Stephen Baxter - The Full Story of the Firstborn Assault on Mars

She was alone on Mars.

Indeed this was not her Mars. Most of this time-sliced world, for all its cities and canals, was cold, arid. She was not comfortable here. She built herself a shelter at the Martian north pole, a spire of ice. It was beautiful, pointlessly so, for there were none but her to see it.

When she saw the array of symbols burning in the ice of Earth, she was consoled. They gave her a shock of pleasure, a confirmation that though she was cut off from her own kind, mind was here in this new system with her, a mind on some level like her own.

But it was a cold comfort. She was the only one of her kind to have come through the crude time-slicing which had created this sampled copy of her home world. It struck her as an extraordinary misfortune. Or, at times, it seemed to her rather a great fortune, for she was the only one of her kind ever to have viewed this pocket universe, this other solar system with its array of blue worlds.

She was not really a 'she'.

Her kind were not sexual as humans were, though she had been a mother; she was more 'she' than 'he'.

Before her stranding here she had never been alone, for her identity was less sharply defined than a human's. Yes, her body was a community of cells, but her form was unfixed, flowing between sessile and motile stages, sometimes dispersing, sometimes coalescing. She was more like a slime mould, perhaps, than a human. So she was never alone in that she was intimately connected to the tremendous networked communities of single-celled creatures which drenched her Mars. Nevertheless she was a pole of consciousness arising from those communities, and fully self-aware.

There had only ever been a few hundred thousand of her kind, spread across the seas and dust plains of Mars. Though they labelled the phenomena of the world around them, the Martians had never had names for themselves; there were only ever so few that names were unnecessary. She had been aware of every one of her companions, like voices dimly heard in the echoes of a vast cathedral. And she was very aware that they had all gone, all of them.

And the approaching Firstborn weapon, Mars's own Q-bomb, had gone too. That was the other thing she was aware of, from the moment of the discontinuity that had brought her here.

She had been working at the Martian pole, tending the trap of distorted spacetime within which she and her fellow workers had managed to capture the Firstborn Eye. In senses enhanced to 'see' the distortion of space, the coming weapon was very visible, at the zenith, driving straight down from the sky towards the Martian pole.

It had only been a few of Mars's days before the impact had been due. The consequences had been well modelled. It would mean the end of complex life on Mars, the end of all possibilities. Some had already escaped this dread fate, cutting themselves painfully out of the great planetary webs of life. Others scrambled to leave. She had volunteered to stay, to witness the end, and to continue the last project of trying to understand the Firstborn, the motives of those who were inflicting such a devastating blow on a living world.

And then came the time-slicing. The Eye remained in its cage. The Firstborn weapon was gone.

And she was alone. A toy of the Firstborn. Resentment seethed in her.

The symbols scrawled into the ice sheets on Earth, picked out by fire and smoke, were easily visible, and instantly recognisable. But even before the array of symbols was lit she had been fascinated by Earth, or this time-sliced copy of it, and the life forms that swam and crawled and flew there. For her it was like a glimpse into the future, a vision of how life on Earth had evolved in the long aeons after her own kind had succumbed to the intervention of the Firstborn.

And of course every living thing on Earth was a cousin of her own, for life on Earth had evolved first on Mars.

In her time the very young Earth, so much more massive than Mars, was still a water-world, its deep lifeless oceans mud-brown with sediment, its thick air laced with steam, methane and carbon dioxide. Mars, smaller, lacking tectonic activity, and so much further from the sun, had more quickly cooled from the fires of its formation and dried. Very soon there was dry land, and Mars was a more welcoming crucible for life. In warm crater-lakes, and in the complicated environment of lake shores and tidal plains, life was created, stewed from organic material that was scattered over all the young worlds by the comets - or perhaps that first life blew in from some other, still older world; her people had never been able to determine the truth.

From the beginning the harsh caress of impacts blew Martian life into space and shed it over Earth and Venus, where it began independent evolutions. With time the great branches of solar life were still cross-linked by more meteorite transfers, but as the age of massive bombardment passed these transfers became more infrequent. The great sharing was in the beginning, when the worlds were young, and as much as half a tonne per year of material could be transferred from Mars to Earth.

But young Venus and Earth were hot, drowned. It was on Mars that evolution proceeded first, and fast. Soon the first photosynthetic organisms, ancestors of creatures like cyanobacteria, were pumping oxygen into the air, a poisonous cataclysm that caused the planet's first great mass extinction among its methane-breathers - and yet led to the possibility of still more advanced forms of life, fuelled by oxygen's potency. But the Martian environment was full of compounds that would bind the oxygen and so draw it down from the air: volcanic gases, the iron of the crust, and organic sediments, beds of tiny, rotting corpses. These reducing materials had to be used up before oxygen could accumulate in the atmosphere, and soon were. The crust rusted red, the volcanic gases dwindled, and the organic materials were buried in beds of sediments on the bottoms of the lakes and oceans.

