Phase Space

by Stephen Baxter

  – the red of a kid’s blood, toiling in some brutal mountain –

  Slade tried to focus. He felt disconcerted, unsure, vaguely disturbed. His instincts were ringing alarm bells.

  Maybe it was the ship. There had been a shit-load of problems already on this trip. If this was an aircraft he’d get out before taking her up – peer into the vents and kick the tyres – try to back up his hunch.

  But that wasn’t an option.

  Anyhow the others didn’t seem to have noticed anything.

  The meal over, it was time for work.

  Slade toiled steadily through his pre-transposition checklist, throwing switches and recording settings and readings. En route to the Moon, Sun God was still mounted on top of the S-IVB – the spent Saturn V third-stage booster – with its nose pointed forward. Now, to gain access to the Lunar Module – still housed within its adapter cone at the top of the booster – CM Pilot Pond had to uncouple Sun God from the stack, turn it around, and dock it nose-to-nose with the LM, the Lunar Module.

  Pond called out a countdown.

  Slade heard a muffled thump, a soft push at his back.

  Sun God had become detached from the depleted S-IVB booster stage. Pond fired up the reaction-control system, and let Sun God drift away from the booster –

  ‘Uh oh,’ Pond said. ‘I got a twelve-oh-two alarm.’ This was a computer programme alarm, flashing up on Pond’s display unit. ‘Something to do with a memory overload. It came up when I engaged the rendezvous radar. And it – shit.’

  The alarm code had changed to ‘twelve-oh-one’.

  ‘Houston, are you copying?’

  ‘Stand by, Sun God. We’re working on it.’ The capcom’s voice betrayed nothing.

  Slade snorted and slammed the palm of his hand against the computer. One little glitch and the docking was on hold.

  There was nothing he could do now but wait. And all the time, Slade knew, Sun God, on its separate trajectory, was drifting farther from the S-IVB; already the gap had opened up to two miles. To recover now they’d have to go through a full-scale rendezvous procedure.

  – and still he had that sense of dislocation: of things being not quite right. As if an engine was running off –

  Slade was beginning to think his mission might be snake-bit: doomed to failure. They had had problems with the Apollo since they left the ground. Lousy comms. Computer glitches. Foul stenches from the life support. Scuffed wiring. Stuck hatches. Inoperative reaction-control thrusters.

  Slade had followed the evolution of his ship through its manufacture. He had seen the NASA QA report that had called it sloppy and unsafe. He knew there had been twenty thousand failures during its construction and testing. He knew it was just a lousy bucket of bolts that should never had left the factories, at Palmdale and Bethpage.

  But here was Slade flying this clunker to the Moon, because that was the timetable of America’s mad, impetuous dash into space, and Slade would have been aboard if he had to get out and push.

  It was six years since Slade’s first flight in space. He’d finished three orbits of Earth on the second orbital Mercury flight, in 1961, following John Glenn. He’d hung in there, piling up flight assignments, while younger, smarter guys came into the programme to compete with him. He’d gotten a Gemini flight, and a seat on the first Earth-orbital Apollo test flight in 1966. He was the only man to have flown all three generations of US spacecraft.

  And now here he was – commander of his own lunar ship – on his way to the ultimate piloting test, the Moon landing itself. This would be the best of all, a full-up mission, the crown of his career.

  But it seemed to be falling apart.

  The capcom came back on the air-to-ground loop. The only solution Houston could come up with was to run the rendezvous manually. ‘The coordinates are NOUN 33, 092, 29, 43532 minus 00312. HA and HP are NA. Pitch is –’ Slade wrote out the data on the back of a checklist, and read them back down the link.

  Pond and Slade rattled through a brief start-up checklist, and Pond began to throw switches. Bado was appointed timekeeper, and he counted Pond down to the time indicated by Houston.

  ‘Ten, nine, eight –’

  Now, framed in the windows, Slade could see the S-IVB. It was a white-painted cylinder, dappled with black panels, the brave scarlet ‘USA’ emblazoned on its flank. And there, at the nose of the cylinder, was the complex, foil-covered roof of the Lunar Module, now exposed to the sunlight, its docking receptor a dark pit at its centre.

