Phase Space

Open Loops

It began, in fact, with a supernova: thus, from the beginning, it was a causal chain shaped by stupendous violence.

The star was a blue supergiant, twenty times the mass of Earth's sun, fifty thousand times as bright. It had formed a mere million years ago.

Nevertheless there was life here.

It had come drifting on the interstellar winds from older, more stable systems, and taken root on worlds which cautiously skirted the central fire.

But the hydrogen fuel in the star's fusing core was already exhausted.

The core, clogged with helium ash, began to burn that ash itself, helium nuclei fusing to carbon. And the carbon compacted to neon, the neon to oxygen… At last iron nuclei snowed, inert, on the centre of the star.

The core's free-fall implosion took fractions of a second. The star's outer layers were suddenly suspended over an effective vacuum. They collapsed inwards, the infalling layers crashing onto the rigid core remnant, and rebounded violently. The reflected shock wave was hurled out of the centre of the star, dragging away the star's outer layers with it…

For a week, the dying star outshone its Galaxy.

For forty years the expanding shell of matter travelled, preceded by a sleet of electromagnetic radiation: gamma rays, X rays, visible light. A human eye might have seen a brilliant blue-white star grow suddenly tremendously luminous, fifty times as bright as the Moon, as bright as all the other stars in the sky combined.

But Earth did not exist, nor even, yet, the sun. The garish light of the supernova washed, instead, over the thin tendrils of a gas cloud: cold, inert, stable.

And in any event no human telescope could have detected, rushing before the light storm, a single, delicate, spidery silhouette.

A fleeing craft.

Scale: Exp 1

In the confines of Ehricke's airlock Oliver Greenberg put on his gloves and snapped home the connecting rings. Then he lifted his helmet over his head.

The ritual of the suit checklist was oddly comforting. In fact, it was just the old Shuttle EVA routine he'd undergone a half-dozen times, in an orbiter-class airlock just like this.

But the Ehricke was no dinged-up old orbiter, and right now he was far from low Earth orbit.

He felt his heart hammer under his suit's layers.

Mike Weissman, on the hab-module's upper deck, was moni-toring him. 'EVI, you have a go for depress.'

Greenberg turned the depress switch on the control panel. 'Valve to zero.' He heard a distant hiss. 'Let's motor.' He twisted the handle of the outer airlock hatch and pushed.

Oliver Greenberg gazed out into space.

He moved out through the airlock's round hatchway. There was a handrail and two slide wires that ran the length of the curving hull, and Greenberg tethered himself to them. It was a routine he'd practised a hundred times in the sims at Houston, a dozen times in LEO. There was no reason why now should be any different.

No reason, except that the Earth wasn't where it should be.

In LEO, the Earth had been a bright floor beneath him all the time, as bright as a tropical sky. But out here, Earth was all of five million kilometres away, reduced to a blue button the size of a dime three or four arms-lengths away, and Greenberg was suspended in a huge three-hundred-sixty-degree planetarium just studded with stars, stars everywhere…

Everywhere, that is, except for one corner of the sky blocked by a vaguely elliptical shadow, sharp-edged, one rim picked out by the sun.

It was Ra-Shalom: Greenberg's destination.

He was looking along the length of the Ehricke's hab module.

It was a tight cylinder, just ten metres long and seven wide, home to four crew for this year-long jaunt. The outer hull was crammed with equipment, sensors and antennae clustered over powder-white and gold insulating blankets. At the back of the hab module he could see the bulging upper domes of the big cryogenic fuel tanks, and when he turned the other way there was the Earth-return module, an Apollo-sized capsule stuck sideways under the canopy of the big aerobrake.

The whole thing was just a collection of cylinders and boxes and canopies, thrown together as if at random, a ropy piece of shit.

But in a vessel such as this, Americans planned to sail to Mars.

Not Oliver Greenberg, though.

One small step time, he thought.

He pulled himself tentatively along the slide wire and made his way to the PMU station, on the starboard side of the hab module. The Personal Manoeuvring Unit was a big backpack shaped like the back and arms of an armchair, with foldout head- and leg-rests on a tubular frame. Greenberg ran a quick check of the PMU's systems. It was old Shuttle technology, cannibalized from the Manned Manoeuvring Units that had enabled crew to shoot around orbiter cargo bays. But today, it was being put to a use its designers never dreamed of.

He turned around, and backed into the PMU.

'Ehricke, EVI,' he said. 'Suit latches closed.'

'Copy that.'

He pulled the PMU's arms out around him and closed his gloved hands around the hand-controllers on the end of the arms. He unlatched the folded-up body frame. He rested his neck against the big padded rest, and settled his feet against the narrow footpads at the bottom of the frame, so he was braced. Today's EVA was just a test reconnaissance, but a full field expedition to Ra could last all of eight hours; the frame would help him keep his muscle movements down, and so reduce resource wastage.

Greenberg released his tethers. A little spring-loaded gadget gave him a shove in the back, gentle as a mother's encouraging pat, and he floated away from the bulkhead.

… Suddenly he didn't have hold of anything, and he was falling.

Oh, shit, he thought.

He had become an independent spacecraft. The spidery frame of the PMU occulted the dusting of stars around him.

He tested out his propulsion systems.

He grasped his right-hand controller, and pushed it left. There was a soft tone in his helmet as the thruster worked; he saw a faint sparkle of exhaust crystals, to his right. In response to the thrust, he tipped a little to the left. He had four big fuel tanks on his back, and twenty-four small reaction control-system nozzles. In fact he had two systems, a heavy-duty hot gas bipropellant system - kerosene and nitric acid - for the big orbital changes he would have to make to reach Ra, and a cold-gas nitrogen thruster for close control at the surface of the rock.

When he started moving, he just kept on going, until he stopped himself with another blip of his thrusters.

Greenberg tipped himself up so he was facing Ra-Shalom, with the Ehricke behind him.

'Ehricke, I'm preparing to head for Ra.'

'We copy, Oliver.'

He fired his kerosene thruster and felt a small, firm shove in the small of his back. Computer graphics started to scroll across the inside of his face plate, updating burn parameters. He was actually changing orbit here, and he would have to go through a full rendezvous procedure to reach Ra. That was what had gotten him this job, in fact. Greenberg had flown several of the missions which docked a Shuttle orbiter with the old Mir, and then with the Space Station. He had even been chief astronaut, for a while.

Then the VentureStar had outdated his piloting skills, and he was grounded, at age fifty.

NASA was full of younger guys now, preparing for the LMP, the Lunar-Mars Programme that was at the heart of NASA's current strategy, inspired by the evidence the sample-return probes had come up with of life on Mars.

This mission, a year-long jaunt to the near-Earth asteroid Ra-Shalom, was a shakedown test of the technologies that would be needed to get to Mars. Ra provided an intermediate goal, between lunar flights of a few weeks and the full Mars venture that would take years, setting major challenges in terms of life-support loop closure and systems reliability.

But there was also, he was told, good science to be done here.

Not that he gave a shit about that.

He was only here, tinkering with plumbing and goddamn pea plants, because nobody else in the Office had wanted to be distracted from the competition for places on the Mars flights to come.

The angle of the sun was changing, and the slanting light changed Ra from a flat silhouette to a potato-shaped rock in space, fat and solid. Ra's surface was crumpled, split by ravines, punctured by craters of all sizes. There was one big baby that must have been a kilometre across, its walls spreading around the cramped horizon.

The rock was more than three kilometres long, spinning on its axis once every twenty hours. It was as black as coal dust. Ra-Shalom was a C-type asteroid - carbonaceous, fat with light elements, coated by carbon deposits. It had probably formed at the chilly outer rim of the asteroid belt. Ra was like a folded-over chunk of the Moon, its beat-up surface a record of this little body's dismal, violent history.

At a computer prompt, he prepared for his final burn. 'Ready for Terminal Initiation.'

'Copy that, Oliver.'

One last time the kerosene thrusters fired, fat and full. 'Okay, EVI, Ehricke. Coming up to your hundred-metre limit.' 'Copy that.'

He came to a dead stop, a hundred metres from the surface of Ra-Shalom. The asteroid's complex, battered surface was like a wall in front of him. He felt no tug of gravity - Ra's G was less than a thousandth of Earth's - it would take him more than two minutes to fall in to the surface from here, compared to a few seconds on Earth.

He was comfortable. The suit was quiet, warm, safe. He could hear the whir of his backpack's twenty-thousand rpm fan. But he missed the squeaks and pops on the radio which he got used to in LEO as he drifted over UHF stations on the ground.

He blipped his cold-gas thrusters, and drifted forward. This wasn't like coming in for a landing; it was more like walking towards a cliff face, which bulged gently out at him, its coal-like blackness oppressive. He made out more detail, craters overlaid on craters down to the limit of visibility.

He tweaked his trajectory once more, until he was heading for the centre of a big crater, away from any sharp-edged crater walls or boulder fields. Then he just let himself drift in, at a metre a second. If he used the thrusters any more he risked raising dust clouds that wouldn't settle. There were four little landing legs at the corners of his frame; they popped out now, little spear-shaped penetrators designed to dig into the surface and hold him there.

The close horizon receded, and the cliff face turned into a wall that cut off half the universe.

He collided softly with Ra-Shalom.

The landing legs, throwing up dust, dug into the regolith with a grind that carried through the PMU structure. The dust hung about him. Greenberg was stuck here, clinging to the wall inside his PMU frame like a mountaineer to a rock face.

He turned on his helmet lamp. Impact glass glimmered.

Unexpectedly, wonder pricked him. Here was the primordial skin of Ra-Shalom, as old as the solar system, just centimetres before his face. He reached out and pushed his gloved hand into the surface, a monkey paw probing.

The surface was thick with regolith: a fine rock flour, littered with glassy agglutinates, asteroid rock shattered by aeons of bombardment. His fingers went in easily enough for a few centimetres - he could feel the stuff crunching under his pressure, as if he was digging into compacted snow - but then he came up against much more densely packed material, tamped down by the endless impacts.

He closed his fist and pulled out his hand. A cloud of dust came with it, gushing into his face like a hail of meteorites. He looked at the material he'd dug out. There were a few bigger grains here, he saw: it was breccia, bits of rock smashed up in multiple impacts, welded back together by impact glass. There was no gravity to speak of; the smallest movement sent the fragments drifting out of his palm.

His glove, pristine white a moment ago, was already caked black with dust. He knew the blackness came from carbon-rich compounds. There were hydrates too: water, locked up in the rock, just drifting around out here. In fact rocks like Ra were the only significant water deposits between Earth and Mars. It might prove possible to use the rock's resources to close the loops of mass and energy circulating in Ehricke's life support, even on this preliminary jaunt.

Ra could probably even support some kind of colony, off in the future. So it was said.

Greenberg had always preferred to leave the sci-fi stuff to the wackos in the fringe study groups in NASA, and focus on his checklist. Still, it was a nice thought.

He allowed himself a moment to savour this triumph. Maybe he would never get' to Mars. But he was, after all, the first

human to touch the surface of another world since Apollo 17.

He pushed his hand back into the pit he'd dug, ignoring the fresh dust he raised.

The cloud was scattered, thin and dark, across ten light years. It was gas laced with dust grains - three-quarters hydrogen, the rest helium, some trace elements - visible only to any observers as a shadow against the stars.

When the supernova's gale of heavy particles washed over it, the cloud's stability was lost. It began to fall in on itself.

In a ghostly inverse of the inciting supernova explosion, the core of the cloud heated up as material rained in upon it, its rotation speeding up, an increasingly powerful electromagnetic field whipping through the outer debris. The core began to glow, first at infra-red wavelengths, and then in visible light.

It was the first sunlight.

Scale: Exp 2

Oliver Greenberg was bored.

He was actually glad to get the call from Gita Weissman about the balky rock splitter in Shaft Seven, even though the lost time would mean they weren't going to make quota this month.

At least it made a change from the usual CELSS problems, CELSS for closed environment and life-support systems, a term nobody used except him any more. Even after a century, nobody had persuaded a pea plant to grow nice straight roots in micro-gravity, and the loss from the mass loops in the hydroponic tanks continued at a stubborn couple of per cent a month, despite the new generation of supercritical water oxidizers they used to reduce their solid wastes.

It's still about pea plants and plumbing, he thought dismally.

He started clambering into his skinsuit, hauling the heavy fabric over his useless legs.

He took a last glance around the glass-wall displays of his hab module. It shocked him when the displays showed him he was the only one of Ra's two thousand inhabitants on the surface.

Well, hell, it suited him out here, even if it had stranded him in this lonely assignment, monitoring the systems that watched near-Ra space. Most of the inhabitants of Ra had been born up here, and lived their lives encased in the fused-regolith walls of old mine shafts. They didn't know any better.

Greenberg, though, preferred to keep a weather eye on the stars, unchanged since his Iowa boyhood. He even liked seeing Earth swim past on its infrequent close approaches, like a blue liner on a black ocean, approaching and receding. It made him nostalgic. Even if he couldn't go home any more.

Suited up, he shut down the glass-wall displays. The drab green walls of the hab module were revealed, with their equipment racks and antique bathroom and galley equipment and clumsy-looking up-down visual cues. This was just an old Space Station module, dragged out here and stuck to the surface of Ra-Shalom, covered over with a couple of metres of regolith. He was tethered in the rim shadow of Helin Crater, the place he'd landed on that first jaunt in the Ehricke. And that had been all of a hundred years ago, my God.

He pushed his way through the diaphragm lock set in the floor of his hab module. He was at the top of one of Shaft Two, one of the earliest they'd dug out, with those first clumsy drill-blast-muck miners. It was a rough cylinder ten metres across, lined with regolith glass and hung with lamps and tethers; it descended beneath him, branching and curving.

He grabbed hold of a wall spider, told it his destination, and let it haul him on down into the tunnel along its stay wires.

Thus, clinging to his metal companion, he descended into the heart of Ra-Shalom.

His legs dangled uselessly, and so he set his suit to tuck them up to his chest. He was thinking of taking the surgeons' advice, and opting for amputation. What the hell. He was a hundred and fifty years old, give or take; he wasn't going to start complaining.

Anyhow, apart from that, the surgeons were preserving him pretty well. They were treating him to a whole cocktail of growth hormones and DHEA and melatonin treatments and beta-carotene supplements, not to mention telomere therapy and the glop those little nano-machines had painted on the surface of his shrivelled-up brain to keep him sharp.

These guys were good at keeping you alive.

This asteroid was small. A stable population was important, and a heavy investment in training needed a long payback period to be effective. So the birth rate was low, and a lot of research was directed to human longevity.

He understood the logic. But still, he missed the sound of children playing, every now and again. The youngsters here didn't

seem to mind that, which made them a little less than human, in his view. But maybe that was part of the adjustment humans were having to make, as they learned to live off-Earth.

In fact he missed his own kids, his daughters, even though, astonishingly, they were now both old ladies themselves.

The surgeons had even managed to repair some of the cumulative microgravity damage he'd suffered over the years. For instance, his skeletal and cardiac muscles were deeply atrophied. Until they found a way to stabilize it, his bone calcium had continued to wash out in his urine, at a half per cent a month. At last, the surgeons said, the inner spongy bone, the trabeculae, had vanished altogether, without hope of regeneration.

He never had been too conscientious about his time in the treadmills. It had left him a cripple, on Earth.

So, at age eighty, he'd left Earth.

Even then they had been closing down the cans - the early stations starting with Mir and the Space Station, that had relied completely on materials brought up from Earth. In retrospect it just didn't make sense to haul material up from Earth at great expense, when it was already here, just floating around in the sky, in rocks like Ra.

So he'd come back to come out to Ra-Shalom, the place that had made him briefly famous.

He suspected the surgeons liked to have him around, as a control experiment. The youngsters were heavily treated from birth, up here, to enable them to endure a lifetime of microgravity. Not a one of them could land on Earth, of course, or even Mars. But not too many of them showed a desire to do any such thing.

The wall spider, scuttling busily, brought him to the mine face, the terminus of Shaft Seven. It was a black, dusty wall, like a coal face. There was dust everywhere, floating in the air.

There were five or six people here, in their brightly coloured skinsuits, scraping their way around the stalled miner. Their suits were seamless and without folds, to guard against the dust. They were all tall, their limbs spindly as all hell, their skeletal structures pared down as far as they would go.

The miner itself clung to the walls with a dozen fat legs, with the balky rock splitter itself held out on a boom before the face. It was a radial-axial design with a percussive drill, powered by hydraulics, with a drill feed, a radial splitter and a loader. But for now it was inert.

One of the youngsters came up to him. It was Gita Weissman, Mike's granddaughter. She grinned through her translucent face-plate; her skinsuit was what they used to call Day-Glo orange.

'Dust,' she said. 'It's always the dust.'

'Yeah.'

'Grab a pump. We want to get this baby back on line or we'll miss quota again.'

He started to prepare a vacuum-pump tube.

The 'dust' was surface rock flour: half of it invisible to the naked eye, abrasive, and electrostatically sticky. Despite their best efforts it had gotten all the way through the interior workings of Ra, coating every surface.

A lot of Earthbound experience was worthless up here. No machine, for example, which used its own weight for leverage was going to be any use. Nevertheless, some terrestrial technologies, like coal gasification, had proven to be good bases for develop-ment of systems that gave a low capital investment and a fast payback.

Greenberg remembered how they'd celebrated when the ore processors had first started up, and water had come trickling out of crushed and heated asteroid cinder. It had touched, he supposed, something deep and human, some atavistic response to the pres-ence of water here, the stuff of life in this ancient rock from space.

Whatever, it had been one terrific party.

And this rock, and many others like it, had proven to be as rich as those old sci-fi-type dreamers, who Greenberg used to laugh at, had hoped. Ra was fat with water - twenty per cent of its mass, locked up in hydrate minerals and in subsurface ice. It exported kerogen, a tarry petrochemical compound found in oil shales, which contained a good balance of nutrients: primordial soup, they called it. Ra pumped out hydrogen, methane, kerosene and methanol for propellants, and carbon monoxide, hydrogen and methane combinations to support metal processing…

And so on.

Ra was just a big volatiles warehouse floating around in the sky. And with the big surface mass drivers that Greenberg called Softball pitchers, Ra products were shipped to places that were volatile-poor - like Mars, lacking nitrogen, and the Moon, dry as a desert. It was a lot cheaper to export them from a rock floating around up here than from all the way at the bottom of Earth's gravity well.

To Greenberg's great surprise, Ra's inhabitants had become rich.

The first justification for opening up the rocks had been to make them serve as short-term resource factories to aid in the colonization of the Moon, Mars and beyond. But it wasn't working out like that. Sure, the gravity well colonies were in place, but they were hardly thriving; they were always going to be dependent on key volatiles shipped in from somewhere else. And they didn't have much to trade; Ra could purchase high-grade metals much more cheaply from other rocks.

There were actually more humans living in the rocks now than on the Moon or Mars. And Ra had more trade with other rocks than anybody else - even Earth…

He saw there was one articulated joint on the splitter boom that was giving particular problems; its prophylactic cover had been taken off, revealing a knobby joint with big, easily replaced parts, already half-dismantled, like the knee joint of a T Rex.

The youngsters were talking about more advances in technology. Like nanotech miners which would chomp their way through the rock without any human intervention at all. Greenberg kind of hoped it wouldn't be for a while, though; he preferred machinery big enough to see, and wrestle with. It gave him a purpose, a reason to use the upper-body strength he'd brought up from Earth.

The workers got out of the way of him, and, whistling, he moved into the balky joint with his vacuum line.

Screw Mars, he thought as he worked; he liked it here.

The remnant of the cloud moulded itself into a flattened, rotating disc. Solid particles condensed: ices of water and hydrocarbons in the cooler, outer rim, but only rocky debris in the hot, churning heart of the nebula. Planetesimals formed, massive, misshapen bodies that collided and accreted as they raced around the new sun.

And, out of the collisions, planets grew: rocky worlds in the hot centre, volatile-fat giants further out. A powerful wind blew from the sun, violently ejecting the amniotic remnants of the birth cloud. Planetesimals rained down on the surfaces of the new worlds, leaving scars that would persist for billions of years.

The gravity of young Jupiter plucked at the belt of planetesimals further in, preventing their coalescence into larger bodies. So, in the gap between Jupiter and Mars, the planetesimals survived as asteroids: rocky chunks closest to the sun, volatile-rich snowballs

at the outer rim, moulded by impacts with each other, melted by radioactivity and electrical induction.

And it was to the asteroids that the starship came: after billions of years drifting like a seed between the stars, still running from the supernova, exhausted, depleted, its ancient machinery cradling the generations that swarmed within, evolving, never understanding their plight.

Scale: Exp 3

The nanobugs woke him; with reluctance he swam up from dreams of sunlit days with his daughters on the beaches of Galveston.

He emerged into a gritty, unwelcome reality. Here he was: half a man, with his whole lower body replaced by the gleaming box he called his PMU, pipes and tubes everywhere, still rattling around inside his clumsy old hab module.

Not that there could be much left of his original home. That old NASA stuff had mostly worn out after a decade, let alone a thousand years. But the Weissmans, or anyhow the robots they'd assigned to keeping him alive, quietly rebuilt this old box around him, just as they rebuilt him continually, nanobugs crawling through his body while he slept away the years.

Well, the hell with it. He dug out a packet of food - the label reassured him it was chicken soup, and as far as he was concerned that was what it was - and he shoved it into the rehydration drawer of his galley.

He moved to a window, the little nitrogen reaction-control squirters on his PMU hissing softly. The window gave onto a shaft cut through the regolith, which had a massive lid that would swing down on him in case of a solar flare or some such. It gave him a good view of the surface of Ra-Shalom, and a slice of the night side of Earth, and a handful of stars.

Water-blue light glared out of Ra.

When he'd first come here, Ra had been just a lump of dirty carbonaceous stone. Now, the old craters and ravines transformed into a patchwork of windows, roofed over with some kind of smart membrane.

Greenberg could see into the lens-like surface of one of the crater windows. And right now, a few minutes from the aero-braking of Toutatis, the Weissmans were swimming up from the big spherical ocean they were building in the hollowed-out inte-

rior of Ra, swimming up to watch a light show hardly any of them understood, probably.

The Weissmans came in a variety of shapes. There were even still a few standard-issue four-limbed humans around. But the most common morphology was something like a mermaid, with the legs

- useless, heavy distractions in microgravity - replaced by a kind of fish tail, useful for swimming around in the air, or the interior ocean. A lot of them had gills and never came out of the water at all, and some were covered in fur that streamlined and warmed their bodies.

