sea seethed on the far horizon, awaiting the sun's banishment. Icy mountainsides lay clean-picked of any food, save for the fine dusting of brown spores that had settled when the afternoon air began to cool. Out at sea the massed zand, thousands strong, sang the long, lacy Hymn of Day's Departure. The music soared through the dimming air—a multipart canon. As each small group of zand singing its part came to the song's end, it broke away from the larger choir, its members dispersing over the lapping violet sea. The Ark-zand swam steadily toward the setting sun. Lightgiver's rays now streamed through a gauzy veil of storm clouds, and the sea rose steaming with a rising wind. They had lingered too long, the zand feared, their chorus freighted with skittering anxiety. To be caught afloat, when the falling temperature irreversibly triggered its night-change, could well be fatal. Already, the borers had vanished into the freezing deep and the flappers were gone from the sobering sky. And the zand had much to live for now, they knew. The young were quick, eager to learn, zestful. Nearly all of them had survived, thanks to the huge loud vessel from the sky, a miracle. It had killed many Darksiders, leaving their carcasses littering the plains. From these the zand had fed. Even Old One had shed its customary gloom and seemed determined now to live into another day, and many more. Clouds rolled up, towering redly into the sky, obscuring Lightgiver. A freezing blast from Darkside brought the first whirling, spiky crystals of snow. Time was running out. The sea stiffened, readying to turn hard. Lift! Lift! Together, singing, the zand decided to gamble some of their precious fuel reserves. Lifegas flared in orange plumes. They soared steeply up from the freezing ocean. Far off, looming against the oncoming storm, rose the peaks where they had spent their early morning recovery time. Arcing into deft parabolas, the zand swarm drove on hard through the fast-cooling air. Snow came in fiercely, blowing in bitter, blinding gusts. The zand reached their steepled retreat from the long, hard night, some veering, crashing into the ramparts of a crag. Sea level dropped precipitously as the surface fluid froze, shrank in volume, and sank. The groans and shuddering spasms of the daily cycle reverberated low and strong through the sharpening air. Late! We are late! Zand slammed into slopes, tumbled from the gathering air, died in their dozens. But most landed and found shelter. Quickly now the surviving zand drew in masses of the new, loose snow and blew it over the foodrock that would again, as last night, serve as its cache. The foodrock brimmed with fresh energy, gathered from the crackling soil itself. Sparks still jumped when the zand tumbled rocks into place. The foodrock darkened in color beneath a blanket of freshly formed borer spores. The Ark-zand stopped in its calls to the working ranks. Something here was different. The field of black, night-ready spores was broken down the slope by an irregularly shaped mass not made of ice. Lightgiver be praised! The heavenly Provider from the far dark had sent the zand a skystone. And Old One had taught it how needful the skystones were for life. A touch and they carried fresh knowledge into all who would listen. Voices from the Great Dark. Carefully the Ark-zand moved the rough stone up to the edge of the cache and covered it with snow. In the snow blur it did not see through the blizzard's dancing curtains the small, smooth sphere which had guided that skystone down so that it would land on the world gently, without the usual ice-shattering explosion of hot vapor. Nor did it know that the Earther it had met that day was at that moment alertly monitoring the little probe, drawing it away from Pluto's weak, icy grip. Sighing, the Ark-zand settled into the grateful embrace of sleep. It felt a last crackling surge of energy as a current ran down from the sky and found waiting conductivity in the nearby rock. So it would be through the long night. Currents flowed, storing energy within intricate chemical balances. Though this voltage spike came from immensely far away, in thin trickles of electrons streaming across magnetic fields, to the Ark-zand it simply came from the sky in a prickly, delightful gust. All such gifts were from Lightgiver, it thought. Or else from the Far Dark, where legend said greater entities lurked. So much to understand! The two rulers of the sky, a point of fierce light and the opposite realm of vast dark, were the twin poles of a world that did not need explanation. Creation simply ... was. As it ebbed into restful calm, it issued one last humble prayer of thanks. Creation simply was. 13 POST FACTO JORDlN GOT RIGHT TO the point. He rapped on the door of her cabin and sat in the only other chair. Crisp, efficient. His mouth not canted at that odd friendly angle anymore. Looking determined. "Mary Kay and I have been talking." "Yes?" "You nearly got us both killed down there." "You got us out, though. I'm recommending you for special recognition by—" He shook his head, two quick jerks. "We can't be taking risks like that." "Just being out here is risky—" "I'm here to notify you that as per ship's regs, and contractual constraints, I'm filing a complaint with ISA." He said this in a flat monotone, memorized. He had probably written it out. "Oh?" Clearly he had planned to leave it at that, but he was tempted to say more, tongue darting over his lips. "The whole idea was just plain asking for trouble." "I'm not going to debate my decisions, especially post facto." "Earthside says you told them we crew had all agreed." "As I recall, I said you would agree. When you had thought it over." He slammed a palm on her desk. "That's what I mean." "Jordin, I wasn't trained to be captain. I'm just making do." "Not doing too well, either," he said sullenly. "A captain isn't always right." "And crew always has a right to their own opinions." "True—but they don't have a right to their own facts." "We don't think all these ideas hold up." She shrugged—an effort, because her whole body had gone rigid. Tired. "Maybe they won't. That's research." "Okay, fine, your privilege. Just thought I'd tell you. It's Earthside's matter now." "Thanks for letting me know." His eyes darted around the room, not looking at her, acutely uncomfortable. "You bet." Then he was gone. She barely had time to think about that when a beep told her an incoming vid was ready, defragged. She called it up on her cabin screen, and it was from Dad. No tag title, just Axelrod the Great popping up on the screen, wearing slacks, blue shirt, auburn sweater. From the moon, in his personal study, fake digital fireplace crackling with flame in the background for the homey touch. Personal message, the sub tracker said. Uh-oh ... She paused it, got a glass of wine to brace herself, and watched. "Hey, honey, you've got the whole world agog down here. What discoveries! As incredible as the zand vids are, the Darksiders are simply mind-blowing! Some kind of superrobots, they look like. I've—the Consortium has—gotta get some. Just think of what their tech will mean down here. Miles ahead of anything on Earth. Asteroid mining will be a cinch with those babies. Proserpina may be ISA, but High Flyer is ours, and there's plenty of room to bring back interesting cargo. I'll tell their crew to get ready." Shanna suppressed a retort—no sense talking back to a recorded message. "Sorry, got so excited about all your great work, I forgot to say how really worried I was about you. Don't take more chances than you have to; you're still my little girl. Pretty dangerous stuff." He paused and nervously shifted in his seat, eyebrows lifting. "And, ah, rumor is, your crew may be thinking the same." Hmm. What does that mean? Jordin? I'm gonna be replaced? And Dad kinda agrees with him? Even across a billion miles the rumor mill churned away—at light speed. He rushed on. "I know, the Darksiders are alien and strange and all. But they're machines, right? Got to be some patent opportunities there. They work in cold and near vacuum. Nobody here can figure out how. Honey, you said there wouldn't he anything to sell on Pluto, except the story of going there. Not so! You just found it. Or found them—great name, too, the Darksiders. I can see a vid series, just using the title." She groaned and slapped the pause switch. I'll watch the rest later—if my blood pressure goes down. Viktor and Julia! The First Couple of Mars! Coming in with a huge shipload of Consortium types, probably ready to strip the landscape. Gee, Dad, I can't wait. She was suddenly drained. She closed her eyes and drifted into a dream of electric-blue shapes with giant claws rushing toward her... 14 THIS IMMENSE VOYAGE LATER, Shanna SIGHED and stretched in the spaceship's comfortable pilot chair. Again she was watch officer while crew slept. She liked it this way. Earthside would come through in a few hours with their response to Jordin's filing. There would be weeks of messages slinging back and forth. Tedious, disheartening, divisive ... she could see it coming. Jordin might prevail. She had to admit, he had a case. She had a lot of respect for Jordin Kare. But ISA didn't like dissension, especially endangering this high-profile mission billions of kilometers away. Word would leak, and their political stock would take a dive. ISA was the role model for international cooperation; failure would echo around the globe, amped to the max. But that was hours away, and now she had this last watch to stand by herself. Bliss. There was even coffee. Time to take stock, girl. The lander was a wreck, but Proserpina's resources could put it back together. Weeks in the machine shop; do them all a lot of good. Meanwhile, the sole remaining probe functioned with grace and precision. And so would she. Proserpina—Pluto's bride—had a mother named Ceres, she recalled from the background briefings, a goddess of the growing grain; whence the word "cereal." The daughter ended up stuck in the Underworld six months out of every year, which she guessed was the way the ancients poetically figured when to get their crops in and when to plant again. Shanna, as she indirectly helped the zand bring in their harvest, did not want to be similarly mythologized. She wouldn't communicate directly with the zand, at least not right away. They were going to have a severe enough intellectual revolution as it was, when the impact of that single meeting on the shore sank in. The price of progress is often pain. Let them thank Lightgiver, not the Earth interloper, for this gift from heaven. Strange, wasn't it, how human and zand music, religion, and ways of caring so often paralleled each other? Or did that simply show the limitations of DIS and all semantics? Through her gray fatigue she let her mind idle. Could she introduce into Darksider ethics the revolutionary notion that other sapients, even if less bright than oneself, ought to be treated not as means, but as ends? A huge leap. The psychologists said humans learned that in childhood, only through tit-for-tat social games. Well, maybe that could work here, too—if there was time. And there wasn't a lot of time before the big nuke rocket came swarming up here, bringing more opinions... Speaking of ends and means, Earth's self-appointed diplomat reflected, she had leverage; Proserpina had physical capabilities the Darksiders could not fathom—which she could give or withhold— Careful there, girl. "Sleep well," Shanna said toward the twilight view, where the zand were bedding down. Now the hard part began. Her fingers danced over the probe controls. The little globe bobbled and bowed, then shot toward the Darksiders' domain, now enjoying its pallid day. Alone in a world of unrelentingly hostile cold and ominous dark, she was, without noticing it, supremely tired and hugely happy. That this last outpost of the sun had, however improbably, harbored life. That all the smug scientists had been wrong. That this grand mystery was just the beginning of an even deeper one. She was a biologist, trained in the conventional litany, sure—but she knew when to abandon cherished beliefs. Some guiding hand had stitched together low-temperature chemistry and the tenuous energies of electron flow, knitting here a gossamer, lively web. Who? Why? To some godlike purpose? Shanna mused about the lives she had blasted to oblivion, so quick in her certainty. Had those dim mechanical forms been truly alive? Definitions, her grandmother once said, had to be like a fat man's belt—big enough to cover the subject but elastic enough to allow for change. Out here life clung to the last vestiges of possible chemistry. And she was sure, now, that evolution alone could not have forged such an intricate ecology, with so few species—not even in the 4 billion years Pluto had spun. The topsoil samples they had brought back had yielded nothing. If Earth or even the dimmed ecology of underground Mars was any guide, life found myriad small species to kindle. Larger forms stood upon a huge, broad pyramid of microbes beneath. Bare stony soil could yield little. Yet the zand, the Darksiders—they were like cartoons of life-forms. Woven from what? Those things in the pit were not forged from nature's relentless mill, for they did not know anger. They had not wreaked vengeance on her and Jordin when they had the chance. Instead, they had saved them both. For a moment Shanna pictured the Darksiders at the opposite extreme, as saints, but that, she knew instinctively, was also wrong. They were, finally, constructions. Theoretical models. More like robots than organisms, but way ahead of Proserpina's 'bots. Not machines, perhaps, but something that stretched the definition of life and probably broke it. She let her intuition rummage around a bit... Yes. The Darksiders were agents of something larger, something feeling its way, something ... dispassionate. But what? Pluto orbited in its elliptical sway at the very verge of that realm where chemical reactions could proceed sluggishly. Beyond here lay a black abyss in which the seemingly fragile bonds between molecules would not crack before the weightless hail of sunlight. They congealed in the unending cold. In that dark kingdom only electricity could race and flow, to bring motive meaning from the potentials and gravid capacitances, hanging in the vast vacant spaces. There, beneath distant