Moonseed

1

A day later…

Well, after a day, the Moon hadn’t exploded, but outside the lava tube, the wind and rain kept on. The roof of the inflatable shelter sagged, because it couldn’t sustain its own weight over the pressure of the new air outside. It made getting around harder; Henry had to shove billows of fabric out of his face the whole time. It was irritating.

They were both hot and miserable, and they bickered.

But then the rain stopped, or at least tailed off a little. They could hear it, even inside the shelter.

So Henry was going to get to go outside, to explore the new Moon. He felt like a kid, waking up on the morning after a snow fall.

He put on his blue coveralls, regolith-stained gloves and Moon boots. He checked over his POS, his portable oxygen system. There were straps for him to fix the pack to his chest, and more to tie on his scuba-diver mask. There was the smell of rubber, of stale sweat, inside the mask; and immediately he put it on it started to mist up.

Geena watched him. Behind her, their lunar surface suits lay abandoned in a corner, greyed fabric sagging, like two fat men slumping side by side; Henry’s fishbowl helmet stared at him accusingly from where he had dumped it.

She said, “You sure this is going to be enough?”

“I’m sure. Believe me. Haven’t I been right so far?”

“About the Moon, maybe.”

He eyed her. They were going to be stranded together here for a while yet.

“I think we need to get out of here before we kill each other,” he said.

“Amen to that.”

Geena ran one last check of the shelter’s systems, and then followed Henry out of the cramped airlock. They carried their comms unit between them.

Henry looked up from the base of the rille. Before the nuke, he recalled, he’d been able to see stars up there.

Now, things were different. Now, the narrow rille was roofed over by a slab of grey sky, fat with cumulus clouds that looked low enough to touch. The murky light diffused down over the walls of the rille, and his blue coverall.

It was still raining, in fact, a slow drizzle of fat drops that hammered on his POS faceplate and rapidly soaked into his coverall.

But he wasn’t cold. In fact the air was hot.

…But it was thin, just a layer of carbon dioxide, nitrogen, water vapour and trace gases amounting to maybe a sixth of Earth’s atmospheric pressure. Like a mountaintop.

You wouldn’t want it much thicker, in fact. The gravity was one-sixth G, so to get the same air pressure as Earth you’d need a column height six times that of Earth’s. And then you’d suffer from a lot of haze and a greenhouse effect, all that cee-oh-two trapping excessive heat.

So, thin and dry was best, just the way it should be. It was as if they had been transported to the summit of a mountain two hundred and forty thousand miles tall, wrapped in comet air.

When he took a step, he squelched in red-brown mud. It was soaked regolith. He could swear the rille was a little deeper than it had been before — well, perhaps it was; perhaps the deeper regolith layers had collapsed. After a couple of steps it was hard to lift his boots, low gravity or not, so caked were they in clinging lunar mud.

He reached the walls of the rille. They were shallow, but now they were slick with mud, and their profile seemed to have changed. Further down the rille he could see evidence of landslips, great swathes of mud which had come shearing off the rille walls.

And, down the centre of a valley cut a billion years before by a flow of lava, a rivulet of water was gathering. It was the start of a river which would gather, Henry knew, until it pooled with dozens of others in the great sea that must be forming in the Oceanus Procellarum.

Geena shivered.

He turned to her. “You okay?”

“I think so.”

Her voice sounded thin… and then he realized that he was hearing her, her voice faintly transmitted by the thin new air.

“How about that. I can hear you.”

“What?”

“Never mind. You shivered.”

“It’s just being out here,” she said. “In the open.”

“And not on Earth. I understand. We’re the first humans to walk around unsheltered like this, on another world, in all our history. We’ve had nothing to prepare us for this. If you weren’t scared—”

“It would prove I’m even more unimaginative than you think already?”

“I didn’t mean that.”

“You’re so patronizing, Henry.”

She walked away from him, her feet leaving great glopping craters in the mud. After three paces she slipped, and landed on her butt with a slow-motion splash; gobbets of mud sprayed up around her.

Henry knew, absolutely, imperatively, he must not laugh.

She growled. “Probably the low gravity. Reduced friction.”

“Probably.”

“Watch your step, Henry.”

“Copy that.”

They powered up the comms unit, and set up its low-gain antenna. They put headphones to their ears, and Geena started sending an automated telemetry feed; Henry could hear static, and the chatter of the telemetry.

For long minutes, there was no reply.

“Don’t give up,” Geena said doggedly.

“Yeah. There’s a lot of electrical activity in this atmosphere. It must be hard to punch a signal through—”

The static broke up. It was replaced by a chaotic noise.

At first Henry thought they were picking up the crackle of lightning from some remote storm — could an ionosphere have formed here so quickly? Then his mind resolved the sound.

Cheering.

It was human voices, raised in cheers and whoops, either at Korolyov, or Houston, or both; he couldn’t tell, and right now didn’t care.

His eyes prickled. As if he was the one who had just found a planet full of people who were alive after all, and not the other way around. Damn it.

They climbed the rille wall.

It was a lot harder than it had been before. The thirsty regolith had soaked up the rainwater to a depth Henry hadn’t anticipated, and the wall had pretty much turned to a shallow slope of slippery mud. It was impossible to get a footing, or to grip with gloved hands, and they slipped back almost as much as they made headway. After a few minutes, Henry dumped his mud-caked gloves in frustration, despite Geena’s admonitions.

Eventually Geena found a way of zigzagging up the slope, like a mountain path: it was longer, but her footing held in the low G long enough for her to take each step and climb a little further.

Henry sought a more direct route. One of the many landslips had exposed a gutter of lunar bedrock. Henry found he was able to run at this, scrambling at the rock to get purchase before his feet slid out from under him, until, by sheer momentum, he’d reached the top of the rille.

Side by side, panting so hard their oxygen masks were steamed up, they stared out over the Moon’s new landscape.

It was a drab, muddy plain.

The sky was a steel-grey lid, laden with water-vapour clouds, clamped over this subtly curving sheet of red-brown mud. Here and there, Henry could still make out the overlapping craters which had populated this landscape — some of them had filled up with water, so the land was dotted with circular lakes, rippling sluggishly — but many of the crater walls had slumped. It was like standing in the flood plain of some unruly river.

The landscape was all but unrecognizable from the way it had been just a couple of days earlier.

A wind moaned, soft but guttural. And he thought he could hear thunder, somewhere around the curve of the world — maybe halfway round the planet, he thought; this was still a small world.

Geena was working her way around the Lunar Rover. It was a sorry sight: half tipped up into a flooded crater, its aluminum surfaces streaked with mud, its wire-mesh wheels sunk deep into the soggy surface. The big umbrella-shaped S-band antenna had slumped to the dirt, under the weight of the water which had pounded into it.

Geena got hold of the control column and tried to lift the Rover out of the mud.

“It wouldn’t work now even if you dug it out,” Henry said. “Those wheels—”

“I know.” She peaked a hand over her eyes and looked east, towards the old Apollo site. “We ought to go over there,” she said. “I bet the rain has made a hell of a mess.”