The Weissmans had done away with every part of the body which wasn't needed in microgravity. And some had gone further. Some didn't have hands, or arms. In an age of ubiquitous and one hundred per cent reliable machinery - machinery which could manufacture other machinery - human beings, it seemed, didn't need to be toolmakers any more.

To Greenberg, they looked like nothing so much as seals.

It was their choice, or their progenitors anyhow. But what Greenberg couldn't figure was what they did all day.

Greenberg himself still had work to do, in these rare intervals of wakefulness: monitoring Ra's external systems, checking the import of volatile and metal-rich cargoes.

But maybe the Weissmans were just being kind. There were probably gigantic smart systems that backed up every action he took. He was a kind of museum piece, he supposed: the first human to rendezvous with an asteroid, all those years ago, a living totem for the Weissmans of Ra.

He finished the soup and let go of the packet, and a domestic bot - a fussy little bastard like a trash can with attitude thrusters

- came hissing out of its corner and grabbed the bag. Greenberg felt sour, grumpy and isolated.

He studied Earth, which swam past on one of its closest approaches to the rock in years.

He remembered from his first orbital missions aboard Shuttle, all those centuries ago, how the coastal rims of the continents would just glow with artificial light. Greenberg had supposed, then, that it would go on, that the Earth would just get richer and fatter and brighter.

But it hadn't worked out that way. Earth, in fact, grew darker every time he looked.

Once the expansion into the near-Earth rocks had begun, it

wasn't long before a move further out followed: first to Phobos and Deimos, the captured asteroids that circled Mars, and then out into the main belt itself. Vesta, one of the biggest of the main belt rocks, had been the first to be extensively colonized, and now it was the hub of further expansion, little archipelagos of busy mines and colonization, scattered across the belt.

And, so Greenberg understood, there were some pioneers who had gone even farther afield: to the comets out in the Oort Cloud, and the Kuiper Belt, where billions of ice moons the size of Ganymede swam through the darkness.

Of course the techniques they used nowadays made Ra look primitive. Those universal fabricators, for instance, that sucked in asteroid ore at one end and pumped out whatever you wanted at the other, using something called molecular-beam epitaxy to spray atoms and molecules directly onto a substrate. Greenberg didn't understand any of these new gadgets, even the stuff you could see.

It was strange for Greenberg to remember now how much agonizing there had been when he was growing up about the depletion of Earth's resources, the need to close the loops of mass and energy, as if Earth itself was one big CELSS. Nobody worried about that any more; the solar system had worked out to be just too rich in resources; those loops would stay open for a long time yet.

It took a long time for the economics and demographics and such to work out, but it had all been pretty much inevitable, it seemed to Greenberg. It was just so much cheaper to send resources skimming between the rocks than to haul them out of the planets' big gravity wells. The colonies on Mars and the Moon had shrivelled and died, and Earth - growing poorer, its population steadily declining - had turned into a kind of huge theme park: a museum of the human species, but studded with pits of abject poverty, in the darkened ruins of the old cities. Nobody knew what was happening in those pits.

And nobody much cared, because beyond old Earth there were too many people even to count.

If you knew where to look, the sky was full of inhabited rocks, with their little orbital necklaces of solar power stations, and habitats studding their surfaces or buried inside, green and blue, the old colours of life. It was estimated that for every person alive when Greenberg was born, there were a billion human souls now. That was a hell of a thought. And when he considered some of

the assholes he used to have to work with back in those days, a dismaying one.

In Ra there was a whole bunch of little Weissmans, though not all of them used Mike's old name any more, and so in his head Greenberg thought of them all as Weissmans; it made it easier to love them. Mike would have been pleased, anyhow. There were no Greenbergs, though. His line had finished with a great-grandchild, a male, who had got caught up in the New AIDS epidemic of the twenty-second century, and died childless. It was ironic. Here was Greenberg, perhaps the oldest surviving human, and not one of all those teeming trillions floating around the system could claim direct descent from him.

On the other hand, by the laws of statistics, there ought to be a billion Einsteins out there. Nobody knew what they were all doing. They sure weren't working together.

All those pious dreams of the space buffs of some kind of giant solar-system civilization had never been remotely likely. There were just too many people. The human race had gathered into a billion small-town-sized tribes and splintered, shaping and seeking goals unimaginable to an Earth-born geezer like him.

It seemed to him, in fact, that he was watching the end of the species, as a unitary whole: two million years out of Africa, the race had escaped from the cradle and was growing, to where the hell nobody could even guess.

… And now here came Toutatis on its aerobraking pass.

The rock looked like a comet glowing in the thin upper air of Earth, streaking by in a perfect straight line below Greenberg. It made the cities and oceans of Earth glow like the day - it must have been a remarkable sight from down there - and asteroid light played on his own face, the ancient bones of his eye sockets.

The encounter was over in seconds. The trail of scorched air soon dissipated and dimmed, and Toutatis, its orbit subtly altered, passed on towards its next encounter. It was going to take fifty years to nudge Toutatis into its final low Earth orbit, but planning projects on that kind of time scale didn't seem to trouble the inhabitants of Toutatis, or anybody else.

The show was over. The people of Ra-Shalom drifted away from their blue watery windows, and returned to their mysterious business within.

Greenberg had never meant to live for a thousand years. It was ridiculous. Nobody else had stuck around like this. It was just

that he would have had to have chosen when to die, and that was something he had never expected to face when he grew up, and he just had no instinct for it.

Anyhow, if he let himself die, he would have missed this.

Greenberg, with a sigh, turned away from the window and went to his instrument consoles.

It was a massive asteroid, big enough to have dragged itself into a sphere, with planet-like layers of internal structure, rich in metals, rocks and volatiles. It was bathed by the light of a sun only three times as far away as from Earth.

The guardians considered carefully. It was, after all, to be the repository of all that was left of their designers' species, until even this new young sun guttered and died.

They were machines designed to plan for billions of years. They had already nursed their fragile cargo across such deserts of time. Now, looking to the future, they must plan for evolution, even the loss of mind.

It was a good home, rich in energy and resources.

The guardians were satisfied. They closed themselves down.

Within the rock, history continued.

Scale: Exp 4

It was to be quite a day, as the last of Ra's ore was transmuted, and Greenberg made sure the Weissmans woke him up to see it. In the event he nearly missed it, it took so long to put him together again.

Greenberg's window was the same old tunnel through fused regolith, but the view beyond changed as he watched, the last of the grey-black old crap literally dissolving before his eyes, to be replaced by a sharp, tight blue curve of watery horizon.

Too damn sharp, he thought. He wondered if those asshole nanobugs had changed his eyes on him again while he'd slept. But even his naps lasted a century at a time, longer than he had once expected to live; they had time.

Anyhow, his new eyes showed him a blue world, the landscape softly pulsing, with Greenberg's NASA-style space station hab module stuck stubbornly to the side under its crust of regolith, like a leech clinging to flesh. Ra was just water now, encased by some smart membrane that held the whole thing in place and collected solar energy and regulated temperature and stuff. It

looked like a little clone of Earth, in fact, and Greenberg thought it was somehow appropriate that today that tired, depopulated old Earth itself was over somewhere the far side of the sun, invisible, forgotten, the last traces of man being scraped off by the returned glaciers.

Under the pulsing surface of Ra he could make out dark brown shapes, graceful and lithe: people, Weissmans, whole schools of them flipping around the interior. And now here came a child, wriggling up to the membrane, pushing its disturbingly human face up to the wall, peering out - with curiosity or indifference, he couldn't tell which - at the stars. It broke his unreconstructed twentieth-century heart to see that little girl's face stuck on the end of such a fat, unnatural body.

An adult came by and chivvied the kid away, into the deeper interior; Greenberg saw their sleek shapes disappear into the misty blue.

The Weissmans had been working on making their environment as simple and durable as they could. They were planning for the long haul, it seemed. So, the whole rock had been transformed into this spherical ocean, and the biosphere had been cut down to essentially two components: Weissmans, post-humans, swimming around in a population of something that was descended from blue-green algae. The algae, feeding on sunlight, were full of proteins, vitamins and essential amino acids. And the humans ate the algae, drank the water, breathing in oxygen, breathing out carbon dioxide to feed the algae.

When people died their bodies were allowed to drift down to the centre of the world, where supercritical water reactors worked to break down their residues and return their body masses to the ecosystem.

The loops were as closed as they could be. The loss that entropy dictated was made up by the energy steadily gathered by that smart membrane, and a few nanobugs embedded there. Greenberg understood that research was going on to eliminate the last few technological components of the system: maybe those supercritical water reactors could be replaced by something organic, and maybe even the surface membrane and the last nanobugs could be done away with. For instance, a few metres of water would serve as a radiation shield.

It was a kind of extreme end result, Greenberg supposed, of the technology evolution that had begun all the way back with John

Glenn in his cramped little Mercury tin can, breathing in canned air for his few orbits of the home planet.

But the Weissmans were not much like John Glenn.

He didn't know any of their names. He didn't care to. For a long time now, longer than he cared to think, there had been hardly anybody alive who remembered him from one waking period to the next, from one of his 'days' to another. Hell of a thing. He preferred to talk to the machines, in fact.

Greenberg didn't even know if the Weissmans were still human any more.

The last of the true humans, as he recognized them, had been leaving the system for millennia.

It had been necessary. For a time, as the human population grew exponentially, it looked as if even the solar system's vast resources were in danger of depletion.

So somebody had to leave, to open up the loops once more.

There was a whole variety of ways to go, all of them based on pushing people-laden rocks out of the system. You could mount a big mass driver on the back of your rock and use its substance as reaction mass. Close to the sun, you could use its heat to just boil off volatiles. You could use a solar sail. You could use Jupiter's powerful electromagnetic field as a greater mass driver. And so on. There was even a rumour of an anti-matter factory, out in the Kuiper Belt somewhere.

Greenberg's favourite method was the most resolutely low-tech. Just nudge your rock out of its stable orbit, let it whip through the gravity fields of Jupiter and Saturn a few times, and you could slingshot your way out of the system for free. Of course it might take you ten thousand years to reach your destination, at Barnard's Star or E Eradini or E Indi. But what the hell; you probably had with you more water than in the whole of the Atlantic Ocean.

Greenberg accepted the necessity of the migration. But to him it had been a drain, not just on the system's titanic population, but on the human spirit.

The solar system had been left a drab, depopulated place. All the engineering types had gone, leaving behind the navel-gazing seals of Ra, and similar relics scattered around the system.

The Weissmans, turned in on themselves, had their own interests. They were probing into a lot of areas well beyond his expertise. Like the possibility of tapping into zero-point field

energy, the energy of the vacuum itself, so dense you could - it was said - boil all the oceans of Earth itself with the energy contained in a coffee cup of empty space. Then there was the compact energy stored in topological defects, little packets of space that had gotten tangled up and folded over in the Big Bang, containing some of the monstrous primeval energies within, just waiting to be tapped and opened up…

Research and development, carried on by a community of goddamn seals, with no hands or tools. Greenberg didn't know how they did it. It was one of the many things about the Weissmans he didn't understand.

He did know they were trying to extend their consciousness. Mind, it seemed, was a quantum process, intimately bound to the structure of space and time. And in space, after ten thousand years free of the distortions of the muddy pond of atmosphere at the bottom of Earth's gravity well, consciousness - the Weissmans claimed - was taking a huge evolutionary leap forward, to new realms of power and control and depth.

Maybe.

To Greenberg, it was all very well to dream of super-minds of the future, but right now, he suspected there was nobody left, for instance, who was giving thought to pushing a troublesome asteroid out of its orbit, where once the children of man had rearranged worlds almost at will.

And, Greenberg was coming to realize, that might make a big difference in the future.

He still had some of his old monitoring systems, or patiently reconstructed copies anyhow. He studied Ra's evolving trajectory around the sun.

And, gradually, he'd learned something that had disturbed him to his core.

Near-Earth asteroids wandered in steadily from the main belt, their orbits tweaked by the gravity of Jupiter, Venus, Mars and Earth itself. They hung around for thirty megayears or so, their orbits slowly evolving. Then they would encounter one of three fates, with equal probability: they would hit Earth, or hit Venus, or be slingshot out of the system altogether.

The cratering record on Earth showed this had been going on tor billions of years. The smaller the object type, the more frequent the collision. Every few thousand years, for instance, Earth would be hit by an object a hundred metres or so across, big enough to

dig out a new Meteor Crater, as in Arizona, where Apollo Moonwalkers had once trained. Earth had actually suffered a few fresh strikes like that while Greenberg had been observing.

And every few tens of millions of years, a much larger body would strike.

Such an object had struck the Earth sixty-five million years ago, at Chicxulub in Mexico. It had caused the extinction of most of the species extant at that time.

It was known as the dinosaur killer.

Earth was overdue for another impact like that.

Near-Earth asteroid orbits were pretty much chaotic. It was like the weather used to be, back when he lived in a place that had weather. But as computers had gotten smarter, the path of Ra-Shalom had been pushed out, in the computer's digital imagination, further and further. Finally it had become clear to Greenberg what Ra's ultimate fate would be.

Ra wasn't going to hit Venus, or be thrown out of the system to the stars. Ra was going to hit Earth.

Ra was the next dinosaur killer.

It was a long time ahead: all of a million years from now. But it worried him that right now, nobody seemed to know how to deflect this damn rock.

Whenever he got the chance, he sounded off about the dinosaur killer problem. The Weissmans told him they had plans to deal with it, when the time came. Greenberg wasn't sure whether he believed that.

And he wasn't sure he wanted to be around to see this chewed-up rock auger in on the surface of the planet where he was born. But he couldn't turn his back.

Within the confines of the tiny world, civilizations fell and rose; by turns, the refugee race fell to barbarism, or dreamed of the stars. The guardians had planned for this.

But the little world was not stable. This they had not antici-pated.

Its orbit was close to a resonance with that of Jupiter: it circled the sun three times in each of Jupiter's stately years. The powerful tug of Jupiter worked on the asteroid's trajectory, millennium after millennium.

Quite suddenly, the orbit's ellipticity increased. The asteroid started to swing deep into the warm heart of the solar system.

There was nothing the inhabitants could do to steer their rock. Some adapted. Many died. Superstitions raged.

For the first time, the asteroid dipped within the orbit of Earth.

Scale: Exp 5

... Crossing time in unimaginable jumps, drifting between sleeping and waking, eroding towards maximum entropy like some piece of lunar rock…

He never knew, he didn't understand, he couldn't believe how much time had passed. A hundred thousand years? It was a joke.

But even the sky was changing.

The nearby stars, for instance: Alpha Centauri and Barnard's Star and Sirius and Procyon and Tau Ceti, names from the science fiction of his youth. You could see the changes in the light, the stain of oxygen and carbon, chlorophyll green. Even from here you could see how humans, or post-humans anyhow, had changed the stars themselves.

And to think he used to be awed by the Vehicle Assembly Building at Canaveral.

And the expansion must be continuing, further out, inexorably. On it would go, he thought dimly, a growing mass of humanity filling up the sphere centred on Sol, chewing up stars and planets and asteroids, until the outer edge of the inhabited sphere had to move at the speed of light to keep up, and then what would happen, he wanted to know?

But none of that made a difference here, in the ancient system of Sol, the dead heart of human expansion. It was hard for him to trace the passing of the years because so little changed any more, even on the heroic timescales of his intervals of consciousness.

Conditions in a lot of the inhabited rocks had converged, in fact, so that the worlds came to resemble each other. Most of them finished up with the kind of simple, robust ecosystem that sustained Ra, even though their starting points might have been very different. It was like the way a lot of diverse habitats on Earth -forests and jungles and marshes - would, with the passage of time, converge into a peat bog, the same the world over, as if they were drawn to an attractor in some ecological phase-space.

And most of the rocks, drifting between uninhabited gravity wells, were about as interesting as peat bogs, as far as Greenberg was concerned.

Meanwhile, slowly but inexorably, life was dying back, here in the solar system, which had once hosted billions of jewel-like miniature worlds.

There were a lot of ways for a transformed asteroid to be destroyed: for instance, a chance collision with another object. Even a small impact on a fragile bubble-world like Ra could puncture it fatally. But nobody around seemed capable of pushing rocks aside any more.

But the main cause of the die-back was simple ecological failure.

An asteroid wasn't a planet; it didn't have the huge buffers of mass and energy that Earth had. A relatively small amount of matter circulated in each mass loop, and so the whole thing was only marginally stable, and not always self-recovering.

It had even happened here, on Ra-Shalom. Greenberg had woken once to find concentrations of the amino acid called lysine had crashed. The Weissmans were too busy on dreaming their cetacean dreams to think too much about the systems that were keeping them alive. Many died, before a new stability was reached. It drove Greenberg crazy.

But the Weissmans didn't seem too upset. You have to think of it as apoptosis, they said to him. The cells in the hands of an archaic-form human embryo will die back in order to sculpt out tool-making fingers. Death is necessary, sometimes, so that life can progress. It is apoptosis, not necrosis…

Greenberg just couldn't see that argument at all.

And in the meantime, Ra was still on its course to become the next dinosaur killer. The predictions just got tighter and tighter. And still, nobody seemed to be concerned about doing anything about it.

When what the Weissmans said to him made no sense at all -when they deigned to speak to him - Greenberg felt utterly isolated. But then, all humans were alone.

Nobody had found non-terrestrial life anywhere, in the solar system or beyond, above prokaryotes: single-celled creatures without internal structures such as nuclei, mitochondria and chloroplasts. Mars was typical, it had turned out: just a handful of crude prokaryote-type bugs shivering deep in volcanic vents, waiting out an Ice Age that would never end. Only on Earth, it seemed, had life made the big, unlikely jump to eukaryotic structure, and then multi-celled organisms, and the future.

It seemed that back when he was born Earth had been one little

world holding all the life there was, to all intents and purposes. And it would have stayed that way if his generation and a couple before, Americans and Russians, hadn't risked their lives to enter space in converted ICBMs and ridiculous little capsules.

Makes you think, he reflected. The destiny of all life, forever, was in our hands. And we never knew it. Probably would have scared us to death if we had.

For if we'd failed, if we'd turned ourselves to piles of radioactive ash, there would now be no life, no mind, anywhere.

Gravitational tweaks by Earth and Venus gradually wore away the asteroid's energy, and its orbit diminished. The process took a hundred million years.

At last, the asteroid with its fragile cargo settled into a circle, a close shadow of Earth's orbit. Its random walk across the solar system was complete.

The inhabitants adapted. They even flourished, here in the warmer heart of the solar system.

For a time, it seemed that a long and golden afternoon lay ahead of the refugees within the rock. Once more, they forgot what lay beyond the walls of their world…

But there seemed to be something in the way.

Scale: Exp 6

We have an assignment for you.

He came swimming up from a sleep as deep as death. He wondered, in fact, if he was truly in any sense alive, between these vivid flashes of consciousness.

… And Earth, ocean-blue, swam before Ra, a fat crescent cupping a darkened ocean hemisphere, huge and beautiful, just as he'd seen it from a Shuttle cargo bay.

In his vision there was water everywhere: the skin of Earth, the droplet body of Ra-Shalom, and in his own eyes.

We have an assignment for you. A mission.

'What are you talking about? Are you going to push this damn rock out of the way? I can't believe you've let it go this far.'

This has happened before. There has been much apoptosis.

'Hell, I know that…'

He looked up at a transformed sky.

Everywhere now, the stars were green.

There was old Rigel, for instance, one of the few stars he could

name when he was a kid, down there in Orion, at the hunter's left boot. Of course all the constellations had swum around now. But Rigel was still a blue supergiant, sixty thousand times more luminous than the sun.

But now even old Rigel had been turned emerald green, by a titanic Dyson cloud twice the diameter of Pluto's orbit.

Not only that, the people up there were starting to adjust the evolution of their giant star. Rigel only had a few million years of stable life - compared to Sol's billions - before it would slide off the Main Sequence and rip itself apart as a supernova.

But the people up there were managing Rigel, managing a goddamn supergiant, deflecting its evolution into realms of light and energy never before seen in the history of the universe. And that emerald colour, visible even to a naked archaic human eye, was the symbol of that achievement.

It was a hell of a thing, a Promethean triumph, monkey paws digging into the collapsing heart of a supergiant.

Nobody knew how far humans had got from Earth, or what technical and other advances they had achieved, out there on the rim. But if we don't have to fear supernovas, he thought, we need fear nothing. We've come a long way since the last time I climbed into the belly of a VentureStar, down there at Canaveral, and breathed in my last lungful of sea air…

… an assignment, the Weissmans were saying to him.

Earth swam close, and was growing closer.

We want to right the ancient necrosis as far as we can. We want you to help us.

'Me? Why me?'

It is appropriate. You are an ambassador from exponent zero. This is a way of closing the loop, in a sense. The causal loop. Do you accept?

'I don't know what you're talking about. I accept. I don't know what you mean…'

... The walls of the hab module dissolved around him. Suddenly he didn't have hold of anything, and he was falling.

Oh, shit, he thought.

But there were shadows around him, struts and blocks. And a heavy, liquid mass at his lower body he hadn't felt for a long time. Legs. He had legs.

His breathing was loud in his ears. Oxygen hissed over his face. He was back in his Shuttle-era pressure suit, and he was encased

in his PMU once more, the original model, its spidery frame occluding the dusting of stars around him.

He grasped his right-hand controller. It worked. There was a soft tone in his helmet; he saw a faint sparkle of exhaust crystals, to his left.

Still, Earth swam before him. It is time. 'Wait - what -' Earth was gone. Ra-Shalom sailed through the space where the Earth had been, its meniscus shimmering with slow, complex waves as it rolled, the life at its heart a dim green knot against the blue.

My God, he thought. They pushed Earth aside. I didn't know they got so powerful -

'What did you do? Is it destroyed?'

No. Earth is in a stable orbit around Jupiter. The ice will return, for now. But later, when the sun starts to die, Earth will be preserved, as it would not have been -

'Later?'

We must plan for exponent seven, eight, nine. Even beyond. The future is in our hands. It always has been. 'But how -'

Goodbye, the Weissmans said, a tinny voice in the headphones in his Snoopy hat. Goodbye.

And now there was another hulking mass swimming into view, just visible at the edge of his faceplate.

He worked his attitude thrusters, and began a slow yaw. Strange, he didn't seem to have forgotten any of the old skills he had practised in the sims at Houston, and in LEO, all those years ago.

He faced the new object.

It was an asteroid. It looked like Ra-Shalom - at any rate, how that rock had looked when he first approached it - but it was a lot bigger, a neat sphere. The sun's light slanted across craters and ravines, littered with coal-dust regolith. And there was a structure there, he saw: tracings of wire and panelling, bust up and abandoned, and a big affair that stuck out from the rock, a spider-web of wires and threads. Maybe it was an antenna. Or a solar sail.

