Ark

by Stephen Baxter

He stepped back deliberately. ′Don′t cry, baby.′ His voice was muffled.

  Kelly Kenzie ran up and grabbed her arm. ′You still here? Come on, damn it, that fucking bus is going now.′

  Holle let herself be pulled away. When she looked back, Patrick had deliberately lost himself in the crowd.

  They crowded onto the armoured bus. It rolled away before Holle had a chance to sit down, before the door was properly closed. Everybody was stumbling around, dragging their bags, their suits half zipped up; this was nothing like the orderly embarkation they had rehearsed.

  Holle got to a seat, but it was too small for her, padded up as she was in her layered suit. Bad design, she thought. Make a note for the integration oversight committee. But this bus would be vaporised in a couple of hours, poorly designed seats and all. She felt a hysterical giggle bubble up. She looked out of the window. Brown, greasy smoke from the oil fire in the moat rose into the air, as it had for six days now.

  A dull roar reached a crescendo that crashed down, making them all duck. Two fighter jets screamed across the sky, their lights bright, burning up a bit more of the nation′s dwindling store of aviation fuel. She wondered what threat they had been sent aloft to face.

  The bus lurched to a stop. The driver opened the doors, and stood up and waved her arms. ′Out! Out! Move it!′ She was a middle-aged woman in an NBC coverall, for nuclear-biological-chemical protection. Holle understood her urgency; if the driver didn′t get her bus turned around and out through the blast zone, she wouldn′t survive the launch, NBC suit or not.

  Holle got off the bus, clutching her bag. The Ark towered above her, gleaming in a bath of light cast by the powerful floods at its feet. Tanker trucks were pulled up at the ship′s base, their hoses snaking into the superstructure, while far above her head valves vented white vapour.

  There was no time for reflection. Kelly hurried ahead, and Holle followed, clutching her bag.

  They got to the foot of the boarding ramp, where ground crew and military, all in NBC suits, checked their boarding tokens and rushed them through retinal checks. One last security check, the last of all. Kelly and Holle got through and joined the line leading up the sloping ramp into the maw of the ship.

  And then it struck Holle. ′Hey,′ she said, panting. ′I just took my foot off the Earth for the last time.′

  Kelly was striding hard, working the big, deep stairs like an athlete in training. ′You need to focus, Groundwater.′

  Holle hurried after her. ′These moments are unique. I don′t believe this is happening this way.′

  ′You′ve got years to believe it. Come on.′

  The line slowed as they neared the hatch, some twenty metres above ground level. People jostled as they tried to board. From this vantage Holle could see further out, across the Zone with its frantic activity to the rising curtain of ugly oil smoke, and the terrain beyond. The lights of Gunnison were bright in the dark of a December evening, and plumes of smoke and dust rose up across the wider Hinterland. Over the hiss of the Ark′s giant valves she heard the popping of small-arms fire, the crump of heavier munitions, and, she thought, distant screams. The Ark was the centre of a war zone. It was impossible to believe that everything she saw from up here was going to be destroyed as soon as the Ark′s extraordinary engine fired up. But beyond the human sprawl the Rockies rose up, huge and impassive, dark against the sky. They would withstand even the launch of an Orion. She wondered if Earth II would have mountains.

  She was approaching the hatch. She took one last deep breath of the air of Earth, but it tasted of gasoline, and the ammonium of the piston coolant, and the harsh metal tang of the Ark′s multiple hulls.

  And now she heard shouting from down below. She glanced back. The security barrier at the base of the ramp was failing. Some of the military seemed to have mutinied, and were fighting with cops and ground crew, trying to get on board the ship themselves. Everything was dissolving, she thought.

  More planes roared over, impossibly low. She ducked, and hurried inside the ship.

  41

  The leak is here.′ Liu Zheng unfolded a big paper schematic, and with a pointing finger showed Matt a feed leading from a secondary coolant reservoir. His hand was gloved; they both wore lightweight NBC suits. He had to shout to make himself heard over the hiss of vapour, the roar of engines as buses and trucks raced around the base of the Ark, the urgent yelling of voices, and an ominous clatter of gunfire. ′See? Just above this O-ring.′

  ′Why can′t the automated systems handle it?′

  ′They froze,′ Liu said. ′A multiple failure. Shit happens. Well, that′s why we′re here. The leak has to be fixed; without coolant, if one of those suspension pistons overheats and seizes in flight, the Ark will fall out of the sky. You have your tools?′

  Matt hitched a pack on his back.