  The next item was a couple of short SPS burns, thrusts of the Service Module main engine.

  ‘Three, two, one,’ Bado said. ‘Fire.’

  There was a brief thrust, of perhaps a half-G, which pressed Slade into his couch. It lasted just seconds.

  Pond had to fly by eye. The rendezvous radar was still useless. The S-IVB seemed to approach them, then recede, then approach again; it was like stalking some huge, cautious animal.

  At last, the S-IVB was looming before them, huge and ungainly and complicated, the LM nestling in its nose. The windows were filled with drifting metal struts and paintwork.

  Shadows mingled. The cabin shuddered as Sun God impacted the LM, hard, and there was a groan of metal.

  A green light came on. Slade heard the rippling clang of docking latches snapping shut.

  ‘How about that,’ Pond whooped. ‘Houston, virgin no more.’

  Thank Christ, Slade thought. Thank Christ –

  But now there was something else. He could smell something.

  Smoke.

  There was smoke coming from a compartment at the foot of his couch. Maybe there was some new piece of scuffed wiring, shorting down there, some piece of equipment to do with the docking. And now there was a flare of light; it looked as if a spark had caught the nylon netting underneath their couches.

  It spread quickly.

  Christ, there was fire everywhere.

  Velcro pads stuck to the walls just exploded into flame and dropped away, showering them with sparks. Even materials that were normally flameproof were burning as if they had been dunked in kerosene: checklists, insulation, aluminium, the fabric of his suit.

  Even the skin on his hands.

  It was pure oxygen in here, at five psi.

  Oddly, there was no pain. And he could still smell that smoke. The double-domes said Moon dust would smell like that, like ash –

  He had a crushing sense of unfairness. He was going to lose his mission, the full-up flight he’d intended. It was all meaningless, like another crashed simulation.

  Slade remembered so much: his father, Fay and the girls, the ranch house in Clear Lake. Such memories comprised him, his soul. But in a moment the memories would be gone. As would he.

  He felt a rush of warmth, within him. His thoughts seemed to soften, guttering like candle wax.

  Slade tried to focus on Fay. But he could no longer remember her face.

  The air was full of light.

  Red light.

  Empty, its systems dormant, the glowing Apollo sailed on, towards the brick-red Moon …

  … the Moon over which I sailed, in triumph! For my hypothesis was confirmed.

  And in the destiny of these stunted creatures there is a profound lesson for our own future.

  The First World formed deep in the hostile maw of the new sun’s gravity well. It is a ball of rock.

  But our Home, at a comfortable distance from the sun, was born half rock, half ice. A giant among moons, its huge mass caused it to heat as it collapsed. The primordial ices were melted and vaporized. The rock settled to the centre. Thus, Home is a ball of silicate, overlaid by a shell of water ice.

  Home’s first ocean was a mixture of ammonia and methane. A dense methane-water-ammonia atmosphere was raised over that ancient sea. The new world was a cauldron, with air pressure hundreds of times its present level, and searing temperatures.

  And in the organic soup of the ammonia-water ocean, complex chemistry seethed …

&n
bsp; Life arose. Yes, so long ago, at the dawn of the solar system itself!

  But the new ocean and atmosphere were not stable. Ultra-violet flux from the young sun beat down on the atmosphere, shattering its ammonia molecules; planetesimals continued to fall, blasting away swathes of Home’s atmosphere; the atmospheric gases dissolved in the ocean …

  Perhaps, in the brief time they were allowed, those primeval life forms reached a high degree of complexity. We cannot tell. But they could not survive these changes. All we can find are chemical fossils, the decomposed elements of a life that was snuffed out as Home settled into its billion-Revolution Freeze. Home was a world of darkness, of haze and clouds, of sticky organic slush: a land of mud and crater lakes – a world utterly alien to the clement orb which sustains us now!

  After the time of the hydrous First-Worlders, the evolution of Home continued.

