Xeelee: Endurance

  XEELEE:ENDURANCE

  STEPHEN BAXTER

  GOLLANCZ

  LONDON

  Contents

  Title Page

  RETURN TO TITAN

  PROLOGUE

  1

  2

  3

  4

  5

  6

  7

  8

  9

  10

  11

  12

  13

  14

  15

  16

  EPILOGUE

  STARFALL

  REMEMBRANCE

  ENDURANCE

  1

  2

  3

  4

  5

  6

  7

  THE SEER AND THE SILVERMAN

  GRAVITY DREAMS

  1

  2

  3

  4

  5

  6

  7

  8

  9

  10

  11

  12

  13

  14

  15

  PERIANDRY’S QUEST

  CLIMBING THE BLUE

  THE TIME PIT

  THE LOWLAND EXPEDITION

  FORMIDABLE CARESS

  THE XEELEE SEQUENCE – TIMELINE

  ALSO BY STEPHEN BAXTER FROM GOLLANCZ:

  Previous publications:

  Copyright

  It was the fourth millennium.

  Earth was restored. Great engineering projects had stabilised and preserved the planet’s fragile ecosystem: Earth was the first planet to be terraformed.

  Meanwhile, the Solar System was opened up. Based in the orbit of Jupiter, an engineer called Michael Poole industriously took microscopic wormholes – natural flaws in spacetime – and expanded them to make transit links big enough to pass spaceships, enabling the inner System to be traversed in a matter of hours rather than months.

  Poole Interfaces were towed out of Jupiter’s orbit and set up all over the System. The Jovian moons became hubs for interplanetary commerce.

  And Poole and his colleagues pushed further out.

  RETURN TO TITAN

  AD 3685

  PROLOGUE

  The spacecraft from Earth sailed through rings of ice.

  In its first week in orbit around Saturn it passed within a third of a million kilometres of Titan, Saturn’s largest moon, sensors peering curiously down at unbroken haze. The craft had been too heavy to launch direct with the technology of the time, so its flight path, extending across seven years, had taken it on swingbys past Venus, Earth and Jupiter. Primitive it was, but it was prepared for Titan. An independent lander, a fat pie-dish three metres across, clung to the side of the main body.

  Dormant for most of the interplanetary cruise, the probe was at last woken and released. And, two weeks later, it dropped into the thick atmosphere of Titan itself.

  Much of the probe’s interplanetary velocity was shed in ferocious heat, and then the main parachute inflated. Portals opened and booms unfolded, and, more than a billion kilometres from the nearest human engineer, instruments peered out at Titan. Some fifty kilometres up the surface slowly became visible. This first tantalising glimpse was like a high-altitude view of Earth, though rendered in sombre reds and browns.

  The landing in gritty water-ice sand was slow, at less than twenty kilometres per hour.

  After a journey of so many years the surface mission lasted mere minutes before the probe’s internal batteries were exhausted, and the chatter of telemetry fell silent. It would take two more hours for news of the adventure to crawl at light-speed to Earth – by which time a thin organic rain was already settling on the probe’s upper casing, as the last of its internal heat leaked away.

  And then, all unknown to the probe’s human controllers back on Earth, a manipulator not unlike a lobster’s claw closed around Huygens’ pie-dish hull and dragged the crushed probe down beneath the water-ice sand.

  1

  ‘There’s always been something wrong with Titan.’

  These were the first words I ever heard Harry Poole speak – though I didn’t know the man at the time – words that cut through my hangover like a drill.

  ‘It’s been obvious since the first primitive probes got there seventeen hundred years ago.’ He had the voice of an old man, eighty, maybe even ninety, a scratchy texture. ‘A moon with a blanket of air, a moon that cradles a whole menagerie of life under its thick atmosphere. But that atmosphere’s not sustainable.’

  ‘Well, the mechanism is clear enough. Greenhouse effects from the methane component keep the air from cooling and freezing out.’ This was another man’s voice, gravelly, sombre, the voice of a man who took himself too seriously. A voice that sounded familiar. ‘Sunlight drives methane reactions that dump complex hydrocarbons in the stratosphere—’

  ‘But, son, where does the methane come from?’ Harry Poole pressed. ‘It’s destroyed by the very reactions that manufacture all those stratospheric hydrocarbons. Should all be gone in a few million years, ten million tops. So what replenishes it?’

  At that moment I could not have cared less about the problem of methane on Saturn’s largest moon, even though, I suppose, it was a central facet of my own career. The fog in my head, thicker than Titan’s tholin haze, was lifting slowly, and I became aware of my body, aching in unfamiliar ways, stretched out on some kind of couch.

  ‘Maybe some geological process.’ This was a woman’s voice, brisk. ‘That or an ecology, a Gaia process that keeps the methane levels up. Those are the obvious options.’

  ‘Surely, Miriam,’ Harry Poole said. ‘One or the other. That’s been obvious since the methane on Titan was first spotted from Earth. But nobody knows. Oh, there have been a handful of probes over the centuries, but nobody’s taken Titan seriously enough to nail it. Always too many other easy targets for exploration and colonisation – Mars, the ice moons. Nobody’s even walked on Titan!’

  Another man, a third, said, ‘But the practical problems – the heat loss in that cold air – it was always too expensive to bother, Harry. And too risky . . .’