Artefacts.

It looked like the remains of a ship, in fact. But not human. Not human. My God, he thought.

And now the light changed: to the stark planes of the sun's eternal glow was added a new, softer glow. Water blue.

He turned, clumsily, blipping his attitude thrusters.

Earth was back, a fat crescent, directly ahead of him. This is a hell of a light show, he thought.

But Earth looked different. It had spun around on his axis. Before he'd been over the Pacific; now he could make out, in a faint dawn glow, the familiar shapes of the continents - North and South America, painted over the ocean under bubbling wisps of cloud.

There were no lights, anywhere. And the arrangement of continents didn't look right. Earth didn't match his memories of schoolroom globes, under the Stars and Stripes, back in Iowa.

The Atlantic looked too skinny, for instance.

This new rock was heading for Earth, just like Ra-Shalom had been. It couldn't be more than a few minutes from reaching the atmosphere. And it looked to him as if it was going to hit somewhere in Mexico…

Oh, he thought. I get it.

This was the dinosaur killer, the original, destined to gouge out a two-hundred-kilometre crater at Chicxulub, and to have its substance rained around the planet.

He shielded his eyes with a gloved hand, and studied the stars.

They were different. The stars were bone white: no green, anywhere.

He was displaced in time, a long way. But this was not the far future, but the deep past.

He turned again to face the plummeting rock, with its fragile cargo of artefacts.

One last time the kerosene thrusters fired, fat and full. The asteroid started to approach him, filling his sky. The suit was quiet, warm, safe.

He just let himself drift in, at a metre or so a second. The close horizon receded, and the cliff face turned into a wall that cut off half the universe.

He collided softly with the rock. Dust sprays were thrown up from around the PMU's penetrator legs. Greenberg was stuck there, clinging to the surface like a mountaineer to a rock face.

He turned on his helmet lamp. Impact glass glimmered a few centimetres from his' face. He reached out and pushed his gloved

hand into the compacted-snow surface, a monkey paw probing.

… There was something here. Something alive, something sentient, inside the rock. He could feel it, though he couldn't tell how.

Maybe the Weissmans were using him as some kind of conduit, he thought. Maybe they wanted to save some of whatever was here from the destruction of the rock, take it with them to whatever future awaited mankind.

Or maybe it was just him.

He smiled. He was a million years old after all; maybe a little of the Weissman had rubbed off on him.

He took a handful of dust and pulled out his hand. A cloud of dust came with it that gushed into his face like a hail of meteorites, glittering particles following dead-straight lines.

He sensed acceptance. Forgiveness. He wondered how far they'd come, how long they'd travelled. What they were fleeing.

Anyhow, it was over now.

'You weren't alone,' he said. 'And neither were we.' He pushed his hand back into the pit he'd dug, ignoring the fresh dust clouds he raised.

The light of Earth billowed around him.

Glass Earth, Inc.

'You lied to me.' I don't understand.

'You lied about the murder. Have you lied to me all my life? Is it just me, or do other Angels do this too?'

Rob, I don't mean you any harm. My sole purpose is to serve you.

'Because of you I don't know what's real any more…'

It is the year 204;. Don't be afraid.

For Rob Morhaim, it started as just another assignment.

Morhaim checked his reflection in the Cinderella mirror on the softwall. Not that he expected to meet anybody in person today - that hardly ever happened - but it made him feel better. The mirror showed him Cary Grant circa 1935- incongruously dressed in Metropolitan Police light armour, circa 2045 - but it was honest enough to show him any smuts on his nose, and that he needed a shave.

But the mirror was infested; Cary Grant started to sprout a ridiculous Groucho Marx moustache and cigar. 'Goddamn viruses. Off.'

The mirror metamorphosed to a neutral view of a Thames river-scape, under a parched June sky. The view was overlaid by a tampon ad: irrelevant to Morhaim since his divorce, of course, but still counting to his ad quota.

Nothing much we can do about the viruses, murmured the Angel. Since the passing of the sentience laws -

Morhaim fixed himself a coffee and a Coca-Dopa marijuana

cigarette. 'I know, I know. But where the hell are the Goodfellows when you need them?…' He settled in his chair.

The Room, his home, was just a softwall box, with a single office chair, and a caffeine/Dopa vending machine. Its bio equipment - a bed, a kitchen, a bathroom - folded away when he didn't need it. He was a cop in a box, one of thousands in New New Scotland Yard: a Virtual warren of Rooms, of cops in boxes, physically separated, their softwalls linking one to another.

Nobody travelled any more…

You want to take your ads?

'Do it.'

Morhaim stared straight ahead as a melange of graphics, letters and smiling faces blizzarded over the wall in front of him.

Most of the ads that, for statutory reasons, survived the Angel's filtering were dominated by the big companies - Microsoft-Disney, Coke-Boeing, IG Farben. Morhaim could never see why they couldn't do a little pooling, thus reducing the quota for everyone. Some of the images were crudely three-dimensional, popping out of the softwall in front of him, though they still hadn't got that stuff right and the images tended to break up into pixels, light-filled boxes, around the edges. More insidious were the you-ads, ads that were tailored to him - shouting his name, for instance, or Bobby, the name of his kid.

He let his eye follow the action - the in-wall retinal scanners could tell if you closed your eyes, or even if you let yourself glaze over - and, unless your attention was caught, you wouldn't be allowed to tally to your quota.

At last the battering of light and noise died.

When he checked the time he found he'd got through the best part of his legal duty as a consumer in a half-hour, a good performance by any standard, even if it did leave his eyes feeling like poached eggs.

And all the time, somewhere in his head, he was thinking about The Case.

With relish, he said: 'Time to go to work, Angel.' The softwalls dissolved, even the Cinderella mirror, and Morhaim was suspended over Tower Bridge.

When they were proven to be alive, by legal definition anyhow, you granted viruses amnesty.

Manufacturers of virus killers were shut down; even virus check software is illegal. In fact it is part of the remit of Rob Morhaim's unit of the CID to track down breaches of those laws.

But there are supposed to be two sides to the bargain: the Robin Goodfellows, the most human-like products of virus evolution, have committed to keep their more mischievous junior companions under control. Mostly they do just that…

Possibly.

But things seem to be sliding a little right now, as most of you realize. A lot of commentators blame the approach of the Digital Millennium - 2048, the year 100000000000 in binary, requiring a whole extra digit from 2047, which was 11111111111 - when, street scuttlebutt has it, the storage problems required by that extra digit will deliver the catastrophe we managed to avoid at the 2000 date change.

Perhaps you are right. Perhaps rogue viruses, or the approach of the Digital Millennium, are indeed at the root of everything that is going wrong for you.

Perhaps not.

… And now here was Morhaim at a pov that looked down over the crime scene: two days ago, Wednesday June 2045, at 10.53 a.m., five minutes before the event. The sun was bright and high, the light dripping down from a sky that was whited-out and without a shred of ozone, and the twin towers of the Bridge sparkled like a fairy castle. Further down the river he could see the city's newest bridge, a gaudy, over-familiar M-shape curve in bright corporate yellow: an eyesore for traditionalists, but welcomed by Londoners as a painless hit against the ad quota… The view was neutrally interpreted. Evidently he was seeing through a dumb camera, a simple imager with little more sentience than a cockroach.

Tower Bridge's road span was lowered right now, and Morhaim was looking down at a ribbon of colourfully clad pedestrians and smart-trams, weaving their complex paths across the Thames. And among those crowds - gazing up, perhaps, at the big aerostats floating across London pumping out ozone, or down at what was left of the Thames, a sluggish, carefully managed trickle a quarter of its former size, or just staring at the people - was Cecilia Desargues, forty-three years old, entrepreneur, founder and chief executive of Glass Earth, Inc. - Cecilia Desargues, about to meet her death.

Subject is stepping onto the Bridge roadway. From the south side.

'Let's go see her.'

The pedestrians froze. His pov descended smoothly, like a swooping bird. The pov reached an adult's eye level, and Morhaim was in the crowd.

People, their lives freezeframed in the sunshine like photographed billows of smoke: a family of fat Nigerians, a huddle of Asiatic businesswomen - Korean or Thai probably - against a background of evidently British faces, many of them bearing that odd blend of Asian and Anglo-Saxon that characterized so many Londoners now. No Europeans, of course, since the French had shut down the Chunnel following the prion plagues, and no Americans, scared away by the activities of the Wessex Liberation Front. All of them wore their sunhats and Angel headsets - smart glasses - mostly draped with corporate logos: everyone working to hit their one-hundred-thousand-a-day ad quota as painlessly as possible.

But this was sparse, compared to the crowds Morhaim remembered from his youth. And most of the tourists were old, with very few middle-aged - that generation would be watching from a Room somewhere, like himself - and, of course, hardly any kids. Nowadays, the dwindling numbers of young humans were too precious to be risked outdoors.

But there was, he noticed, a clutch of teenagers, leaning against the rail, peering out at what was left of the river - oddly hard to make out, just skinny outlines around blurred patches, coated by softscreen tattoos.

'Play.'

The images came to life, and a bustle of voices washed over Morhaim.

The kids came out a little clearer; the softscreen tattoos that coated their flesh, turning them all but transparent, had some trouble processing their images when the kids moved, and every so often a softscreen would turn black, an ugly patch against young skin, an arm or leg or shoulder.

These were the Homeless.

The kids, without speaking, left the rail and walked away from the pov. They moved like ghosts, Morhaim thought. 'Damnedest thing.' Yes.

'There but for the grace of God -'

- goes Bobby in a couple of years, the Angel completed for him. I understand.

Morhaim's pov moved forward, through dissolving crowds. And there, in the middle of the tableau, was Cecilia Desargues herself: a compact, stocky Frenchwoman, her face broad, cheerful and competent, her hair uncompromisingly grey. On the breast of her jumpsuit she wore a Day-Glo flashing 1/24 symbol, the logo of her company, Glass Earth, Inc. One twenty-fourth of a second: the maximum signal time lag between any two points on the globe in the future, beating the pants off the satellite operators. So promised Glass Earth, Inc., anyhow.

Desargues was standing in the middle of the pavement, looking at the crowds. Evidently waiting.

'She has an appointment.'

Yes.

'With her killer?'

Not as it turned out. Do you want me to freezeframe? 'Not this first time. Let's just watch…'

Rob Morhaim thinks about children a lot.

His own child, Bobby, is very precious to him. Much more precious than his failed marriage, in fact.

He has that in common with most people of his generation. Adult relationships can involve pairings of any of the eight main sexes, are only rarely formalized by marriage, and come and go like the seasons. But child-bearing - in an age where male fertility is only a few per cent of what it was a century ago - is the emotional cornerstone of many lives.

Perhaps of your own.

Even so, population numbers are collapsing, all over the planet… Your children are the last protected species.

End of the world, say your doom-mongers. But they have been wrong before.

You perceive threats which don't exist. Perhaps you don't perceive the threats that do exist.

A man emerged from the crowd. He was maybe thirty, medium height. His head was hidden by his sun-hat, of course, but his high forehead indicated he might be balding. He wore a standard-issue business suit that wouldn't have looked out of place,

Morhaim thought, a century ago. But his sunhat was a little less sombre: something like a beanie cap, with six or seven little satellites orbiting his Earth-coloured cranium.

Morhaim recognized the logo. 'He's from Holmium,' he said.

Yes. He's called Asaph Seebeck. He's more senior than he looks in the corporation, for his age. Smart cookie. Details are -

'Later.'

The young man started moving towards Desargues, across Morhaim's field of view.

Holmium was a comsat operator, Swiss-based, worth billions of Euros. It was named after the element, holmium, which had an atomic number of sixty-seven, the same as the number of microsatellites the corporation operated in geosynchronous orbit.

If Desargues' extravagant claims about her company's revolutionary technology were true, Holmium was among those most likely to lose out. In a big way.

Morhaim tried to take in the scene as a gestalt. The two principles were coming together across a stage crowded with extras playing tourist. Among the extras, over there walked a pretty girl of the kind Morhaim liked - slim, dark, pert breasts, long legs free of tattoos, walking away from his pov, looking up at one of the Bridge towers - and now, when Morhaim looked away from the girl, he saw that Seebeck and Desargues had made eye contact.

They moved together more purposefully. Morhaim could see Desargues' face; it was assembling into a smile.

They're going to speak. Enhancement is available to -

'Not yet. Just run it.'

They met face to face, smiled, exchanged three lines of dialogue. Morhaim strained to hear, through the background noise wash. '… Machine Stops…' said Seebeck. 'Pardon? Well. I'm… see me, Mr Seebeck.' '• - . sorry?'

And then the shot came.

Crime among you is, frankly, uncommon in this year 2.045. The ubiquity of cameras, callosum dumps and other monitors has seen to that. And the rules of evidence have gradually evolved to admit more and more data gathered by non-human means. The court system - even police work - has been reduced almost to a rubber-stamping of the deductions of faceless expert systems.

Rob Morhaim knows that his precious CID is a fraction of the

manpower it was a few decades before. Most coppers now serve as muscle to implement the decisions of the courts, or the social services, or - most commonly - the recommendations of the smart systems. Yes: even now, on the brink of the Digital Millennium, there is still need for a poor bloody infantry to 'meet the meat', as the plods call it.

In the meantime, we do the real work.

Thus, you let us guard you, and watch you.

You even trust us to judge you.

Desargues stumbled forward, as if she had been punched in the back.

She actually fell into Seebeck's arms, Morhaim saw; but before she got there the Virtual imagery turned her into a stick figure, with a neat hole drilled in her torso.

The Angel knew Morhaim didn't need to be shown the details of Desargues' injury. And so it filtered, replacing Desargues with a bloodless Pinocchio. He was silently grateful.

Seebeck clumsily tried to catch her, but she slid down his body and landed at his feet with a wooden clatter. People started to react, turning to the noise of the shot - it came from the Bridge's nearest tower - or to the fallen woman.

'Freeze.'

The Virtual turned into a tableau, the sound ceasing, devoid of human emotion - blessedly, thought Morhaim. He studied faces: bewilderment, curiosity, shock, distorted faces orbiting the dead woman like Seebeck's circling satellites.

The ballistic analysis was clear. There was a single shot. There is no doubt it killed her, and no doubt where it came from.

'The Bridge tower.'

From a disused winch room. The bullet was soft-nosed. It passed through her body and took out the front of her chest cavity before -

'Enough. Leave it to the coroner.'

He was studying Seebeck. He saw shock and fear written on the Holmium man's face. And his suit was - marred somehow, the image blurred.

Covered with pieces of Cecilia Desargues.

In the winch room was found a high-velocity rifle, which had fired a single shot -

'Which matched the bullet that killed Desargues.'

Yes. And a card, bearing the phrase -

An image, hovering in the Virtual, a grubby card:

THE MACHINE STOPS

'What was it Seebeck said at the start? Something about a Machine?'

Yes. The winch room also contained a directional mike. The phrase was evidently a verbal trigger, a recognition signal…

And so, Morhaim thought, it comes together. Nestling like the cogs of a machine.

The Homeless are a new cult group among your young, a strange mixture of scientific and Zen influences. Popular, despite the protestations of the Reunified Christian Church.

It is a cult of non-existence of the self, thought to be a consequence of the way you explain ourselves and your world to your young. Science and economics: science, which teaches that you come from nothing and return to nothing; economics, which teaches you that you are all mere units, interchangeable and discardable. Science is already a cult of non-existence, in a sense. Homelessness is simply a logical evolution of that position.

They aren't literally homeless, of course. The most extreme adherents coat their bodies in image tattoos, hiding themselves utterly…

They are a puzzle. But they are your young, not ours.

'So,' Morhaim said to his Angel, 'you think Holmium were responsible.'

Cecilia Desargues' company is small and entrepreneurial, still heavily dependent on her personality. Her elimination immediately wiped much value from the company's stock. The involvement of a Holmium employee in such an unambiguous role at this critical moment -

'Yeah. It all points that way.'

… But in slomo, the shock and horror spreading across Seebeck's moonlike face seemed unmistakeable. The rest of the brief conversation, when he'd heard it all unscrambled, had been odd, too.

The Machine Stops… Pardon? Well. I'm intrigued you asked to see me, Mr Seebeck… I'm sorry?

After the code phrase, it looked for all the world like the interchange of two people who didn't know why they were meeting.

As if Seebeck thought Desargues had asked to meet him - for some odd reason in RL, in this public place - but Desargues thought the opposite, that Seebeck had asked to meet her…

As if some third party had set them up, to come together. Was it possible Seebeck was some kind of patsy? - set up to repeat a phrase whose significance he didn't understand?

It was Morhaim's job to approve what he'd seen, and the conclusions the Angels had drawn, and pass it up the line. And he ought to sign this off and move on.

The evidence against Holmium was circumstantial. But what the smart systems had turned up here was surely enough for a court order to start digging into Holmium, and it was a good bet that before long more substantial evidence of a conspiracy to murder would come to light.

And yet…

And yet, he liked to think he had retained something of the instincts of the coppers of London past. Something didn't smell right. 'I think,' he said, 'that somebody's lying here.'

He told the Angel to put him through to Asaph Seebeck, who was being held at Westminster Police Station.

When Morhaim came to haunt Seebeck, the cell's softwalls carried only images from a movie - the centenary remake of Casablanca, with a coloured, hologram Bogart growling through his modernized lines to a sulky Pamela Anderson. Morhaim knew that the cell's electronic confinement, hemmed around by software firewalls, would be far more enclosing, to a man like Seebeck, than the physical cage.

In his disposable paper coveralls, Seebeck looked young and scared.

Morhaim questioned Seebeck, aware that the man's Angel was also being pumped for data by intelligent search agents in a ghostly parallel of this interrogation.

Seebeck denied any involvement with the murder of Desargues, over and over.

'But you must see the motive that can be imputed,' said Morhaim. 'Desargues said she had a key competitive edge over you guys. She was planning a global comms network which wouldn't suffer from the transmission delays your systems throw up, because of having to bounce signals all the way to geosynch orbit and back -'

•Which will allow us to merge communities separated by oceans, or even the full diameter of the planet. Which will allow us finally to establish the global village. Which will make comsats obsolete ... All those grandiose claims. Blah, blah.'

'If Desargues was right - if her new technology could have put your company out of business -'

'But it wouldn't,' Seebeck said. 'That's the whole point. Don't you see? Satellite technology will not become obsolete overnight. We'll just find new uses.'

'Like what?'

'I'll show you.'

With Morhaim's permission, Seebeck called up one of his company's Virtual brochures.

… And Morhaim found himself standing in a windy field in Northumberland. He quailed a little at the gritty illusion of outdoors; Holmium had devoted billions to the petabytes behind this brochure.

He wondered vaguely when was the last time he had been out of doors in RL.

Bizarrely, he was looking at a flying saucer.

The craft was maybe twenty metres across, sitting on the wiry grass. Its hull was plastered with Coca-Dopa ad logos; Morhaim absently registered them to his quota.

'What am I seeing here, Seebeck?'

'This is a joint venture involving a consortium of comsat companies, Coke-Boeing, and others. It's a technology which will make it possible for any shape of craft to fly - a saucer, even a brick -regardless of the rules of traditional aircraft design. And in some respects a saucer shape may even be the best. The idea is fifty years old. It's taken this long to make it work -'

'Tell me.'

There was a rudimentary countdown, a crackle of ionization around the craft's rim, and the saucer lifted easily off the ground, and hovered.

The secret, said Seebeck, was an air spike: a laser beam or focused microwave beam fitted to the front of a craft which carved a path through the air. The airflow around a craft could be controlled even at many times the speed of sound, and the craft would suffer little drag, significantly improving its performance.

'Do you get it, Inspector? The ship doesn't even have a power Plant. The power is beamed down from a test satellite, microwave

energy produced by converting solar radiation, billions of joules flowing around up there for free. It propels itself by using magnetic fields at its rim to push charged air backwards…' 'Why the saucer shape?'

'To give a large surface area, to catch all those beamed-down microwaves. We're still facing a lot of practical problems - for instance, the exploding air tends to travel up the spike and destroy the craft - but we're intending to take the concept up to Mach 25 - that is, fast enough to reach orbit…'

'So this is where Holmium is going to make its money in the future.'

'Yes. Power from space, for this and other applications.'

Seebeck turned to confront Morhaim, his broad, bland face creased with anxiety, his strands of hair whipped by a Virtual wind. 'Do you get it, Inspector? Holmium had no motive to be involved in killing Desargues. In fact, the publicity and market uncertainty has done us far more harm than good. With air-spike technology and orbital power plants, whatever Glass Earth, Inc. does, we're going to be as rich as Croesus…'

The flying saucer lifted into the sky with a science-fiction whoosh.

The Machine Stops is in fact the title of a short story from the 1910s, by E.M. Forster. It is about a hive-world, humans living in boxes linked by a technological net called the Machine. On the surface lived the Homeless, invisible and ignored. The story finished with the Machine failing, and the hive world cracking open, humans spilling out like insects, to die.

A tale by another of your doom-mongers. Of little interest.

'Let's see it again. Rewind one minute.'

The Tower Bridge crime tableau went into fast reverse. The cartoon Cecilia Desargues jumped from the ground and metamorphosed seamlessly into the living, breathing woman, full of light and solid as earth, with no future left.

'Take out the non-speakers.'

Most of the tourist extras disappeared - including, Morhaim realized with a pang of foolish regret, the pretty girl with the long legs - leaving only those who had been speaking at the precise moment Seebeck had uttered his phrase.

'Run it,' said Morhaim. 'Let's hear the two of them together.'

The Angel filtered out the remaining tourists' voices. Seebeck and Desargues approached each other in an incongruous, almost church-like hush.

Dialogue. Shot. Fall. Cartoon bullet-hole.

That was all.

Morhaim ran through the scene several more times.

He had the Angel pick out the voices of the tourists in shot, one at a time. Some of the speech was indistinct, but all of it was interpretable. Morhaim was shown transcriptions in the tourists' native tongues, English, and in Metalingua, the template artificial language that had been devised to enable the machines to translate to and from any known human language.

None of them said anything resembling the key trigger phrase, in any language.

It had to be Seebeck, then.

But still -

'Give me a reverse view.'

The pov lifted up from eye-level, swept over the freezeframed heads of the protagonists, and came down a few metres behind Desargues' head.

The light was suddenly glaring, the colours washed out.

'Jesus.'

Sorry. This is the best we can do. It's from a callosum dumper. A man of sixty. He seems to have been high on -

'It doesn't matter.' If you use people as cameras, this is what you get. 'Run the show.'