star gleam, gossamer-thin sheets of electrons drifted silently before the subtle tugs of inductances, in vast circuits that light itself could barely span in a full day. She shook her head, trying to see... Biologists think in terms of slow, blunt chemistry. Out here there might be instead the rule of electrodynamics, proceedings only a tiny fraction slower than light. Intelligence set free from molecular torpidity could dash across immensities, unchecked by all but the gritty limits of matter's innate resistance. There the speed of light was the natural speed of events. Of thoughts. Something had made use of these truths, some brooding intelligence hitherto unsuspected, though the basic laws—of thermodynamics, of electromagnetic fields—had been known to humanity since their discovery in the nineteenth century. Back then the laws had emerged among people seeking to heat and light their shadowy homes. They wanted efficiency. From such practical measures had come fundamental truths. An old term came to her: electrobiology. In the early twencen earnest physicians and greedy quacks had sold appliances that meted out small electric shocks, reputed to cure everything that ailed the human body. It hadn't worked back then, but something way out here was blending electrodynamics and chemistry in the hard cold of Pluto. For some reason the forces out there had conducted an experiment on this little dab of rock and ice, blending the two sources of animation—chemistry, electricity. Frankenstein's legacy? What's more, the experiment was still young. It looked like a work unfinished, left by giants for a better day, vast and massive but incomplete. When would the giants return? The sun took more than six Earth days to circle around Pluto's frozen globe, bestowing and withdrawing its heat. But something more powerful now drove this warming world. Something invisible. What had made all this happen now? The prospect of Earth's incursion into this bitterly cold place? Perhaps the entire experiment was itself a strange form of communication... And the Old One ... How had it learned so much? Superior intelligence? But what had selected for such wit and insight out here? Where was the evolutionary pressure? Or could the pressure come from some hugely larger volume? No ... too much. She had a gut suspicion that centuries ago, when Old One was young, something began a process of subtle tutoring. And before that, a process of deep, cerebral working among that zand's fore-parents. Otherwise how could one zand, unaided, have forged so far in explaining their bitter realm? That implied some agency had begun Old One's education long before humanity even knew the outermost planets existed. And to what end? Shanna looked outward at the unyielding black and wondered what huge surprises waited there. And how long they would be in coming. The new big nuke was behind them, coming up fast. If Proserpina burned her remaining reserves, she could forge outward into those bleak vast spaces. Keep pace with the bigger nuke approaching from below, surging up along the long sloping gravitational potential... out, ever outward into this space where bodies cold and mysterious circled in slow orbits, very nearly free of the distant sun's governance. And with some tricky maneuvering, Proserpina could find an iceball— maybe Charon—and melt some of that vast icy store for water, for their smaller nuke rocket. They all could still be a part of this immense voyage. She peered at the slate-dark world turning below in the vast hard cold. Thinking. But not if I'm replaced as captain. She sat bolt upright, fatigue swept away. Dad! The Great A! She flipped on the recorder and started talking. And down among the howling winds, in the gathering gloom of methane snowdrifts now mounding about them, the zand slept on. PART III BEYOND PLUTO The real voyage of discovery consists not in seeking new land' scapes, but in having new eyes. —Marcel Proust 1 LONG WAVELENGTHS On the largest scale, Julia reflected, the solar system was a spheroid cloud of debris. She looked at the big flatscreen display of an iceteroid they were passing, gleaming dully in the dim radiance of the ever-more-distant sun. The whole vast volume behind their ship, the High Flyer, was filigreed with bands and shells of flying shrapnel. Beyond Neptune, big ice fragments coasted in the Kuiper belt. At any moment a pair could smash together, or just clip each other, getting thrown into long ellipses, deep wobbly orbits. And this negligible-looking little blob of primordial gray ice and dust right here could, like the rest of the solar system's slow leftovers, now and then make a sharp hook by skimming near another piece of scrap and in a few years slam into a blundering planet. Earth's dinosaur-killer could have come from right around here. Julia shivered, not from the cold outside. Her pod was toasty-warm, comfy. But the strangeness that lay before them was approaching, and she had no idea of even what it might be. The voyage from Mars had taken months—a miracle, at speeds made possible by their fusion drive—and there had been plenty of time to study, learn ... and worry. Proserpina, the ISA expedition, was low on supplies and would have to depart soon from Pluto, under their mission plan. But High Flyer was bringing enough to sustain them both near Pluto for months more. High Flyer was to assist Proserpina, particularly with alien translation problems. In transit they had spent much time on the long-wave emissions from beyond Pluto. High Flyer would also venture out there, getting data on the bow shock. Those both at ISA and the Consortium were apprehensive about the seat-of-the-pants style of all this, but Julia and Viktor shrugged them off. They had been living that way on Mars for decades, making do. Viktor still worked on the Marsmat problem in his spare time, and when this adventure was done, they would go back to it. But now they were focused forward. "Anything new from Proserpina?" Viktor hollered from the control room. He could have spoken over comm, but he just leaned back in his chair and called down the gangway. They spent enough time logged into electronics systems as it was. And a husband and wife like to keep in touch in the most basic ways, too. "Not a peep. They're not due to report for nearly an hour." Nervously she checked the all-sky scan, anyway. Yes—far back there, she could see through their nuclear rocket plume's virulent blue-white. Pluto glimmering, and Proserpina's signifier overlaid. Two motes swimming in the black. High Flyer had completed its delta-V with both Pluto and Charon, looping a figure eight through, to lose velocity. They swung by and turned outward, following the streams of current that Proserpina had mapped. Straight out into the vast dark... "Getting a lot of that odd noise again," Victor called. "Coming up in the ultralow frequencies." "The stuff Proserpina picked up?" "Da—stronger as we go out." "I thought you said it was just more turbulence from way out at the bow shock." "Earthside advises me not. Say is too low, very low frequency, for these high power levels." "Then it goes in the mystery bin." "I already sent to the Wiseguy compiler. Maybe someday it will tell us something, huh?" He leaned back in his flex-seat and grinned, so that she could see him down the gangway. "Before we retire, maybe even." This was a standing joke between them. They would never retire unless the world ran out of mysteries, and out here that was quite unlikely. She grinned back. "Wrong. I have a big file processing right now. Remember, I sent your questions on? SETI Institute ran their Wiseguy, cross-compared with our data, and finally coughed up." "I don't believe!" "Come look." About time to peek at the processing, anyway. Her curiosity was as hungry as his. They had reviewed Wiseguy's capabilities, read through its mediated talks with the zand, the crawlies of Pluto. A spectacular discovery, the zand, Julia had to admit. A sentient species! Even more exciting, to talk with them. Her and Viktor's long years of slow, difficult work on Mars had not produced anything like the same result. The Marsmat was still an enigma; many still doubted if it was self-aware. Not that they had been just studying old data on the way out. High Flyer was outfitted with big phased-array antennas, to study the bow shock region. Their most intriguing work had been those electromagnetic maps Viktor had been developing. And now he and Earthside were using Viktor's work to discern whether there were coded messages coming in from the bow shock region. Shanna's crew had picked up some hints; it was High Flyer's job to sift through the sea of data, try to crack the meaning. "Program is smart," Viktor said. "Thinks can find words, connections." Julia blinked. She could not follow the spray of data on Viktor's working screen. But then she looked closer and thought about how they had labored over similar problems, struggling to fathom the Marsmat. The software—Wiseguy the semi-AI, plus elaborate metalinguistic codes—had been cobbled together Earthside. It followed on detailed theories of how language builds up from basic mental architecture. For decades the linguists had used the primates as a model, but in the last few decades they had extended it to dolphins and whales. It turned out that whale song was elaborate, beautiful—and simple. The first whale song deciphered had the structural complexity of grand opera, but the message (like most opera plots, and that was no coincidence) was, I'm homy, I'm homy, I'm homy. Later code work unfolded the intricate whale ways of broadcasting I'm over this way! and Food here. And, of course, Danger! There were other tribal messages, too, but none that could not be expressed in a sentence. Nature did not always produce sophisticated dialogue. But why should that Earthly experience apply to the extreme low-frequency emissions from out here? The old Voyager probes had first noted the noisy spectrum, but nobody thought it was more than plasma waves, the local weather. Proserpina had captured more for detailed analysis. Thousands of Earthside analysts had sweated over those, and High Flyer's better data. Viktor had been handling the elaborate merging of all this, and now... Now there was a new angle to the process. Viktor pointed it out, and she saw it suddenly, after minutes of scrutiny. Structure leaped out of the flow. The incoming digital streams broke into constellations that resembled words in their numerical architecture. "And they are! So the Earthside tech types say." Julia finished her explanation to a blinking Viktor. "Our words. English!" "Is impossible." She grinned and put on her mock-gruff Russian accent. "Is not." "Must be error." "Unless whoever's sending this has heard us first, and they're replying." "At ten kilohertz? No one uses frequencies that low. Waveforms are huge!" "Oh?" "Da! Even early radio, Marconi, he used only hundreds of kilo-hertz—pretty big waveforms already." He stopped, eyes widening with a sudden idea. "Must calculate wavelengths." He scribbled on his slate, frowned, and scratched his short, salt-and-pepper beard. "Ummmm ... Marconi could use those frequencies because he was using really big antennas. Right." "Right how?" "Da—made of chicken wire, they were, strung between houses, like early Russian pioneers in radio— She chuckled. "Who discovered it all first, along with the telephone and laughing gas—yeah, I've heard. Point is, my earnest darling?" "That Marconi's antennas had to be at least a fraction of the size of the wavelengths he used. Or else they couldn't radiate very much—or receive much, either." "That was the best he could do?" "Da—and this is the best they can do." "Who?" Julia was thinking about antennas, which she had worked with for decades but had taken for granted. "The whoever that sent these signals at frequencies of ten kilohertz. Maybe they picked up our transmissions—God help us! Maybe all our radio and TV for the last century. But can't reply at those frequencies. Because, see, at normal radio wavelengths, we're talking antennas maybe a meter in size. Way too small for them. Instead, they go for ten kilohertz—because that's a wavelength they can manage." She blinked. "Not a joke, right?" "Nope. Divide the speed of light by the frequency to get the wavelength and therefore the antenna size. Old stereo systems had three speakers: the smallest, the tweeter, for high-pitched sounds; the big woofer was for bass notes—down to low-frequency rumbles." Most of this was new to her, but she got the principle. "The thing that sent us these messages—the ones the Wiseguy codes are grinding away at right now—is—" He grinned. "Really big woofer—at least thirty kilometers across. Aliens are giants." 