“I bet.”

“The flag, for instance—”

He bent down and was pulling off his boots.

She said, “And what the hell are you doing now?”

“What does it look like?”

“Are you crazy?”

“No.” He placed one bare foot into the mud, then another. He wriggled his toes, and felt the mud ooze between his toes. “Feels like river bottom mud. When I used to go fishing with my brother as a kid—”

“Spare me the cornball reminiscences.”

He eyed her. “Back off, Geena. I’m in no danger. What do you think is going to happen to me? I’ll step on a stinging nettle? The Moon might be wet, but it’s still dead.”

“Except for the Moonseed.”

“Except for the Moonseed, and that doesn’t count right now…”

The light changed, subtly; it became a little brighter, and for the first time Henry made out shadows, around the steeper of the muddy mounds.

Geena was looking up at the sky. “Wow.”

He turned and looked. The clouds had parted: through shreds of cumulus, Henry made out a lacing of higher, streaming cirrus, and there was the Earth, a thin crescent, huge and pale — and there, directly above, was a patch of blue sky.

Blue sky, on the Moon.

Well, of course it’s blue, he thought. The Moon gets the same strength sunlight as Earth. The light is scattered by the same sized particles as on Earth…

“All we need is a rainbow,” Geena said.

“Yeah.”

On impulse, he lifted his facemask. His ears popped, as his oxygen rushed out; he took a single, deep sniff of the air.

Geena rushed up to him. “Are you crazy?”

He dropped his mask back into place. “Probably.” He took deep breaths. “But I’m okay.”

“What did you do that for?”

“I wanted to smell it. To smell the Moon.”

“And?”

He stared around, at the subsiding mud. “Wood smoke,” he said. “It smelled of wood smoke.”

The regolith was oxidizing, even as comet water soaked into it. All around him, all over its surface, the Moon was slowly burning.

They walked further, across the blank, muddy plain.

Henry looked at the empty sky, which was closing over once more. “How long do you figure before they come to get us?”

“It depends how long it takes to assemble another mission,” she said. “At least a month, I’d think; we used up both the prototype Shoemaker landers. They’d have to build more, and—”

He shook his head. “You’re not thinking. Those landers won’t work any more. The air, remember? You don’t need to bring rocket fuel for the descent; you could just glide down. There are going to be strong winds for a while, though. And we’ll need a new design, a way to get back off the surface through this thick air…”

She nodded. “Months, then.”

“At least. Still, resupply will be easy. They can drop stuff by aerobrake and parachute. I don’t think they will let us starve.”

“Or X-38s,” she said. “Space Station escape gliders.”

“Yeah…”

He looked at her sideways. It was hard to read her behind her mask. She still seemed brittle, to him.

Fear and grief, he thought, the loss of Arkady, the pummelling of the terraforming. But it barely showed, at her surface.

Maybe she was in shock. Or maybe it just showed how little he knew her, he thought gloomily.

“We’ll get through this, you know,” he told her.

“I know. But I’d rather be home.”

“Umm.” He thought that over. “Where is home now, for you? Houston? Or—”

“Russia,” she said firmly. “With Arkady’s family. They always made me welcome.”

“Shows where we went wrong, huh.”

“Frankly, yes.”

“I’m sorry. About Arkady.”

She nodded. “I know. But it was unavoidable.”

“Yes,” he said. “Yes, I think it was. But I can see you loved him.”

After a time, she said, “What about you? Scotland?”

He shrugged. “Hell, no. Scotland is Olympus Mons now. Nobody will be going back there… I need to find Jane, and her kid, and we’ll find some place that will last a little longer than Britain.”

“I wish you well,” she said seriously. “I wish you happiness.”

“Thanks.”

“I mean it.”

“I know you do,” he said. “What about Rocky?”

“My mother still has him.” She added, “Much you care.” But he could tell it was a reflex jab.

He looked around. “Maybe one day this will be home, for somebody. That’s the idea, anyhow.”

“You think they’ll let us come back?”

“No,” he said sadly.

“Why not?”

“Because we’ll be too old to breed,” he said bluntly. “Our time is gone, Geena. Gone with Earth. It’s up to the children now… Hats.”

“What?”

“Hats. When the sun breaks through, we’ll fry. No ozone layer up there, remember. And I don’t suppose you packed any sun-cream. Maybe we can take the S-band antenna off the Rover, use it as a parasol.”

“You have a strange sense of priority, Henry.”

“I have a strange mind.”

“What else?”

“It wouldn’t hurt to find a source of water.” He dug a bare toe into the ground; the little pit he excavated slumped back immediately, like wet sand. “The rain is just going to soak away into this stuff. We ought to find the basin of a young crater. Maybe Aristarchus. The regolith is only a few inches thick there, and we should find liquid water pooling. Then we have to keep moving.”

“Moving? Where?”

“East, of course. We ought to go east.”

“Why?”

“Because night will come.” He looked at the sky, seeking the sun. “It isn’t lunar noon yet; we have some time. But the terminator, the line between night and day, moves across the landscape at around ten miles an hour. We can’t outrun it. We have to give ourselves as much time as we can, hope they get the resupply to us before night falls—”

“And what happens then?”

He looked at her, his eyes narrow over his mask. “Figure it out. No sunlight for fourteen days.”

“Oh. The mud is going to freeze—”

“Geena, depending on the atmospheric dynamics, the air is probably going to freeze. For two weeks the Moon will be like it used to be, and we’re going to have to find some way to live through it.” He shrugged. “Or maybe we should just hole up inside our lava tube. We’ll have to think about it. As long as it doesn’t collapse, or flood. I sure don’t want to be caught out in the open when the sun goes down. There will be a wind from hell, all that air sweeping around from the hot side to the cold—”

“But the air will boil off after dawn.”

“Most of it. Some of it is going to collect back where it came from, the cold traps at the Poles. And it will stay there. Nothing has changed the basic geometry of the Moon, Geena. Eventually all this lovely air will finish up back where it started, back at the Poles… Somebody is going to have to figure out a way to stop that, some day.

“But that won’t be for a while. For now, the comet debris is still boiling off, powered by the Moonseed… I figure things won’t start to stabilize until all the ice has boiled off. Which will take a year, at least.” He squinted at the Earth. “Maybe they will send the first biogens. There’s no reason to delay. Photosynthetic plants, algae maybe, to start the job of turning all this sunlight and carbon dioxide to oxygen and food.”

“Henry, how long is all this—” she waved a hand “—going to last?”

“Well, even if we keep it from freezing at the Poles, long-term the atmosphere is going to leak away into space. But it’s a slow process. It’s like putting a bucket of water in the desert. Sure, the water evaporates, but it takes a long time because it can only get out through the comparatively small surface area of the top. In the same way the upper rim of the atmosphere will only allow the air to leak out slowly…”

She pulled at her mask, adjusting it. “Always the scientist. You tell me everything except what I want to know. How long is long term, Henry?”

He shrugged. “Maybe ten thousand years.”