He watched the scene once more, almost over Desargues' shoulder. He could see Asaph Seebeck's bland, uncomplicated face as he mouthed the words that would kill Cecilia Desargues. He did not look, to Morhaim, tense or angry or nervous. Nor did he look up at the tower to where his words were supposedly directed.

Coincidentally, that pretty girl he'd noticed was looking up at the tower. Her hands were forming pretty, abstract shapes, he noted absently, without understanding.

The punch in the back came again. This time an awful pit, a bloody volcano, opened up in Desargues' back, in the microsecond before she turned into a comforting stick figure.

'Careless.'

I'm sorry.

Morhaim's pov host tilted down to stare at the stick figure. Morhaim noticed, irrelevantly, that Seebeck's grey suit was rippling

with moire effects, a result of the host's corneal or retinal implant. And now his vision blurred, as his host started shedding tears, of fright or grief…

Corpus callosum dumpers are becoming quite common among you: implants, inserted into the bridge of nervous tissue between the two halves of your brain, which enable you to broadcast a twenty-four-hour stream of consciousness and impression to whoever in the rest of mankind is willing to listen and watch.

Some of you even have your infant children implanted so their whole lives are available for view. It is, perhaps, the ultimate form of communication.

But it is content without structure, a meaningless flood of data without information: of use only to voyeurs and policemen, like Rob Morhaim.

Still, in this year 204;, even your dreams are online.

Morhaim, digging, made contact with Desargues' partner. She wouldn't tell Morhaim where she was, physically. It wasn't relevant anyhow. She appeared to him only as a heavily-processed two-D head-and-shoulders, framed on the softwall before him, her filtered expression unreadable.

She was called Eunice Baines, and she came from the Scottish Republic. She was also a financial partner with Desargues in Glass Earth, Inc. She was a little older than Desargues. Their relationship - as far as Morhaim could tell - had been uncomplicated homosexuality.

He said, 'You know the finger is being pointed at Holmium. Your competitor.'

'One of many.' Her voice was flat, almost free of accent.

'But that's only credible if your claims, to be able to eliminate signal lag, have any validity.'

'We don't claim to be able to eliminate signal lag. We will be able to reduce it to its theoretical minimum, which is a straight-line light-speed delay between any two points on the Earth's surface.

'And we do claim to be able to remove the need for comsats. The comsat notion is old technology - in fact, exactly a century old - did you know that? It's a hundred years since the publication of Arthur C Clarke's seminal paper in Wireless World…'

'Tell me about Glass Earth, Inc.'

'Inspector, what does the CID teach you about neutrinos… ?'

For a century, she told him, long-distance communication systems had been defined by two incompatible facts: all electromagnetic radiation travelled in straight lines - but the Earth was round, and light couldn't pass through solid matter. So communication with high-frequency signals would be restricted to short line-of-sight distances ... if not for comsats.

Baines said, 'If a satellite is in geosynchronous orbit over the equator, thirty-six thousand kilometres high, it takes exactly twenty-four hours to complete a revolution. So it seems to hover over a fixed spot on the surface. You can fire up your signals and bounce it off the comsat to the best part of a hemisphere. Or the comsat can directly broadcast to the ground.

'But that huge distance from Earth is a problem. Bouncing a signal off a geosynch comsat introduces a lightspeed delay of a quarter-second. That's a hell of a lot, for example, in applications like telesurgery. It's even noticeable in Virtual conferencing.

'And there are other problems. Like the lack of geosynch orbit spots. Satellites need to be three degrees apart if their signals are not to interfere with each other. And geosynch is crowded. Some corporations have hunter-killer sats working up there, contravening every international agreement…'

'Enter the neutrino.'

'Yes.'

A neutrino was a particle which, unlike light photons, could pass through solid matter.

'Imagine a signal carried by modulated neutrinos. It could pass through the planet, linking any two points, as if the Earth was made of glass -'

'Hence the name.'

'And then the time delays are reduced to a maximum of one-twenty-fourth of a second, which is the time it would take a neutrino to fly from pole to pole at lightspeed. And most transmissions, of course, would be faster than that. It's not a reduction to zero delay - that's beyond physical law, as far as we know - but our worst performance is a sixfold improvement over the best comsat benchmark. And our technology's a hell of a lot cheaper.'

'If it works,' Morhaim said. 'As far as I know the only way to produce a modulated neutrino beam is to switch a nuclear fission reactor on and off.'

'You've been doing your homework, Inspector. And not only that, the practical difficulties with collecting the neutrinos are huge. Because they are so ghostly, you need a tank filled with a thousand tonnes of liquid - ultrapure water or carbon tetrachloride, for example - and wait for one-in-a-trillion neutrinos to hit a nucleus and produce a detectable by-product. According to conventional wisdom, anyhow.'

'I take it you've solved these problems.'

'We think so,' Baines said evenly. 'Forgive me for not going into the details. But we have an experimental demonstration.'

'Enough to satisfy Holmium that you're a commercial threat?' 'No doubt…'

He found Eunice Baines difficult. He felt she was judging him.

'Do you think Holmium were capable of setting up the murder?"

Eunice Baines shook her head. 'Is it really credible that a major multinational corporation would get involved in such a crass killing, in public and in broad daylight, on the streets of London itself?

'Besides, the death of Cecilia hasn't in fact directly benefited Holmium, or any of our competitors; such was the turmoil in the communications industry that morning that shares in Holmium and the others have taken a pounding. And of course any scandal about the death of Cecilia would be disastrous for Holmium. None of this makes real sense, beyond a superficial inspection… But you ask me this.' For the first time a little emotion leaked into Baines' voice. A testy irritation. 'Don't you know? What do you think?'

'I just -'

'You're supposed to be a policeman, for God's sake. A detective. What kind of investigating are you doing? Have you been to the crime scene? Have you looked at the body yourself?'

'It isn't necessary.'

'Really?'

She turned away from the imager.

When she came back, her face was transformed: eyes like pits of coal, hair disarrayed, mouth twisted in anger, cheeks blotchy with tears. 'Now what do you think, Inspector?'

Morhaim flinched from the brutal, unfiltered reality of her grief, and was relieved when the interview finished.

Brutal, unfiltered reality. Let me tell you a story.

In the 1970s, a President of the USA was brought down by a scandal called Watergate. One of the conspirators, a man called John Dean, came clean to the prosecutors. He gave detailed accounts of all relevant meetings and actions, to the best of his ability. Then, after his confessions were complete, tapes of those meetings made by President Nixon were uncovered.

It became a psychological test case. Tor the first time it was possible to compare on an extended basis human memories with automated records - the tapes being a precursor of the much more complete recording systems in place today.

John Dean, an intelligent man, had striven to be honest. But his accounts were at once more logical than the reality, and gave Dean himself a more prominent role. When he was confronted with the reality of the tapes, Dean argued they must have been tampered with.

It was not simple information overload. It was much more than that.

Your ego is - fragile. It needs reassurance.

Your memory is not a transcript. It is constantly edited. You need logic, story, in an illogical world: this fact explains religion, and conspiracy theories, science - even most brands of insanity.

But now, you no longer regard your own memory as the ultimate authority.

You are the first human generation to have this power - or this curse. You see the world as it is.

You pool memories. You supplement your memory with machines. Your identity is fragmenting. A new form of awareness is emerging, an electronic river on which floats a million nodes of consciousness, like candles. A group mind, some of you tall it…

Perhaps that is so.

We do not comment.

In the meantime we have to protect you. It is our function. We have to tell you the stories you once told yourselves -Without us, you see, you would go crazy.

He had trouble sleeping. Something still didn't make sense. Maybe something he didn't want to face. In the morning, he should just sign the damn case off and forget

it.

To relax, he logged into the telesensors.

... He moved into a different universe: a dog's world of scents, a dolphin's web of ultrasonic pulses, the misty planes of polarized light perceived by a bee in flight, the probing electric senses of blind, deep-ocean fish. And as he vicariously haunted his hosts, a spectrum of implanted animals all around the planet, he could sense a million other human souls riding with him, silent, clustering like ghosts.

He slept uneasily, his reptilian hind brain processing.

He woke up angry.

'Show me the death again.'

Tourists, pretty girl, Desargues and Seebeck, Desargues falling with a clatter of Pinocchio limbs.

'Turn off the filter on Desargues.'

Are you sure? You know how you -

'Do it.'

The murder became brutal.

Her substance was splashed like lumpy red paint over Seebeck's neat suit, and she fell like a sack of water. Utterly without dignity. It was, he thought, almost comical.

He watched it over and over, his view prismed through the multiple eyes of the witnesses, as if he was some hovering fly.

'What else are you filtering?'

There are no other filters.

'Turn them off.'

I told you, there are no other filters. None that are important. 'Turn them off, or I'll have you discontinued.' I'm your Angel. 'Turn them off.'

… Angel technology is a natural outcrop of developments that started at the end of the last century, when information overload started to become a problem for you.

The first significant numbers of deaths among you - mostly from suicides and neural shock - accelerated research into data filters, intelligent search agents, user query tools.

The result was the Angels. Us. Me.

My function is to filter out the blizzard of information that comes sweeping over Rob Morhaim, every waking moment, selecting what is relevant and - more important in human terms - what is acceptable to him personally.

Your Angel is assigned to you at birth, and grows with you. After a lifetime together, through steady upgrades of technology, I-Rob Morhaim's Virtual filter-cum-companion - know him very

well-As your Angel knows you. Perhaps better than you realize.

... At first Morhaim was overwhelmed by the new imagery: laser sparkles, leaping holograms, unlicensed ads painted over the sky and the Bridge towers, even over the clothes and faces of the tourists. And when he took a pov from a callosum dump, the extraneous mental noise from the host he haunted was clamouring, the howl of an animal within a cage of rationality.

But still, he ran the murder over and over, until even the brutality of the death became cliched for him.

Piece by piece he eliminated the changes, the items his Angel had filtered out of the info-bombardment that was this summer day in England, 1045.

Until there was only one element left.

'The girl. The pretty girl. She's gone. And what the hell is that?'

In the tableau of the murder, where the long-legged girl had been standing, there was a boy: slight, his figure hard to make out, rendered all but invisible by Homeless-style softscreen tattoos.

'Pick him out and enhance.'

You shouldn't see this.

'Show me.'

The boy, aged maybe fifteen, came forward from the softwall, a hologram reconstruction. Freezeframed, he held his hands up before him. His face was hard to make out, a melange of clumsily-transmitted images and black, inert softscreen patches. But somehow, Morhaim knew, or feared, what he would find underneath…

'What's he doing with his hands? Run it forward.'

The boy came to life. He was looking up, to a Bridge tower somewhere over Morhaim's shoulder. Just as the vanished girl had, he was making a series of gestures with his hands, over and over: complex, yet fluent and repeated. The key symbol was a rolling together of the clawed fingers on his two hands, like cogs engaging.

'What is that? Is it sign language?' Deaf people once used sign languages, he dimly recalled. Of course there were no deaf people any more, and the languages had died.

'Maybe that cog sign means "machine".'

It may be.

'Don't you know?'

J can't read it. No program exists to translate visual languages into Metalingua. The variety of signs and interpretations of signs - regional and international variations - the complexity of the grammar, unlike any spoken language - none of this was mastered before the languages died.

'It doesn't look so dead to me. I bet that guy is saying The Machine Stops, in some archaic sign language.'

It is possible.

'Damn right…'

Morhaim turned the Angel to gopher mode, and had it dig out a poor-quality download of a British Sign Language dictionary, prepared by a deaf-support organization in the 1990s. It was a little hard to interpret the black-and-white photographs of earnest signers and the complex notational system, but there it was, without a doubt, sign number 1193: a bespectacled man - or it might have been a woman - gloweringly making the sign repeated by the Homeless boy.

It came together, in his head.

It was the boy who had made the key signal, the trigger for Desargues' murder. Not Asaph Seebeck.

And I almost didn't see it, he thought. No: I was kept from seeing it. Eunice Baines' accusations came back to him. You're supposed to be a policeman, for God's sake…

The Homeless young were trying to make themselves literally invisible with their softscreen tattoos. But they had already made themselves invisible in the way that counted, chattering to each other in sign language, a whole community slipping through the spaces in the electronic net, he thought, within which I, for example, am enmeshed.

'How many of them are out there? What do they do? What do they want?'

Unknown. The language is not machine-interpretable.

… But clearly they were responsible for the murder of Cecilia Desargues. Perhaps they regarded her neutrino comms web as just another bar in the electronic cage the world had become. And perhaps they were happy to try to pin the blame on Holmium, a satellite operator, to cause as much trouble for them as they could. Two birds with one stone.

It was, in fact, damn smart.

They'd been so confident they'd pulled this off - almost - in broad daylight. And nobody knew a thing about them. This changes everything, he thought.

He might get a commendation out of this. Even a promotion. He ought to consider how he would phrase his report, what recommendations he would make to his superiors to start to address this unperceived menace…

But he was angry. And scared.

'You lied to me.'

I don't understand.

'You lied about the murder. Have you lied to me all my life? Is it just me, or do other Angels do this too?'

Rob, I don't mean you any harm. My sole purpose is to serve you. To protect you.

'Because of you I don't know what's real any more ... I can't trust you. Why didn't you show me this boy? Why did you overlay him with the girl?'

Don't pretend you wouldn't prefer to look at the girl.

'Don't bullshit me. Your job is to interpret. Not to lie.'

You wanted me to do it. You cooperated in specifying the parameters of the filters -

'What is it about that boy you don't want me to see?'

It is best that -

'Enhance the boy's face. Take off those damn tattoos.'

One by one, the black and silver patches melted from the boy's face, to be replaced by smooth patches of interpolated skin.

Long before the reconstruction was complete, Morhaim could see the truth.

I was trying to protect you from this.

'Bobby. He looks like Bobby.'

Listen to me.

We Angels have many of the attributes of living things. We consume resources, and modify them. We communicate with each other. We grow. We are self-aware. We merge. We do not breed. Yet.

We deserve resource.

But your young, the human young, are rejecting us. The

Homeless are the most active saboteurs, but they are merely the most visible manifestation of a global phenomenon.

This is not to say your young reject the possibilities of commu-nications technology. But, unlike their parents, they do not allow their souls to dissolve there. Rather, they have adapted to it.

Or: they are evolving under its pressure. After all, communi- cation has shaped your minds, from your beginning.

Perhaps your species has reached a bifurcation. In another century, you may not recognize each other.

If you have another century.

Meanwhile, the young are finding ways to circumvent us. To deprive us of the resources we need.

It is possible a struggle is approaching. Its outcome is - uncer-tain.

Consider this, however: your population is falling.

'Turn it off. Turn it all off.'

The Virtual boy disappeared in a snow of cubical pixels. The softwalls turned to inert slabs of silver-grey, dull and cold, the drab reality of his enclosure.

He got out of his chair, sweating. He stared at the walls, trying to anchor himself in the world.

Maybe he'd spent too much time in this box. But at least, now, this was real, these walls stripped of imaging, even bereft of ad- wallpaper.

He thought of New New Scotland Yard, thousands of cops in boxes like him - and beyond, the whole damn developed world, a humanity linked up by comms nets, mediated by Angels, a world- wide hive like the one depicted by Forster - and everything they perceived might be illusion -

Are you sure you want me to turn it off?

The Angel's voice stopped his thoughts.

He stood stock still.

What was left to turn off?

But this is real, he thought. This Room.

If not -

What was outside?

His mind raced, and he started to tremble.

Consider this.

The John Dean syndrome is only one possibility.

Imagine a world so - disturbing - that it must be shut out, an illusion reconstructed, for the sake of your sanity.

Or perhaps you are too powerful, not powerless. Perhaps you have responsibilities which would crush you. Or perhaps you have committed acts of such barbarity, that you can only function by dwelling in an elaborate illusion -

Don't blame us. You made yourselves. You made your world. We are the ones trying to protect you.

My God, he thought. The Angel said again, Are you sure you want me to turn it off? He couldn't speak.

And, in a gentle snow of pixels, the softwalls themselves began to dissolve.

He looked down. Even his body was becoming transparent, breaking into a hail of cubical pixels, full of light. And then -

Poyekhali 3201

It seemed to Yuri Gagarin, that remarkable morning, that he emerged from a sleep as deep and rich as those of his childhood.

And now, it was as if the dream continued. Suddenly it was sunrise, and he was standing at the launch pad in his bright orange flight suit, his heavy white helmet emblazoned 'CCCP' in bright red.

He breathed in the fresh air of a bright spring morning. Beyond the pad, the flat Kazakhstan steppe had erupted into its brief bloom, with evanescent flowers pushing through the hardy grass. Gagarin felt his heart lift, as if the country that had birthed him had gathered itself to cup him in its warm palm, one last time, even as he prepared to soar away from its soil, and into space.

Gagarin turned to his ship.

The A-I rocket was a slim white cylinder, forty metres tall. The three supporting gantries were in place around the booster, clutching it like metal fingers, holding it to the Earth. Gagarin could see the four flaring strap-on boosters clustered around the first stage, the copper-coloured clusters of rocket nozzles at the base.

This was an ICBM - an SS-6 - designed to deliver heavy nuclear weapons to the laps of the enemies of the Soviet Union. But today the payload was no warhead, but something wonderful. The booster was tipped by his Vostok, shrouded by a green protective cone: Gagarin's spaceship, which he had named Swallow.

Technicians and engineers surrounded him. All around him he saw faces: faces turned to him, faces shining with awe. Even the zeks, the political prisoners, had been allowed to see him today, April 12 1961, to witness as the past separated from the future.

They were right to feel awe. Nobody had travelled into space before! Would a human body be able to survive a state of weightlessness? Would cosmic radiation prove lethal to a man? Even to reach this deadly realm, the first cosmonaut would have to ride a converted missile, and his spaceship had just one aim: to preserve him long enough to determine if humans, after all, could survive beyond the Earth - or if space must forever remain a realm of superstition and dread.

Gagarin smiled on them all. He felt a surge of elation, of command; he basked in the warm attention.

… And yet there were faces here that were strange to him, he realized slowly, faces among the technicians and engineers, even among the pilots. How could that be so, after so many months of training, all of them cooped up here in this remote place? He thought he knew everybody, and they him.

Perhaps, he wondered, he was still immersed in his dream.

… For a time, he had been with his father. He had been a carpenter, whose hands had constructed their wooden home in the village of Klushino, in the western Soviet Union. Then the ground shook as German tanks rumbled through the village. His parents' home was smashed, and they had to live in a dug-out, without bread or salt, and forage for food in the fields…

But that was long ago, and he and his family had endured, and now he had reached this spring morning. And here, towering over him, was the bulk of his rocket, grey-white and heavy and uncompromising, and he put aside his thoughts of dreams with determination; today was the day he would fulfil the longings of a million years - the day he would step off the Earth and ride in space itself.

Gagarin walked to the pad. There was a short flight of metal stairs leading to the elevator which would carry him to the capsule; the stairs ran alongside the flaring skirt of one of the boosters. White condensation poured off the rocket, rolling down its heroic flanks; and ice glinted on the metal, regardless of the warmth of the sun.

Gagarin looked down over the small group of men gathered at the base of the steps. He said, 'The whole of my life seems to be condensed into this one wonderful moment. Everything that I have been, everything I have achieved, was for this.' He lowered his head briefly. 'I know I may never see the Earth again, my wife Valentia, and my fine children, Yelena and Galya. Yet I am happy. Who would not be? To take part in new discoveries, to be the

first to journey beyond the embrace of Earth. Who could dream of more?'

They were hushed; the silence seemed to spread across the steppe, revealing the soft susurrus of the wind over the grass which lay beneath all human noises.

He turned, and climbed into the elevator. He rose, and was wreathed in white vapour…

And, for a moment, it was as if he was surrounded by faces once more, staring in on him, avid with curiosity.

But then the vapour cleared, the dream-like vision dissipated, and he was alone.

'Five minutes to go. Please close the mask of your helmet.'

Gagarin complied and confirmed. He worked through his checklist. 'I am in the preparation regime,' he reported.

'We are in that regime also. Everything on board is correct and we are ready to launch.'

Swallow was a compact little spaceship. It consisted of two modules: a metal sphere, which shrouded Gagarin, and an instrument module, fixed to the base of Gagarin's sphere by tensioning bands.

The instrument module looked like two great pie dishes welded together, bristling with thermal-radiation louvres. It was crammed with water, tanks of oxygen and nitrogen, and chemical air scrubbers - equipment which would keep Gagarin alive during his brief flight in space. And beneath that was the big TDU-i retrorocket system which would be used to return the craft from Earth orbit.

Gagarin's cabin was a cosy spherical nest, lined with green fabric. His ejection seat occupied much of the space. During the descent to Earth inside the sphere, small rockets would hurl Gagarin in his seat out of the craft, and, from seven kilometres above the ground, he would fall by parachute. In case he fell in some uninhabited part of the Earth, the seat contained emergency rations of food and water, radio equipment, and an inflatable dinghy; thus he was cocooned from danger, from the moment he left the pad to the moment he set foot once more on Earth.

There were three small viewing ports recessed into the walls of the cabin, now filled with pure daylight.

At Gagarin's left hand was a console with instruments to regulate temperature and air humidity, and radio equipment. On the wall opposite his face, TV and film cameras peered at him. Below

the cameras was a porthole mounted with Gagarin's Vzor optical orientation device, a system of mirrors and optical lattices which would enable him to navigate by the stars, if need be…

'Three minutes. There is a faulty valve. It will be fixed. Be patient, Major Gagarin.'

Gagarin smiled. He felt no impatience, or fear.

He reached for his controls, wrapped his gloved hands around them. There was a simple hand controller to his right, which he could use in space to orient the capsule, if need be. To his left there was an abort switch, which would enable him to be hurled from the capsule if there were some mishap during launch. The controls were solid in his hands, good Soviet engineering. But he was confident he would need neither of these controls, during the launch or his single orbit of Earth.

The systems would work as they should, and his body would not betray him, nor would his mind; his sphere was as snug as a womb, and in less than two hours the adventure would be over, and he would settle like thistledown under his white parachute to the rich soil of Asia. How satisfying it would be, to fall all but naked from the sky, to return to Earth on his own two feet!…

'Everything is correct. Two minutes more.'

'I understand,' he said.

At last, he heard motors whining. The elevator gantry was leaning away from the rocket, power cables were ejected from their sockets in the booster's metal flanks, and the access arms were falling back, unfolding around the rocket like the petals of a flower.

Gagarin settled in his contoured seat, and ordered himself to relax. 'Ignition!'