2 THE TOWERING ICE SHANNA SETTLED DOWN INTO her smart couch and went through the setup protocols. Showtime! Every time she went on watch, Shanna knew she was born to do this. From the beginning of this long mission she had found her hours on watch the most exciting she had ever known. Even after years on the mission, whose goals had veered radically as they learned more, her pulse raced when she went on duty. Being captain helped. Telepresence duty was the absolute best. Boldly exploring, while sipping aromatic Colombian. In the 3-D environment she saw the Pluto landscape in sharp detail merely by turning her head. No sensation of movement, or of cold, but sounds came aplenty: the slow sigh of breezes, the crawler's clanking, the crunch of ice, a crisp fizz of vapor boiling off, which was a lot like bacon frying. It had been weeks since she had actually been on the surface, and that was the crash. So this was the next best thing: phony Pluto. Digital discovery. Earthside was superworried about safety after that crash—the Chicken Little culture was quite frustrating. Politicians actually said, about every activity, even exploration, that safety was always the number one consideration. Imagine human history if we had always felt that way, she thought. If it kept on like this at ISA, nobody on Proserpina might ever get to go back down to the surface. Come billions of kilometers and stop a few hundred klicks short... crazy. She peered at the landscape steadily, letting detail sharpen. Stark shadows cut across the dirty gray plain, and the sun was a glaring point. Under Charon's gloomy crescent the thin methane atmosphere scattered little light. Darkly twisted, tortured sculptures jutted from the ice sheet. The slow-motion weather here had worked on them for eons on the somber, sleeping plain. The moon loomed huge and ominous above a sharp horizon. It held a certain austere beauty, but the mere landscape told nothing of its incredible cold. They had been drawn here by the unexplained growing warmth of this place—yet "warmth" was the wrong word. That grim, dismal view was only 120 degrees above absolute zero. Compared with Pluto's temperature measured Earthside back in the twencen, a brisk 42 absolute, this was Florida. A moment's exposure would not merely freeze her; it would snap her bones into confetti from thermal stresses. Yet here life stirred. Incredibly. She had been down there twice, and it was still hard to believe. Life on Pluto. Amazing enough by itself. Not just the simple legged forms that crawled and walked these bitter, barren hills—recent discoveries, thanks to telepresence, letting her drive the crawler from orbit. Or the flyers, angular or bulbous. No—there were others who descended from the sky, those from even farther out, beyond Pluto: the Darksider machines. Nobody, not even the most extreme exobiologists, could have guessed. Shanna resisted a morbid feeling: that the fragments of crumpled metal she and Jordin had picked up, mingled with those ice chunks, were actually scraps of... well, flesh. By now she knew better. Not flesh, but once living—if machines could truly live, even very smart machines like the Darksiders. But emotion yields slowly to reason; she still thought of the Darksiders as autonomous intelligences. Even after their captive onboard turned out to be a robot of sorts, able to carry out instructions well but incapable of original action. She inched her crawler forward. Working in a comfy work pod, directing the crawler with telepresence gloves, she had to be careful not to alarm her prey. Ahead, the gunmetal-blue, oblong Darksider didn't seem to notice. Maybe it was recovering from its landing. Or playing possum. Remember, you're the new kid out here. Maybe we don't know all that lurks in these shadows. You might look like an intriguing new kind of lunch. She moved her hands in their command gloves and made the crawler grind forward another meter, crunching ice. Her low crawler was creeping on treads up to the Darksider at a shadowy angle. In the incredible cold here slow was always a good idea. Parts froze up without notice. Circuitry went dead, and even an emergency warm-up couldn't revive it. When the crawler stopped or pivoted, she sent a surge of electricity through it just to keep it warm. Moving here had an ominous, ponderous feel that got on her nerves. Another sluggish move, then a wait. The Darksider didn't seem to mind. Scavenging for Darksider remains had turned out to be easier than skystone hunting. Earthside wanted more parts, to better understand the different Darksider designs. Skystones, a rather poetic name for the rain of incoming meteors. She had come to like the whispery acoustic language of the zand, and their name fit, a combination of "zany" and "grand." They were both, speaking in long, wispy chords that skated great distances through the thin nitrogen-methane air. Chilled words, pealing out with a rolling rhythm that reminded her of whale song. But unlike the whales, this time she caught what the zand were saying. This was yet another wonder, but one human-made. Wiseguy had picked "skystones" as more expressive than English's "meteors." And indeed, the incoming rocks did not flare in the chilly "air" here, just slammed into the ice, carrying fresh Darksiders—from where? Their captive Darksider would not say; perhaps its narrow intelligence did not know. "Got the target?" Jordin asked over comm. "Dead on. Big one, looks like parabolic antennas sticking out of the carapace." "Let me know, huh?" His tone was edgy. "I'm on this watch, too, y'know? It's not nice to just say nothing, leave me hanging here." "I'll try being nicer if you'll try being smarter." "Hey, just because I screwed up capturing that pair of Darksiders—" "Okay, okay." She should be keeping peace, but he was sometimes irksome. And he had messed up the last telepresence run. "I'm just watching it for now." "Oh. I'll get on the spectral scan." "Actually I thought you were napping." In his lately familiar miffed tone he shot back, "I'm checking your every step." "Don't need a babysitter, y'know," she said. "Catch up on your sleep." "That an order, Captain?" Jordin said stiffly, with a subtone of derision to boot. Yep, I'm still captain, and that's what's bugging him. "Sure. Nod off all you want. Earthside won't know." "Might just do that." Actually he was right. They had all been working so hard, for so long, that four days ago Earthside told her to institute mandatory days off. Nobody was going to honor that, she could tell right now. They all loved this vast, strange problem set before them. The shadowy mysteries kept them going. Jordin signed off, though it would be just like him to keep his headphones on as he slept, just in case. She couldn't seem to strike the right notes with him these days. She knew she was getting a bit snappish, but no wonder. The approach of High Flyer was stirring anxieties old and new. And this long mission was rubbing personalities against each other. Plus some unusual stresses... Dear old Dad had come through for her, right—but as Axelrod the Great, wielding his legendary deal-making magic. They'd had a lot of conversations the last few days—one-way at a time, of course, given the huge distances. "I'm gonna have to burn a lot of chits to keep you as captain," Axelrod's concerned face had said. "It's going to take promises, and I'll have to make good on them. Remember what we talked about before—plenty of people want Darksider tech. They're betting it'll blow away any robots we've got here." Meaning, of course, that the Consortium was betting. Even though this was an ISA mission. "Well," she'd replied, "as captain I'm your best bet to get anything at all from this mission." His answer hours later had infuriated her. "Y'know, honey, High Flyer can get us Darksiders, if necessary." Lucky for tape delay; her first reaction would've been a disaster. Something on the lines of "The Mars Couple? Over the hill, Dad." Finally she'd settled for "It might be tricky for the Consortium to get around ISA's claims of first discovery. Ask your battalions of lawyers. But if I back up your claim, as the Consortium's rep on this mission all along, it'll be a lot easier. Daddy dear." His face showed grudging admiration on the next vid. "Good point; so we have a deal. Oh, and I'm getting interest in having some small zand back here, if the exobiologists can figure out how to manage it. We want them alive, not stuffed. Possible? Nobody knows. I'll have more details later." What a Victorian he'd have made! Zand aren't European, white, or Christian, ergo they have no rights. Without seeming to disagree, she'd sent, fingers crossed behind her back, "As they're sentient, they'll have to agree to go, Daddy dear." Might as well keep the edge in the dialogue. She was still waiting for his reply. A ping from the instrument board snapped her back to the present. Hey, concentrate. One more meter ... Out of shadow now. Closer... Her boards reported weak microwave emissions from the prey, but it remained stark and silent on the snow. But no, not a corpse, she reminded herself. The latest arrival, radar tracked from far beyond Pluto. Better to grab than pieces. Her hands moved in air like a pianist's. Move. Close with it. The crawler probe clanked forward and stuck out spindly grapples. Grasped. Gotcha. She reeled in her catch like a fish—back to the waiting lift vehicle, in slow, deliberate moves. While the probe and its burden were still lifting off for the mother ship, Proserpina, the DIS computer ship-mind whirred through a preliminary analysis. Shanna watched the silvery ship rising toward them over the curve of the planet and felt sharp anticipation. The probe made it back without incident. The crew did maintenance, getting ready to leave orbit. Shanna waited for her chance to see the new catch up close. The new Darksider was nasty, which to a biologist meant interesting. Those fierce-looking claws—tantalum carbide, hard and tough even in supercold. The structural shell—aluminum/titanium alloy. (Magnification, please.) Those looked like mechanical relays of some sort, and they were made of solid mercury? Sure; at these temperatures, why not? But what was the purpose of those patterns of rare earths? And those curves, seen in projection, looked almost like a conventionalized helix—Oh. Shanna spoke into her recorder. "Hypothesis: these devices, whatever they are, contain a genetic model. Yeah! A helix, too, recalling DNA. A model of what? Of the 'ideal' zand, from a Darksider's point of view?" Her mind made a large leap. "We already know that these infalls came periodically, from dating the ones we found, centuries old. Chow-Lin did it using isotopes, I dunno how. So—when Pluto arcs out along its steeply elliptical orbit, something hammers it with Darksiders. Been doing it for at least three planetary orbits—that's nearly a thousand years! Darksiders scan the zands. Those that don't measure up they squish." Guided evolution? Part of the grand experiment on Pluto? The probe clunked into its housing; she heard it ring. A conveyor rattled, taking its burden down to Proserpina's low-temperature laboratory. Time to get to work. Appropriate background? Something romantic but reflective, she decided; Schumann's Konzerstück. Supported by mellow French horns, the piano chords rolled out while DIS, now in direct physical contact with the specimen, shifted into high speed. She fancied she could hear it hum. Views of their catch filled the curved screens around her. Well, well—this beast hadn't been bent from sheet metal in a machine shop, that was sure. Coldformed, one molecular layer at a time, grown as crystals were. From the Oort clouders' massive perspective, she guessed, a delicate job of microengineering. And the chilling thought came: from that same perspective, the injection of those "tools" into the zand culture would be no more a "raid" than the injection of antibiotics into a human bloodstream. The thing was not dead, instruments said. Maybe shut down by itself, to save power. Or maybe orders from some mysterious Other. With care, and with the help of DIS, she could probably feed a trickle of tailored DC into its superconducting circuitry and bring it back to life. Make it move, clash those jagged claws, jump up and down. (Boogie! she almost heard Grandma say. Her father, alas, never got that loose.) Possibly attract its makers' attention that way? If one of her own hemoglobin molecules tried to get her attention, would she notice? That was the relative scale between herself and the hypothetical somber dwellers in the Oort cloud, in the far dark beyond the warm worlds. Yet they had made the rickety zand biosphere, whoever or whatever they were. They had plenty of room, too. Where the sun's gravitational grip slackened, countless icy islands swung, taking centuries to complete a single orbit around the dim home star. That archipelago stretched halfway to the next gleaming stars. As infinities went, it would do quite nicely. They had come seeking the root of a mystery, never anticipating that the answer would be so vast and startling. At the end of the twencen, Pluto's atmosphere had seemed to start cooling off, as the planet arced outward on its slanting ellipse. Atmospheric specialists predicted it would freeze out somewhere before 2020. Only it hadn't. Instead, even as the first probe sped outward, the thin film of chilly nitrogen and methane cloaking Pluto began to warm. Other compounds began spiking their spectral signatures up on the most sensitive Earthbound detectors: water vapor, carbon dioxide, even nitrogen wedded to oxygens. And as the mission had prepared, a further, ominous puzzle arose: the solar system's bow shock was moving. This "pause point" is the working front where the sun's outward wind of particles meets the interstellar plasma. This forms a surface much like the curve made by a ship powering across a lake, seen from above. Before, the nearest this bow shock had gotten to the sun was about one hundred astronomical units, a full hundred times farther than the Earth-sun distance. But now that fluttery front lay only a few AU beyond Pluto, now just a tad beyond 40 AU from the sun. If the solar wind let that wall of molecular hydrogen behind the shock intrude into the inner solar system, Earth could be destroyed. Even approaching partway in, say into Saturn, would be very dangerous. That seemed unlikely to the specialists, but without an explanation of what was happening beyond Pluto, few found that comforting. At first Shanna had thought the bow shock issue was pretty nebulous—after all, it was about thin gases, right?