  ′OK. Take elevator three.′ Liu grinned. ′This is your moment, Mr Weiss.′ He stuffed the schematics into Matt′s pack. ′Go, go!′

  Matt ran to the elevator cage, one of a dozen that allowed access to the Ark for maintenance. He slammed shut the gate and grabbed the dead man′s handle that sent the cage rising up into the shadowed innards of the ship. He rose past the curving flank of one of the crew hulls. A wall of white insulation blanket rushed past his face, pocked with maintenance hatches, safety warnings, valve sockets - and handhelds, labelled with upside-down stencils, for use by spacewalking astronauts in the extraordinary future when this ship would be taken apart at the orbit of Jupiter, and reassembled for interstellar flight. He felt light-headed, unreal. He hadn′t slept much in the last week. Since his liberation from gaol a week ago he had dedicated all his time to memorising every aspect of the systems to which he was going to be assigned. He figured he could catch up on his sleep when he was dead. And with the Ark launch being brought back, he had, of course, suddenly lost twelve hours of his life. Quite a big percentage when you only had a day left anyhow.

  He looked up, trying to spot the problematic feed. The Ark′s interior was as brightly lit as the exterior, a mass of gleaming metal, pipes, vast tanks connected by ducts and cabling, all contained within the mighty struts of the frame. He saw cameras swivelling, and, clambering over the wall of one of the big crew hulls, a maintenance robot, a thing like a spider armed with a camera for a head, sucker feet so it could climb vertical walls, and a waldo arm with a Swiss Army knife selection of tools.

  Still rising, he looked down the flank of the crew hull, and saw, down below, through gaps in the cluster of tanks and pipes, the impassive bulk of the pusher plate itself. An inverted dish of hardened steel, it was itself a beautiful piece of engineering, forty metres across and just ten centimetres thick. The bombs would be detonated below the plate, a weapon five times the strength of the Hiroshima bomb detonating one every one and one tenth of a second. The bombs would be fired into place by the simplest method imaginable, by shooting them down out of a cannon set square in the middle of the pusher plate. The propellant produced by each pulse unit would bounce off the pusher plate, transferring momentum but evaporating too quickly to damage the plate, which would be further protected by a screen of anti-ablation oil, constantly renewed. The resulting thrust would be soaked up by the shock absorber system, immense pistons that rose up above his head, each with a stroke of eleven metres and with a complex dual action that protected the vulnerable parts of the ship from rebound in case a pulse unit failed.

  After studying the technical issues from scratch themselves, the Ark′s designers had reverted to something close to what had become the standard design for much of the duration of the original Cold War Project Orion: a four-thousand-tonne brute with that mass split evenly between the pusher plate, the ship′s structure, the bombs, and a full thousand tonnes of payload. By comparison the Saturn V, the booster that had launched Apollo to the moon driven by chemical energies alone, had weighed in at three thousand tonnes, of which only forty tonnes was payload. It was hard to grasp the reality, even now. When the shi
p was in flight this whole space would be the scene of huge engineering activity, with splashes of blinding atomic glare coming from all around the rim of the pusher plate, and those pistons shuddering with each mighty stroke.

  Looking up now, Matt could see he was approaching the huge tanks of coolant fluid and ablation oil suspended in their frame, and the complex network of pipes that connected one to the other. That was where his leak was. In flight, an ammonia compound was used to cool the pistons after each stroke. The resulting high-temperature compressed gas was then used to power the pumps that squirted a sheet of anti-ablation oil out over the pusher plate before the next detonation, and to thrust the next pulse unit from the charge magazine. Using the products of one stroke to prepare for the next was pleasing for an engineer, a process that reeked of thermodynamic efficiency. But that complexity led to many failure modes.

  The light in his elevator cage died, and the cage jolted to a halt.