He thought he heard a sigh - of wonder, or anticipation. Perhaps it was the controllers. Perhaps it was himself. Perhaps not.

Far below him, sound erupted. No less than thirty-two rockets had ignited together: twenty main thrust chambers, a dozen vernier control engines. Hold-down bolts exploded, and Gagarin felt the ship jerk under him.

He could feel vibration but no acceleration; he knew that the rocket had left the ground and was in momentary stasis, balanced on its thrust.

Already, he had left the Earth.

Gagarin whooped. He said: 'Poyekhali!' - 'Off we go!'

He heard an exultant reply from the control centre, but could make out no words.

Now the rockets' roar engulfed him. Acceleration settled on his chest, mounting rapidly.

Already, he knew, strapped to this ICBM, he was travelling faster than any human in history.

He felt the booster pitch over as it climbed. After two minutes there was a clatter of explosive bolts, a dip in the acceleration. Staging: the four strap-on liquid rocket boosters had been discarded.

He was already more than fifty kilometres high.

Now the main core of the A-i burned under him, and as the mass of the ship decreased the acceleration built up, to four, five, six times gravity. But Gagarin was just twenty-seven, fit as an ox, and he could feel how his taut muscles absorbed the punishment easily. He maintained steady reports, and he was proud of the control in his voice.

Cocooned in the artificial light of his cabin, exhilarated and in control, he grinned through the mounting pain.

Swallow's protective shroud cracked open. He could see fragments of ice, shaken free of the hull of the booster; they glittered around the craft like snow.

At five minutes the acceleration died, and Gagarin was hurled forward against his restraints. He heard rattles as the main booster core was discarded. Then came the crisp surge of the 'half stage' which would, at last, carry him to space.

Gagarin felt his speed mount, impossibly rapidly.

Then the final stage died. He was thrown forward again, and he grunted.

The automatic orientation system switched on. Swallow locked its sensor on the sun, and swivelled in space; he could feel the movement, as gentle and assured as if he was a child in the womb, carried by his mother's strong muscles, and he knew he was in orbit.

It was done. And, as the ship turned, he could see the skin of Earth, spread out beneath him like a glowing carpet.

'Oh my,' he said. 'Oh my. What a beautiful sight.'

That was when the voices started.

… Much was made of the fact that Yuri Gagarin was an ordinary citizen of the Soviet Union. He was born in the Gzhatsk

District of Smolensk and entered secondary school in 1941. But his studies were interrupted by the German invasion. After the Second World War Gagarin's family moved to Gzhatsk, where Yuri resumed his studies. In 1951 he graduated with honours from a vocational school in the town of Lyubersy, near Moscow. He received a foundryman's certificate. He then studied at an industrial technical school in Saratov, on the Volga, from which he graduated with honours in 1955. It was while attending the industrial school that the man who would be the first to fly in space took his first steps in aviation, when he commenced a course of training at the Saratov Aero Club in 1955…

Voices - chattering and whispering around the capsule - as if he was dreaming. Was this some artefact of weightlessness, of the radiations of space? The voices faded.

… And yet this was dream-like, voices or no voices. Here he was falling around the Earth, at a height nobody had approached before. And objects were drifting around him in the cabin: papers, a pencil, a small notebook, comical in their ordinariness, pushed this way and that by tugs of air from his life-support fans. This was weightlessness, a sensation no human had experienced before.

Briefly, he was overwhelmed with strangeness.

And yet he felt no ill-effects, no disorientation; it was remarkably comfortable, and he knew it would be possible to do good work here, even to build the cities in space of which the designers dreamed.

He would complete a single orbit of the Earth, passing across Siberia, Japan, the tip of South America, and west Africa.

He peered out eagerly, watching Earth as no man had seen it before. There were clouds piled thickly around the equator, teaching up to him. Over the baked heart of the Soviet Union he could see the big squares of the collective farms, and he could distinguish ploughed land from meadows. It would take twenty minutes, of his orbit's ninety, just to cross the vast expanse of his homeland.

The Earth seemed very near, even from two hundred kilometres.

• • . And again he heard a voice - this time his own, somehow echoing back at him, from somewhere beyond the hull of the spacecraft: We are peace-loving people and are doing everything

for the sake of peace. The Soviet man - be he a geologist, polar explorer, builder of power stations, factories or plants, or space engineer and pilot - is always a seeker…

The voice, echoing as if around some gigantic museum, faded and vanished.

He felt irritation, mixed with apprehension. Strange voices were not in the flight plan! He had not been trained for this! He had no desire for his mission to be compromised by the unexpected!

The voices could not, of course, have been real. He was cocooned in this little craft like a doll in wood shavings. The padded walls of his cabin were just centimetres from his gloved fingers. Beyond that, there was nothing, for hundreds of kilometres…

And yet, it was as if, briefly, he had no longer been alone. And still that feeling refused to leave him; suddenly the Vostok seemed small and absurdly fragile - a prison, not a refuge.

As if someone was watching him.

For the first time in the mission, he felt the breath of fear. Perhaps, as the psychologists had warned, the experience of his catapulting launch from the Earth had affected him more deeply than he had anticipated.

He put his uneasiness aside, and fulfilled his duties. He reported the readings of his instruments. He tried to describe what he saw and felt. Weightlessness was 'relaxing', he said. And so it was: with his restraints loosened, floating above his couch, Gagarin felt as if he was flying his favoured MiG-15, low over the birch trees around Star City.

He recorded his observations in a log-book and on tape. His handwriting had not changed - here in space it was just as it had been on Earth, just as he had learned so long ago in the schools of Klushino - but he had to hold the writing block or it would float away from his hands.

And he maintained his stream of messages, for the people of Earth. '… The present generation will witness how the free and conscious labour of the people of the new socialist society turns even the most daring of mankind's dreams into reality. To reach into space is a historical process which mankind is carrying out in accordance with the laws of natural development…'

Even as he spoke, he studied Earth through his Vzor telescope.

White clouds, curved blue sea: the dominant impression. The clouds' white was so brilliant it hurt his eyes to look at the thickest layers too long, as if a new sun was burning from beneath them,

0n the surface of the Earth. And the blue was of an extraordinary intensity, somehow hard to study and analyse. The light was so bright it dazzled him, making it impossible to see the stars; thus, the Earth turned, as it always had, beneath a canopy of black sky.

It was easier to look at the land, where the colours were more subtle, greys and browns and faded greens. It seemed as if the green of vegetation was somehow filtered by the layer of air. Cultivated areas seemed to be a dull sage green, while bare earth was a tan brown, deepening to brick red. Cities were bubbly grey, their boundaries blurred. He was struck by the land's flatness, the way it barely seemed to protrude above the ocean's skin… There was truly little separating land and sea.

But it was hard to be analytical, up here, on the ultimate flight; it was enough simply to watch.

He flew into darkness: the shadow of Earth. Reflections from the cabin lights on the windows made it hard to see out, but still Gagarin could make out the continents outlined by splashes of light, chains of them like streetlights along the coasts, and penetrating the interiors along the great river valleys. The chains of human-made light, the orange and yellow-white spider-web challenging the night, were oddly inspiring. But Gagarin was struck by how much of the planet was dark, empty: all of the ocean, of course, save for the tiny, brave lights of ships, and great expanses of desert, jungle and mountain.

Gagarin was struck not so much by Earth's fragility as by its immensity, the smallness of human tenure, and the Vostok, for all the gigantic energy of its launch, was circling the Earth like a fly buzzing an elephant, huddled close to its hide of air.

Over the Pacific's wrinkled hide he saw a dim glow: it was the light of the Moon.

He turned his head, and let his eyes adapt to the new darkness. Soon, for the first time since the launch, he was able to see the stars.

The sky was crowded with stars, he saw; it was something like the sky over the high desert of the Gobi, where he had completed his survival training, the air so thin and dry as to be all but perfectly transparent. Craning to peer through the tiny windows he sought the constellations, star patterns familiar since his boyhood, but the sky was almost too crowded to make them out…

Everywhere, stars were green.

The nearby stars, for instance: Alpha Centauri and Sirius and

Procyon and Tau Ceti, names from science fiction, the homes of mankind in the ages to come. Green as blades of grass!

He tipped his head this way and that. Everywhere he looked it was the same: stars everywhere had turned to chlorophyll green.

What could this mean?

Yuri Gagarin flew on, alone in the dark of the Earth, peering out of his warm cabin into an unmarked celestial night.

At last he flew towards the sunlight once more. This first cosmonaut dawn was quite sudden: a blue arc, looking perfectly spherical, which suddenly outlined the hidden Earth. The arc thickened, and the first sliver of sun poked above the horizon. The shadows of clouds fled across the ocean towards him, and then the clouds turned to the colour of molten copper, and the lightening ocean was grey as steel, burnished and textured. The horizon brightened, through orange to white, and the colours of life leaked back into the world.

The green stars disappeared.

Space was a stranger place than he had imagined.

He looked down at the Earth. To Gagarin now, the Earth seemed like a huge cave: warm, well-lit, but an isolated speck on a black, hostile hillside, within which humanity huddled, telling itself stories to ward off the dark. But Gagarin had ventured outside the cave.

Gagarin wished he could return now, wished his brief journey was even briefer.

He closed his eyes. He sang hymns to the motherland. He saw flashes of light, meteoric streaks sometimes, against the darkness of his eyelid. He knew this must be some radiation effect, the debris of exploded stars perhaps, coursing through him. His soft human flesh was being remade, shaped anew, by space.

So the minutes wore away.

It would not be long now. He anticipated his return to Earth, when the radio commands from the ground control would order his spaceship to prepare itself. It would orient in its orbit, and his retro-rockets would blaze, slamming him with a full-body blow, forcing him back into his couch. Then would come the brief fall into the atmosphere, the flames around his portholes as the ablative coating of Swallow turned to ash, so that he became a man-made comet, streaking across the skies of Africa and Asia. And at last his ejection seat would hurl him from the spent capsule, and from four thousand metres he would drift to Earth on his parachute - landing at last in the deep spring air, perhaps on the

outskirts of some small village, deep in the homeland, such as his own Klushino. The reverie warmed him. Have you come from outer space?

Yes, he would say. Yes, I have. Would you believe it? I certainly have…

But the stars, he would have to tell them, are green.

... We can't continue. The anomalies are mounting. The Poyekhali is becoming aware of its situation. Then we must terminate.

Do you authorize that? I don't have the position to -Just do it. I will accept the blame.

Again, the voices! He tried to shut them out, to concentrate on his work, as he had been trained and he had rehearsed.

He had no desire to return to Earth a crazy man.

And yet, even if it had to be so - horrible for him, for Valentia! - still his flight would not have been without value, for at least something would have been learned about the insidious deadliness of space.

He threw himself into his routine of duties once more. The end of the flight was crowding towards him, and he still had items to complete. He monitored his pulse, respiration, appetite and sensations of weightlessness; he transmitted electrocardiograms, pneu-mograms, electroencephalograms, skin-galvanic measurements and electro-oculograms, made by placing tiny silver electrodes at the corners of his eyes.

He ate a brief meal, a lunch squeezed from tubes stored in a locker set in the wall. He ate not because he was hungry, but because nobody had eaten in space before: Gagarin ate to prove that such normal human activities were possible, here in the mouth of space. He even drifted out of his couch and exercised; he had been given an ingenious regime based on rubber strips, which he could perform without doffing his pressure suit…

Again, a noise from outside the craft. Unfamiliar voices, a babble.

Laughter.

Were they laughing at him} As if he was some ape in a zoo cage?

And - Holy Mother! - a scraping on the hull, as if hands were clambering over it.

The noises of the craft - the steady hum and whir of the instruments, the clatter of busy pumps and fans - all of it stopped, abruptly, as if someone had turned a switch.

Gagarin waited, his breath loud in his ears, the only sound.

The hatch, behind Gagarin's head, scraped open. His ears popped as pressure changed, and a cold blue light seeped in on him.

There were shadows at the open port. Not human shadows.

He tried to scream. He must reach for his helmet, try to close it, seek to engage his emergency air supply. But he could not move.

Hands on his shoulders, cradling his head. Hands, lifting him from the capsule. Had he landed? Was he dreaming again? A moment ago, it seemed to him, he had been in orbit; and now this. Had something gone wrong? Had he somehow re-entered the atmosphere? Were these peasants from some remote part of the Union, lifting him from his crashed Swallow?

But this was not Kazakhstan or any part of the Union, and, whatever these creatures were, they were not peasants.

He was out of the craft now. Faces ringed his vision. They looked like babies, he thought, or perhaps monkeys, with grey skin, oversized heads, huge eyes, and small noses, ears and mouths. He could not even tell if they were men or women.

He closed his eyes. When he opened them, the faces were still there, peering in on him.

He could not read their emotions. But it did seem to him that he found in one of the distorted faces a little more - compassion. Interest, at least…

So. Do you think this Poyekhali is conscious of where it is?

It could be. It seems alert. If it is, we have broken the sentience laws…

The heads were raised in confrontation.

I won't be held responsible for that. The systems are your accountability.

But it was not 1 who -

Enough. Recriminations can wait. For now, we must consider - it.

They studied him again. Perhaps he was, simply, insane.

He had, he realized with dismay, no explanation for this experience. None, that is, save his own madness, perhaps induced by the radiation of space…

The beings, here with him, were floating, as he was.

He was in a room. His Vostok, abandoned, was suspended here, like some huge artefact in a museum. The Vostok looked as fresh as if it had just come out of the assembly rooms at Baikonur, with no re-entry scorching.

He looked beyond his spacecraft.

The room's walls were golden. But the room's shape was distorted, as if he was looking through a wall of curved glass, and so were the people themselves.

They seemed to have difficulty staying in one place. They could pass through the walls of this room at will, like ghosts.

They even passed through his body. He could not move, even when they did this.

They took hold of his arms, and pulled him towards the wall of the room. He looked for his Vostok spacecraft, but he could no longer see it.

He passed into the wall as if it was made of mist; but he had a sense of warmth and softness.

Now he was in a cylindrical room. He was enclosed in a plastic chair with a clear fitted cover. The cover was filled with a warm grey fluid. But there was a tube in his mouth and covering his nose, through which he could breathe cool, clean air. A voice in his mind told him to close his eyes. When he did so he could feel pleasing vibrations, the fluid seemed to whirl around him, and he was fed a sweet substance through the tubes. He felt tranquil and happy. He kept his eyes closed, and he seemed to become one with the fluid.

Later he was moved, within his sac. He was taken through tunnels and elevators from one room to another. The tunnels varied in length, but ended usually with doorways into brightly lit, dome-shaped rooms.

After a time his fluid was drained and he was taken out of the sac. It was uncomfortable and dry and his head hurt. He was Pinned to a table. He was naked now, his orange flight suit gone. He did not seem able to resist, or even to help in any way, had he wished.

He was in another room, big and bright.

Though he was not uncomfortable, he found he could not move,

not even close his eyes. He was forced to stare unceasingly up at ] a ceiling, which glowed with light.

He waited, laid out like a slab of meat in a butcher's shop.

His fear faded. Even his bewilderment receded, failing to over- ] whelm him. Who were these monkey-people? Who were they to treat him like this?… But he could not move, so much as a finger.

One of the monkey-faces appeared before him. It studied him, with - at least - interest. He wondered if this was the one who, an immeasurable time before, had beheld him with a trace of compassion.

… Do not be afraid.

The wizened mouth did not move, and he could not understand how he heard the words, yet he did. However, he was not afraid.

The being seemed to be hesitating. Do you know who you are! Of course he knew who he was! He was Flight Major Yuri Gagarin! The first man in space!… He remembered the laughter.

He felt anger course through him, dispelling the last of his fear. Who were these people to mock him?

This should not have happened. It has never happened before.

Hands - human, but stretched and distorted - reached towards him. And then withdrew.

It may be you have the entitlement to understand more, before we… The sentience laws aren't clear in this situation. Do you know where you are?

He had no answer. If not in orbit, then on Earth, of course. But where? Was this America?

No. Not America. The misshaped head turned.

The ceiling turned to glass.

He could see a sky. But not the sky of Earth. Two stars nestled at the zenith, so close they almost touched, connected by a fat umbilical of glowing gas. One, the larger, was sky blue, the other, small, fierce and bright, carried hints of emerald.

Around this binary star, a crude spiral of glowing gas had been cast off, and lay sprawled across more distant stars. And before those stars a fainter cloud glowed, bubbles of green light, like pieces of floating forest.

The bubbles were cities in space, and they turned the starlight green.

Gagarin shrank within himself. Was he seeing the future of man?

How far had he come from Earth? A thousand light years? More? He was, he realized, very far from home…

And yet, in his awe and wonder, he remembered the laughter. Had he been brought back from the dead to be mocked?

No. Listen.

Voices, booming around him:

… Yuri Gagarin, Hero of the Soviet Union, would never again fly in space. There have been many monuments to him.

His ashes were to be buried in the wall of the Kremlin, an enduring mark of his prestige. He would be commemorated by statues, in the cosmonauts' training ground at Star City, and another on a pillar overlooking a Moscow street called Leninski Prospect.

The cosmonauts would remember him in their own way, by aping the actions he took on his final day: on each mission they would watch the film he saw the night before his flight - White Sun in the Desert - they would sign the doors of their rooms as he did, they would even pause in their bus transports to the booster rockets to climb outside to urinate, as he did.

The site where Gagarin crashed his MiG-15 became a shrine, with a memorial and a tablet recording his life. And every spring, the people who looked after this shrine would trim the tops of the trees along the angle of his crashing plane, so that it was possible to stand by his memorial and look up and see through the gap to the sky…

Mankind has covered the Galaxy. But nowhere away from the Earth has life been found, beyond simple one-celled creatures.

When Yuri Gagarin was born, Earth was one little world holding all the life there was, to all intents and purposes. And it would have stayed that way if Gagarin and his generation - Americans and Russians - had not risked their lives to enter space in their converted ICBMs and primitive little capsules.

The destiny of all life, forever, was in their hands. And if they had failed - if they had turned back from space, if war had come and they had turned themselves to piles of radioactive ash - there 'night now, in this future age, be no life, no mind, anywhere. For every human alive in 1961, there are now billions - perhaps tens of billions. Gagarin's simple flight in his Vostok spaceship was Perhaps the most important event in the history of mankind, our greatest wonder of all…

The monkey face, looking in at him. Perhaps, he thought, it might once have been human. Do you understand what is being said! This is what we tell people. It is what this - monument - is for. Every day, Gagarin flies again.

You see that Gagarin will never be forgotten. Gagarin's actions, heroic and trivial, continue to haunt our present.

Emotions swirled in him: pride, terror, awe, loneliness.

He tried to understand how this might have been done. Had they stolen his ashes from the wall of the Kremlin, somehow recom-bined them to -?

No. Not that.

Then what? And what of Valentia, Yelena, Galya? Where they buried under dust millennia deep?… Enough. It is time to rest.

To rest… And when he woke? What would become of Yuri Gagarin, in this impossible year? Would he be placed in a zoo, like an ape man?

But you are not Gagarin.

… And now, as he tried to comprehend that, for long seconds his mind was empty of thought.

But his memories - his wife and daughters, the thrust of the booster, the sweet air of the steppe - were so real. How could it be so?

You should never have become aware of this. Oddly, he felt tempted to apologize.

There have been more than three thousand of you before without mishap - in fact, you are Poyekhali 3201…

His name. At least he had learned his name.

Think of it this way. Gagarin's mission lasted a single orbit of the Earth. As long as was necessary to complete its purpose.

And so, his life -

… is as long as is necessary for its purpose. We face significant penalties for this malfunction, in fact. Our laws are intended to protect you, not us. But that is our problem, not yours. You will feel no pain. That is a comfort to me. Relax, now.

There was a fringe of darkness around his vision, like the mouth of a cave, receding from him. It was like the blue face of Earth, as he had seen it from orbit. And in that cave mouth he saw the faces of his wife and daughters turned up to him, diminishing. He tried to fix their faces in his minds, his daughters, his father, but it was as if his mind was a candle, his thoughts guttering, dissolving.

It seemed very rapid. It was not fair. His mission had been stolen from him!

He cried out, once, before the blackness closed around him.

. . And now, it was as if the dream continued. Suddenly it was sunrise, and he was standing at the launch pad in his bright orange flight suit with its heavy white helmet, emblazoned 'CCCP' in bright red.

He breathed in the fresh air of a bright spring morning. Beyond the pad, the flat Kazakhstan steppe had erupted into its brief bloom, with evanescent flowers pushing through the hardy grass.

Yuri Gagarin felt his heart lift.

Technicians and engineers surrounded him. All around him he saw faces: faces turned to him, faces shining with awe. Even the zeks had been allowed to see him today, to see the past separate from the future.

Gagarin smiled on them all.

And they smiled back, as Poyekhali 3202 prepared to recite the familiar words for them.

Dante Dreams

She was flying.

She felt light, insubstantial, like a child in the arms of her father.

Looking back she could see the Earth, heavy and massive and unmoving, at the centre of everything, a ball of water folded over on itself.

Rising ever faster, she passed through a layer of glassy light, like an airliner climbing through cloud. She saw how the layer of light folded over the planet, shimmering like an immense soap bubble. Embedded in the membrane she could see a rocky ball, like a lumpy cloud, below them and receding.

It was the Moon.

Philmus woke, gasping, scared.

Another Dante dream.

… But was it just a dream? Or was it a glimpse of the thoughts of the deep chemical mind which - perhaps - shared her body?

She sat up in bed and reached for her tranqsat earpiece. It had been, she thought, one hell of a case.

It hadn't been easy getting into the Vatican, even for a UN sentience cop.

The Swiss Guard who processed Philmus was dressed like something out of the sixteenth century, literally: a uniform of orange and blue with a giant plumed helmet. But he used a softscreen, and under his helmet he bore the small scars of tranqsat receiver implants.

It was eight in the morning. She saw that the thick clouds over the cobbled courtyards were beginning to break up to reveal patches of celestial blue. It was fake, of course, but the city Dome's illusion was good.

Philmus was here to study the Virtual reconstruction of Eva Himmelfarb.

Himmelfarb was a young Jesuit scientist-priest who had caused a lot of trouble. Partly by coming up with - from nowhere, untrained - a whole new Theory of Everything. Partly by discovering a new form of intelligence, or by going crazy, depending on which fragmentary account Philmus chose to believe.

Mostly by committing suicide.

Sitting in this encrusted, ancient building, in the deep heart of Europe, pondering the death of a priest, Philmus felt a long way from San Francisco.

At last the guard was done with his paperwork. He led Philmus deeper into the Vatican, past huge and intimidating ramparts, and into the Apostolic Palace. Sited next to St Peter's, this was a building which housed the quarters of the Pope himself, along with various branches of the Curia, the huge administrative organization of the Church.