—and had to keep reminding herself of an old diagram from the early space program. It showed the solar system plowing through the interstellar spaces, pushing gas and plasma before it like a snowplow. If a voyage from the sun to the nearest star were like a marathon, in reaching Pluto the runner would have gone only fifteen feet. Both Voyagers and Pioneer had passed into the outer realm, genuine interstellar space. But if the solar snowplow weakened—or the pressure of the interstellar gas increased—the boundary would intrude farther in, brushing the planets. One swipe with molecular hydrogen and Earth's oxygen would combine, making water and a lot of energy. The biosphere would get hot and breathless within days. Even little trickles of hydrogen could hurt a lot. She often gazed at the old NASA sketch—from back before it joined ISA—of the region they were now exploring. All very clean and scientific. No mention of lethal weather. "IMAGE003 GOES HERE" And now Pluto held life. Not just chilly slime molds and small crawly creatures, but a few species in all, crowned by the self-aware zand. And her bet was that these in turn were being altered by the sky-stones that fed them ... and the Darksiders that bled them. Earthside scientists now bet that Pluto was driven by energies somehow imported from where the bow shock roiled and frothed in plasma arcs bigger than planets. DIS said, "Transmission due." "Ummm." She owed it to Earthside, after the grief she'd given them, to at least keep punctually to their radio schedules. A fundamental rule of missions: there was always some damn thing interrupting. She told DIS to start trying revival methods on the newly captured machine. It had gone silent shortly after they began talking to it. Chow-Lin and Jordin had spent weeks trying to get the first Darksider—their hitchhiker—to respond, and concluded that it had been ordered (by what?) to shut down. Now she wondered if anything would work on the new one. She switched on audio and visual and tried to relax in her obliging smart chair. Deep breath— "This is Astronaut Shanna Axelrod, aboard Proserpina, in Pluto orbit." It still gave her a charge to be able to say that. (And Grandma would have warned her not to get so swellheaded.) They would edit and polish for the whole brimming Earthside audience, of course, as now required by full-disclosure laws. She hoped no laser-link pirates had caught her latest reports. They had started to swoop into the beam and carried off choice nuggets, decrypting them and bootlegging them in time to compete with the cleaned version. Embarrassments galore, unless she kept close to the vest. But who could, all the time? In the background Schumann sang, and DIS clucked and ruminated, while she talked. Arpeggios rose from sonorous lower octaves. The longer this mission went on, the more she needed music's sense of human connection, of grand prospects. For that, the romantics were better than even Bach, for her. "Not much progress on the Darksiders. The ones in the cold lab talk for a bit, then shut down. DIS is working on it, but my guess is they're unable to run very long without instructions—from where, though?" She felt a fluttery twinge of unease. Minimal speculation, ISA had ordered. Earthside thought she was moving too fast. She wanted to know—and it was their lives on the line out here, right? Easy, now— keep your tones proper and level. Or should she record these little reports and have DIS take out the stress-diagnostic frequencies? Yep, she should consider that. Tomorrow. "So, zilch. The local Pluto life-forms, the zand especially, I'd love to take the time to study them. But they're maybe a sideshow, Jordin and I—and the rest of the crew—think. You're just going to have to rely on our judgment." She took a deep breath. Even after years of talking into silence, knowing that her message would take hours to get to its listeners made her uneasy. Humans need conversation, not oration. Then there was the psychers' explanation. Reminding her of how far away they were from help? With one exception, yes. "And, speaking of the zand, I've had some second thoughts on what to do about their situation. They're on the wrong end of a predator-prey dynamic. We can help them, sure, though that goes way beyond our mission profile. And we're using the Darksider-type strategy! Hiding from sight and occasionally sneaking a meteorite in amongst them might be as bad for them as to have Lady Bountiful descend from the clouds in full view. It could make them completely passive." Amateur psychoanalysis, sure, but it made sense even for aliens. Skystones will fall when needed, right? Lightgiver will provide; they need do nothing. "There's quite enough external control over their fate as it is, with even their genes—if I can use that word imprecisely—messed with by outsiders. I'd like to see the zand stand up on their own feet, even though feet are something they haven't got." Hopeless anthropomorphism: she could all but hear Dr. Jensen snap out the words. Hey, it's a metaphor, guys. Avoid argument, Shanna told herself; you're really in charge out here, calling all the shots. Captain! But get some advice first. "So"—pause for the beat—"I'm having DIS plot us a new course, toward High Flyer. I want to link up with them. I know, I know—Proserpina wasn't made to go out into the comet-rich inner disk. But we've picked up a lot of easy water here, heating the ice. We had the lander haul some up on the return from recon descents, using our 'bots to do the grunt work. We're fully fueled. The mysteries of Pluto can't be solved on the planet alone, and we'll make a powerful team out there, with High Flyer." There, it's said. Not crazy, no. Hell, Earthside sends a totally new kind of ship out to explore further and wants us to meekly head on home? As the original mission plan called for? The rest of her crew agreed, of course, but not strongly, and it was my decision, damn it! Mine alone. Captain. Proserpina's pokey fission nuke drive could only make it far enough to nip at the fusion-burn heels of High Flyer. She made herself take a long breath. We can stay in the game. "I want you to consider this as an add-on to our mission. Also backup for High Flyer. We—" Clanging. Loud, rasping alarms. Shanna leaped from the immersion pod, heading for the pilot's chair. "All hands up!" she sent on comm. A whole row of instrument lights winked red. The hull was overheating. But how? Panic flailed her. Heating from atmospheric friction? Maybe—were they falling out of orbit into atmosphere? But, no—the holoscreen image of the planet and its satellite showed Proserpina precisely on its looping curve, where it should be. What could be heating the hull and blasting salvos of static into her music deck? Reflexively she shut it off. Radio and microwave readouts jumped to the top of their scales. The external cams flared with light. Sheets of rippling electricity, swathing Proserpina's hull and rebroadcasting like crazy. "What!" Could any get in here? Flashes of light current? And how much microwave dosage was she getting? Best get into her insul-suit—and fast. "Crew! Go to insul-suits." She shucked her coverall and squirmed into antiradiation garb that looked like a silvery wetsuit. It clung coldly to her bare skin. Jordin came through a hatch, doing the same. Banging. Thumps. Screeching metal on metal. From inside. "Oh damn! The Darksiders—" Shanna raced hand over hand, down a tube, around a corner. She could hear crew footsteps thumping in the corridors above. She slipped, hit the wall, rebounded from a bulkhead, swiveled—and stopped before the view port for the cold lab. Cracks snaked across the frosty circle. The alien body inside had revived. Its tin-gray parts moved with jerky purpose. It jumped and jittered. A claw swung at the view port again and stopped. Shanna flinched away. It—or the intelligence controlling it—must have realized what would happen if it broke out. Emerging into ship temperature, the rules of superconduction would be suspended. Ordinary electrical resistance would prevail. Heat would build up as its currents suddenly met resistance. Zap. Death by Ohm's law. She watched the thing jitter around uncertainly. The Darksider body must have reacted reflexively to the input surge DIS had tried. It came to life and automatically fought to escape. And then thought better of it... Now it stood motionless on the cold lab's examination table amid the restraining straps' tangled ruin. Shanna fancied that it glared. "What's up, DIS?" she asked. "I am trying to integrate its behavior patterns with input." The voice was coded to be male and warm, tailored to her tastes, but it still managed to come over as canned. "Any ideas?" Jordin asked. "It has some limited autonomy. I gather from inductively reading its inner currents that it is caught in a behavioral dead end." "Something like a logical loop?" "Perhaps." Without being asked to, DIS had switched from lab analysis to dealing with the immediate emergency. Good ol' DIS. The heating of the hull, its sensor monitors informed Shanna, affected the surface skin only. Those secondary, lightning-bright lower-frequency discharges were annoying—obviously she wasn't going to finish her message to Earthside just yet—but nothing more than that. "Jordin, keep an eye on it," Shanna said. "I'll brief the crew and check the hull." She relied on her training, got that done, then got herself calmed down. Getting her immediate adrenaline-pumping alarm to fade, her racing heart and gulping breath settled back to normal—with meditation skills, that took two minutes. Then came a wave of fierce joy. She couldn't reach out to the presumptive aloof denizens of the Oort cloud. But quite evidently something had come exploring on its own and touched them instead. Rippling currents along their hull, prodding its emissary Darksider 'bot. What could do that? Time to gather the crew and do some brain-storming. The burden of being captain was the detail, but the reward was seeing the problems, having first crack at them. Maybe have a little party afterward to celebrate leaving Pluto orbit. They were all getting irritable, even the once amiable Jordin. So she gave herself one more minute and listened to good ol' bombastic Wagner. 3 INSTIGATOR Though the galaxy appears to be a swirling pinwheel of light, most of it is nothing. Emptiness. Utter black oblivion. Or so it seems to small mortal eyes. Yet huge resources abound in the dark. Entities move there, unseen. They witness the ebb and sway of worlds from far beyond. Their perspective is larger, longer. This is how they see the inner, warmer realm: The forms of life that arise on planets, encased in flesh or carapace, in fur or fin, see the universe through a narrow slit of the spectrum, light's brimming wealth. Evolution prunes and whittles its subjects so they take advantage of the greatest flux their parent stars can offer. Seldom does planetary life evolve to sample the lazy, meter-long wavelengths of the radio or the pungent snap of X-rays. So they do not witness the chaotic tumble of great plasma clouds between the stars. They see nothing hanging between the hard points of incandescent light, and so they falsely assume that what they call space is just that. Yet stars, those brimming balls of radiance, continually spew forth matter which fills the void. The starwind streams out, expelled by snarling magnetic storms. A human hand dipped into this gale from a spacecraft would snatch up only a few tens of molecules. By the time the thinning gale reaches the rim of the solar system, the density drops to a thousandth of that handful. Then this billowing wraith wind thins further—and meets the colder, denser fog that hangs between the stars. There, between sun space and interstellar space, the comets coast, waiting for a chance collision to begin their weary inward journeys. Something happens in that realm that is no mere meaningless dance of matter and energy. Though invisible to human eyes, the banks of clotted plasma moving there are complex and forbidding. And alive. Seen in an immense radio lens, the vast reaches would seem to have knots and puckerings, swirls and crevasses. Here the particles thicken, there they disperse into gossamer nothingness. And moving amid this shifting structure are thicker clots still. Some huge eye, sensing radio waves a kilometer long, would see them as incandescently rich. Their skins would shine where magnetic constrictions pinch and comb their intricate internal streamings. Filaments like glistening hair would wave and shimmer in the slow sway of ancient, energetic ions. An even larger "eye" could hear the booming calls and muted, tinkling cadences of their conversations. Their talk began before the birth of the arrogant star nearby, now blaring away its substance in winds and magnetic whorls. These Beings are unseeable by anything that evolved on simple, raw planets. They live through the adroit weaving of electrical currents. They feed on the electric potentials that trickle through the comet clouds. Their interiors are highly ionized plasmas, filigrees of ions and electrons in their eternal deft dance, long strands smoldering and hissing with soft energies. Moving at tens of kilometers per second, these inner cores sweep up magnetic fields and harness the induced electrical fields. Even the best astronomy of small, planet-bound, chemically driven intelligences could only glimpse the momentary flaring of these plasma veins. The larger arteries and organs of the Beings would be beyond all but truly immense radio eyes—certainly far larger than anything contemplated by humans, even after the rocket-powered breakout into their own solar system. Each of the Beings stretches across a light-day of thick plasma and molecules. If the entire solar system, including dim Pluto, were reduced to the size of a human fingertip, the bulk of the Oort cloud of iceballs would lie ten yards away from that finger. Yet these spaces could still encompass only a few hundred of the Beings, and have for billions of years. Bodies so vast must run by delegation. A pulsing stomach busy digesting induced currents cannot know immediately that a distant molecular arm hungers for this spark of life. The intelligences that evolved to govern this huge bulk then resemble parliaments rather than dictatorships. Yet even assemblies have names. And must at times speak with one voice. The habit of these particular Beings had long been to assign names by the principal traits each displayed—age-old but not immutable. Still, to other intelligences these traits themselves were mysterious, fundamentally unfathomable. To represent them by the signs and conventions of mortal discourse is to falsify. Further, over the yawning eons, Beings formed linked pairs, an electromagnetic yin and yang. This proved to have greater stability, since countercurrents repulsed, keeping nearby Beings from merging destructively. Most moved and grazed on upwelling fresh fields, in company with a Being of opposite polarity. Assigning the linkmates gender, as she or he, is a human convention only. Outlining the unknown begins with a gesture toward the known. To convey even a sliver of the flavor, though, demands simplification. One must remember that the gift and curse of language is to render complexity into clarity, through a simplicity that must lose much. This can make profundity appear commonplace. Yet it must be. What follows should best be understood as singing. Forceful broke a long, tense silence. Serene echoed. This was no surprise. She had opposed the Inbound investigation from the start. From Ring, Forceful's grim linkmate, came ringing agreement. A quick chorus of assent forked forth from Mirk and Chill, their social offspring, now grown beyond the early stage of Protos. Beings shaped natural, recently