She said gently, “Time enough to think of something else, then.”

“I guess so. Come on. Let’s go pack.”

Side by side, arguing, planning, they walked back towards the lava tube.

2

A year later…

She was in hospital when Henry returned from the Moon.

She hadn’t wanted it this way, but the tests had become overwhelming: the best American technology, X-rays and scans and ultrasound and blood tests, and a whole set of -scopies which left her bewildered, sore and humiliated: sigmoidoscopy, colonoscopy, gastroscopy, bronchoscopy, cystoscopy.

“I didn’t know I had so many orifices,” she told Henry.

“Oh, Christ, Jane,” he said, and he sat on the edge of her bed.

After a year on the Moon his gait and movements were clumsy, as if he expected everything around him to happen in slo-mo. She could see where the rigours of reentry to Earth’s atmosphere had left him bruised, around the neck and eyes.

And every pore, every fold in his skin, was etched with deep-ingrained Moon dust.

Still, it was Henry, more dear to her than she had anticipated — and more distressed than she had, somehow, imagined, when she had played through this scene in her head.

“It isn’t so bad,” she said. “Leukaemia. I’m only here for tests; I’ll be out of here soon. I might live for years.”

“But not forever,” he said.

“No. Not forever.”

“It ain’t fair.”

He was trying to handle this, she realized, and she needed to give him time. She’d had more than a year to get used to the idea.

He said, “You never even told me.”

“The NASA psychologists wouldn’t let me. They were worried about your morale, up there on the Moon.”

“Pointy-headed assholes,” he murmured. He took her hand. “But it ain’t fair, whether you told me or not. I did it for you.”

“Did what?”

He shrugged. “Blew up the Moon. Saved mankind. Whatever it was I did it for you, for us. To give us a future.”

“Maybe the NASA shrinks were right, then.”

They fell silent, and started to avoid each other’s eyes.

After all, what were you supposed to say? How’s your cancer? How was life on the Moon?

She dug out a letter from the stack on her bedside table. “I got this from someone called Garry Beus.”

“Beus?”

“Son of Monica Beus? The physicist lady you knew?”

He nodded stiffly.

She said, “She learned about me, through my connection to you, before she died, and told Garry.” She glanced over the letter. “So he wrote to me. Kind thought. He’s in the Air Force here. He’s applying for the astronaut corps, the new Earth-Moon ferry pilot positions they are opening up… He says Monica left a memory box for him. Actually for his children, her grandchildren. Do you think I should do that for Jack?”

But he didn’t reply. When she looked up at him again he was crying, the tears spilling down his cheeks, pooling Moon dust in the lines under his eyes.

3

Ten years later…

Coming inland from the sea, driving north-east from Cape Town on the N1 highway, it took Henry and Jane two hours to drive through the coastal mountains to reach the Karroo itself.

The ride, through mountain passes and the contorted passages through vales of rock, was spectacular. But then the landscape flattened to a desert, populated by what the old Afrikaners called fynbos, a mixed, complex flora of shrubs and bushes. It was spring, here in the southern hemisphere, and the desert — sheltered by its encircling mountains from the acid rain and climate shifts suffered by most of the world’s land masses — was putting on a show, red white and yellow flowers of every shape.

At last, though, even the fynbos submitted to the logic of the climate, and only aloe and cacti relieved the panorama of rocks and sky.

At a village called Touws River — abandoned now — they came upon the first Karroo rocks: squat black mudstones, sitting atop the younger Cape sands. Henry knew that the mudstones had been dumped from icebergs, floating on the surface of the polar ocean that had once covered this land, an ocean four hundred million years gone.

Jane stared out the window, with that mix of patience and intelligent interest that had always characterized her, and the low, smoky sun picked out her old melanoma scars.

Ten years. And still, every day they were granted seemed like a bonus to him, a new gift.

Henry drove on, and the rock grew more complex.

In a lifetime of geology Henry had never been here before, to this high-veldt plateau that covered two-thirds of South Africa. It was a large, empty place, devoid of human history, unpopulated save for a few scattered towns and farms — most of them abandoned now — crossed only by the immense road between Cape Town and Johannesburg. But to geologists and palaeontologists this land of sandstones and shales, piled up into the tablelands the Afrikaners called koppies, was one of the Earth’s greatest storehouses: a thousand-mile slab of sedimentary rock that was the best record on Earth of land-animal evolution.

The Karroo had always been, for Henry, a place for the future, to visit before he got too old, or died. Now he was forty-five, though he felt a lot older, but the future was self-evidently running out.

So here he was, before it was too late.

They stopped near a large koppie, and clambered stiffly out of the car. It was still morning, and the air was blessedly cool; Henry found himself surrounded by cactus and aloe and wild flowers.

Henry and Jane didn’t speak; their routine, working together, was long enough established by now.

Henry shucked off his antique Air Jordan trainers and pulled on his heavy field boots. He smeared sunblock on the exposed flesh of his arms, legs and face. He donned his broad-brimmed hat, pulled on his oxy-resp and dust and humidity filters — his spacesuit, as he thought of it — and he attached his digital Kodak to his chest bracket.

He buckled on the old leather of his field gear and picked up his hammer and chisel, all of it worn smooth by hundreds of days of sun and rain.

The familiar ritual, which for Henry long predated the coming of the Moonseed, was a great comfort to him. It was a prelude to the greatest pleasure of his working life, which was field work. The nature and objectives of the work had changed, but the pleasure he took in it hadn’t.

Jane knew him well enough now to let him be, to relish this moment.

So he walked into the desert, looking for fossils.

The ground was full of so much detail it would be easy to miss the fossils; the trick was to train the eye and brain to filter out the noise and pick out the key signs. But right now, he didn’t know what those signs would be. Bones, of course, but would they be white or black? Crushed or whole? In the sandstone, river bed deposits, or the shale, silt and mud deposited by ancient floods, now metamorphosed to rock?

It took a half-hour before he began to see them: fragments of bone, protruding from the rock. He recorded their location with the Kodak; the camera was tied into the GPS satellites so the location and context of the specimens were stamped on their images. He scooped up the fragments, unceremoniously, and stuffed them in a sample bag.

As the day wore on, and his eye grew practised, he found more impressive samples. Bones of ancient amphibians, two hundred and fifty million years dead. The tiny skeletons of two burrowing proto-mammals, his earliest ancestors, white and delicate, embedded in a dark silty matrix. Here, peering ghoulishly out of a layer of flat sediment, was the skull of a dicynodont, a low-slung, pig-like animal a couple of feet long, covered with fur and sprouting impressive tusks.

He tried to imagine what it must have been like here, a quarter of a billion years ago.

But right now there was no time to study, classify, identify, deduce. For now, all Henry could do was to collect the raw data.

Geology and palaeontology had always been a race against the predations of weathering and human expansion.

As Earth’s upper layers wore away, ancient bones were exposed, removed from their quarter-billion-year storage, and, in a relative flash, eroded or frost-cracked to dust. Humans could only hope to collect a handful of these ancient treasures before they evaporated like dew.