  As the sun brightened, at last the Freeze receded. The ethane lakes boiled, evaporated. The gases trapped there – nitrogen, methane, hydrogen – exsolved, thickening the atmosphere. Eventually the ice shells over the magma, the ancient ammonia oceans, melted, exposing the old seas once more. Ammonia and water vapour enriched the air still further …

  And life, after its epochal suspension, began to stir once more. After hundreds of millions of Revolutions, our true history had begun.

  But Home, too, is under threat of destruction!

  Even now, our air is leaking away; for our world is fundamentally too small to retain its thick atmosphere even at today’s prevailing temperatures. And we can postulate a time when the rising temperatures caused by the sun’s expansion will once more cause the loss of our air, the evaporation of our ammonia oceans.

  But the sun’s ballooning growth will not stop there. When the red giant growth reaches its climax, even our bedrock water ice will become liquid.

  Think of that! We have used water ice as the staple of our structures: the cities, the spires, the gleaming bridges. When the ice softens, our buildings will collapse.

  Worse: our very bones will melt!

  And, at last, even the water will boil away … It will take only a few thousand revolutions, no more. Then, nothing will be left of Home but its rocky core.

  Long before then, we will be forced to make a choice: to submit to extinction, or to flee Home. We have millions of Revolutions before us, of course. Some argue that is enough. I say that when the destiny of the species is at stake, only eternity will suffice!

  … But let us draw back, from the end of Time itself.

  Before the final destruction, for a brief period, Home will have new lakes and oceans – but of liquid water.

  That is why we should cherish the hydrous Astronauts, these silent ambassadors of the past. That is why we should endeavour to reconstruct them, to revive and study them.

  For one day the circle of destruction and birth may close. One day we may be forced to share Home – with them!

  … But I digress.

  My historical reconstruction complete, I froze the simulation.

  In the light of its Moon the little, glittering ship was really quite beautiful. So shiny and new, silver and white and black. Like a toy. But so lethal, of course.

  How entertaining it had been. The interplay, the language. So authentic! And so ingenious. The very idea of reassembling the craft by hand, here in cislunar space!

  To impose such defects seemed hardly fair. But this was not a game. Fairness was not a factor. Given this level of gadgetry, even multiple defects must have been common.

  Of course, it might not have been quite like this. Perhaps more sacrifice was necessary. If that oxygen fire had occurred before a launch, for instance, subsequent generations of spacecraft might have been rebuilt for greater safety. The beings who performed these flights did not think logically, in an orderly fashion. Logically, they should never have flown into space at all! Perhaps they needed some such catastrophe as this to occur, regularly, to guide them on their path.

  But it was really quite remarkable. These hydrate creatures were really not up to this. Not yet; perhaps, in the end, not ever. They just were not smart enough. Why, they must even have navigated by eye, by the stars! And yet they persisted. There was something to admire, in this grandiose, doomed enterprise.

  Well, I felt tired but happy. My simulations had converged. A mission to the Moon with chemical rockets, so I had proven, was foolish but feasible, given supportive historical logic. Already I had sufficient documentation; it was not necessary to adjust the parameters once more, to follow the sequence through to its conclusion.

  I could allow the simulation to dissolve.

  Yet I lingered.

  I basked in my triumph.

  But I felt –

  Complicated.

  Guilty?

  Perhaps. Those simulacra were fully sentient, of course. It was necessary for verisimilitude.

  But in the end they were distressed. Well, of course they were distressed. Believing their world to be real, their lives and memories to be genuine, they had undergone a cessation of consciousness. Still, I meant to honour them – their ingenuity and bravery – not cause them harm.

  Perhaps, I reflected, I should reconsider. Complete the exercise.

  But after all, they were only simulacra.

  Yes. Only simulacra. But of beings who once took halting steps in Moon dust …

  … Moon dust which seemed to crunch beneath Slade’s feet, like a covering of snow. His footprints were miraculously sharp, as if he’d placed his ridged overshoes in fine, damp sand. He took a photograph of one particularly well-defined print; it would persist here for millions of years, he realized, like the fossilized footprint of a dinosaur.

  Or, he thought vaguely, not.