born Protos into members of their community. The young ones liked the far, cold reaches of the Vastness beyond all stars; it kept them agreeably out of reach. Soon, despite the time delay that waves took to span these reaches, came assents from them and their linkmates, Sunless and Dusk. These were echoing calls, hollow-sounding and rich in bass ion harmonics. Recorder mused. They formed a block of six: Forceful and Ring, their Protos Mirk and Chill, and their Protos' linkmates Dusk and Sunless. Thus far they had been able to outweigh with firm argument the others, the Eight, who still wanted to press on. That faction desired to plunge in past the outermost planet's eccentric orbit and into the hot lower depths. Only once before had any Being ventured into those treacherous regions. The ancient, woeful tale of Incursor had taught the Beings not to venture inward. That Incursor had been brave was never doubted. In the Beings' early era, when they first evolved to consciousness in the bow shock, much had been ventured. Incursor's aim had been to fathom fully their own origins. He had voyaged inward, in an expedition assisted by many Beings, a faction known still as the Inbounds. Incursor discovered much, but in studying an inner world he became lost. Legends spoke of occasional bursts of Incursor's unique voice, but the messages were tangled in the starwind and never lasted long. Sobered by this, the Beings took as an article of faith the Outbound view—that exploration of the stars was their destiny. But the Inbounds never quite gave up. Instigator had slowly marshaled her strength. For long eras she had worked to understand how life of any kind could arise inward, and her experiments were renowned. Instigator's findings were already revered by Beings around distant stars. And now the balance had been thrown even further the way of the Inbound Eight, by disaster. Rumors had whispered in from distant Beings—remote even by their own vast standards for measuring space—who fed near the older stars. Strange tales indeed. Stories of the surfaces of many little rocky worlds tucked in close to stars, which had lately been rotting into life. Here "lately" meant on the proper scale of high intelligences—the time needed by a star to trace out its orbit around the center of the galaxy itself. A respectable time. The words from the stars spoke of a low, obscene, hot life. Solids. Not powered by the clean transformations of electromotive force, but by the clumsy building up and tearing down of molecules. These rot-born beasts were swamps. They seethed with the messy contaminants that made up the cometary iceballs. Their spectral signals the Beings had deduced from their explorations of the icy motes that would, on occasion, loop in and out of planetary systems, swinging into lethal zones where heat clawed at them. Instigator had told her fellow workers. That was some time before, when she had first reported on the genetic experiment she had started on this local system's outermost world, nearly a galactic cycle ago. Forceful shot back, Instigator sent fluttering coils of turbulence at this insult. Forceful dismissed. Instigator shouted. Sunless and Dusk sent in their gibing, hollow tones. Even in this argument they and Mirk and Chill followed the ancient convention, that subordinate generations spoke as one. If they disagreed among themselves, they remained silent—which was often a blessing, their elders strongly believed. Instigator sent. Forceful rejected this in plumes of incandescent effrontery. Ominously Instigator coiled portions of herself into dark striations. Recorder noted. The pause before the last symbol-term was significant, placing Recorder midway between the factions. Instigator shot back. Forceful said. Instigator purled off portions of herself to show disarming openness. Forceful sent coils of skepticism. Recorder observed. A chorus of Ring, Forceful, Mirk and Chill, Sunless and Dusk—all sent the same doubtful interrogation. Recorder showed startled puzzlement. Forceful sent with quick, angry striations. Recorder sent rumbling bass notes of discordance. Forceful countered. Recorder sent firmly, Instigator sent. Dusk sent. Instigator said. Ring said with an indignant aura. Instigator sent mildly. Recorder paused to let their momentary angers dissipate along the intricate magnetic field lines. Derisive laughter came, but in such long wavelengths that the Being—or Beings—who sent it could not be resolved, even using the antennas of the largest of them, Recorder. Vexing, but Recorder had suffered such insouciance before. Recorder said. 4 THE SOLAR RAMPARTS Shanna GAZED at the pale crescent of Pluto falling behind. Its moon, Charon, looked outsize, fat. It was, at about half Pluto's diameter. Thirty years ago, the astronomers said, it was just an iceball. Now it brimmed with a filigree of warming nitrogen and water, as Pluto did. Pale gas rimmed both crescents. The source of the energy that drove this lay farther out from Pluto. And Uziki, the shy physics type, had found out how. After Ferrari's death, the remaining five had reshuffled duties to cover the tasks. Her original crew position was in engineering and computers, but she had a Ph.D. in plasmas. She had found that the energy came in subtly, as electrical currents in a thin plasma column, pointing straight in toward the sun. The nuclear drive rumbled hard at her back, rattling the decks. Proserpina was now riding along that column's outer sheath. The plasma physicists Earthside thought they could learn a lot about how the whole mechanism worked by looking at the conditions at its boundaries, for some reason. Not her field of expertise, but it made sense—something was confining the current flow, shaping it neatly toward Pluto. What lay at the other end of this mechanism nobody had even guessed, so far. Something big and strange, for sure. "Picking up a lot of turbulence," Jordin said from the side couch. "Plasma waves?" "Yeah, a lot like the stuff coming from the bow shock zone up ahead, I'd say." "Low frequency? Like Voyager picked up?" About plasma physics she knew at least enough to ask questions, but not much more. "Sure is. Pressure waves, running down this sheath, keeping the currents nicely aligned." "A kind of... plasma pipe?" "Yep. Energy flow pipe, with Pluto-Charon at the far end of the circuit." Jordin was intrigued, fingers working in his command gloves. He waved in the space before him, and pretty colored displays outlined the flow patterns. Currents arcing in, nose-diving, finally captured by the crusts of the two worlds. The heating effect flared visibly as a dull orange glow in the icy crusts. Filigrees ran under the blue ice sheets, melting the thinnest layers into gossamer vapors. Clouds fumed into the gathering atmospheres. "Damned odd," was all Shanna could think to say. "Not an accident, no way," Jordin whispered, eyes intent on the constant play of pattern. "What kind of thing can set up magnetic pipes bigger than planets?" Jordin shrugged. "I dunno. Earthside is still talking about all this as a whole new kind of biosphere, driven from outside by currents—" "I'll say!" "—but natural. The astrophysicists are playing games with the bow shock region, tying its moving into all this commotion on Pluto." She snorted. "That just moves the problem back a step. What made the bow shock boundary move in from 100 AU?" "You don't get the game." Jordin grinned. "Moving the cause into their ballpark means they get to make the pitches. Get the hurry-up funding. Make headlines." "So young and already so cynical." "You expect scientists to be loftily above it all?" She nodded grudgingly. "Okay, now you're starting to sound reasonable. Time to up my medication." It took six days for Proserpina to overtake High Flyer. Its exhaust burned diamond-hard against the black. Escape velocity from Pluto was 1.1 km/sec, only a tenth of what it took to escape Earth's grasp. Orbital speeds were low out here, too. Pluto moved at a paltry 500 m/sec, not a whole lot faster than a jet plane. Out there in the Oort cloud, speeds got even slower. Shanna had a momentary comic picture of herself running to catch up with a planet... And there it was, a bright dot rushing into the far dark. High Flyer was a huge thing, like a skyscraper with a big bright rocket flare stuck on one end. Most of it was gray bottles of water blocking the hind drive from the living quarters. In space geometry is the only guide to size, and even geometry needs a measuring stick. Here the only guide to her eyes was the air lock, the bulky structure a mere small cap near the top third of the craft. This was a big nuke. And the first fusion rocket of major scale, built for both speed and distance. No mere pod sitting atop a big fuel tank, which in turn fed into the reactor. Of course, the parts had to line up that way, no matter how ornate the subsections got, because the water in the tank shielded the crew up front from the reactor and the plasma plume in the magnetic nozzle. To even see the plume, High Flyer had a rearview mirror hung amid-ship, out ten meters to the side. The whole stack was in zero g, except the top thick disk, which the crew seldom left. Forty meters in diameter, looking like a dirty angel food cake, it spun lazily around to provide a full Earth g at the outside. There the walls were meter-thick and filled with water for radiation shielding. So were the bow walls, shaped into a Chinese hat with forward viewing sensors. From inside, nobody could eyeball the outside except through electronic feeds. The whole ship was well over a hundred meters long. Built like a barrel, it rode a blue-white flare that stretched back ten kilometers before fraying into steamy streamers. Plasma fumed and blared along the exhaust length, ions and electrons finding each other at last and reuniting into atoms, spitting out the actinic glare. The blue pencil pointed dead astern, so that at the right angle the whole scene was an exclamation point, with the sun as the dot. Proserpina hauled up within a kilometer, and the two ships fretted over the details of making the transfer. In the end Shanna won out. Proserpina was cramped and showing wear; and she wanted to see inside the bigger ship. She, Jordin, and two other crew would come across in the shuttle. Part of her wanted to play status games and make them come to her, but her own curiosity won out. She wanted to see what this monster of a ship looked like, and it would indeed be good to get out of the house for a while. Not that she looked forward to a tech-talk fest. Whenever ship crews got together, there was a lot of talking shop, but out here she could use some simple human contact. Being captain always kept you at a distance from your crew. And the hyperlink to Earth was no substitute for real talk, either. Last week she got a memo that said, "Cascade this to your people and see what the push-back is." It put her off reading her e-mail for days. They wedded to the air lock gingerly. The lock was big and bulky, like everything here, with fancy safety bells and whistles. Mass to spare, she thought sourly. They cycled through, in formation. For Earthside audiences High Flyer was recording every greeting, handshake, joke, and guffaw. They got through it, agreed to turn the cameras off, and Shanna had a moment to assess this Julia Barth, senior woman among astronauts, legendary for a crusty exterior that concealed a sharp intelligence. She stood straight, shoulders back, smaller than Shanna had expected; the great should be larger, to match the reputation. Julia was compact as all astronauts were, maybe a tad stringy. Her face was lined, mouth cocked at an assessing angle, eyes quick. Suntanned, too, from working in the Martian domes. Already, Shanna was sizing her up. Her husband, Viktor, was quiet and gruff, big and muscular among the slim astronauts, eyes flicking from one face to another as the conversation moved. Equally famous, just as at ease. They both seemed energetic but calm. Maybe the Mars Effect was real. Shanna wondered how they were in bed together... Everybody knew each other's profile, had read their books (some ghost-authored, some even eloquent), and they passed through the usual compliments. Shanna knew she would take an industrial-strength makeover to be presentable, but the High Flyer men all told her how great she looked. One, Hiroshi Okada, had gleaming eyes and a mirthful grin. She liked him at once, and not just because his compliments didn't seem forced. In cultural profile High Flyer's crew was like hers. By no accident, most spacers were from North America or Asia. Those were the cultures, mid-twenty-first century, where young people still asked, When can I do X? The Europeans usually said, with dread, How do we stop people from doing X? And X could be just about anything technological. Genetically modified food, screening for future disease risk, opening up the asteroids for mining of scarce metals, living longer through genetic tailoring, beaming microwave power from space, living half-time in virtual villages, sending a beacon signal to the stars. ISA was mostly backed by Asians and Americans. Euros didn't go into space—You could die! It would cost a lot!