Now, of course, that time pressure had gotten a lot worse.

He came at last to a new layer of rock, a coarse brown sandstone which overlay the black shales below.

The upper bed was almost devoid of fossils.

This layer marked the boundary between the Palaeozoic and Mesozoic eras, a boundary in time marked by the greatest extinction of life in Earth’s history. The ancient spasm of death, recorded in rock, had been obvious to the first modern geologists, the gentlemen-scientists from Edinburgh.

Even now, nobody knew how it had happened. The more famous extinction pulse at the end of the Cretaceous, the one that had killed off the dinosaurs, had attracted a great deal more study, but that event had involved far fewer species. The best explanation was a slow deterioration of the climate, accompanied by a lowering of sea level, that had created conditions inimical to most life existing at the time.

That was plausible. But nobody knew.

The answer was surely embedded in these rocky layers somewhere, in the bones and skulls eroding out of the Karroo. But Henry could grab all the samples he liked; he was sure the answer would never, now, be found.

Henry had grown up believing that the future was, more or less, infinite, and that there would be time — for generations to come, if not for him — to figure out answers to most of the great questions. Earth itself held the clues to the great puzzles of geology and palaeontology, and Earth would always be there…

But the future wasn’t infinite any more, and Earth wasn’t going to last forever.

There just wasn’t time for the slow processes of science to unpick the secrets of Earth’s past. When the evidence was gone, it would be gone forever, and they would never know.

So, here was Henry clambering over the Karroo, grab-bagging bones out of the ground.

Field work was now the only game in town, in all the sciences.

Nobody was doing analytical science any more. The only people working in labs were directing the others, out in the field.

Most of the effort, in fact, was in biology. In what was left of the rain forests, half-trained researchers were wrapping entire giant trees in plastic and drenching them with bug spray, hoovering up the stiff little bodies into nitrogen-cooled collection flasks, for eventual shipping to the great Arks that were flying to the Moon.

The National Institutes of Health’s Natural Products Repository in Maryland — fifty thousand samples of plant, microbial and marine material from thirty tropical countries, stored in forty-one walk-in freezers — had been compactified, roughly catalogued and fired off to a cryogenic store in some deep-shadowed crater on the Moon. Some of the big bioprospecting drug companies, like Merck which had spent years trawling the flora and fauna of Costa Rica for resources for new products, had had similar repositories impounded and shipped off-Earth, though not without bloody battles over compensation.

And so on.

No time to classify, even to count the species, even those living; of Earth’s estimated thirty million species of plant and animal and insect, only a million had been identified and named by all the generations of biologists that had ever worked. Last chance to see.

There were problems, of course.

There was a lot of vertebrate bias, for instance, in the strategies for rescue. The big mammals and pretty birds were always top of the list, followed by other vertebrates, reptiles, amphibians, fish — even though many of the reptiles, for instance, were already literally drowning in the moisture-laden air that had followed the final melting of the ice caps, and the evaporation of so much ocean water.

And nobody could agree on the corner cases. Biodiversity or not, was it right to preserve the last samples of anthrax, or the Ebola virus, or the last tsetse flies?

And there were the bad guys. Like the cartel who had hunted down and wiped out the last elephants — before the geneticists managed to collect embryos for cryostorage — in order to get an all-time monopoly on ivory. Not to mention the reports, many substantiated, of crazies who were deliberately spreading the Moonseed, accelerating its propagation…

There were lots of reasons to do this, to evacuate the biosphere.

The new Moon needed to be colonized, of course, by the right creatures to coexist with mankind, to flesh out a new biosphere. And looking further ahead, a lot of people muttered vaguely about biodiversity. Nobody knew what benefits might be waiting to be discovered: new foods, better medicines, waiting to be derived from plants and animals yet to be catalogued.

And then there was the potential of species, far beyond their economic value to humans. It would have been hard to extrapolate the rise of mankind from the tree-dwelling mammals that hid from the dinosaurs seventy-five million years ago. Who could say what great societies might arise from the beetles and reptiles and birds, if they were only given the chance?

But for Henry there was a deeper sense of ethics involved.

Homo sapiens was one of the newest species on Earth. Maybe it was homo sap’s fault that this calamity had been visited on the planet; maybe it wasn’t. At any rate, wasn’t there an obligation on the species that commanded most of the planet’s primary production to save as many of the other, older species as it could?

But in the end, maybe it was going to make little difference. For there just wasn’t enough time.

Upcoming was the greatest extinction pulse of all, dwarfing even the end-Palaeozoic. This time there would be no recovery, no slow million-year clambering back to diversity, no reconquest of abandoned ecological niches. Now, evolution on Earth was at an end; now, whatever wasn’t sampled or collected was lost forever.

Even the rocks were going to die, this time. So here were Henry and his wife, running through the desert and grabbing the rocks and bones, for all the world like the Apollo astronauts during their three brief, precious days on the Moon… Apollo.

Suddenly, as seemed to happen too often these days, he was hit by a jolt of nostalgia. Apollo 11: Moonwalk parties, under clear starry skies, when Henry was eight or nine or ten. God, it seemed a million years ago, a world that was ten degrees cooler, or more, where there were still ice caps, and the new inland sea hadn’t covered over the state of Henry’s birth…

Jane tired first. The cancers and their treatment had left her weakened. She returned to the cool of the car and turned on the radio. Henry could hear the voices of news announcers.

The human world continued to turn. Less news than a decade ago, because less people. The volcanoes and the quakes and the floods and famine and war had killed off all but — the estimates went — around a billion people. Now, numbers were still declining, but more slowly. Almost gracefully.

Less news. Nuclear war in the Balkans. Mutant riots in Asia. There was something about the war crimes trial of Dave Holland, the former British Prime Minister, who, he vaguely recalled, Henry had once met. The trial had finished with Holland being convicted of genocide during that desperate last-ditch British invasion of southern Ireland, mounted from Ulster, Prime Minister Bhide apologizing to the world, a death sentence ordered…

But the murmur of words, emanating in digitized perfection from some satellite, meant little to Henry beside the dusty reality of these ancient rocks.

Henry laboured on as the sun climbed higher in the sky. The sun was surrounded by a Bishop’s Ring, fat and oppressive, volcano ash.

That night they ate their simple meal, and huddled together in zipped-up sleeping bags, and waited for the Moon to rise.

Here it came, fat and full and cloudy, banishing the stars. And as they watched, a fine, white streak flashed across the Moon’s fat equator, a meteor scratch that wrapped itself half the way around the twin planet.

Jane, her head cradled in Henry’s arm, stirred, half-asleep. “Do you think that was Jack?”

“Perhaps.” Or someone else’s child, he thought, falling to the Moon in one of the Arks, the huge, heavy, clumsy mass transports, cushioned by the Moon’s new atmosphere behind a fat aeroshell.

Henry’s outlandish scheme had worked.