  ′Shit.′ Matt squeezed his dead man′s switch, and rattled at the cage door. All power to the cage and the pulleys that had been hauling it had been lost. Matt flicked a microphone at his throat. ′Liu, it′s Matt.′

  As the link came active, Matt heard Liu Zheng break off another conversation. ′Go ahead.′

  ′I lost power, in number three elevator.′

  ′Wait… I can see. We lost power all down that side, a generator broke down. Damn.′ Liu sounded desperately tense. What they feared above all was multiple failure, one problem compounding another. ′You still on that coolant leak? You fixed it yet?′

  ′Negative.′ Matt resisted the urge to snap; of course he hadn′t, in the couple of minutes since he′d left Liu′s side. Liu was juggling a hundred tasks simultaneously, all as urgent as Matt′s; time must be stretching for Liu, in this last hour of his life. ′I′m still on my way up.′

  ′We can′t get power back until - I don′t know. Matt, can you improvise? Yes, Mary, what is it? …′

  Matt snapped off the comms link. Improvise. Well, there was no choice, and there were access ladders fixed all over the ship.

  He fixed his tool pack on his back, grabbed the manual handle, and hauled the gate open. The nearest ladder was just outside the cage, and there was a rail to which he clipped a safety attachment to his belt. He got hold of the rail, swung out one foot, and reached the nearest rung. He tugged the safety harness to test it. Then he looked up into the cathedral of gleaming metal forms above him, and began to climb.

  As he passed, monitor cameras swivelled to track him.

  42

  From the ramp, Holle followed Kelly across a mesh floor and through a brightly lit chamber, before they joined yet another line for access to the higher decks.

  Holle looked up through layers of flooring. This crew hull was an upright cylinder. In fact the hull was a remodelling of one of the big propellant tanks of the Ares V booster, and a relic of the project′s dysfunctional design process; when the decision was made to scrap the use of Ares boosters and fly with Orion, the engineers had scrambled to make use of the components of the abandoned Ares technology. The hull was divided into decks by mesh panels that could be disassembled to open up the interior space. For now the decks were set out with the crew′s fold-out acceleration couches. Down through the centre of the mesh flooring came a pole, like a fireman′s pole. One by one the crew were climbing metal rungs bolted to the pole′s side.

  They reached that central ladder. Kelly went up first, Holle following, climbing up through the hull.

  The hull′s interior architecture was modelled on what had been proven to work on the space station, with colour schemes and lighting strips designed to help you orient yourself in zero gravity, and a variety of fold-out stores, workstations and consoles. There were Velcro pads and handholds everywhere, in readiness for freefall. For now the only important functionality was on the twin bridges, situated in the nose of each crew hull, and the workstation screens all showed the impassive, reassuring face of Gordo Alonzo, with a blurred view of the Pikes Peak launch control centre behind him, and a countdown clock.

  But Gordo′s voice was drowned out. On each deck there was chaos. People were in the couches, tightening their harnesses and plugging in comms and waste systems. But Holle saw others arguing over seats, waving tokens in each other′s faces. While most people were in standard-issue flight suits as she was, a significant number weren′t. She didn′t even recognise a good number of the people on board.

  She called up to Kelly, ′Where′s security? How the hell did these people get aboard?′

  ′Doesn′t matter,′ Kelly called down, climbing the ladder as determinedly as she′d climbed the ramp. ′There is no security any more, Holle, not in here. It′s up to us now. We′ll sort it out in space. This is your deck, right?′

  ′Yes.′ Kelly had to go on to the bridge. ′Have a good trip, Kel.′

  Kelly grinned, exhilarated, fearless. ′This is what I waited all my life for. You bet it will be a good one. See you beyond the moon.′ She clambered on, heading up out of sight, while Holle stepped off the ladder.

  She found her own couch easily enough, one of an empty pair. Your couch was numbered to match your boarding token. The couch was a simple foldaway affair of plastic and foam, but it had been moulded to the shape of her body, and she′d got used to it in training; she settled into it now with relief, and tucked her pack into the space underneath.