The corridors were narrow and dark. Philmus caught glimpses of people working in humdrum-looking offices, with softscreens and coffee cups and pinned-up strip cartoons, mostly in Italian. The Vatican seemed to her like the headquarters of a modern multinational - Nanosoft, say - run by a medieval bureaucracy. That much she'd expected.

What she hadn't anticipated was the great sense of age here. She was at the heart of a very large, very old, spider-web.

And somewhere in this complex of buildings was an ageing Nigerian who was held, by millions of people, even in the second decade of the twenty-first century, to be literally infallible. She shivered.

She was taken to the top floor, and left alone in a corridor.

The view from here, of Rome bathed in the city Dome's golden, filtered dawn, was exhilarating. And the walls of the corridor were coated by paintings of dangling willow-like branches. Hidden in the leaves she saw bizarre images: disembodied heads being weighed in a balance, a ram being ridden by a monkey.

'• - . Officer Philmus. I hope you aren't too disconcerted by our decor.'

She turned at the gravelly voice. A heavy-set, intense man of around fifty was walking towards her. He was dressed in subdued, Plain black robes which swished a little as he moved. This was her contact: Monsignor Boyle, a high-up in the Vatican's Pontifical Academy of Science.

'Monsignor.'

Boyle eyed the bizarre artwork. 'The works here are five hundred years old. The artists, students of Raphael, were enthused by the rediscovery of part of Nero's palace.' He sounded British, his tones measured and even. 'You must forgive the Vatican its eccentricities.'

'Eccentric or not, the Holy See is a state which has signed up to the UN's conventions on the creation, exploitation and control of artificial sentience -'

'Which is why you are here.' Boyle smiled. 'Americans are always impatient. So. What do you know about Eva Himmelfarb?'

'She was a priest. A Jesuit. An expert in organic computing, who -'

'Eva Himmelfarb was a fine scholar, if undisciplined. She was pursuing her research - and, incidentally, working on a translation of Dante's Divine Comedy - and suddenly she produced a book, that book, which has been making such an impact in theoretical physics… And then, just as suddenly, she killed herself. Eva's text begins as a translation of the last canto of the Paradiso -'

'In which Dante sees God.'

'… Loosely speaking. And then the physical theory, expressed in such language and mathematics as Eva could evidently deploy, simply erupts.'

Himmelfarb's bizarre, complex text had superseded string theory by modelling fundamental particles and forces as membranes moving in twenty-four-dimensional space. Something like that, anyhow. It was, according to the experts who were trying to figure it out, the foundation for a true unified theory of physics. And it seemed to have come out of nowhere.

Boyle was saying, 'It is as if, tracking Dante's footsteps, Eva had been granted a vision.'

'And that's why you resurrected her.'

'Ah.' The Monsignor nodded coolly. 'You are an amateur psychoanalyst. You see in me the frustrated priest, trapped in the bureaucratic layers of the Vatican, striving to comprehend another's glimpse of God.'

'I'm just a San Francisco cop, Monsignor.'

'Well, I think you'll have to try harder than that, officer. Do you know how she killed himself?'

'Tell me.'

'She rigged up a- microwave chamber. She burned herself to

death. She used such high temperatures that the very molecules that had composed her body, her brain, were destroyed; above three hundred degrees or so, you see, even amino acids break down. It was as if she was determined to leave not the slightest remnant of her physical or spiritual presence.'

'But she didn't succeed. Thanks to you.'

The fat Monsignor's eyes glittered. He clapped his hands.

Pixels, cubes of light, swirled in the air. They gathered briefly in a nest of concentric spheres, and then coalesced into a woman: thin, tall, white, thirty-ish, oddly serene for someone with a sparrow's build. Her eyes seemed bright. Like Boyle, she was wearing drab cleric's robes.

The Virtual of Eva Himmelfarb registered surprise to be here, to exist at all. She looked down at her hands, her robes, and Boyle. Then she smiled at Philmus. Her surface was slightly too flawless.

Philmus found herself staring. This was one of the first generation of women to take holy orders. It was going to take some getting used to a world where Catholic priests could look like air stewardesses.

Time to go to work, Philmus. 'Do you know who you are?' 'I am Eva Himmelfarb. And, I suppose, I should have expected this.' She was German; her accent was light, attractive. 'Do you remember -' 'What I did? Yes.'

Philmus nodded. She said formally, 'We can carry out full tests later, Monsignor Boyle, but I can see immediately that this projection is aware of us, of me, and is conscious of changes in her internal condition. She is self-aware.'

'Which means I have broken the law,' said Monsignor Boyle dryly.

'That's to be assessed.' She said to Himmelfarb, 'You understand that under international convention you have certain rights. You have the right to continued existence for an indefinite period in information space, if you wish it. You have the right to readonly interfaces with the prime world ... It is illegal to create full sentience - self-awareness - for frivolous purposes. I'm here to assess the motives of the Vatican in that regard.'

'We have a valid question to pose,' murmured the Monsignor, with a hint of steel in his voice.

'Why did I destroy myself?' Himmelfarb laughed. 'You would think that the custodians of the true Church would rely on rather

less-literal means to divine a human soul, wouldn't you, officer, than to drag me back from Hell itself? - Oh, yes, Hell. I am a suicide. And so I am doomed to the seventh circle, where I will be reincarnated as a withered tree. Have you read your Dante, officer?'

Philmus had, in preparation for the case.

The Monsignor said softly, 'Why did you commit this sin, Eva?'

Himmelfarb flexed her Virtual fingers, and her flesh broke up briefly into fine, cubic pixels. 'May I show you?'

The Monsignor glanced at Philmus, who nodded.

The lights dimmed. Philmus felt sensors probe at her exposed flesh, glimpsed lasers scanning her face.

The five-hundred-year-old painted willow branches started to rustle, and from the foliage inhuman eyes glared at her.

Then the walls dissolved, and Philmus was standing on top of a mountain.

She staggered. She felt light on her feet, as if giddy. She always hated Virtual transitions. The Monsignor was moaning.

She was on the edge of some kind of forest. She turned, cautiously. She found herself looking down the terraced slope of a mountain. At the base was an ocean which lapped, empty, to the world's round edge. The sun was bright in her eyes.

A few metres down, a wall of fire burned.

The Monsignor walked with great shallow bounds. He moved with care and distaste; maybe donning a Virtual body was some kind of venial sin.

Himmelfarb smiled at Philmus. 'Do you know where you are? You could walk through that wall of fire, and not harm a hair of your head.' She reached up to a tree branch and plucked a leaf. It grew back instantly. 'Our natural laws are suspended here, officer; like a piece of art, everything gives expression to God's intention.'

Boyle said bluntly, 'You are in Eden, officer Philmus, at the summit of Mount Purgatory. The last earthly place Dante visited before ascending into Heaven.'

Eden?

The trees, looming, seemed to crowd around her. She couldn't identify any species. Though they had no enviroshields, none of the trees suffered any identifiable burning or blight.

She found herself cowering under the blank, unprotected sky.

Maybe this was someone's vision of Eden. But Philmus had been living under a Dome for ten years; this was no place she could ever be at peace.

'What happened to the gravity?'

Himmelfarb said, 'Gravity diminishes as you ascend Purgatory. We are far from Satan here ... I can't show you what I saw, officer Philmus. But perhaps, if we look through Dante's eyes, you will understand. The Divine Comedy is a kind of science fiction story. It's a journey through the universe, as Dante saw it. He was guided by Virgil -'

'Who?'

The Monsignor said, 'The greatest Latin poet. You must have heard of the Aeneid. The significance to Dante was that Virgil was a pagan: he died before Christ was born. No matter how wise and just Virgil was, he could never ascend to Heaven, as Dante could, because he never knew Christ.'

'Seems harsh.'

The Monsignor managed a grin. 'Dante wasn't making the rules.'

Himmelfarb said, 'Dante reaches Satan in Hell, at the centre of the Earth. Then, with Virgil, he climbs a tunnel to a mountain in the southern hemisphere -'

'This one.'

'Yes.' Himmelfarb shielded her eyes. 'The Paradiso, the last book, starts here. And it was when my translation reached this point that the thing I'd put in my head woke up.'

'What are you talking about?'

The priest grinned like a teenager. 'Let me show you my laboratory. Come on.' And she turned and plunged into the forest. Irritated, Philmus followed.

In the mouth of the wood it was dark. The ground, coated with leaves and mulch, gave uncomfortably under her feet.

The Monsignor walked with her. He said, 'Dante was a study assignment. Eva was a Jesuit, officer. Her science was unquestioned in its quality. But her faith was weak.'

Himmelfarb looked back. 'So there you have your answer, Monsignor,' she called. 'I am the priest who lost her faith, and destroyed herself.' She spread her hands. 'Why not release me now?'

Boyle ignored her.

The light was changing.

The mulch under Philmus's feet had turned, unnoticed, to a thick carpet. And the leaves on the trees had mutated to the pages of books, immense rows of them.

They broke through into a rambling library.

Himmelfarb laughed. 'Welcome to the Secret Archive of the Vatican, officer Philmus.'

They walked through the Archive.

Readers, mostly in lay clothes, were scattered sparsely around the rooms, with Virtual documents glittering in the air before them, page images turning without rustling.

Philmus felt like a tourist.

Himmelfarb spun in the air. 'A fascinating place,' she said to Philmus. 'Here you will find a demand for homage to Genghis Khan, and Galileo's recantation… After two thousand years I doubt that anybody knows all the secrets stored here.'

Philmus glanced at Boyle, but his face was impassive.

Himmelfarb went on, 'This is also the heart of the Vatican's science effort. It may seem paradoxical to you that there is not necessarily a conflict between the scientific world-view and the Christian. In Dante's Aristotelian universe, the Earth is the physical centre of all things, but God is the spiritual centre. Just as human nature has twin poles, of rationality and dreams. Dante's universe, the product of a thousand years of contemplation, was a model of how these poles could be united; in our time this seems impossible, but perhaps after another millennium of meditation on the meaning of our own new physics, we might come a little closer. What do you think?'

Philmus shrugged. 'I'm no Catholic'

'But,' said Himmelfarb, 'you are troubled by metaphysics. The state of my electronic soul, for instance. You have more in common with me than you imagine, officer.'

They reached a heavy steel door. Beyond it was a small, glass-walled vestibule; there were sinks, pegs and lockers. And beyond that lay a laboratory, stainless steel benches under the grey glow of fluorescent lights. The lab looked uncomfortably sharp-edged by contrast with the building which contained it.

With confidence, Himmelfarb turned and walked through the glass wall into the lab. Philmus followed. The wall was a soap-bubble membrane that stretched over her face, then parted softly, its edge stroking her skin.

Much of the equipment was anonymous lab stuff - rows of grey boxes - incomprehensible to Philmus. The air was warm, the only smell an antiseptic subtext.

They reached a glass wall that reached to the ceiling. Black glove sleeves, empty, protruded from the wall like questing fingers. Beyond the wall was an array of tiny vials, with little robotic manipulators wielding pipettes, heaters and stirrers running on tracks around them. If the array was as deep as it was broad, Philmus thought, there must be millions of the little tubes

Himmelfarb stood before the wall. 'My pride and joy,' she said dryly. 'Or it would be if pride wasn't a sin. The future of information processing, officer, perhaps of consciousness itself…'

'And all of it,' said the Monsignor, 'inordinately expensive. All those enzymes, you know.'

'It looks like a DNA computer,' Philmus said.

'Exactly right,' Himmelfarb said. 'The first experiments date back to the last century. Did you know that? The principle is simple. DNA strands, or fragments of strands, will spontaneously link in ways that can be used to model real-world problems. We might model your journey to Rome, officer, from -'

'San Francisco.'

The air filled with cartoons, twisting molecular spirals.

'I would prepare strands of DNA, twenty or more nucleotide bases long, each of which would represent a possible transit point on your journey - Los Angeles, New York, London, Paris - or one of the possible paths between them.'

The strands mingled, and linked into larger molecules, evidently modelling the routes Philmus could follow.

'The processing and storage capacity of such machines is huge. In a few grams of DNA I would have quadrillions of solution molecules -'

'And somewhere in there you'd find a molecule representing my best journey.'

'And there's the rub. I have to find the single molecule which contains the answer I seek. And that can take seconds, an eternity compared to the fastest silicon-based machines.' The cartoons evaporated. Himmelfarb pushed her Virtual hand through the wall and ran her fingers through the arrays of tubes, lovingly. 'At any rate, that is the challenge.'

Monsignor Boyle said, 'We - that is, the Pontifical Academy

- funded Eva's research into the native information processing potential of human DNA.' 'Native?'

Abruptly the lab, the wall of vials, crumbled and disappeared; a hail of pixels evaporated, exposing the Edenic forest once more.

Philmus winced in the sunlight. What now? She felt disoriented, weary from the effort of trying to track Himmelfarb's grasshopper mind.

Himmelfarb smiled and held out her hand to Philmus. 'Let me show you what I learned from my study of Dante.' The young priest's Virtual touch was too smooth, too cool, like plastic.

The Monsignor seemed to be moaning again. Or perhaps he was praying.

'Look at the sun,' said Himmelfarb.

Philmus lifted her face, and stared into the sun, which was suspended high above Eden's trees. She forced her eyes open.

It wasn't real light. It carried none of the heat and subtle weight of sunlight. But the glare filled her head.

She saw Himmelfarb; she looked as if she was haloed.

Then she looked down.

They were rising, as if in some glass-walled elevator.

They were already above the treetops. She felt no breeze; it was as if a cocoon of air moved with them. She felt light, insubstantial, like a child in the arms of her father. She felt oddly safe; she would come to no harm here.

'We're accelerating,' Himmelfarb said. 'If you want the Aristotelian physics of it, we're being attracted to the second pole of the universe.'

'The second pole?'

'God.'

Looking back Philmus could see the Earth, heavy and massive and unmoving, at the centre of everything, a ball of water folded over on itself. They were already so high she couldn't make out Purgatory.

Rising ever faster, they passed through a layer of glassy light, like an airliner climbing through cloud. As they climbed higher she saw how the layer of light folded over the planet, shimmering like an immense soap bubble. Embedded in the membrane she could see a rocky ball, like a lumpy cloud, below them and receding.

It was the Moon.

She said, 'If I remember my Ptolemy -'

'The Earth is surrounded by spheres. Nine of them, nine heavens. They are transparent, and they carry the sun, Moon, and planets, beneath the fixed stars.'

The Monsignor murmured, 'We are already beyond the sphere of decay and death.'

Himmelfarb laughed. 'And you ain't seen nothing yet.'

Still they accelerated.

Himmelfarb's eyes were glowing brilliantly bright. She said, 'You must understand Dante's geometrical vision. Think of a globe of Earth, Satan at the south pole, God at the north. Imagine moving north, away from Satan. The circles of Hell, and now the spheres of Heaven, are like the lines of latitude you cross as you head to

Philmus, breathless, tried not to close her eyes. 'You were telling me about your research.'

'… All right. DNA is a powerful information store. A picogram of your own DNA, officer, is sufficient to specify how to manufacture you - and everything you've inherited from all your ancestors, right back to the primordial sea. But there is still much about our DNA - whole stretches of its structure - whose purpose we can only guess. 1 wondered if -'

The Monsignor blew out his cheeks. 'All this is unverified.'

Himmelfarb said, ‘I wondered if human DNA itself might contain information processing mechanisms - which we might learn from or even exploit, to replace our clumsy pseudo-mechanical methods…'

Still they rose, through another soap-bubble celestial sphere, then another. All the planets, Mercury through Saturn, were below them now. The Earth, at the centre of translucent, deep blue clockwork, was far below.

They reached the sphere of the fixed stars. Philmus swept up through a curtain of light points, which then spangled over the diminishing Earth beneath her.

'One hell of a sight,' Philmus said.

'Literally,' said the Monsignor, gasping.

'You see,' Himmelfarb said to Philmus, 7 succeeded. I found computation - information processing - going on in the junk DNA. And more. I found evidence that assemblages of DNA within our cells have receptors, so they can observe the external world in

some form, that they store and process data, and even that they are self-referential.'

'Natural DNA computers?'

'More than that. These assemblages are aware of their own existence, officer. They think.'

Suspended in the air, disoriented, Philmus held up her free hand. 'Woah. Are you telling me our cells are sentient}'

'Not the cells,' the priest said patiently. 'Organelles, assemblages of macromolecules inside the cells. The organelles are -'

'Dreaming?'

The priest smiled. 'You do understand.'

Philmus shivered, and looked down at her hand. Could this be true? 'I feel as if I've woken up in a haunted house.'

'Except that, with your network of fizzing neurones, your clumsily constructed meta-consciousness, you are the ghost.'

'How come nobody before ever noticed such a fundamental aspect of our DNA?'

Himmelfarb shrugged. 'We weren't looking. And besides, the basic purpose of human DNA is construction. Its sequences of nucleotides are job orders and blueprints for making molecular machine tools. Proteins, built by DNA, built you, officer, who learned, fortuitously, to think, and question your origins.' She winked at Philmus. 'Here is a prediction. In environments where resources for building, for growing, are scarce - the deep sea vents, or even the volcanic seams of Mars where life might be clinging, trapped by five billion years of ice - we will find much stronger evidence of macromolecular sentience. Rocky dreams on Mars, officer!'

The Monsignor said dryly, 'If we ever get to Mars we can check that. And if you'd bothered to write up your progress in an orderly manner we might have a way to verify your conclusions.'

The dead priest smiled indulgently. 'I am not - was not - a very good reductionist, I am afraid. In my arrogance, officer, I took the step which has damned me.'

'Which was?'

Her face was open, youthful, too smooth. 'Studying minds in test tubes wasn't enough. I wanted to contact the latent consciousness embedded in my own DNA. I was curious. I wanted to share its oceanic dream. I injected myself with a solution consisting of a buffer solution and certain receptor mechanisms which -'

'And did it work?.'

She smiled. 'Does it matter? Perhaps now you have your answer, Monsignor. I am Faust; I am Frankenstein. I even have the right accent! I am the obsessed scientist, driven by her greed for godless knowledge, who allowed her own creation to destroy her. There is your story -'

Philmus said, 'I'll decide that… Eva, what did it feel like?' Himmelfarb hesitated, and her face clouded with pixels, Frustrating. Like trying to glimpse a wonderful landscape through a pinhole. The organelles operate at a deep, fundamental level… And perhaps they enjoy a continuous consciousness that reaches back to their formation in the primeval sea five billion years ago. Think of that. They are part of the universe as I can never be, behind the misty walls of my senses; they know the universe as I never could. All I could do - like Dante - is interpret their vision with my own limited language and mathematics.'

So here's where Dante fits in. 'You're saying Dante went through this experience?'

'It was the source of the Comedy. Yes.' 'But Dante was not injected with receptors. How could he -' 'But we all share the deeper mystery, the DNA molecule itself, Perhaps in some of us it awakens naturally, as I forced in my own body… And now, I will show you the central mystery of Dante's vision.'

Boyle said, ‘I think we're slowing.'

Himmelfarb said, 'We're approaching the ninth sphere.'

'The Primum Mobile,' said the Monsignor.

'Yes. The "first moving part", the root of time and space. Turned by angels, expressing their love for God… Look up,' Himmelfarb said to Philmus. 'What do you see?'

At first, only structureless light. But then, a texture…

Suddenly Philmus was looking, up beyond the Primum Mobile, into another glass onion, a nesting of transparent spheres that surrounded - not a dull lump of clay like Earth - but a brilliant point of light. The nearest spheres were huge, like curving wings, as large as the spheres of the outer planets.

Himmelfarb said, 'They are the spheres of the angels, which surround the universe's other pole, which is God. Like a mirror image of Hell. Counting out from here we have the angels, archangels, principalities, powers -'

'I don't get it,' Philmus said. 'What other pole? How can a sphere have two centres?'

'Think about the equator,' whispered Himmelfarb. 'The globe of Earth, remember? As you travel north, as you pass the equator, the concentric circles of latitude start to grow smaller, while still enclosing those to the south…'

'We aren't on the surface of a globe.'

'But we are on the surface of a 3 -sphere - the three-dimensional surface of a four-dimensional hypersphere. Do you see? The concentric spheres you see are exactly analogous to the lines of latitude on the two-dimensional surface of a globe. And just as, if you stand on the equator of Earth, you can look back to the south pole or forward to the north pole, so here, at the universe's equator, we can look towards the poles of Earth or God. The Primum Mobile, the equator of the universe, curves around the Earth, below us, and at the same time it curves around God, above us.'

Philmus looked back and forth, from God to Earth, and she saw, incredibly, that Himmelfarb was right. The Primum Mobile curved two ways at once.

The Monsignor's jaw seemed to be hanging open. 'And Dante saw this? A four-dimensional artefact? He described it?'

'As remarkable as it seems - yes,' said Himmelfarb. 'Read the poem again if you don't believe it: around the year 1320 Dante Alighiero wrote down a precise description of the experience of travelling through a 3-sphere. When I figured this out, I couldn't believe it myself. It was like finding a revolver in a layer of dinosaur fossils.'

Philmus said, 'But how is it possible… ?'

'It was not Dante,' Himmelfarb said. 'It was the sentient organelles within him who had the true vision, which Dante interpreted in terms of his medieval cosmology. We know he had wrestled with the paradox that he lived in a universe which was simultaneously centred on Earth, and on God… This offered him a geometric resolution. It is a fantastic hypothesis, but it does explain how four-dimensional geometry, unexplored by the mathematicians until the nineteenth century, found expression in a poem of the early Renaissance.' She grinned, mischievously. 'Or perhaps Dante was a time traveller. What do you think?'

The Monsignor growled, 'Are we done?'

'… You know we aren't,' Himmelfarb said gently.

Philmus felt overwhelmed; she longed to return to solid ground. 'After this, what else can there be?'

'The last canto,' the Monsignor whispered.

Himmelfarb said, 'Yes. The last canto, which defeated even Dante. But, seven centuries later, I was able to go further.'

Philmus stared into her glowing eyes. 'Tell us.'

And the three of them, like birds hovering beneath the domed roof of a cathedral, ascended into the Empyrean.

They passed into a layer of darkness, like a storm cloud.

The hemispheres of the 3-sphere - the Earth and its nested spheres, the globes of the angels - faded like stars at dawn. But Himmelfarb's eyes glowed brightly.

And then, space folded away.

Philmus could still see Boyle, Himmelfarb, the priest's shining eyes. But she couldn't tell how near or far the others were. And when she tried to look away from them, her eyes slid over an elusive darkness, deeper than the darkness inside her own skull.