It was no less difficult to get out of Earth’s gravity well than it had ever been. But the presence of a braking atmosphere on the Moon had reduced the fuel load the big Arks had to carry by an order of magnitude, and made mass evacuation, of humans and the biosphere, possible. Not only that, he had given them somewhere worthwhile to go.

And so the Shuttle-Zs launched almost daily, from Canaveral and Kourou and Baikonur, crude Saturn V-class boosters assembled from Space Shuttle technology, people crammed into sardine-can spaceships, fleeing to the Moon. He knew that Geena had emerged from her voluntary exile in the Russian heartland to work at Baikonur, trying to maintain some kind of standard of excellence among the fragmented, ill-trained and badly frightened work force there.

Or maybe it was a Chinese ship, or one of the Indian fleet, based on old Soviet-era Energia technology, built with such haste and crammed even more full than the Shuttle-Zs, with even less precaution and safety checks than in the western sites. The Indian failure rate was a whopping forty per cent, and the toll in lost lives, on those crowded space trucks, was immense. Frank Turtle, the strange little guy from the bowels of NASA who had done so much to return humans to the Moon, had lost his life when one of those big old Energia clones had dropped back to the launch pad on Sri Lanka and blown apart, taking half the island with it.

The rumours were that the failure statistics in China weren’t much better.

It wasn’t going to stop the launches, though, nor the desperate press of people to get themselves or their children on those ramshackle ships. And Henry knew that any government that tried to scale down its launch program would suffer massive civil unrest. The launches were a safety valve, he supposed, the promise of one route, at least, out of the trap Earth had become.

There was a lot of bitter conflict among the nations sending people to the Moon — the violation of international agreements on quotas and priorities went on daily — and it looked to Henry as if humanity was just going to transport all its old prejudices and inner conflicts intact to the new world, and presumably beyond. Depressing, but entirely predictable.

The evacuation was gigantic, but it could never be complete.

It would be possible to save only a fraction of the billions of people with which Earth had once teemed. Hence the Bottleneck laws. If the population was reduced to the minimum, by savage birth control measures, then, simply, there would be less people to be abandoned, to die, when the end came.

Most people accepted that. About the only thing humans could control about this catastrophe was their own numbers: the human souls who would be spared a birth that would doom them only to the flame.

Most people, it seemed to Henry, were doing their best, in this changing world. Behaving honourably, remarkably so in the circumstances. Surveys showed most populations around the planet were restricting their child birth rates voluntarily, accepting the Bottleneck laws.

And, it was estimated, millions could be saved, before the final destruction.

Remarkable, he thought. I bootstrapped a world. In the end, perhaps I really did save mankind. A fraction of it, anyhow.

He’d saved Jack, at least: still just twenty-one years old, the boy was healthy as an ox and smart as a tack. Maybe that one achievement was enough, to justify Henry’s life.

Now Jack was going to the Moon. But not us, Henry thought. There is nowhere for us, but here.

Jane stirred again. He kissed the top of her head, the thinning hair there, and she settled deeper into sleep.

As it turned out the Karroo was their last trip together, before Jane entered what the doctors delicately called her terminal stage: when their various treatments served no further purpose, and Henry, geologist turned amateur palaeontologist, became a nurse.

Some of what they had to face was much as he anticipated. The painkillers and their side-effects. Her loss of appetite; he learned to cook Lebanese-style, masses of small, spiced dishes, to tempt her. After she was bed-ridden, there was the need to care for her skin: rubber rings, protective pads for her heels and elbows, and a bed cradle to keep the weight of the covers off her legs.

And there were some things he didn’t anticipate. The constipation that doubled her in pain. The soreness in her mouth, which he treated with lip salves, mouth rinses and flavoured crushed ice for her to suck.

He wanted to move her bed downstairs, in their home in Houston, but she wouldn’t accept that. It would be the mark of the end, she said.

She would die upstairs.

Strange thing. He’d been to the Moon, but he’d never seen anyone die close up.

It wasn’t sudden. She slept more, sometimes drifting into unconsciousness, from which he couldn’t rouse her. Her breathing became noisy, like a rattle, but the doctors said it was just moisture on her chest.

Sometimes, though, when she appeared unconscious she was aware, but unable to speak or see. But her hearing probably still worked — hearing was the last sense she lost — and so he spoke to her, reading her letters from Jack on the Moon, or news items, or, just, talking to her.

Until there came a day when she seemed to fall ever more deeply into sleep, and she simply stopped breathing, and that was all.

And Henry knew that he would be alone, for the rest of his life.

4

And ten years more…

Ten years on, ten years older, and here was Henry putting on his spacesuit, fifty-five years old and utterly alone, letting the e-letter buzz in his earpiece for the fourth time, devouring this communication from the nearest thing to a son he ever had.

Dear Dad…

…I took little Nadezhda out to see the ecopoiesis farms in your old stamping ground of Aristarchus. They tell me they modelled the ecosystems here on the dry valleys of Antarctica, back when there used to be ice caps. Mats of green algae and cyanobacteria, lapping up the sunlight, resistant to the shortage of water and low partial pressure of oxygen, pumping out the oxygen. In some of the more clement areas there are even lichens and mosses, growing out in the open…

The ground here was mud, baked utterly dry, cracked into hexagons the size of dinner plates. No water anywhere, of course. Mud, as far as Henry could see, ocean bottom mud, baked dry and hard as concrete; mud, and sand dunes, and salt flats, and gravel fans, covering this dried-up ocean bed.

…We went to see the Apollo Museum there, at Aristarchus. They put it under a dome and reconstructed a lot of the original landing site, right down to the footprints they repaired from the rain damage they suffered. The day we were there they had Tracy Malone, the daughter of one of the astronauts, unveiling a plaque to her father, along with Geena, your ex-wife, who’s been working on lunar heritage projects now she’s retired. Quite symbolic: a representative of the first wave of lunar travellers, and the second, Geena, surrounded by the likes of us, the third. We introduced ourselves to Geena and she said to say hello. They showed Tracy Malone the place her father wrote her name in the dust with his fingertip. It’s under glass now. She cried a river, and it was a nice moment of closure, but I don’t think anyone had the heart to tell her they had to reconstruct it from the photos…

The sky was just a dome of mud-orange haze. But it wasn’t hard to see his way here, about as bright as an early evening in LA used to be. In fact there was more sunlight than appeared, still enough to sustain agriculture, to feed what was left of the Earth’s population, under the big domes in the old deserts.

Not that there was much left of the Earth’s population, all things considered. And if the stories were true about Siberia — it was said that because of the Venus radiation, and a lot of ancillary shit when the Chernobyl-era reactors out there started to go pop, a new homo species had emerged, viable, unable to interbreed with outsiders — the estimates of surviving human populations might be even further off.

…Nadezhda is going to spend her next break from school working at the Tycho carbon-sequestration pit.

I’ve got mixed feelings about her working there.

With all those burners and flues, Tycho is heavily industrial — something like Pittsburgh used to be, or the Ruhr cities. And with the same darker social side. They burn the biomass to recover volatiles, before burying the carbon-rich residue. It’s all part of the global scheme to maximize the production of free oxygen, which not many of us understand… But Tycho is one of the few places where the work we’re doing is simple enough for a five-year-old kid to contribute to.