  She saw Theo Morell, the general′s son, trying to climb down the fireman′s pole, moving in a different direction from everybody else, in a coverall too big for him. Holle called over. ′Theo. Hey, Theo!′

  He looked around, confused by the noise. Then he saw her and came over hesitantly. ′Holle?′

  ′You look lost.′

  ′Somebody′s in my couch,′ he said miserably. ′Up on Deck Nine. I showed her my token, the number on it, but she just said—′

  ′Never mind.′ She looked at his anguished face. She ought to hate him; he had taken Mel′s place. ′Here. Take this one, beside me.′

  ′But it doesn′t match my number.′ He dug in his pocket. ′I have the token—′

  ′Things have got a bit chaotic. Just sit down, strap in, and if whoever has the number for that seat comes along - well, we can deal with that when it happens. Look, put your pack under the couch. You have your pack, don′t you?′

  ′I lost it,′ he said. ′I got knocked off the pole.′

  ′God, Theo, you′re a clown. Well, you′ve got years to find it before we get to Earth II. Just pray it doesn′t hit somebody on the head when we launch. Come on, sit down and strap in.′

  Hesitantly at first, but then with relief, he obeyed her and clicked home his harness. They were lying on their backs, as if in dentists′ chairs, staring at the deck above. Somewhere above their heads, the noise of an argument over a couch grew louder.

  43

  Don Meisel took Mel′s arm and pulled him out of the line for the passenger buses that would have taken him out of the blast zone. Don was in combat gear, wearing a heavy bullet-proof vest and carrying an automatic weapon. Under his helmet his face was smeared with dark cream, but it was streaked by sweat on his forehead and under his eyes. ′You up for a little action?′

  ′Are you serious? I haven′t fired a gun in years.′

  ′We need everybody we can get. Although you fly boys never could shoot straight anyhow. Come on.′ He set off jogging towards a big, blunt-nosed military truck in bottle green.

  Mel had to wait as a bus roared past him, heading down the heavily reinforced corridor away from the Candidate Hilton and out of the blast zone. Then he followed helplessly.

  ′So,′ Don asked as he jogged, ′you see Holle off?′

  ′I chickened out,′ Mel admitted. ′Seeing her through a wall of glass - what difference would it have made?′

  ′Fair enough,′ Don said, jogging. ′Best to keep busy.′

  ′So what′s going on?′

  ′Action all around the perimeter. Here.�
� There was a heap of armour and weaponry by the truck; Don handed Mel police body armour, helmet and gun. ′They′re coming in worse from the west just now. We think it′s an abider faction. But it′s hard to tell, everything′s mixed up to hell with eye-dees and rogue elements of cops and military and National Guard running around everywhere. You strapped up? All aboard.′ He helped Mel climb up onto the bed of the truck.

  There were maybe twenty troopers jammed in here, cops and National Guard and regular army troops. An officer tied up the tail-board, and they rolled off, heading west, with an engine roar and a plume of dust rising up into the evening dark. The truck followed a trail of white rags tied to sticks, evidently leading it through a minefield.

  Don stared straight ahead. Mel couldn′t judge his mood. ′So - you OK with everything? The launch and stuff.′

  Don forced a smile, and adjusted his chinstrap. ′As much as you′d expect. We′d both rather have sent Dexter, but they ain′t taking two-year-olds. Kelly′s gone on our behalf, to live on a new world as we′ll never be able to. As for me, what the future holds God only knows. At one time I had a career path, you know. Worked in the city, in a CAPs squad under an officer called Bundy. Good man.′

  ′CAPs?′

  ′Crimes Against Persons. Homicides and assault. It was regular police work. And I was smart. I was thinking of going into Special Investigations. It was compensation, you know, for being thrown out of the Academy. But we kept being pulled out to go man some barricade or other, or break up another food riot at another eye-dee camp. Now it′s all kind of liquefying, and so much for my career plans.′ He looked at Mel. ′But there′s still work to be done. If you like I′ll put in a word, and - hey, we′re there.′

  The truck growled to a stop. The officer let down the tailgate, and the troopers clambered down. There was a sound of gunfire, a stink of burning, a pall of smoke.

  Don beckoned to Mel. Stick with me. They made their way across broken ground, the smashed foundations of some building. The gunfire, the shouting and the screams, got louder. I should be on the Ark right now, Mel thought. Not here.