On Earth it was different. There continuing tectonic activity churned up the organic sediments, and the endless volcanism spewed up more reducing compounds, that relentlessly removed oxygen from the air. It would take three billion years before sufficient oxygen accumulated for multicelled life forms to appear on the Earth.

On Mars, it took only a thirtieth part of that time.

The great experiments of life on the worlds of Sol ran in parallel, but with different outcomes. On Mars as on Earth there emerged three great domains of life, with equivalents of bacteria, archaea, and the viruses which were parasitical on the others. As on Earth the bacteria diversified into an array of remarkable biochemical machines, and the archaea colonised every environment available to them, even the roiling-hot interiors of the deep rocks. With free oxygen a great new experiment began, as the three domains fused to create a new order of life, called on Earth the eukarya, the grouping which would one day include fish and apes and humans.

When intelligence rose on Mars, there was enough similarity with the Earth of the age of mankind that some features of their civilisation were similar. The Martians manipulated their environment; they lit fires and built cities. But on a more fundamental level Martians were not like people. The Martians had a greater fluidity of form, a deeper interlinking to the underlying communities of single-celled organisms, and more permeable species barriers. When Martians bred, as much genetic information was transferred horizontally between individuals as vertically from 'parents'.

Martian individuals were harder to distinguish from each other and from their progenitors than humans, for they could share body parts. They were long-lived, slow-moving, contemplative. They were wise. For generations human astronomers would think of Mars as a world much older than Earth, inhabited by a race of philosophers. In a sense they were right.

And this fluidity of structure made for a faster evolutionary response to changes in environment. The last Martian understood that Mars would continue to cool rapidly; a mere half-billion years after her time the oceans would have frozen over, the water retreating underground to chill aquifers, or lost to space. The time-sliced Mars contained samples of what the planet had ultimately become, and the last Martian had inspected this relic with dismay: the atmosphere only a thin veneer of carbon dioxide, only traces of frost in the beds of the vanished oceans, and dust storms towering fifty kilometres tall over an arid landscape sterilised by the sun's ultraviolet. But, given the chance, perhaps her kind could have adapted even to these tremendous changes of conditions, learned to live on a Mars reduced to an arid desert.

But her kind were not given the chance. It pained her to study the rest of the Mars she had inherited. In places the cities of her kind still stood, abandoned, their lights burning. But her fellows were gone. And in places where more recent slabs of Mars had survived, when she dug into the arid, toxic dirt, she found only methanogens and other simple bacteria, thinly spread, an echo of the great rich communities which had once inhabited this world. And yet, she thought sadly, these scrapings were her own last descendants.

Of course she understood the implication of the Earth creatures' scraping of the symbol array in the ice. Those on Earth had no wish to submit to the Firstborn's hammer blow. Nor had the Martians.

The last Martian understood. She pondered the signal from Earth, and considered whether she should act. Whether the Firstborn should be thwarted.

The approach of the Firstborn weapon to Mars had stimulated an explosive study of cosmology and cosmogony and spacetime physics, all of which were wrapped up in the Q-bomb. No way had been found to deflect or defuse the bomb. But a rapid mastery of the manipulation of spacetime had been achieved. When the Firstborn's hateful Eyes had appeared, more spacetime artefacts popping up all over Mars so the Firstborn could watch the destruction of a planet-wide culture, that new mastery had been used to trap an Eye. And before the Q-bomb could reach Mars, crystalline arks had lifted from the banks of the canals: ships that cruised on spacetime waves, built by a culture that had never used chemical rockets.

The Martians had not wanted to see their culture go to the fire for the sake of a neurosis born when the cosmos was young. So they fought back, and tried to escape.

Just as the creatures from Earth were trying to fight back now.

There was only one choice to make.

It took her seven Martian days to make the preparations. She believed that by imploding her spacetime cage she might destroy the trapped Eye, or at least cause it severe harm. And since all Eyes were connected to all other Eyes, it could be a way to assist the creatures of Earth in their struggle.

At any rate, it was the best she could do.

Unfortunately the implosion would damage her spire of ice. She began the construction of a new one, some distance away. The work pleased her.

The spire was no more than half-finished when the gravitational cage clutched at the Firstborn artefact, a fist enclosing an eyeball. Mars's gift to Earth.

There was only one Eye, though it had many projections into spacetime. And it had many functions.

One of those was to serve as a conduit of information.

When the Martian trap closed, the Eye there emitted a signal of distress. A shriek, transmitted to all its sister projections.

The Q-bomb heading for Earth was the only Firstborn artefact in the solar system, save for the Eye trapped in its Pit on Mars. And the Q-bomb sensed that shriek, a signal it could neither believe nor understand.