I’ve taken Nadezhda around the place I work, the oxygen fountain at Landsberg. It sounds exotic — the ten-thousand-megaton thermonukes, the controlled energy cascades from Moonseed beds, all of it cracking the lunar regolith for oxygen — but there isn’t much, really, to see.

It can be a little bleak here.

For the foreseeable future, humans are going to be consuming eighty per cent of the lunar biosphere’s net primary production. And that’s a hell of a lot, maybe three times as high as humans ever reached on old Earth.

That means all the arable land surface we make, even most of the plankton in the crater lakes, is going to have to be turned over to crops. Other than humans, only those creatures that can survive in fields and orchards can be permitted. Any that need virgin forest or any kind of undisturbed habitat are going to have to stay in the zygote banks for now.

They tell me it’s going to take all of ten thousand years before we’re stable and self-regulating, before a human will be able to take off her resp mask and walk out of the domes… Still, we’re promised the first trees and grasses under the Copernicus dome before the decade is out. They are concentrating for now on developing the most useful crops: food, like potatoes, bananas, yams, sugar-cane, coconut; but also gourds and bamboo and plants we can use to make tapa cloth, dyes and oil.

It’s a grand vision, for all that. When the full terraforming gets started, the ecologists say it is going to be like the colonization of new volcanic islands, like Hawaii. The few species we release here to this native soil will explode into all the niches they find, over time, and diversify, new plants and animals to complete the colonization of the Moon. No doubt producing a new ecosystem the like of which Earth never saw.

But that will take a million years, they say. I wish I could fast-forward to see it. Morning on the Moon…

Henry checked his recording equipment, balky modern stuff which he didn’t know how to work, and thought about Earth.

It was the great tectonic events, of course, which had done the greatest damage. There had been the great lava flows off the east African coast, six thousand square miles of new basalt spilling in waves across the land, spewing out gases; everyone thought that was a stupendous catastrophe.

But the coup de grâce had been the giant magma plume that had burst, unexpectedly and explosively, through the crust beneath Yellowstone.

It was an explosion that had been ten thousand times as powerful as all mankind’s nuclear weapons, at their peak, ignited together. From a caldera the size of New Hampshire, blazing material had punched out of the atmosphere — some even entering low orbit — most of it falling back as giant fireballs which ignited what was left of the Earth’s vegetation.

And from the crater itself a huge fireball, followed by a dust plume, had swept up to the stratosphere, and added to the soot and dust from the burning forests to create a planet-covering pall of darkness.

Lights out, all over the Earth.

The atmospheric shock-heating was enough to cause oxygen and nitrogen to combine to nitrous oxide, which had combined with rain water to make acid; and enough acid rain had fallen on the planet to make the top three hundred feet of the oceans sufficiently acidic to dissolve calcareous shell material, so driving still more orders of life to final extinction. The food chains, already tenuous, had finally collapsed. Death soaked the planet, starting with the phytoplankton.

Ash falling, all over the Earth, like the thin layer that had been found in the rocks following the Cretaceous extinction, once puzzled over by scientists like Henry in bright, clean labs…

The magma plumes, giant wellings-up in the Earth’s molten substance that originated as deep as the core-mantle boundary, had been significant in Earth’s deep history. They had shattered continents, breaking up the Pangaea supercontinent, splitting Gondwanaland into two halves, splitting India, Madagascar and Antarctica from Africa. But all that had taken hundreds of millions of years. Now, the plumes” violence was manifested on timescales of mere decades, even years.

There was the mountain-building event in Antarctica, for instance, where the Indo-Australian plate had suddenly decided to set off south. More of the great magma plumes under Earth’s hotspots had come boiling through the crust, at the Canaries, under the tsunami-lashed wreckage of Hawaii, under Iceland. And the rift valleys all over the Earth had started to open up, in east Africa and Lake Baikal and the Red Sea, the continents just splitting apart. The river Rhine had disappeared into a crack in the ground, and then the graben through which it once flowed started to bubble with new ocean-floor plate.

What all the volcanism was mostly doing, in addition to killing people and boiling the seas, was pumping out a new atmosphere for the Earth: an unwelcome air of carbon dioxide and sulphur dioxide and hydrogen laced with arsenic and chlorine, that would, the estimates went, finish up ten times as thick as the old nitrogen-oxygen one. Immense greenhouse cycles had already started, and the oceans were evaporating and would soon start to boil…

And Henry’s beloved Earth was turning into what Venus used to be.

One large community of people had retreated to what was left of the oceans, sheltering from the heat there. But even the marine invertebrates were choking on ash. And the volcanism had polluted the water with exotic trace elements — like cadmium and mercury and iridium and osmium — and the oceans, the birthplaces of life on Earth, were, in their last days, becoming toxic.

But, in a way, it was geologist’s heaven. Processes that ought to take millions of years were occurring in mere years, even months. As if the Earth was trying to cram in her best special effects while she still had time. Geology, overwhelmed with unwelcome evidence, was at last becoming a mature science — just as, so he heard, fundamental physics had been galvanized by the study of the Moonseed processes, so that whole new areas of theory and technological achievement were being opened up.

None of it any use, though, in stitching poor Earth back together.

Dear Jane had called the sites of the great magma plumes Earth’s chakras. The energy centres, the wheel of light from which Earth’s energies were bleeding away. It was as good a description as any.

He stepped forward cautiously, keeping an eye on the compass set into his chest pack. The compass was inertial, a little spinning gyroscope system, like they used to use in aircraft and spaceships. It was the only type that was reliable nowadays; the electronic kind that communicated with the GPS satellites was too easily thrown out by the auroras and the big electrical storms that flapped around the planet, and you couldn’t use a magnetic compass, of course, since Earth’s magnetic field had gone to hell. The geophysicists said it was all to do with the melting of the ice caps and the oceans” evaporation, all that mass redistribution making Earth wobble like a kid’s top after a hefty kick. The reversals in the magnetic field’s polarity were coming about once a year now, thus screwing up the magnetosphere and letting through the cosmic rays, just adding to the fun down here, and coincidentally fouling up Henry Meacher’s map-reading…

But he couldn’t make head or tail of this damn astronaut’s compass.

Well, maybe it was a little brighter to his left, to the east, where the sun must be rising. Maybe there were miles of cloud above him, the evaporated oceans lofted into the sky; maybe his green Earth had turned to a pearly white ball like Venus had been, where an American needed a space suit to walk out of the big underground shelters; but as far as he knew the world was still spinning the right way.

Anyhow, he might get lost, but wasn’t going to come to any harm, on this plain of mud.

He stepped forward, carefully.

…It still seems remarkable to me to see Nadezhda bounding around in the low gravity without an ounce of self-consciousness.

Of course she has no memory of the Moon before the modification. It seems perfectly natural to her to lope around the mare with nothing more than cold weather clothing, sunglasses and an oxygen pack! I’ve shown her recordings of the old Apollo Moonwalks, but she doesn’t say much.