—and were busy shoring up their aging societies with plentiful taxes and fearful politics, eyeing the ever-growing population of Muslims in their midst... Shanna was quite glad to be out here, away from the swamp of Earthside. They sat around the ship's pedestal mess table, a polycarbon white circle. An awkward moment. Everybody beamed, glad to see fresh faces, but nobody spoke. An epic moment far from Earth. All sorts of firsts here. How to start? Then Viktor produced, improbably, two bottles of champagne to mark the moment. That loosened everybody even before lips touched liquid. Sure enough, the first socializing was about the latest Earthside news, most of it just the usual wrangling and angling that passed for politics. That done, like dogs sniffing noses, they relaxed. Shanna let the chatter run for about half an hour. They all had the zand interpretations, the spotty information on the Pluto biosphere. So they concentrated on reviewing the data, dancing around hypotheses. Viktor reported on his idea that the wavelengths received from farther out meant that the radiators were tens of meters in size, at least. Maybe that's just their antenna size, Chow-Lin said. Franklin agreed. After all, our antennas are pretty big, too. But, Viktor countered, the signals are from places where there are no worlds at all. Certainly nothing remotely as large as Pluto. They got into a technical discussion, and momentum flagged. Tit for tat, counters, hedges. Shanna let it run as long as she could bear before saying, abruptly, "What do you make of our ... hosts?" Viktor's face was veiled as he said, "You think big things make the small Pluto things?" Wow, he knows how to cut to the chase. "Somebody did," Shanna said. "We're not looking at natural evolution here, for sure." "Julia thinks so, too," said Viktor. "She is pretty good biologist. Has intuition." Shanna felt a stab of jealousy. Damn, she's good. How did she come up with it so fast? Jordin sent her a look she could not decipher. "We haven't actually discussed all this yet." Good old Jordin, undercutting my claim to first discovery, Shanna fumed. "The antenna-size argument," Chow-Lin pointed out, "just sets a lower bound. The creatures could be far larger. We're lots bigger than our eyes." Viktor said, "All assuming that the antennas are eyes—I mean, not a technology. Because we see no technology out there, just empty space." Julia's mouth tilted skeptically. "I rather think these zand of yours are not naturally evolved, but how can something bigger than a mountain—maybe the size of continents—make them?" "Not a clue," Shanna said. "But they didn't evolve on Pluto. That's not a biosphere back there, not a truly integrated system. It's a base camp, getting by on energy rations." "And run by electrical power that comes from way beyond," Jordin added. Julia's wary gaze did not alter. "No chance Pluto's been running that way for a long time?" Jordin shook his head. "It looks ... well, recent, contrived. The whole planet's got a narrow pyramid of life, few microbes, just a handful of amino acids—the minimum to make it work." "Built by something really strange," Shanna said. Viktor said, "So we invoke that rule, the knife something—" "Ockham's razor," Shanna said. She had been reading plenty of philosophy of science; it seemed a good investment, out here amid the truly weird. Plus science fiction, of course—lots of Arthur C. Clarke. "We've got two strange things, so maybe one causes the other." "Three strange things," Julia said matter-of-factly. "You got the transmission Earthside sent forty-two hours ago? They've decoded that low-frequency stuff that keeps washing over us." Shanna raised eyebrows and nodded reluctantly. "I can't follow it all, but... okay, one more mystery." "Getting to be lot of mystery out here," Viktor observed. Hiroshi nodded. "I've been running codes, along with the Earthside spectral analysis. They're—the big things—sending stuff in English, that's certain." This was new. There followed an extended discussion of how to decode. Mary Kay said, "That's my area. Transcendental Grammar, the Earthside cryptanalysts call it." Shanna said, "Isn't that secondary, compared with the basic biology?" "Not at all, Captain." Mary Kay's tone was just civil. How come? Shanna thought. Long-mission syndrome, as Jensen called it? Or do they all just dislike me? Mary Kay went on in a stiff, I-am-being-professional manner, "Whoever is sending, they don't use punctuation the same way we do. Commas, periods, semicolons, dashes—they all help organize the relationships between parts of the sentence, yes?" She smiled brightly, as though this was obvious, though Shanna had never thought of it that way before. "Semantic amplifiers, they are, adding precision and complexity to meaning." Jordin nodded, backing up his wife. "Increases the information potential of strings of words." "The trick," Shanna said, hiding exasperation, "is to figure out what they are, not just how they talk." "Not talk," Viktor said. "More like writing, by the time we—DIS and its handyman, Wiseguy—get done." Shanna said, "Because we can't hear it?" "Writing is a million times weaker than speech," Mary Kay said incisively. "No inflection, tone, smiles, winks, raised eyebrows, hand moves. Got to allow for that." Chow-Lin said, "Sort of like a hieroglyph competing with a symphony?" Mary Kay nodded, and Viktor said skeptically, "You think they have such things?" Chow-Lin shrugged, an example of what he meant. "There's plenty in the wave spectrum we can't decode. Look, I'm kinda reaching here." "And I'm getting lost," Shanna said. "I'm a biologist, not an information theorist. I think in terms of species, biospheres. I want to get down to what kind of creatures these things are." Julia said, "Our Wiseguy has been working on their low-frequency transmissions. We can eavesdrop. They call themselves the Beings." "Also the Diaphanous," Hiroshi added precisely. Shanna narrowed her eyes. "You should have sent this information over." Julia smiled. "We wanted to explain in person." Shanna said, "Diaphanous? Imagine—what a vocabulary." "I had to look it up," Viktor admitted. "And I'm human. Wiseguy said was good synonym for a whole constellation of meanings." Julia smiled at him. "Most of the time." "They must've been listening to us—to all Earthside—a long time," Hiroshi said carefully. "It is the only way to explain how it can—" "How they can," Jordin interjected. "Right." Hiroshi nodded vigorously. "How they can know so much of our language. English, anyway, though there were pieces in German—Ich muss diese Frage verstehen, as I remember. 'I must understand this question."' "Hey, join the club," Chow-Lin said, which got a laugh all around. "Maybe they have only one language." Shanna laughed, too, but made herself stay on the problem. Even though it was risky for a captain to think out loud. But here I'm just one of two. "So they eavesdrop on some Earthside broadcasts and include it all, thinking German is just some English they don't understand?" "Um." Hiroshi thought. "German's close enough to English, one of the two roots of it. Maybe they can see that. Incorporate the German?" Viktor blinked. "What a mind." "Minds," Jordin corrected him. "Earthside has gotten clear conversations in every batch. Interplay. Cross talk. We're overhearing them." "But they're sending to us directly in English, too." Viktor frowned. "Earthside has cracked their language," Jordin said. "Throw a few thousand crypters at it, you get results. We can eavesdrop on them now." "I am still amazed that anyone could figure out what so strange a thing was saying," Viktor said disarmingly. He gazed at Jordin and Mary Kay. "Can explain?" This brought them a beaming smile. Shanna knew well by now that Jordin was a frustrated professor and would no doubt be a real one someday. For now he was stuck being a mere astronaut. "The key is the chromatic scale. You know, the way notes are arranged on the piano. Our Western do-re-mi is a subset of that. Turns out, people worldwide put extra emphasis on tones that correspond to the notes of the scale. We like doing it. You record people talking, they put more energy into those special notes." Julia said, "Really? I never noticed." "Nobody does. We think it's natural. And it is! That's the breakthrough. Once we found this out, half a century or so ago, everybody thought it was a biological thing. Maybe we as primates heard bird song, invented some crude music, and after that learned to talk. Kept the same scale-note structure, see?" Shanna had heard all this before, but it was fun to see the others react. Sure, they'd gotten squirts from Earthside about all this, but who had time—or more important, given how badly written most of it was, who had interest—to make their way through it? The High Flyer crew was enthralled, champagne forgotten, except for Viktor, who sipped automatically. Maybe likes the alcohol a little too much! She would have to remember that. Maybe he was the weak link in High Flyer. "But for a long time," Jordin went on earnestly, "the math folks thought the scale itself came from harmonics, the ratio of numbers, all that Pythagorean stuff. Ancient history! Only it turns out to be right. See, the scale gives us pleasant harmony in music. That's why the twelve-tone garbage back in the twencen was the end of classical music." Blank looks all around. He hurried on. "They forgot the scale! We're conditioned by evolution to like the harmonics, the basics of music. So do dolphins, whales, birds! All of us." Viktor scowled owlishly. "Am losing you." "Oh. Sorry. A liking for harmony is apparently a universal—that's what I deduce from all these waves we've been getting. Whatever's sending them, they're singing!" "Can see data?" Viktor looked unconvinced. They spent half an hour looking at spectra on screens, Jordin and Mary Kay doing most of the talking. Jordin said, "Those intermediate-frequency plasma waves we detected coming out? Turns out there were plenty more picked up on the Deep Space Network—Goldstone and all those others, Parkes in Australia, you know—at least the higher-frequency modes, the upper hybrid ones, the descending helicons that go"—he whistled—"and they all fit. Lotsa data there. Plenty of cross-correlations. One big conclusion. In these 'Beings' speech—both the stuff they send us in English and the substuff, the cross talk they're having with each other—in that speech there is the same spectrum of harmonic emphasis." Viktor took another sip of champagne. Nobody said anything. Viktor's eyes squinted as though he were looking upwind into a gale. "Is meaning?" Jordin did not take this clue. "That the Beings communicate by a coding system that is like ours." In Viktor the light dawned. "So ... on that your crew—no, Earth-side—can hear their talk? And Wiseguy deciphers?" "Yes," Mary Kay said. "Soon we'll be able to talk back—through Wiseguy." Innocently Viktor said, "Can hear their inner thoughts?" Jordin blinked. "Those may be the plasma waves we're getting. Can't understand them, though." Julia said, "Thought isn't like singing, I suppose?" Jordin spread his hands. "Guess not—our thoughts aren't, right? Not mine, anyway." This got a laugh. He went on, "Maybe the stuff we don't understand is leakage. From whoever is sending the talk. I dunno." Vigorous head shake. "Amazing," Julia said. "We'll have to integrate our data with yours, through Wiseguy." Shanna let out her breath. It was going to be hard to break in on all this, but she had to get some things straight. "Say, let's take a break, gang. How about a tour of your ship?" This was fun, especially watching the 'bots working near the drive systems. Robotics plus nukes were the future. Cameras tracked the impromptu tour everywhere; the Consortium would wring every dime out of the footage. After an hour of this, when she and Julia were out of view, Shanna said, "You and I have some stuff to discuss. Don't want to bore everybody. Can we take it into another cabin?" "We call them rooms," Julia said slowly. "Seems better, more homey. Uh, of course, let's." They slipped away with a nod to Viktor, who was leading the tour, holding forth as host. Julia led the way through a circular hatch rimmed by pale emerald emergency phosphors. Shanna followed briskly. They came into a compact compartment she assumed was Julia's office, though no adornment of the inward-sloping faux-mahogany walls testified to this. There were contour chairs made of something pale effervescent blue and so thin that when she lifted it the 0.38 g field to face Julia, Shanna flung it toward the ceiling—and, startled, let the revolving chair spin with classical slowness into the corner. "Uhhhhh—oops." She retrieved the chair with one quick swoop of her left arm, flicked on the magnetic anchors, sat— And wondered how to start. She had fretted for weeks about this moment, but now, actually in Julia's presence, she marveled. The years had lined that face, but it was still the one Shanna had on her dorm room wall in college. This woman had changed space travel, revolutionized biological studies. Julia didn't just take part in the first manned mission past the moon but stayed there and made a home, back when astronauts were still hopping up and down from space like it was hot water they couldn't stand to stay in. Shanna swallowed, and set aside her hero-worship attitude toward Julia. Face it—you want to be like her, the benchmark of greatness. Which means you have to keep hold of your results out here, not let the media feature the Mars Couple every other minute... The absurd chair gymnastics seemed to break the ice between them. Unplanned, but who knew what the unconscious could do? Shanna had learned to go with the flow of events and surf on it when she could. It was the only wisdom she could pretend to herself that she had actually discovered, instead of just reading about, but maybe it was enough. Anyway—"Let's talk as captains, eh?" "I'm actually not captain," Julia said. "What? Earthside—" "I'm in charge of scientific matters. Viktor's Captain, but he and I are married, so we have split the duties. That's our style." "That's completely contrary to—" "Chain of command, I know. We cut a deal with Earthside. Whatever they want to call it, fine." Shanna kept her face as impassive as a firm wall against getting irked and losing it. "Because you're famous, you think you can abuse—" "Use, not abuse." Julia leaned on the slim black poly table between them. "Having the Axelrod name must've been useful in keeping your captaincy, eh?" "That was a little matter—" "Look, we're 6 billion klicks from Earthside regulations—" "And you and Viktor," Shanna spat back, "the oldest crew in the astronaut corps, you're going to be in charge?" "Not at all," Julia said mildly. "Experience does count, seniority might matter—but we have two ships, so we have two captains. As we're all on the same scientific expedition, we have to agree on methods, results, risks. Viktor and I have more experience than you—" "On Mars, which is an oven compared with Pluto. Why, we've had telepresence crawlers freeze right into the regolith, first day out! Took steam piped from the ship to get it free. I've had a lot more experience—" "Than we have at superlow temperatures, yes." Julia's eyes narrowed, her mouth twisted wryly. "But the biggest problem out here, the reason for the gigabucks spent to put us here at top speed, is the bow shock." "If it's a threat." Shanna's words rapped out. "Earthside weather hasn't shown any changes—except for the global warming, of course— even though the shock wall has gone from 