  He felt dreamlike.

  He was floating over this bright landscape. The tug of gravity was so gentle he couldn’t tell which way was vertical. And when he closed his eyes he saw things: a bleeding boy, a bitter old man, a fire –

  It was probably the low G. Yeah, that was it. The low G.

  He looked around.

  The LM, standing in a broad, shallow crater, was a glistening, filmy construct of gold leaf and aluminium. Low hills shouldered above the close horizon. There were craters everywhere, ranging from several yards to a thumbnail width, the sunlight deepening their shadows.

  Bado came loping out of a shallow crater, towards Slade. Bado had one glove up over his chest, obscuring the tubes which connected his backpack to his oxygen and water inlets. His white oversuit was covered in dust splashes. His gold sun visor was up, and inside his white helmet Slade could see Bado’s face, with its four-day growth of beard.

  Bado said, ‘Hey, buddy. Look up.’

  Slade tipped back on his heels and looked at the sky.

  The sky was black, empty of stars. In the middle of the sky the Earth was a fat crescent, four times the size of a full Moon. And there, crossing the zenith, was a single, brilliant, unwinking star: the orbiting Sun God, with Pond, their Command Module Pilot, waiting to take them home.

  It was July, 1969.

  Holy shit, Slade thought. I really am here. I made it. Holy shit.

  He felt a rush of affection for his buddy, the glowing reality of him, here on the Moon. Those fragmentary visions fled, leaving him with a sense of here and now and rightness.

  This was his place. This was where he was meant to be.

  He tilted forward and eyed Bado. ‘Pretty sight. But we got to hustle, boy; we got a fat checklist to get through. We’re going for a full-up mission here, and don’t you forget it.’

  Through his visor, Bado grinned. ‘Yes, sir!’

  SUN-CLOUD

  To human eyes, the system would have been extraordinary:

  The single, giant sun was so vast that its crimson flesh would have embraced all of Sol’s scattered planets. Across its surface, glistening vacuoles swarmed, each larger than Sol itself.

  There was a planet.

  It was a ball of rock no lar
ger than a small asteroid. It skimmed the sun’s immense photosphere, bathed in ruddy warmth. It was coated with air, a thick sea.

  The world-ocean teemed with life.

  Beyond the sun’s dim glow, the sky was utterly dark.

  She rose to the Surface. Thick water slid smoothly from her carapace.

  She let her impeller corpuscles dissociate briefly; they swam free of her main corpus in a fast, darting shoal, feeding eagerly, revelling in their brief liberty.

  She lifted optically sensitive corpuscles to the smoky sky. The sun was a roof over the world, its surface pocked by huge dark pits.

  She was called Sun-Cloud: for, at her Coalescence, a cloud of brilliant white light had been observed, blossoming over the sun’s huge, scarred face.

  Sun-Cloud was seeking her sister, the one called Orange-Dawn.

  Sun-Cloud raised a lantern-corpuscle. The subordinate creature soon tired and began sending quiet chemical complaints through her corpus; but she ignored them and waited, patiently, as her sphere of lantern light rolled out, spreading like a liquid over the oleaginous Surface.

  The light moved slowly enough for a human eye to follow.

  Sun-Cloud’s people were not like humans.

  Here, people assembled from specialized schools of corpuscles: mentalizers, impellers, lanterns, structurals, others. Obeying their own miniature imperatives of life and death, individual corpuscles would leave the aggregate corpus and return to their fish-like shoals, to feed, breed, die. But others would join, and the pattern of the whole could persist, for a time.

  Still, Sun-Cloud’s lifespan was finite. As the cycle of corpuscle renewal wore on, her pattern would degrade, mutate.

  Like most sentient races, Sun-Cloud’s people sustained comforting myths of immortality.

  And, like most races, there was a minority who rejected such myths.

  Sun-Cloud returned to the Ocean’s deep belly.

  The light here was complex and uncertain. Above Sun-Cloud the daylight was already dimming. And below her, from the Deep at the heart of the world, the glow of a billion lantern-corpuscles glimmered up, white and pure.