I suspect among the young people born here there is already a conspiracy theory circulating: that the Moon has always been this way — that maybe the old airless Moon never existed — that maybe our “terraforming” is a clumsy attempt to rectify some eco screw-up on a previously pristine Moon. God, if only that was true!

I do know that the images the young ones see of Earth are affecting them in ways we didn’t anticipate.

For sure, the kids are evolving away from us, Henry. Already. Oh, Nadezhda doesn’t look much different from me at her age, when I was nagging mum to take me to the McDonald’s on Princes Street; it’s going to take generations even to work through the obvious physiological changes — the low G adaptations, for instance; Nadezhda will have to spend her life on courses of treatment against bone calcium loss and body fluid imbalances.

But her children will be a little taller, and a little more resistant; and her grandchildren a little more so… and so on.

Humans will survive here. I’m sure of that now. What I’m not convinced about is how much they will care about old Earth.

The young ones already have their own agenda. It’s hard for them to have any loyalty for the home planet when they see that now you need spacesuits just to survive down there…

There has already been some trouble at the drop points in Procellarum. Resistance to new immigrants, even to accepting more loads of rocks and frozen bugs from Earth.

I just hope it all holds together long enough to get the best of it away, before the end.

Well, maybe it’s inevitable. We’ve done all we can to equip the kids and educate them. Now, the future is theirs…

As the tectonic events accelerated, predictions were being revised, and it seemed they were approaching the Bottleneck itself, the great, final die-back from which nothing on the surface of Earth, nothing, was going to escape. The laws had gotten harsher. No more children to be born on Earth. Anybody who refused to comply would be refused boarding, for themselves or their children, to the Arks to the Moon.

It was harsh, and not universally accepted by the governments, and had caused revolution, and more than one war. In South America, where the Pope had mounted his last stand against the managed decline of the population, the fallout of thermonuclear destruction had added to Earth’s final woes.

And nevertheless — despite the logic and wisdom, despite the inevitability of the Bottleneck — there were still children being born on the Earth: the animal response of frightened humans to the threat of death, life trying to propagate in the face of hopelessness. But the helpless new kids were only more moths to the flames, Henry thought.

In a way, he was glad Jane wasn’t here to see this.

At least she had lived to see her grandchildren, growing straight and tall in the thin, clean air of the Moon.

But as for Henry, this was his home.

He had been in love with the Earth since the first time he opened a geology book, the first time he picked up a pebble from a beach and wondered how it got there. Now it was burning down around him, but he wasn’t about to abandon it.

He found himself walking on a layer of salt, white and bright in the smoggy twilight, that crunched under his feet.

This ocean had dried once before, though not in human history. And that had been significant. The ocean had ceased to buffer the local climate, feeding land areas with rainfall and reducing temperature swings. Forests had disappeared, to be replaced by dry grasslands, and the arboreal creatures had faced the choice of migrating, adapting, or dying.

One group of tree-dwelling primates was forced out of the branches that had hidden them from predators, and pushed onto the new grasslands of Africa, where they were going to need greater size and better locomotion and, above all, to get smarter.

They had never looked back.

Now, five million years later, a descendant of those frightened primates, dressed in a fragile spacesuit, stalked across the dried-up bed of the Mediterranean, looking for fossils and human artifacts, a few last treasures for the final Arks to the Moon.

5

And a final ten years…

Henry was standing on the Earth’s oldest rocks, and talking to his granddaughter, on the Moon.

…So here I am, Nadezhda, your honorary grandfather, sixty-five years old and no smarter than I ever was, waiting for the other shoe to fall.

I don’t suppose you know what that means. I can’t even remember how long it takes a shoe to fall on the Moon. Or if you wear shoes in those domes of yours.

Whatever.

I have instruments here, various sensors that show me what is happening inside the planet. I have a whole-Earth image here broadcast from one of your nearside observatories, I think at Kepler. I’m glad you can see the surface, from up there. The giant volcanoes blew off the crud, the Venusian atmosphere that was gathering, and who’d have thought that would be a blessing?…

He was in Isua, in west Greenland. He was standing on supracrustal rock bounded on both sides by granitoid gneisses: three point six billion years old. Babies for the Moon, but these rocks were the old men of Earth, the oldest, most stable place on the planet.

It seemed appropriate, to be here, now.

He was in a concrete, heat-insulated, pressurized bunker, which in turn was protected by what he would have called a force field when he was growing up, a piece of the smart stuff the kids on the Moon had been dreaming up. Technological evolution, force-fed by its environment, filling the niches.

He was here because it was one of the few solid, stable places left on the planet.

Earth, from space, looked like a jigsaw puzzle, or maybe like a pan coming to the boil, black continent pieces outlined by blood red.

It was astonishing how events had accelerated, towards the end. It had been faster than anyone had believed.

He wondered how long he’d last. How much of it he would see.

…Did you know I was alive when Apollo 8 flew by the Moon? The astronauts, Borman, Lovell and Anders, were the first humans to see the Earth whole. They thought it was blue, and fragile, like a Christmas tree ornament. Well, they were right. Fragile.

I know you think I’m crazy to stay.

You know, one of the most beautiful theories of the history of the Earth was published by a guy called the Reverend Thomas Burnet, in England in the seventeenth century. Burnet said the Earth originated from chaos, a fluid mass of particles of matter. The particles grew together to form a perfect sphere with a smooth surface, concentric shells of liquid and air around a solid core. But there was an oily fluid in with the water, and when dust mixed with it, it formed a firm and fertile envelope over the layer of oily water.

But the sun’s heat made the fertile shell dry and crack. The waters below boiled, vaporized and exploded, and the Earth was flooded. When the agitation settled out, the waters drained back to the low places. Fragments of Paradise were left sticking up as continents and islands.

And that’s the world I was born on.

Eventually, though, flames would come to purify the Earth, and it would return to its paradisical state, and finally merge with God by becoming a star.

Well, it was a theory. That’s the way geology used to be, kid, a thing of dreams and fancies unsullied by brute fact. We only got into all that science stuff when the industrialists came along and started asking where they were going to find coal and iron ore and oil, and why the hell is the world so complicated anyhow?

We know the answers now, of course: all those aeons of mountain building and destruction, the rise and fall of the seas, the compaction, pressure, heating, cooling, sedimentation, erosion. The Earth is a rocky labyrinth.

Was, anyhow. It’s getting kind of simpler, even as I stand here.

Strange how Burnet seems to have been right all along, though, doesn’t it?

It had been a couple of years since the Moonseed made the mantle so hot that plate tectonics effectively stopped. The plates were too hot to behave in the rigid way they used to; and the rock of the mantle was just too runny to support big horizontal movements.

It had been thought that would reduce the volcanism for a time, but it didn’t turn out that way.

Still, the map of Earth was recognizable. Just.

The ocean plates were softening and melting back. The continents showed up in his images as black and dark islands in glowing oceans, the ancient granite cratons surrounded by crumpled greenstone. The cratons were the cores around which the continents had accreted in the first place, crust slabs which had formed in the centre of ancient mantle convection cells; now they were being uncovered once more.