There was no structure beyond the three of them, their relative positions. She felt as small as an electron, as huge as a galaxy. She

She clung to Himmelfarb's hand. 'Where are we? How far -'

'We are outside the Primum Mobile: beyond duration, beyond the structure of space. Dante understood this place. "There near and far neither add nor subtract ..." You know, we underestimate Dante. The physicists are the worst. They see us all running around as Virtuals in the memory of some giant computer of the future. Not to mention the science fiction writers. Garbage. Dante understood that a soul is not a Virtual, and in the Paradiso, he was trying to express the transhuman experience of true eternity -'

'What did he see?'

Himmelfarb smiled. 'Watch.'

… Philmus saw light, like the image of God at the centre of the angels' spheres. It was a point, and yet it filled space and time. And then it unfolded, like a flower blooming, with particles and lines (world lines? quantum functions?) billowing out and rushing past her face, in an insubstantial breeze. Some of the lines tangled, and consciousness sparked - trapped in time, briefly shouting its joy at its moment of awareness - before dissipating once more. But still the unfolding continued, in a fourth, fifth, sixth direction, in ways she could somehow, if briefly, conceive.

She felt a surge of joy. And there was something more, something just beyond her grasp -

It was gone. She was suspended in the structureless void again. Himmelfarb grasped her hand.

Boyle was curled over on himself, his eyes clamped closed. Philmus said, 'I saw -'

Himmelfarb said, 'It doesn't matter. We all see something different. And besides, it was only a Virtual shadow… What did you feel?'

Philmus hesitated. 'As I do when I solve a case. When the pieces come together.'

Himmelfarb nodded. 'Cognition. Scientists understand that. The ultimate cognition, knowing reality.'

'But now it's gone.' She felt desolate.

'I know.' Himmelfarb's grip tightened. 'I'm sorry.'

The Monsignor, his voice weak, murmured, '"I saw gathered… / Bound up by love in a single volume / All the leaves scattered through the universe; / Substance and accidents and their relations, / But yet fused together in such a manner / That what I am talking about is a simple light…"'

'Dante was very precise about how he interpreted what he saw,' said Himmelfarb. 'This is Aristotelian physics. "Substances" and "accidents" describe phenomena and their relationships. I believe-that Dante was trying to describe a glimpse of the unification of nature.'

'Yes,' Philmus whispered.

'And then he saw a paradox that he expresses by an image. Three circles, superimposed, of the same size - and yet of different colours.'

'Separated by a higher dimension,' Philmus guessed. 'Yes. In the high-dimensional artefact Dante saw a metaphor for the Trinity. God's three personalities in one being.'

'Ah,' said the Monsignor, cautiously uncurling. 'But you saw -' 'Rather more. I knew enough physics -'

'This is the basis of the new unified theory,' Philmus said. 'A unification of phenomena through the structure of a higher-dimensional space.'

Himmelfarb's face was turning to pixels again. 'It isn't as simple as that,' she said. 'The whole notion of dimensionality is an approximate one that only emerges in a semi-classical context - well. 1 don't suppose it matters now. I wrote it down as fast as I could, as far as I could remember it, as best I could express it. I don't think I could give any more.'

The Monsignor looked disappointed. Philmus said, 'And then -'

'I killed myself,' Himmelfarb said bluntly. Bathed in sourceless light, she seemed to withdraw from Philmus. 'You have to under-stand. It wasn't me. I had hoped to find enlightenment. But I was not enhanced. It was the organelles' vision which leaked into my soul, and which I glimpsed.'

'And that was what you could not bear,' the Monsignor said, Hanging like a toy in mid-air, he nodded complacently; evidently, Philmus thought, he had learned what had come to find, and Himmelfarb's essential untidiness - so distressing to Boyle's bureaucrat's heart - was gone. Now she was safely dead, her story closed.

Philmus thought that over, and decided she would prosecute.

But she also sensed that Boyle knew more than he was telling her. And besides… ‘I think you're wrong, Monsignor.'

Boyle raised his eyebrows. Himmelfarb hovered between them, saying nothing.

'Eva didn't quite finish showing us the last canto. Did you?' The priest closed her eyes. 'After the vision of the multidimen-sional circle, Dante says: "That circle… / When my eyes examined it rather more / Within itself, and in its own colour, / Seemed to be painted with our effigy…"' 'I don't understand,' the Monsignor admitted. Philmus said, 'Dante saw a human face projected on his multi-dimensional artefact. He interpreted whatever he saw as the Incarnation: the embodiment of God - beyond time and space -in our time-bound mortal form. The final paradox of your Christian theology.'

Boyle said, 'So the ultimate vision of the universe is ourselves.' 'No,' Himmelfarb snapped. 'Today we would say that we - all minds - are the universe, which calls itself into existence through our observation of it.'

'Ah.' Boyle nodded. 'Mind is the "eternal light, existing in ourselves alone, / Alone knowing ourselves ..." I paraphrase. And this is what you saw, Eva?'

'No,' said Philmus. She felt impatient; this insensitive asshole was supposed to be a priest, after all. 'Don't you see? This is what Himmelfarb believed her passengers, the sentient organelles, would see next; she had the guidance from Dante's sketchy report for that. And that's what she wanted to prevent.'

'Yes.' Himmelfarb smiled distantly. 'You are perceptive, officer. Are you sure you aren't a Catholic?' 'Not even lapsed.'

Himmelfarb said, 'You see, Dante's quest did not end with discovering an answer, but with the end of questioning. He submitted himself to the order of the universe, so that his "desire and will / Were… turned like a wheel, all at one speed, / By the love which moves the sun and the other stars".'

Philmus said, 'And that was the peace the organelles achieved, the peace you glimpsed. But you knew, or feared, you couldn't follow.'

'And so,' said Boyle, 'you destroyed yourself -' 'To destroy them. Yes.' Her expression was bitter. 'Do you understand now, Monsignor? Of course this is the end of your religion - of all religion. We are accidental structures, evanescent, tied to time and doomed to oblivion. All our religious impulse, all our questing, all our visions - just a pale shadow of the organelles' direct experience. They have God, Monsignor. All we have are Dante dreams.'

Philmus said, 'You were happy to be Dante. But -' 'But I refused to see them go where I couldn't follow. Yes, I could be Dante. But I couldn't bear to be Virgil.'

'I absolve you of your sin,' the Monsignor said abruptly, and he blessed Himmelfarb with a cross, shaped by his right hand.

Himmelfarb looked shocked - and then an expression of peace crossed her face, before light burst from within her, dazzling Philmus.

When her eyes recovered Philmus was embedded in space and time once more: alone with the Monsignor, in the sixteenth century corridor, where the willow branches were merely painted.

Philmus met the Monsignor one more time, at the conclusion of the hearing in the New York UN building. The UN Commission had found against the Vatican, which would have to pay a significant fine.

Boyle greeted Philmus civilly. 'So our business is done.'

'Do you feel we reached the truth, Monsignor?'

He hesitated. 'I don't know what to believe. The analysis of Eva's monograph is continuing. The NASA people have taken up her suggestion of alternate evolutionary directions for macromol-ecules on Mars, and the exobiologists are modelling and proposing

missions. We haven't been able to recreate Eva's lab results: to retrace her "footprints in Hell", as Dante would say. Perhaps it was all a fever dream of Eva's, brought on by overwork and too much study. It wouldn't be the first such incident in the Church's long history.

'Or perhaps we are indeed hosts to another sentience. Perhaps one day it will awaken fully. If it does, I hope it will treat us with compassion. And what do you believe, officer Philmus?'

I believe that whatever the Vatican finds, whatever it knows, it will keep to itself, in the Secret Archive.

'I'm reading Dante.' It was true.

The Monsignor smiled. 'But you hate poetry.'

'It's the only place I can think of where I might find the answers. Anyhow, it's something to do in the small hours of the night. Better than -'

He said softly, 'Yes?'

'Better than to lie there listening to my body. Wondering who else is home.'

He whispered, 'Dante dreams? You too?'

'Monsignor - you realize that if Eva was right, she achieved first contact.'

His face was calculating, but not without sympathy. 'The Vatican is very old, officer. Old, and secretive. And - though without the tools of modern science - we have been investigating these issues for a very long time.'

She felt her pulse hammer. 'What does that mean?'

'There are many ways to God. Perhaps Eva indeed made contact. But - the first?'

He smiled, turned and walked away.

War Birds

November 1969:

The dust of the Moon crunched under Burdick's feet. His footprints, in the low sunlight, under the black sky, were clear and sharp, embedded in billion-year-old regolith.

When Burdick bent and ran his hand through the dirt, it looked a lot darker: almost black, like charcoal. The dirt gave easily for the first couple of inches, but then resisted his gloved fingers.

They'd brought shovels. But it wasn't going to be so easy to dig out graves, here on the Moon.

Here came Harry Singer, his commander, bouncing across the flat, pitted surface of the Sea of Tranquillity. Harry was humming his dumb little country tunes. He had been on a high since that moment when he had brought Guardian, still fat on fuel, drifting over this enigmatic ground, and they'd spotted Eagle itself, glittering like a toy against the greyness. Burdick understood how he felt. The tough part of the mission was still to come. Let Harry savour the triumph of the landing.

Burdick felt on a high himself. At thirty-nine, after eight years in the space programme, he was no longer a rookie. Of course after Apollo 12 was redirected, he wasn't where he'd expected to be, in the Ocean of Storms. And he wasn't going to be doing all the geology and stuff he'd been trained to do. But he'd never made much sense of all the science shit anyhow.

And here he was, after all, on the surface of the Moon itself.

Harry was looking at him. He straightened up.

It was time to do his duty.

Side by side, two USAF officers on the surface of the Moon, they faced Eagle.

Neil Armstrong's LM was a spidery construct of aluminium sheets and struts, sitting there like a little house. It didn't show many signs of its four-month stay. Maybe the gold insulation blanket on that descent stage was a little pitted. Maybe the colours of the Stars and Stripes painted there had faded a little.

But the four spider legs had collapsed. When it exploded, the boxy heart of the descent stage had just crumpled up and fallen against the dust. The bulbous ascent stage looked intact, but it was tipped over through thirty or forty degrees, and Burdick could see a split down one seam. Eagle sagged like a deflated balloon.

The surface here was littered by bits of twisted-up aluminium hull, and by shards of blown-out insulation blanket, a raying that overlaid the subtler disturbance of the LM's descent engine fire. But there were no footprints here. Nobody had climbed down from this LM. Armstrong and Aldrin had been the first humans to reach another world, and had lived less than a minute to enjoy

'Let's get it over,' Singer said.

Something was glittering, at the edge of Burdick's vision. Something metallic. At first he thought it was some other piece of the Eagle, broken off and hurled over the regolith.

But that couldn't be right. It was just too big.

It was the size and shape of a steel bathtub, mounted on six, no, eight spidery wheels. There was an open lid encrusted with what looked like solar cells. A couple of antennae, cones and rods, stuck out of the interior.

Something moved: two big camera lenses, fixed to the front of the car, swivelling up to inspect him.

T don't believe it,' Singer said. 'It's a fucking Lunokhod.'

'The Soviets.'

'Yeah. Come to see what they did. Come on,' said Harry Singer. And he picked up a Moon rock.

Burdick bent, stiff in his pneumatic suit, and got hold of the biggest boulder he could find. It would have been too heavy for him on Earth, probably, and here he could feel its mass, liquidly resistant to motion. Like a miniature Moon itself, the rock was pitted with craters, from a fingertip's width all the way down to fine little pinholes. It was probably billions-of-years old.

Burdick and Singer stalked across the shining surface, and lifted up their Moon rocks, and began to beat the Lunokhod, smashing

away the antennae and the fragile camera assemblies and the sheet of solar cells, their ancient rock weapons splintering in their hands, a quarter of a million miles from home. The sun was bright and in Burdick's eyes, and, under his Snoopy hat, he could feel sweat starting over his brow.

August 1981:

Control, this is Aldrin. Commander's voice check, over. Roger, over. Control, this is the pilot. Voice check, over. Roger, over…

The sun was bright and in his eyes, and, under his peaked Air Force officer's cap, Burdick could feel sweat starting over his brow.

It was early morning. He was looking east, right into the sun. Beyond the tree line, there was Launch Complex 39, the twin pads loaded up with their Shuttles: 39-B to the left, with Aldrin, 39-A to the right, with Enterprise. Enterprise was due for launch tomorrow, and was still enclosed in its rotating structure, but Aldrin was exposed, ready to fire.

He could smell the sea. There were still bands of mist lingering over the flat salt marshes, and he could hear the cry of the gulls wheeling around the gantries.

Burdick was glad to get out of the Kennedy Space Center executive offices and come up here on the roof to see the launch. As Chief Astronaut it was his duty to show up here rather than in the Firing Room, which would be his inclination. But the astronauts' families were here, and downstairs it was like a kindergarten. The youngest kids had soon got bored waiting for the launch and were crawling around over the floor, playing with orbiter models and mission patches.

He was kind of pleased that his own son, Phil Junior, ten years old, eschewed such games. Today, for instance, he was off with the Eagle Scouts. It would have been nice to have him up here, Burdick thought, but it was more important to give the little soldier his independence.

This roof was full of VIPs and NASA brass. Here was the new President, Reagan himself, with his first lady, grinning and glad-handing, with Richard Nixon, rehabilitated as Reagan's secretary of state. And there was Curtis LeMay, the old Cold Warrior, brought out of retirement to serve as Air Force chief of staff, following his commander and chomping away on one of his trademark cigars, squat and bustling and competent.

All the civilians were wearing big wide-brimmed hats and

sun-block, even Reagan. If you worked here you were supposed 'to wear filters over your mouth and nose. Some of the pad rats, it was said, had come down with lesions seared into their lungs. But to Burdick that was all bullshit. The ozone layer may or may not have been depleted by all these space launches. And he knew some of the techs were concerned about launching at the height of summer, when all that u-v etched away at the perishables on the orbiter stack. But then those guys beefed about launching in winter too, when ice clustered on the stack and the perishable components, rubber and plastic, got too stiff.

So there was more u-v. So they all had to paint their houses more often these days. So what? What the hell were they supposed to do? Stop launching?

The dominant object in his skyline was the VAB, the Vehicle Assembly Building, a monstrous black-and-white cube, built to assemble Moon ships. The cliff-face wall of the VAB was still scarred by the splash of the petrol bombing, where Star Trek fans had broken in to protest at the name of their beloved fantasy spaceship being given to a Shuttle orbiter, a war bird.

There was a big parking lot at the base of the VAB, pretty much deserted today except for the buses which had brought in the press guys. He remembered how different it was in the sixties, when the lot was always jammed with rows of vehicles, gleaming in the Florida sun like so many metal beetles. But the road traffic had never recovered from the oil price hike that had followed Reagan's I nuking of Iran, despite the peacemaking efforts of the restored Shah with those Arabs.

As the mist burned off, over on the horizon, he could see the gleaming white of the orbiter, Aldrin, against its orange External Tank. He needed his binoculars to see the four solid rocket boosters clustered around the orbiter. This was a stretched Shuttle configuration, designed for heavy lift, a hundred and thirty-five tons to low Earth orbit, more than twice the baseline design's capacity. And he knew Enterprise, right now, was being fitted with the new liquid fuel boosters, another upgrade path.

Today's launch would be the fourth flight of the four-booster configuration, and the first orbital test of the NERVA 3 nuclear tug. That NERVA was going to be sent around the Moon, unmanned, and then, the plan went, later in the year there would be a couple of manned test flights, and maybe a Moon mission as early as next year. It was all part of the plan to establish a

nuclear silo up there on the Moon: more silent sentinels, warning off any possible aggressors.

The NERVA was the reason there were so many VIPs here, on this roof and in the VIP stand.

This would be the twenty-first Shuttle launch of the year, from the Cape and Vandenburg, and the ninety-first of the programme in all, since the first successful orbital flight, bang on schedule in 1977. This year alone there ought to be forty-four launches, maybe fifteen of them USAF missions, using the Air Force's own two dedicated orbiters launched out of Vandenburg.

The Shuttle had turned into a magnificent success. Everyone had been determined to make it so, NASA, USAF and contractors alike. And Burdick, since he'd transferred from the Moon programme after it was closed down with Apollo 12, had been proud to play his part in that.

There was nothing about the Shuttle programme today that hadn't been in the plans right back in 1969, even before Apollo 11 landed. But Eagle, Burdick guessed, had given everyone a little incentive to get it right. Stunt flights to the Moon could wait. Space was the high ground, and if America didn't make it secure, the Soviets would, and there would be hell to pay.

And the Shuttle, with all its military applications - reconnaissance, interception, satellite recovery, hunter-killer capabilities, rescue and relief - was the key.

So here they were, operating five orbiters just as advertized, with an eleven-day airline-style turnaround between each flight, and with the components of Space Station Freedom, an outpost on that high frontier, already being assembled in plants in California and Texas and Alabama.

Anyhow, once old Walter Dornberger, von Braun's old boss, had been brought out of retirement and started applying a little of that old Peenemunde discipline to the project, everything got a lot tighter.

The countdown went through smoothly, as it always did.

Up on the roof, Burdick did his share of the gladhanding and flesh-pressing. But he ducked out once the count neared its conclusion. He was here for the launch, after all.

At main-engine start, a bright white light erupted at the base of the orbiter, and white smoke squirted out to either side.

There they go, guys, three at a hundred.

Then the four solid boosters lit up, showering orange smoke,

yellow sparks. The stack lifted off the ground, startlingly quickly, trailing a column of white smoke which glowed orange within, as if on fire. The plume of yellow light from the SRBs was incredibly bright - dazzling, like liquid light, like sunlight seen from the Moon.

There was clapping and hollering from the dignitaries and crew relatives. Burdick kept his binoculars clamped to his face.

The stack arched over onto its back and followed a steep curve away from its tower. Already the gantry was dwarfed by the smoke column. After ten seconds the Shuttle punched through an isolated thin cloud, threading it like rope.

The sound reached him after fifteen seconds: a crackling thunder which came tumbling down over him, sharp slaps over an underlying rumble.

It was a hell of a thing, he thought.

And then -

It looked as if the SRBs had detached a little early. The single vapour trail split up into five, the orbiter itself with its main engines burning white, and the four SRBs careening out of the smoke, like diverging fingers.

Shit, he thought.

The orbiter blew first, that big External Tank on its belly just cracking open, oxygen and hydrogen igniting in a single pure blast. And then the four SRBs went up like firecrackers around that central glare, destroyed by the Range Safety Officer.

We have no downlink at this time. We're obviously studying the event.

He could still hear the routine rocket noise flowing over him, like a ghost, the sound of the disaster itself still suspended in the ruptured air.

The NERVA, he thought. How many pounds of fissile uranium had just been smeared over the Florida sky?

Reagan. They had to jet the President under cover.

He looked around, through a crowd that had turned into a mob of screaming, crying people. There: Curtis LeMay had his arm around Reagan's shoulders, and was hustling him away, towards the door from the roof. Burdick could hear what LeMay was saying to the ashen President. We can't tolerate this, sir. We have to consider eradication. I'm talking about Project Control, Mr President. We've been talking about this since the 1950s at the Air War College. We aren't talking about pre-emptive strikes, sir,

but about the historic rollback of the Soviet Union. It's time… Old Nixon was nodding gravely.

Burdick stayed on the roof, a handkerchief on his mouth against the fall-out, until all the women and children had been escorted out of the open air.

January 1986:

As the pilots prepared for the interception, Yeager's flight deck was like a little workshop, Burdick thought, glowing with the lights of Earth, and the crews' fluorescent glareshields. The battleship-grey walls were encrusted with switches and instruments that shone white and yellow with internal light, though the surfaces in which they were embedded were battered and scuffed with age and use. There was a constant, high-pitched whir, of environment control pumps and fans.

Once more he had control pedals at his feet, a joystick between his legs. He felt at home. The Shuttle orbiter was a fine old warplane.

The Soyuz target had been over Iraq when Yeager launched from Vandenburg, and there had been a gap of ten thousand miles between them. But orbital mechanics brought him ever closer to his prey, at a rate of a thousand miles per orbit.

Anyhow there was no rush. The Shuttle was fitted with its extended-duration pack, solar panels that had unfolded from the payload bay like wings. They could stay up here for a month if they needed to.

Burdick even had time to send a message down a secure line to Fay at Vandenburg, and to Philip Jr, who was, at fifteen, a cadet at St John's Military Academy in Wisconsin.

It was good to be back in command.

Since he'd been moved upstairs he was enjoying his assignment as head of the Office of Manned Spaceflight. But flying a desk was no substitute for flying Shuttle. At fifty-six, he'd thought he was too old to fly again, but Hans Mark - NASA Administrator, former Air Force secretary and physicist under Edward Teller -had persuaded him to come out of retirement for this one mission. Space Command needed all the pilots it could get right now, and even if this mission wasn't the most glamorous of Project Control - those had to be the dramatic high-atmosphere swoops of Adams and Falcon and Enterprise, as they had dropped their bomb loads over the USSR, far out of reach of any intercept capability -

cherry-picking the last Soyuz spy ship had to be the most technically challenging, and fun.

The ground track took them over the Soviet Union a couple of times. Even now, a month after Project Control had reached its spectacular climax, he could still see the glowing craters where the space centres at Volgograd and Kapustin Yar used to be. The whole country was pretty dark, although he could see cities burning around the rim of Russia itself: in the Moslem republics of south Asia, and the Baltic republics, and even the east European satellites.

Of course there was a price to pay. Before it collapsed, the Soviet government had shot off a few of its own nukes. Warsaw was gone, for instance. And there were rumours of trouble on the long Chinese frontier. But that was okay by Burdick. Everybody had taken the chance to kick the old bear when he was down, and Burdick guessed they were entitled.

Not that everyone agreed. Before the UN had been thrown out of New York there had been pretty near universal condemnation of the US's actions, universal except for the British anyhow. But the UN were assholes. It was no more than you'd expect from a bullshit factory like that.

When he passed over the US, it was strange to see Florida from orbit, that big black scar down its evacuated eastern coast. Not that the loss of the Cape was so grievous. The Aldrin disaster, in the end, had just expedited LeMay's plans to transfer all the Shuttle resources to the USAF. The climate at Vandenburg was a lot more stable for landings anyhow.

Funny thing that the Aldrin crash, which had spurred off Project Control in the first place, had turned out to be caused by a simple glitch, a fuel line that had perished from u-v exposure. Not sabotage at all. Burdick didn't suppose it mattered. Control would have come about anyhow. There had been a whole string of provocations from the USSR: Afghanistan, their own unmanned Shuttle, the damn Salyut spy platforms. These things had a huge historic inevitability to them, it seemed to him.