100 AU to 42 AU in thirty-some years." "I know the data, for goodness' sake! But a hell of a lot of numerical simulations show big effects in the offing. The molecular hydrogen that's leaking into the inner solar system, it'll build up and start reacting with the free oxygen in our upper atmosphere." "And make water, big deal. Nobody knows—" "Plenty of energy yield there, that's the point. Heat up the upper mesosphere, and that drives big changes below. Screws up the stratosphere temperature profile, and pretty quick that heat moves down toward the business end, where our weather gets made." Shanna sniffed, nose turned up. "I see where you're going with this. We should be looking mostly at the shock edge, find out what's driving it. But Pluto is key here. That's what my, our discoveries show. Something's running all this, and it isn't stupid." "Nobody said the problem wasn't interconnected." "This isn't about dumb weather!" Shanna tossed her head back, her hair cascading slowly in the low gravity. "Okay, smart weather, then. Point is, the zand are pretty interesting. You were lucky to have stumbled into first contact with a self-aware species." Shanna felt her defensive walls come up. "Not stumbled—more like ferreted out," she shot back. "Some people thought I was just imagining the whole thing, that I was faking the data, even." "To be sure. The early criticism was unwarranted, but that's often what you'll get from Earthside. A lot of second-guessing and tall-poppy cutting." "Huh? I don't get it." Shanna looked perplexed. "Aussie slang. Grow into a tall poppy, people slice you off, whittle you down to size. Put another way, the Greeks felt their gods punished excessive hubris. It's the same thing." "Oh, I see. Hm. Never thought of it that way." "It helps not to take the automatic criticism personally. Save that for the important objections. The trick is to tell them apart." Shanna felt some of her anger ebbing away. In her defense against coming across as a hero-worshiper she'd forgotten that Julia had endured decades of scrutiny and bad-mouthing. Julia pressed on. "But we're moving beyond the zand, now, to contact with the movers and shakers out here—that's the main event. And if I may offer a bit of advice on the zand, you have to get over pretty fast your claim of exclusivity. You don't own the zand just because you discovered them. Hundreds of scientists Earthside are now reworking their research agendas to focus on the ecology of Pluto. No, make that thousands. Not to mention all the ink that will be wasted by the 'What does it all mean?' crowd." "You want to have a crack at them?" Shanna resented the rebuke. "Look." Julia sat back, shaking her head. "We can't start out like this, with a fight. We cooperate out here or we die." Shanna nodded, thinking furiously for a way around this woman, to hold her own. Go crying to Earthside? Not again. Try to marginalize her in future? Hard to do, on another ship. Okay, put that aside for now, but keep looking for an advantage. "Okay." "I know Axel—sorry, your father—spoke with you about our taking some Darksiders back with us." "Hey, 'Axelrod' is fine. I didn't see him much as a child." She made a wry face. "Yeah, I know he wants them. I even agreed to deliver some, if we can." She felt suddenly drained. Time to end this conversation. Julia sat, unmoving. Shanna made herself smile slightly. Bad beginning. She looks tired. My turn to try to lighten this up. "Hey, my father thinks we're both bad girls." Julia made a small, thin smile. "We are, no doubt. Maybe we're both a bit, how to say, heavy-handed? One thing you learn as captain is that there are very few problems that can't be helped by orders ending with 'or die.'" Shanna sighed. "I discovered that myself. My crew is irritated with me." Julia studied her. "You've been on duty too long. You're worn down." Shanna's eyes flashed. "Uh-uh. I and my crew are as fit for service as anybody." "I'm sure," Julia said stiffly, getting up. "Look, you and I haven't exactly hit it off—" "I'll say!" "—but let's keep it to ourselves." "Right. Professional." She cocked a wry smile. "I guess this day was a total waste of makeup." This made Julia smile faintly, grudgingly. "It wasn't wasted on my crew, believe me. The guys have had only two women to look at for a year, me and Veronique." "Same on Proserpina, me and Mary Kay, only it's been years." "Not easy, working in tight quarters. The hormones get going." "Sure do, and not just among the men." "Ha!—I'll say. Luckily I have Viktor." "Yes, a husband. I neglected that point before shipping out." Julia smiled without mirth. "You may not know this ancient history, but our being married was a, shall we say, 'condition of employment.' Marry or be replaced." "Huh? That's Victorian." "They felt that an unmarried woman couldn't go into space for years with three men." "Who? The Consortium?" "No, Axelrod—your father." Shanna opened her mouth, closed it. The silence stretched. Julia said softly, "Luckily it's worked out terrifically. We made it alone on Mars for two years without killing each other." Shanna just stared. Julia looked tentative, half turned, then looked back. "A piece of advice..." "In dealing with the men?" "Yes, and not just for the men." A thin smile. "Always keep your words soft and sweet, just in case you have to eat them." 5 STRANGE SYMPHONY Julia was glad to see them go. She had thought that she would be very glad to see fresh faces, but they wore out their welcome in a day. Maybe she was getting too old for this spacer stuff. Or maybe her diplomatic skills were wearing thin. Had that been behind the trouble with Praknor? Anyway, the Shanna woman was abrasive, self-obsessed, smug—and those were her good points. Julia suspected that in a pinch the woman might also be careless, the one sin reality never forgave. The first hour had told the tale. Of course, they had more techy discussions, crews getting to know each other, all aware of the collaboration to come. But the edgy distance between herself and Shanna had been an undercurrent beneath every moment. Everybody felt it, but thank God, didn't talk about it. Until they were gone. "You need rest," Viktor said flatly when the lock clanged down. "Yes, sir, Cap'n, sir." "Really." "Point taken. That Shanna really wore me out. The way she tosses her hair back, showing off—arrggh! That's always irked me. Worse than dealing with that Praknor—hey, think it's a generational thing?" "Hope not. Am not ready to be 'old fuddy-duddy generation.'" She looked at Viktor appraisingly. "I'd choose your old fuddy-duddy over any young guy." "According to Praknor, many women Earthside agree with you." "Ah, the sperm king!" She laughed and collapsed into a lounger. The logistics and tech issues had dominated everything, as one would expect of astronauts. But somehow all the time she was seeing their ship anew, through the others' eyes. They thought it wonderful, ornate, opulent compared with their fission-driven craft. Fat cats of High Flyer. Well, fair enough—fusion had come available at just the right time to make High Flyer a whole step up, and it showed. A great way to sail into the abyss, indeed. High Flyer's designers hadn't much consulted any of the future crew about interior design—it had all been done on the hustle—so it reflected Earthside's latest notions. Appliances and even furniture looked as though they had grown there—ductile, rounded, even drippy as if recently melted. The style was called blobjects, and this look made them seem organic, natural. But, in fact, they were the opposite, stuffed with smart chips that processed data without letup. If a crew member was carrying a virus— no medcheck caught all of them—High Flyer wanted to know it. If you had fallen asleep in the common room and were about to miss your watch, the room noticed and High Flyer beeped you awake. Even in the stringy little microgravity "beds" at the axis for low-grav sleep, they could mommy you to death, if you let them. Like many of Earthside's cities, the "smart ship" embraced its inhabitants, keeping tabs and worrying over health, safety, supply and demand of air, moisture, heat, power, the works. She had found it weirdly claustrophobic at first and for weeks did not sleep well, feeling that some thing was watching. Then as they flew at great speed into cold, dark spaces with no humanizing glimmer of promising light, High Flyer seemed to become warm, comforting, restful. Home. Which was the idea of her designers all along. "The Vid Kids hauled off their stuff," Veronique reported briskly. She was trim but managed to have an Earth Mother persona, a real trick in the astronaut corps. She was the crew comic, too, hearty when all the rest were withdrawn. Valuable beyond measure, on a long mission. Viktor nodded. They had labeled the Proserpina crew with that name because they had anxiously asked for the latest vids the High Flyer might have brought—indeed, it was a big part of the "mail" they'd asked for from Earthside. "Maybe they don't like their own company too much by now," Viktor said with a wry eyebrow lifted. "How long have they been gone?" Veronique asked. "Two years, five months," Julia supplied. "Time wears out the best of friends. Be grateful we're riding a fusion torch, not a fission one." "They also tried out the smart-ship functions," Veronique said, stabbing at the air irritably. "One of them I found ordering a martini from ship's stores!" "I know, I came in after you stormed out," Julia said wanly. "And ship was delivering, too. I never thought to ask before." Veronique said sharply, "You should've protested! Hospitality is one thing, but—" "Yes, is waste of ship time and resources," Viktor said mildly. "But is diplomacy here, too." Veronique wasn't buying this, Julia could tell. She was a brilliant all-round type, good at six different skill sets, but a bit wearing when she got on a cause. Viktor started speaking in his mild, calming manner, and she left that job to the resident expert. Julia needed to get away from them all. Far away. Decades of Mars duty had taught her to create her own privacy. Nothing like cramped quarters to concentrate the mind! She had learned to disappear within herself, walling out sounds and smells and vibrations, to create a still, silent space where she could live, rest, think. In the continual noise of the hab she had learned to hear well, diagnosing the ship's vibrations. But just as well, she knew how to listen carefully, or to deliberately not hear. An essential skill, taking years of daily practice to master. Living in space created rituals and customs, even taboos, to keep buffers between people. This extended even to language, allowing her to politely avoid any question she didn't want to answer. So she had insisted on this cabin artfully crafted of paper walls and tatami mats and small, delicate decorations. Simplicity made it easy to stay within her mass limit. And illusion helped. If it was high-resolution enough, even knowing that a view was phony did not rob it of its effect. She sat cross-legged. Watching a sunset on a personal wall screen was perfect for this. Listening to the interior rain—the fall of vapor sheets on each wall, images playing on their thin surfaces—brought delicate splashes into her concentration ... and the present vanished. The simple thatched hut sat on thick hardwood pylons above a sweep of immaculate white sand. Maples surrounded it, and she approached it on stepping-stones so perfectly set in the moss that they seemed to have grown there. On the veranda were sitting cushions, for seldom would anyone want to sit inside, in the single room of hewn beams and rustic screens. This ceremonial teahouse was for tea and thought alone. All hers for now. She shared it only with Hiroshi Okada, and he was on 'bot duty. Crew needed their retreats, and Julia had in the long decades on Mars come to understand well the Japanese cultural way of dealing with an ever-pressing crowd you had to get along with. Getting away was the only strategy. She and Hiroshi had pooled their allotted ship space in this way. She rose and entered the massless retreat she had fashioned herself—the essentials of a classic garden: stone, water, bridge, pavilion. They all hung in the spaces of her own private place. Only visual, but still telling, restful. It was a cylindrical volume of falling mists, each a thin translucent sheet that descended in the light air as holographic projections played on its surface. A few feet away the pleasant moisture tingled in the nose, and the images framed the room into the Harmonies Garden of Wu Xi, a classic spiritual retreat. Cinnamon camphor trees perfumed the air. A tinkling waterfall splashed on worn stones. She sat in lotus position on a tatami mat and watched the cascading stream leap over convoluted limestone. The walls had curious cylindrical holes that had been worked by flows millions of years ago. Stone. Water. Bridge. Pavilion. Until her next watch. Three days later, the bare nugget sun now lost in the glare of their blaring fusion torch, she sat with Viktor and Veronique and tried to make sense of their new discoveries. Veronique played them the complex waveforms, souped up from their original very low, infrasound frequencies around ten kilohertz, into the audible. It was the strangest symphony anyone had ever heard. At times the haunting low notes were like the beating of a giant heart, or of great booming waves crashing with aching slowness upon a crystal beach, playing the ceramic sand like a resonating instrument. Julia felt the notes with her whole body, recalling a time when she had stood in a French cathedral and heard Bach played on the massive pipe organ that sent resounding through the holy stone box wavelengths longer than the human body, so the ear could not pick them up at all, but her entire body vibrated in sympathy. It was a feeling like being shaken by something invisible. It conveyed grandeur in a way beyond words. And now the thing that made this strange symphony was tolling like an immense bell that itself enclosed an entire cathedral, and used it for the slow, swinging clapper. Into her mind came the memory of a whale she had sighted offshore Sydney, breaching fully into the summer air. The long shape had burst nearly free of the sea, flukes turning lazily in the sharp sunlight. She had bought many recordings of their songs. Even if they had simple