It was as if, Henry thought, someone was winding back Earth’s evolution.

And there were giant mantle plumes breaking out all over the planet, flood lavas, volcanic domes, cones and even coronae — features never seen on Earth before, only on lost Venus, basaltic domes surrounded by annuli of ridges and grooves. Nowhere was left untouched in the catastrophic resurfacing of the planet.

Hardly anything of the works of humanity survived.

There was one consolation, though. For a time, Earth was the youngest place in the Solar System.

…I want to tell you how much I admire you people up there. My God, you guys think big. Your schemes to bring in comets to graze the Moon’s atmosphere and increase the volatile content. Rebuilding the crater walls and lunar mountains that are already getting eroded by the rain. No plate tectonics on the Moon, to maintain the carbon and oxygen cycles: so you’ll bake the silicate rocks into glass, drive out the carbon dioxide that’s weathered there, and reverse the erosion… Jesus.

I’m not sure if I agree with your projections that you can reduce the time to true terraforming to a thousand years, but I haven’t had the time to run the math. I don’t think you ought to concern yourself with the objections of the Siberians who have colonized farside. They aren’t even human; let them build their own damn world.

But you talk about using the extremal black holes from the Earth’s debris to tip the Moon, to give it seasons, then to spin it up. It’s a nice idea. A final gift from the Earth, to its daughter…

But, Nadezhda, I have to counsel caution. Are you guys sure you know what you’re doing? You’re going to have sixty-feet tides in those new lunar oceans of yours —

Shit.

Sorry. That was a surface wave, a big one. I think it will be over soon…

The continental cores, the ancient cratons, had resisted the magma plumes for billions of years, and, like knots in wood, were tough to crack. But they were not indestructible.

Even as he watched he could see the last of the African plate — cracking and dissolving like scum — there it went…

Africa had been the oldest continent, most of it formed more than two and a half billion years earlier, surviving for geological ages as the hard, protected core of Pangaea, the world continent. Now it was gone, just a puddle of magma.

Goodbye, Africa. Birth place of man. My God.

And now, where Africa used to be, another huge magma plume was starting. It looked like a solar flare. A fountain of rock blasting straight up, uncurling with perceptible speed…

No, not a fountain. More like a fist, punching out of a sack. A mass the size of a small moon, thrusting out of the Earth.

Henry couldn’t begin to compute the energy behind events like that.

The end must be close now.

Already there had to be significant mixing between the core and the mantle layers. The planet as a whole used to spin at a different speed from its core… Now the whole globe was coupled, structurally. It must be tearing itself apart, like an unregulated motor.

Another pressure wave swept beneath his bunker, cracking the floor. Maybe that was the aftershock of the Africa plume.

He kept to his feet, though.

Now another plate was gone, after five billion years just crumbling away like sugar in water. He thought that was Indo-Australia — the planet was such a mess now it was hard to be sure — and the other plates were starting to slide and crack.

…I know you think I’m crazy to have stayed. I know your new generation of Arks, skimming down from the Moon, had the capacity to take off almost everybody who was left. I know you think I’m like the crazy old fucker who wouldn’t get out of his house when they want to build the highway through it.

Sorry. I guess you don’t know what I’m talking about.

I just didn’t want to leave, is the top and bottom of it. This is my home: here, on the shitty side of the Bottleneck. On the other side is the future, all of the universe, waiting for you.

What would I do on the Moon, except bitch about the processed algae and yack about the old days?

This is my home.

Listen to me. Don’t tip the Moon. Harness the black hole wind. Use it for what it was meant for.

Get out of here, go to the stars.

Godspeed to all of you.

There was more bare magma ocean than continent left now. Giant plumes, everywhere, more of those fists punching out to space—

And here came another shock wave, slamming into the bunker.

An instant of confusion, pain, extreme noise.

He was on his back.

The force field had held. But the whole bunker was over on its side, the floor and walls cracked, shattered to powder.

It felt as if he had bust a leg, a couple of ribs. He couldn’t move. He couldn’t hear anything.

He didn’t suppose it mattered. He was lucky to have survived so long.

The force field was tough. Maybe it would come sailing out of the final destruction event with his old bones preserved inside, battered and crushed.

One monitor was still working, by some miracle. He could still see the Earth.

The planet was a ball of red-brown light, an ocean of magma, barely differentiated, just a few scraps of continent, patches of black slag. But now there were spreading pools of white light at the rims of the magmatic convection cells: plasma, presumably, from the high-energy stuff going on in the interior.

Just like Burnet said. This is the fire. And soon we will merge with God.

The planet looked lopsided. Here came the biggest plume yet, poking out of the equator, where the Pacific plate used to be.

The limb of the planet was… lumpy. Jets of rock vapour pushing out of the lumps, into space. Some of the lumps were falling back, creating craters hundreds of miles across, spectacular impact basins that weren’t going to last more than minutes. And now, a new upswelling—

Shit. You can’t call that a plume. The core must be splitting.

Oh. I’m rising. Like an elevator. The continent must have split. Jane, I think —

6

Earth was once more a ball of magma, everywhere molten, reduced to a primordial smoothness, as it had been when young.

But the planet was expanding.

The unified-force energy released in its core and mantle was overcoming the controlling pull of its gravity. But the expansion was uneven, and bolides, giant chunks of rock, burst out of the churning surface and traced long, glowing curves around the world.

New cracks appeared in the magma ocean, wide fissures filling up with rivers of plasma light, white and yellow and green. As if emerging from a rocky egg, the plasma ball broke open the last shells of Earth, the remnants of the mantle and asthenosphere, molten rock and iron, and hurled out giant globules of spinning, cooling fragments.

The Earth became briefly flattened, its rotation driving its fluid form outwards.

Then the cloud expanded, suddenly, an eruption of light and fire, the energy embedded in its own substance being exploited to destroy it in a silent concussion.

Thus it ended, in a moment of unimaginable violence.

The debris formed a cloud, through which the plasma glow, fading, cast thousand-mile shadows.

Shallow gravitational waves crossed the Solar System, subtly perturbing the orbits of the planets.

Then, placidly, the remaining children of the sun resumed their antique paths, barely affected by the loss of their sibling.

Earth’s closest companion was more disturbed.

At the loss of the tides from its lost parent, the Moon shuddered. Water sloshed in its crater lakes, in giant circular ripples. Ancient faults gaped, for the first time in a billion years, and dusty lava flowed, as if the satellite was aping its parent’s demise.

Some humans died.

But it didn’t last long. And the inhabitants were prepared.

Then the orphan Moon sailed on, alone, cradling its precious cargo of humanity.

And, at the site of Earth, when the cloud of dust and volatiles and planetesimals dispersed, something new was revealed: a tear in space, a jewel of exotic particles, a wind of massless black holes fleeing at the speed of light.

Cautiously, tentatively, the ships from the Moon crept towards the ruin of Earth.