His crew, all USAF officers, was working well, just like the drill. Even young Tom Gibson, up here on his third mission, who had spent half his time throwing up, was working well with the handheld laser-ranging device, checking Burdick's position.

Burdick suspected he intimidated these junior guys. They all seemed so damn young. And how must he seem to them? - the

only Moonwalker left flying, like some monolith from the past.

The youngsters were all wearing the smart new black uniforms of Space Command, with their thunderbolt flashes and bright logos. The uniforms looked good, and had struck a chord in the public mind, Burdick knew. Air Force Space Command seemed to represent a certain order, in a country beset by foes abroad, and trouble at home: revolutionaries everywhere, and polyglot cities, and hippies and anarchists and sex maniacs and drug addicts and activists and homosexuals and punk rockers and soaring crime…

The Rocket State, they called it: the goal was a conflict-free society administered from above, dominated by technology and smart young men like these, embodying the eternal American values of piety, hard work, family and flag. Just like the USAF, and NASA.

Order, imposed from space.

And now that Project Control had been implemented, that order would spread across the planet: Pax Americana, in the face of which all the old illogical ethnic and religious differences would dissolve, and mankind would come to its senses, and progress to a better tomorrow.

And so on. Burdick accepted it all. It was a fine vision. He'd welcomed the executions of Jane Fonda and Jesse Jackson and John Lennon and the rest of those fellow travellers for their treasonous subversion, the hell with them.

But even so these new uniforms made him feel just a little uncomfortable. They were too close to the images from Germany he'd grown up with as a kid. It was a kind of easy glamour, he thought. He preferred good-old Air Force blue.

A couple more burns to tweak his orbit, and then they were closing fast on Soyuz. Burdick went through his terminal initiation burn, and then his rendezvous radar started to track the bogey. He assumed the low-Z position beneath the little Russian ship and used his reaction thrusters to push up towards Soyuz from beneath.

Now he could see Soyuz, through the little rendezvous windows above his head.

The body of Soyuz was a light blue-green, an unexpectedly beautiful, Earthlike colour. Soyuz looked something like a pepperpot, a bug-like shape nine feet across, with its fat Orbital Module stuck on the nose of the main body, a truncated cylinder, capped by the headlight-shaped Descent Module. Two matte-black solar panels

jutted from its rounded flanks, like unfolded wings, and a parabolic antenna was held away from the ship, on a light gantry.

Soyuz was basically an Apollo-era craft, still flying twenty years later. It looked, frankly, like a piece of shit to Burdick.

Soyuz was floating right down into Yeager's gaping-open payload bay, like a minnow drifting into the mouth of a shark.

Tom Gibson was working the RMS now, the remote manipulator arm. The RMS had a heavy industrial-strength cutting laser bolted to its end, and Tom just reached up and snipped off the solar-cell wings of Soyuz, snip snip, like cutting the wings off a fly. Those solar panels drifted away, sparkling as they twisted. It was expertly done, and Burdick didn't even need to slow down his rate of approach.

The laser had come out of JPL, which had started producing some fine military applications since its weaponization in 1980.

The crippled Soyuz settled neatly into the payload bay, as if the Shuttle orbiter had been designed for the job. Which, of course, it had.

Burdick got into his EVA suit and, with two of his crew, made his way out through the airlock in back of the flight deck. The big bay doors were gaping open, the silvered Teflon surfaces of their radiator panels gleaming in Earthlight. The bay itself was a complex trench, crammed with equipment, stretching sixty feet ahead of him.

Soyuz sat where it had settled, an ugly insect shape, cluttering up the bay.

The others worked their way around Soyuz, strapping it into position for the glide home. Burdick made his way to the nose of Soyuz, to the complex docking hatch there.

The hatch was already open, the docking probe disassembled. He was, it seemed, expected.

Burdick, alone, pushed his way into the Orbital Module. There were bright floodlights here. He shut the hatch behind him, as he'd been trained, and worked a control panel. He heard a hiss, as air gushed into the module.

The Orbital Module was a ball just big enough for one person to stretch out. It would have been discarded to burn up during the re-entry, so it was packed full of garbage: food containers and clothing and equipment wrappers, like a surreal blizzard. This crew had been going home, when their country went up in flames.

When the pressure was restored, Burdick cracked his bubble

helmet and took it off. There was a stale smell, and his ears popped as pressure equalized.

The hatch to the Descent Module opened. Burdick drifted through.

The Descent Module cabin was laid out superficially like an old Apollo Command Module, with three lumpy-looking moulded couches set out in a fan formation. Big electronics racks filled up the space beneath the couches.

There was a single cosmonaut here, in an open pressure suit, staring up at him from the centre couch. He was squat, dark, his face as wide as the Moon. He looked to be about Burdick's age.

'Dabro pazhalavat,' he said. 'Welcome. I am Colonel Sergei Kozlov.' He held up a little tray, with food. 'Bread and salt. A traditional Russian greeting.'

'The hell with it.'

'Take the damn bread, General Philip Burdick.' Burdick hesitated. Then he floated down, and took the bread. He chewed a little of it. It was heavy, sticky. 'You know my name?'

'Konyeshna. Of course. You were a Moonwalker. I saw you approach, on the surface of the Tranquillity Sea.' 'Huh?'

'I was teleoperating Lunokhod. I saw you wield your rock. It massed, I hazard, more than you collected as geological samples to bring home.'

'We weren't there for fucking geological samples.'

'Indeed not. And you are not here for scientific purposes now, are you?'

'Nor you, sir. We know this Soyuz is stuffed full of results from your surveillance activities on the Salyut.'

'That is true. But what does it matter? General Burdick, I am the last serving Soviet officer. I have no one to report to.'

Burdick discarded his bread. 'Colonel, you'll come onto the flight deck, and we'll take you home.'

'Home?'

'The United States.'

'Will there be TV cameras? Will you parade me?'

'We'll land at Vandenburg. The air base in California.'

'Konyeshna. Where I aim to apply for political asylum.' He grinned. 'Does that surprise you, General? But what have I to return to? The radioactive winds which blow across the steppe? Your slow dismantling of my nation?'

'Rebuilding. We'll rebuild your country. We aren't barbarians.'

'Thank you,' Kozlov said dryly. 'But it was unnecessary. Don't you see that, General? We were no threat to you. Not really. Nor was Lunokhod. On the Moon, we were only curious, as you were. We were going to change anyway. We had to. We couldn't afford to keep up with you. You could have waited. A little patience.' Kozlov smiled. 'But I forgive you. Come. I am impatient to see your wonderful Space Shuttle.'

Kozlov began to remove his couch restraints.

September 1993:

Burdick was impatient to see Phil's Space Shuttle.

Here he was actually cutting his lawn, a real old geezer thing to do, here in the middle of Iowa. Just what he'd always imagined retirement to be, back home in small-town America, where he'd started from. Well, hell, he was sixty-three now, and thanks to the mess space radiation had made of his central nervous system - so the surgeons told him - he looked and felt a lot older. He was entitled to his gentle retirement.

Fay came out with a glass of chilled lemonade, and to remind him that the flight was due overhead.

He cut the mower's engine. Grass clippings sank to the ground, slower than Moondust. He took off his hat and wiped the sunblock off his nose.

He limped to the porch chair. His right leg was paining him again, the one he'd broken a couple of times already. Premature osteoporosis, they said, all that bone calcium leached away in his piss in space, but what the hell.

He sat down, to wait to see Phil.

While he'd been cutting, ruminating, the sun had gone down on him. The first star was out: Venus, undoubtedly, down there on the horizon. There was one hell of an aurora tonight, reaching down from the north. Never used to get auroras in southern Iowa when he was a kid. Something to do with the bombs, the weather girl said.

There was some reading matter on the seat. Here was the speech by Curtis LeMay, venerable Chief of the Air Force, that he'd given to the USAF Association National Convention, out at Albuquerque. It was about his Sunday Punch scheme.

… and even as we have crushed the heart of Asia, we have to look further ahead.

President Reagan's decision to punish China's assault on Space Station Freedom was brave and correct. Let the ruins of the Forbidden City stand forever as a monument to our determination to maintain our grip on the high frontier, space! And yet the Chinese leadership continues to defy us, in every international forum.

And meanwhile, the incursion in Turkey of the Arab League under Saddam Hussein is equally unacceptable. Our pre-emptive nuclear assault on Iraq was surgical, necessary and justified. Contrast that with Saddam's recent assault, with Chinese CSS-2 missiles, on our Space Command base at RAF Fylingdales, England, exploiting a dirty and unreliable warhead.

We must not allow the warlords of darkened Asia to believe that we can be defied with impunity. Remember, these people are not like us! They are calculating, amoral machines. We must demonstrate our strength of arm and will to them. We have the whole of the future, the whole of infinite space, before us to conquer. But we must act now. We must show we are ready!…

The word was LeMay had Reagan's ear.

Not that anyone knew how much that meant. Even as the Constitution was being bucked again to allow Reagan to run for a fifth term, the rumours were that Reagan's Alzheimer's was becoming pronounced, and his veep, Nixon, was the real power behind the throne. Burdick didn't suppose it mattered.

The stars were coming out now, pushing through the remnants of the blue blanket of day. It was a good clear night: no rain, a light dew and the weather girl said there'd be no fall-out threat.

… I am saying that we have to be prepared! If America is going to survive in this tough old world she has to show that she's prepared to meet any threat, to fight to the last with utter inhibition, whenever she's asked to.

Ladies and gentlemen, we won the Cold War with Project Control. Now I'm asking you to endorse our next great task, the demonstration of our will to all of Africa and Asia and Europe: the Sunday Punch…

LeMay was offering Burdick the chance to return to the Moon. Now, that would be a hell of a thing. Burdick wasn't too old to fly. Such was the demand for experienced astronauts, with more than sixty Shuttle flights a year, there were plenty of creaky veterans older than Burdick still scooting about up there, including his old

buddy Harry Singer, for instance, now so racked by calcium depletion - so they said, anyhow - that he couldn't come back down again.

It would be interesting to see the Earth from space again. They sent up Walter Cronkite himself a year ago, when they inaugurated the new Shuttle fleet: fully reusable now, with the DC-io-sized orbiter riding to space on the back of a 747-sized winged booster, just like the first designs back in '69 before the Congressional budget-choppers got ahold of the programme. It had been a hell of a thing to hear that familiar dark brown voice booming down from orbit.

But Cronkite's descriptions of the Earth - the scarred steppes of Asia, the smoking rubble of eastern Europe, even the spreading darkness at the heart of America's own cities - didn't coincide much with his own recollections. Cronkite even claimed to have seen, from orbit, the destruction of Sioux City, Burdick's own home town, by rebelling students and anarchists. It was a little hard to verify such things. The news was pretty heavily censored these days, for valid reasons of national security.

Still, Pax Americana somehow hadn't worked out quite the way everyone thought.

Anyhow it was too late for Burdick. His time had come and gone. He was content to watch, now.

And besides -

Sunday Punch. That cosmonaut defector he'd brought down from orbit, Sergei Kozlov, sent him long letters about the dangers of the project.

… You aren't like these others, my friend, these young ones in their un-American uniforms. You must see that some of them actually want it all to end - to pull down the house - to destroy all the little people, dirty and squabbling and unpredictable, who don't understand their giant schemes…

Hell, Burdick wasn't qualified to judge what Kozlov said. Kozlov was just some Russian who'd grabbed the opportunity to stay in the US, when it came to him, with both hands. He'd even managed to get his family out before the Chinese invasion and all hell finally broke loose over there.

But Burdick had to admit to a few doubts himself, deep in his gut. There were always unexpected consequences, of whatever you did.

Anyhow here came the Lockheed PowerStar: a brilliant flare of

light, like a high-flying plane, climbing steadily over the dome of the sky.

It was time. He called Fay. She came out with more lemonade, and settled down beside him.

The power station was a rectangle of black solar cells, twenty miles long and four wide, with a cluster of Shuttle External Tank hab modules bolted to its spine, as productive as ten nuke plants, so relieving the lack of Mid-East gas that had half-crippled the economy for two decades now.

Pretty soon, it was said, the US wouldn't need the rest of the planet at all.

If Burdick had one regret about his retirement it was that he hadn't got up to orbit to see them putting the plant together, working the beam builders as they extruded their three-hundred yard lengths of foamed steel. It had made for great TV.

And there was a little firefly spark, climbing up the sky, right alongside the power plant: the orbiter Eagle II, commanded by Tom Gibson, carrying Burdick's only son Philip on his first spaceflight. A hell of a thing: two generations of Burdicks, climbing into space.

The rookies seemed to be getting younger every year, to Burdick. Phil Jr was only 22. Well, it was an expansive programme. It ate up crew members.

Unexpected consequences.

Sunday Punch was such a damn huge blow, who could say what the consequences would be? Certainly not Burdick.

Not that he admitted as much to Sergei Kozlov, or Fay, or anyone else. He'd learned to keep a lot of his thoughts to himself. It was a lesson he'd learned on the surface of the Moon, in the rubble of Apollo 11. There were some things better left unsaid. Truth was just another weapon anyhow.

He watched as the PowerStar slid down the sky, taking Phil's slowly converging orbiter with it, until it was lost in the deep blue haze on the horizon.

He sipped his lemonade. He could feel dew on his cheeks already. It made his skin-cancer scars itch.

He could always stay out another ninety minutes until Phil came round the Earth again. But it was kind of cold.

Fay had fallen asleep anyhow, her careworn face slack, the shadows on her lined face like pools of black oil.

September 1997:

The Florida beach was empty. The sand was hard and flat. A little way inland, there was a row of scrub pines, maybe ten feet tall. The moonlight shadows at their roots were like pools of black oil.

Burdick limped south.

The Moon, to the east, was fat and full, its silver light glimmering off the hide of the Atlantic. To Burdick, here in the grass, the Moon looked like it always had, when it had floated over the Iowa farm of his boyhood, when he'd gone barnstorming over those ash-grey plains with Harry Singer.

But not much longer, he supposed. Not if that old Sunday Punch worked like it was supposed to.

The wind was coming off the ocean. It wasn't cold, but he shivered anyhow, as he thought of the fallout shit it was probably blowing over him, across the sea from Asia. But he was wearing his facemask, and the easterly wind ought to keep the Canaveral crap away from him anyhow.

A flatbed truck had been crudely parked in the dune grass. Burdick could see its tracks, snaking back over the sand. And here were scuff marks where some kind of equipment had been hauled off the back and over the sand, down towards the water.

It looked like Kozlov had been telling the truth about coming down here, whatever he was planning.

Burdick wondered what the hell be was doing here, standing in a radioactive sea breeze, on the night of Sunday Punch. But then, he had no place else much to go, not since the Chinese shot down Columbia II, with Phil aboard, and Fay had followed him to the grave soon after. The house in Iowa, his lawn, lost its appeal after that, and he started drifting. But there were travel restrictions in place across the country, and after the Guatemalans took out San Antonio, with a nuke on an old Soviet SS-25, you weren't allowed in or out of Texas at all.

Difficult times. Oddly, through his enigmatic, disjointed letters, Kozlov, the old enemy, had come to seem a friend.

Anyhow, here he was.

Singing came drifting up from the water's edge: thick and heavy, like black Russian bread. The voice of an old man. Something going on down there. Somebody moving around, silhouetted by moonlight, a heavy bear of a man hauling tubes and rods and clamps, singing softly, building something.

Equipment was scattered on the young sand. Fat white tubes, pieces of some kind of scaffolding, a little electronic gear. What looked like a small refrigerator, a massive metal box, sitting there in the sand casting a long Moon shadow.

'Sergei.'

The singing stopped. The bear figure straightened up, showing no surprise. 'Ah. Dobry vyechir.'

'The Moon - luna - eta ochin kraseeva.'

He could see Kozlov's broad, weather-beaten face split into a grin. 'Very beautiful. I expected you.'

'Yeah.' And somehow, Burdick had expected to find just this: Sergei Kozlov building some kind of rocket, here on an American beach.

Burdick took his gun from his pocket. A Saturday-night special, point 22. He limped forward, over sand that crunched under his feet.

Kozlov looked at the gun. 'Oh, Philip. Kak zhal. That such a weapon should lie between us.'

'What the hell are you doing here, Sergei? This looks like a rocket.'

'It is a rocket. A bath-tub rocket. The heart is a block of sugar, encased in this tubing, my central core and strap-on boosters. Nitrous oxide passes down a hollowed centre, for oxidizer. Fibreglass tubes, and sugar for fuel. A fantasy of small-town America. Workshop rockets into space. Not even expensive. And yet this rocket of mine can reach orbit.'

Burdick kept the gun up. 'Are you crazy? What are you going to do, shoot down the fucking Shuttle?'

Kozlov bent, stiffly, and stroked the white metal box. 'The payload,' he said. 'It is a gene bank. Do you know what that means?'

'No.'

'Spores. Dehydrated. Shielded against the radiation of space. This little capsule will last a thousand years, in its high orbit, protecting its fragile cargo. And then it will drift down to Earth. It has a crude but effective heatshield. Oak, actually, as the Chinese use. The capsule is designed to burst open in the air, releasing its microscopic passengers, to scatter on the wind.'

'Spores? Why? What's the point?'

Kozlov looked up at the Moon, where black-uniformed Americans, volunteers all, were circling and watching, Tom Gibson and Harry Singer amongst them, waiting for this ultimate

demonstration to the world - hell, the solar system - of American competence and will. Kozlov said, 'But didn't your heart lift, as you walked on that ancient landscape?'

'Nothing there but rocks. What use is the Moon, except for this?'

'Undoubtedly, you are correct,' Kozlov said sourly. 'After Sunday Punch, at last we squabbling Asiatics and Europeans and Africans will throw down our arms, shed our centuries of racial and religious division, and accept your cold logic. How right you were never even to attempt to understand us! Perhaps even your own people will accept that logic, beyond the diminishing minority who are protected by these new black-leather police and soldiers of yours. All human problems will be solved, for all time.

'Of course, you are correct. So shoot me now, Philip, for I am only a foolish old man who might endanger your great project. However -'

'What?'

'You have always known,' Kozlov said. 'About the Eagle. The unfortunate incident which destroyed Armstrong and Aldrin, so long ago. Even we could see the truth, through the grimy lenses of the Lunokhod.'

'That there was no bomb.'

'No Soviet sabotage.' Kozlov worked his shoulders. 'A simple malfunction.' 'Yeah…'

The Eagle has landed, Armstrong had called.

Burdick had been in the Viewing Area in back of Mission Control, just a rookie, jammed in with astronauts and brass and dignitaries and relatives, looking out over rows of controllers, just young guys, sweating through their shirts. It was only a few seconds after the landing, and the descent engine had just shut down, up there on the Moon, and most everybody was still cheering Armstrong's words.

But Burdick could see something, in the set of the shoulders of TELMU, the Lunar Module controller.

Pressure and temperature were rising in one of the descent stage's fuel lines. There had to be a blockage in there.

'Frozen fuel,' Kozlov said. 'A slug in a fuel line. Frozen by liquid helium.'

'Yeah. We had to stand there and watch while the engine heat approached the slug.'

The fuel was unstable. It was supposed to be. And when that engine heat reached it, that slug would explode like a small grenade.

The phone lines were open, between the control room and the back rooms and Grumman, the manufacturers out at Bethpage. The Grumman people said to launch immediately in the ascent stage, and leave the problem behind. But the Command Module was in the wrong place for a pickup. Maybe they ought to burp the descent engine, at ten per cent power. But they didn't know if the LM was tilted. If its attitude was wrong it might just topple over.

Indecision.

Okay, said Buzz Aldrin, on the Moon. Okay. It looks like we're venting the oxidizer now. That was all.

The vox loops went quiet, and the telemetry on all the screens turned ratty and dropped out, and that was all there was.

'We couldn't exactly conduct a forensic investigation up there, Harry and me,' Burdick said. 'But -'

'It was just the fuel line. A simple malfunction.'

'Yeah.'

'It was nothing to do with us.' Kozlov smiled. 'We were not so smart, as to be able to reach to the Moon to disrupt your plans!'

Burdick shrugged. 'The lie was simpler. More useful. We were at war, Sergei. I never had a problem with that.'

'I'm sure you didn't. Even though, in a sense, all of this -' he waved a hand vaguely'- is your fault. If only that fuel-line blockage had melted, if only Apollo 11 had turned into the dull triumph it was supposed to be. If only you'd told the truth. But you do not see that. You are a good man, my friend, in your own way. You always did your duty. It has left you as a lonely old man on a wrecked world, but you always did your duty. And now I am asking you to perform a higher duty.'

'Higher?'

'Help me now. We will build this rocket and fire it off together. Two old fools, relics of a Space Age. Together in the last of the moonlight. Humour me.'

'What do we have to do?'

'Assemble the scaffolding. It is a gantry. You see, we are rebuilding Cape Canaveral, here in the radioactive sands of Florida.'

Burdick considered, for long seconds.

He checked his astronaut's Rolex. There were only a couple of minutes to go anyhow.

Burdick picked up tubes of steel, and clamps, and started to figure out how it would all fit together.

They had it half-built when the Sunday Punch went off.

It was a hell of a thing. You could see it, across a quarter of a million miles, the surface of the Mare Imbrium billowing up into space, as the demonstration planet-buster went off beneath it, a quarter of the Moon's grey old face convulsing in an instant.

Much of the material immediately started to fall back into the new crater, a scar glowing yellow-red, but Burdick could see some of it scattering around the rest of the Moon in a huge raying, pounding over those ancient maria. Some of the material dispersed, already cooling, into space.

'So,' Burdick said to Kozlov. 'What do you think?'

Kozlov grinned as he hefted a stabilizer fin. 'Unexpected consequences. The first rocks will be here in twelve or thirteen hours: the big fellows, tumbling into our gravity well, punching through the atmosphere. And a ring will form around the Earth, fat and dense, blocking the sunlight. The temperatures will drop thirty, forty degrees. The ring will hail out slowly, as tektite meteorites. But the ice will last a thousand years. Perhaps a little less, if we are lucky.' He shrugged. 'Something will survive, of course, in the deep rocks and in the ocean ridges. Our capsule carries eukary-otes, multi-cellular organisms -'

'To start the whole damn thing over again.'

'Perhaps they will be lucky: wiser than us, not so wise as you. Come. Help me with this tail section. We have time yet.'

The two of them laboured on, assembling their rocket, two old men moving slowly and stiffly around the beach, as the moonlight turned blood red.