messages, she found them haunting. Sitting back, she tried to envision what would radiate waves tens of kilometers long. To such creatures, humans might be as inconsequential as the lice that pestered the skin of a blue whale. The longest wavelengths High Flyer had detected (barely) were truly gigantic, up to a million times longer than those that ushered in classical radio astronomy. A century ago the center of the galaxy was detected by an amateur astronomer, Grote Reber, using a backyard dish strung from ordinary household wires on a wooden frame. He used wavelengths as big as a human. What could humans glimpse in wavelengths a million times larger? Julia reminded herself that it was only because they were out here, beyond the dense plasmas blown out by the effervescent sun, that they could detect anything at all in this region of the electromagnetic spectrum. By accident High Flyer had strung its antenna elements along its great length, so they were seeing with an "eye" effectively hundreds of meters long. Yet even such an aperture could sense wavelengths of many kilometers only dimly. But they had detected those waves, and that had changed everything. The great virtue of discovery, she mused, is that it raises more wondrous questions than it answers. She had a quick image of humanity's perceptual universe, expanding outward in a sphere from the sun. To be sure, they came to understand what lay in that increasing sphere's volume, in time. But the price—or reward—was that the surface of that sphere, the edge of the unknown, also increased. There was more known, but always more to be known. Yes, she thought, and the unknown can masquerade as the unknowable. She thought of the actual sphere of the solar wind and wondered if the sun at its center kept these huge beings at bay. Not so long ago, humans kept wolves prowling at the rim of their campfires—but not venturing farther in—out of fear. Did something like that keep these huge beasts from plunging into the realm of the planets? And if so, should a mere ship venture into that dim twilight beyond the fiery campfire, where truly gigantic wolves might lurk? 6 TINY THINGS Serene sent from afar. She was cautious and wanted no part of any strange tiny things that intruded. Forceful said to Instigator. Instigator said, her intonation deflecting criticism. Mirk's signal worked with worried low notes. Sunless said. Ring charged. Instigator said sharply, Mirk sent, Chill said sternly. Instigator sent. Chill said. A chorus of voices agreed. Subharmonics made a droning chorus of dread. Recorder said slowly, as bespoke its age, 7 SPIDER NET Viktor was irked. "Damn! We're flying straight, straight as arrow—and they're not." Julia sat down in the parallel acceleration couch and for some reason, staring at the sprawled array of data and indicators and views fore and aft, remembered when she had been a teenager and had lived in a comfortably neat world, had believed utterly in the civilizing power of fresh lipstick and combed hair and not talking out of turn. Things had changed. "Not being proper and orderly?" she asked him lightly. "Making this plasma wire trick hard to work." "They're not holding to course?" "Getting buffeted, they say. Lighter ship, could be so." "Display the net?" Julia asked Veronique. She did. Proserpina was jiggling slightly, yes. The ships were thousands of kilometers apart, two piercing flames in the obsidian void. Proserpina's fission glow was muted, its plasma not long lived. High Flyer's flared brilliant blue-white behind them, fusion plasma alive with a vibrant incandescence formerly seen only in the hidden hearts of suns. Except—at higher resolution the image picked out tendrils of snaky blue, each a thread connecting the ships. A spider net of plasma strands, the only way to listen to the deeps beyond. A grid for receiving waves of a scale no one had ever contemplated until now. Their plan had been worked out by myriad plasma physicists sweating over test chambers and calculating pads, back Earthside. The first idea had been to eject a wire with tiny rockets at both ends. Fired off, they would uncoil the wire from a central processor and power supply, all left in High Flyer's wake. When the rockets played out, they would detach, leaving a wire a thousand kilometers long. This would unfurl the largest simple dipole antenna humanity had ever made. In the 1890s Marconi had made simple antennas like this, though those were about the size of himself—and he had changed the world. This time, a mere 150 years later, they might use such an antenna to discover beings beyond the imagination of anyone in the nineteenth century—except, that is, H. G. Wells. It had been a pleasant image when Julia first heard of it. Stringing wire, like the radio pioneers. But too awkward, the engineers decided; too ... well, massive. Even hair-thin wires thousands of klicks long add up. So their ships carried plasma guns, not wires. The guns were marvels of artifice, able to emit steady streams of barium ions and their court jesters, the electrons. These beams ran from High Flyer to Proserpina, slender and elegant. Their own electrical currents provided the magnetic fields that confined them to threads a bare centimeter wide. Unlike bulky wires, which can stretch quite little, twist only a bit, and often break, these plasma beams inherited the infinite flexibility of magnetic fields. These wrapped themselves around the currents that passed between ships. The bands of invisible magnetic loops could flex and swerve and contort to accommodate the varying distances between the huge spaceships. They kept contact going. But they were also simply current carriers, like wires, only far more insubstantial and vulnerable. They worked as the effective wires of an antenna, stretched between the speeding ships at velocities of tens of kilometers per second. These plasma pinches could pick up the waves incoming from the outer reaches, just as ordinary wires could. Processors aboard both ships then deciphered the oscillations in current and voltage as signals. H. G. Wells had never thought of this, much less Marconi. "But what could make Proserpina jounce around?" Julia asked. "This is empty vacuum, after all." "Not quite," Veronique said. "We're getting close to the bow shock. Ah yes—there, that ruby glow ahead." Diffuse radiance filled half the sky. "But that's just where the plasmas meet. Thin stuff." "Put it into a resonant wave, just about the size of your ship, and the effect piles up," Veronique said. "Like wind forcing oscillations in a bridge. Acting all along the side of Proserpina, it can hit that resonance. Or maybe just as bad, it's like a steady wind on a car. The faster we go, the bigger the effect." "Ummm." Julia frowned, alarmed. A threat in empty space? "Should we dive straight into the nose of the bow shock?" "Da. Is closest part, the nose," Viktor said. "Like the prow of a ship, bow shock spreads out from it. We want to know what's up, best place to go." Julia reminded herself that Viktor was captain, even if she was sleeping with him. She would keep her worries to herself for now. "If it can shove Proserpina around that way..." "We are much bigger, heavier." Viktor grinned wickedly. "So is Proserpina. May lose the antenna, yes, but need the shock data. And will be fun. First persons to cross into interstellar space!" Julia laughed. "Once a pilot, always one," she whispered to Veronique, not so soft he wouldn't hear. "Not just for thrill," Viktor said soberly. "You haven't forgotten that we're down to 28 percent on water?" Veronique said timidly. Viktor glowered. "Of course not. We can run another month on that." Veronique said evenly, "We're not supposed to run less than 20 percent." "We'll find iceteroid, no problem," Viktor said decisively. "I thought they were supposed to be pretty far apart out here," Julia put in. "We passed one a couple weeks back, though." Viktor said bearishly, "We do not turn back." "I didn't mean we should," Veronique said. "Just—" "After we blow the nose"—Julia grinned at him as she said it— "we'll look for some ice to melt down." With a curt nod Viktor said gruffly, "What I had in mind." Julia could see that even after more than a year of crewing with them, Veronique was still working out how to deal with a married couple who could read each other's every unspoken cue. "Check spectrum locus, eh?" Viktor said, pretty obviously trying to change the subject. Veronique called up the mapping their plasma-net antenna was making. Spotty, but the conclusion was clear: "Most of the really long wavelength stuff is coming from around the nose," Veronique said. "It's not just noise?" Julia asked. In answer Veronique flipped on the audio. Long, humming chords. Thin leitmotifs atop that, skittering down the scale. A spray of sharp notes like harsh shouts in a distant fog. "Working on the decoding?" Viktor asked, eyes never leaving the displays. "You bet," Veronique said crisply. "I think I can break it into words soon." "Words already? You're using just the SETI codes?" Julia asked wonderingly. "Well, with a bit of spin of my own." Veronique grinned. "I think the other side is making it easy for us." "The ... source?" "Sources. Near as I can tell, there are plenty of them." Julia blinked. "You can tell them apart?" "Except the rude ones. They talk over the others." Viktor nodded. "Too many of us like that." Julia was amazed. Decoding the low-frequency, long-wavelength signals had been a feat of intellectual daring. After all, what could humans share with them? If the things that made the signals were large, in the depths of space beyond stars, maybe they were not even used to stable structures. She sat back and mused. One could think of them as being like jelly creatures maybe, awash in a dark environment. They might not think mainly in terms of numbers, but of geometry. Their mathematics would be mostly topology, reflecting their concern with overall sensed structure rather than counting or size. They would lack combustion and crystallography but would begin their science on a firm foundation of fluid mechanics, of flows and qualitative senses. But others Earthside argued that no matter what the environment, creatures that made it in a harsh place would evolve basic ideas like objects, causes, and goals. Still... what objects were hundreds of kilometers in size? Iceballs, all right, but creatures? And what about causes? Even in quantum mechanics the idea wasn't crystal clear. Still, every environment had limits. Scarcity would bite, forcing the idea of realizable goals. Hardship would reward those who caused goals to come to pass, acting on whatever objects the vast creatures could see. So maybe there were universals among intelligences, even if a bit abstract. The critical point had come with the realization that the harmonic structure of sound had a numerical key, that the notes of the scale were the ratios of whole numbers. This unlocked the code. Do-re-mi, a child's rhyme, had turned out to be fundamental. A noted twencen physicist, Richard Feynman, once said, to the horror of some philosophers, that "the glory of mathematics is that we do not have to say what we are talking about." So sense could fly on the wings of mathematics, of encoding, without having to point to common, shared objects—chairs, sunsets, bodies—to make a sentence that made sense. Beyond that, the argument descended into ornate relays of mathematics. Or maybe it ascended; anyway, Julia could not navigate the logic. "What are they saying?" she asked. "Sounds like..." Veronique paused. "Maybe warnings. Maybe threats." Viktor grimaced. "Hard to know which I would prefer." "Wiseguy is having problems. Context related. But it can translate to know they're talking—singing—about danger." Julia had a momentary vision—an intuition, but from where?—of a spongy, swarming thing like a cloud. Yet also a thing of currents and whirling motion, a thinking tornado. And a thin extruded tendril of it—hesitant, flexing, touching, feeling ... inward. A giant's rub. 8 CASCADE The ETERNAL COOL GALE came howling in from Upstream. To meet it, a constant roar of the starwind came soaring out from the eternal, prickly Hot. Sheets of heavy spray slashed at the Beings as they came to feed. Hot plasma streamers curled and smashed howling against their outer wings. The curling waves were steep and breaking into coils. Some of these gnawing whorls were large enough to engulf an entire Being, and when one did, it carried the hapless, rubbery shape of intense magnetic order down a slope of ravening turbulence, to dash it into rivulets that scoured its hide. Then the Being would be buried gloriously in the food it sought— gorged on it, lacerated by the very energies it needed to live. This paradox dwelled at the center of their art and philosophy, the contradiction between feeding and being ravaged. At the worst, not merely to be flayed by the frying of dying magnetic fields but to be cut, seared, feathered, and frayed. Diminished. Most Beings knew how to skirt the worst of it, skating the edge while absorbing magnetic whorls and digesting them into stronger fields within themselves. They valued the helicity above all, the twisted fields that carried the tight strands like rubber bands, that enabled a Being to confine itself. Sinew gave strength. Yet the awesome power of the Cascade never deterred, for this was the peak joy for them all. They rolled and basked and breached in the slide of the interstellar plasma, a torrent eternally incoming, smashing against the resolute wind from the distant Hot. Together as always, Mirk and Sunless were hogging over the crests of blithe helicity, sliding down their slick slopes. Their very perimeters sagged and staggered under the chop, absorbing energies and being seared by them, a thousand eating tongues forking into their magnetic skin. Joy came sliding in with the spitting fear, always. Some Beings dreaded the necessity of the Cascade. Others longed for the shaking, slamming, pitching verve of it. Chill and Dusk broke with glee through mountainous crests, skating on the seethe. Battered, they lunged into the roar of magnetic storms and spitting ions, rolled and swamped by them, besting them with cries of triumph. Hissing fires lit in their bufferskins. Swimming, they sang. Recorder said, feeding sedately on minor vortices. Ring chimed. Forceful said. Ring sent in diplomatic calming notes.