  ‘No. Nobody had the vision to see the potential of the place. That’s the real problem. And now we’re hamstrung by these damn sentience laws.’

  ‘But you think we need to go explore.’ That gravel voice.

  ‘We need Titan, son,’ Harry Poole said. ‘It’s the only hope I see of making our wormhole link at Saturn pay for itself. Titan is, ought to be, the key to opening up Saturn and the whole outer System. We need to prove the sentience laws don’t apply there, and move in and start opening it up. That’s what this is all about.’

  The woman spoke again. ‘And you think this wretched creature is the key.’

  ‘Given he’s a sentience curator, and a crooked one at that, yes . . .’

  When words like ‘wretched’ or ‘crooked’ are bandied about in my company it’s generally Jovik Emry, my good self, that’s being discussed. I took this as a cue to open my eyes. Some kind of glassy dome stretched over my head, and beyond that a slice of sky-blue. I recognised the Earth as seen from space. And there was something else, a sculpture of electric-blue thread that drifted over a rumpled cloud layer.

  ‘Oh, look,’ said the woman. ‘It’s alive.’

  I stretched, swivelled and sat up. I was stiff and sore, and had a peculiar ache at the back of my neck, just beneath my skull. I looked around at my captors. There were four of them
, three men and a woman, all watching me with expressions of amused contempt. Well, it wasn’t the first time I’d woken with a steaming hangover in an unknown place surrounded by strangers. I would recover quickly. I was as young and healthy as I could afford to be: I was over forty, but AS-preserved at my peak of twenty-three.

  We sat on couches at the centre of a cluttered circular deck, domed over by a scuffed carapace. I was in a GUTship, then, a standard interplanetary transport, if an elderly one; I had travelled in such vessels many times, to Saturn and back. Through the clear dome I could see more of those electric-blue frames drifting before the face of the Earth. They were tetrahedral, and their faces were briefly visible, like soap films that glistened gold before disappearing. These were the mouths of wormholes, flaws in spacetime, and the golden shivers were glimpses of other worlds.

  I knew where I was. ‘This is Earthport.’ My throat was dry as Moondust, but I tried to speak confidently.

  ‘Well, you’re right about that.’ This was the man who had led the conversation earlier. That ninety-year-old voice, comically, came out of the face of a boy of maybe twenty-five, with blond hair, blue eyes, a smooth AntiSenescence marvel. The other two men looked around sixty, but with AS so prevalent it was hard to tell. The woman was tall, her hair cut short, and she wore a functional jumpsuit; she might have been forty-five. The old-young man spoke again. ‘My name is Harry Poole. Welcome to the Hermit Crab, which is my son’s ship—’

  ‘Welcome? You’ve drugged me and brought me here—’

  One of the sixty-year-olds laughed, the gruff one. ‘Oh, you didn’t need drugging; you did that to yourself.’

  ‘You evidently know me – and I think I know you.’ I studied him. He was heavy set, dark, not tall, with a face that wasn’t built for smiling. ‘You’re Michael Poole, aren’t you? Poole the wormhole engineer.’

  Poole just looked back at me. Then he said to the blond man, ‘Harry, I have a feeling we’re making a huge mistake trying to work with this guy.’

  Harry grinned. ‘Give it time, son. You’ve always been an idealist. You’re not used to working with people like this. I am. We’ll get what we want out of him.’

  I turned to him. ‘Harry Poole. You’re Michael’s father, aren’t you?’ I laughed at them. ‘A father who AS-restores himself to an age younger than your son. How crass. And, Harry, you really ought to get something done about that voice.’

  The third man spoke. ‘I agree with Michael, Harry. We can’t work with this clown.’ He was on the point of being overweight, and had a crumpled, careworn face. I labelled him as a corporate man who had grown old labouring to make somebody else rich – probably Michael Poole and his father.

  I smiled easily, unfazed. ‘And you are?’

  ‘Bill Dzik. And I’ll be working with you if we go through with this planned jaunt to Titan. Can’t say it’s an idea I like.’

  This was the first I had heard of a trip to Titan. Well, whatever they wanted of me, I’d had quite enough of the dismal hellhole of the Saturn system, and had no intention of going back now. I had been in worse predicaments before; it was just a question of playing for time and looking for openings. I rubbed my temples. ‘Bill – can I call you Bill? I don’t suppose you could fetch me a coffee?’

  ‘Don’t push your luck,’ he growled.

  ‘Tell me why you kidnapped me.’

  ‘That’s simple,’ Harry said. ‘We want you to take us down to Titan.’

  Harry snapped his fingers, and a Virtual image coalesced before us, a bruised orange spinning in the dark: Titan. It hung before Saturn itself, which was a pale-yellow crescent with those tremendous rings spanning space, and more moons suspended like lanterns. And there, glimmering in orbit just above the plane of the rings, was a baby-blue tetrahedral frame, the mouth of Michael Poole’s latest wormhole, a hyper-dimensional road offering access to Saturn and all its wonders – a road, it seemed, rarely travelled.

  ‘That would be illegal,’ I pointed out.

  ‘I know. And that’s why we need you.’ And Harry grinned, a cold expression on that absurdly young face.

  2

  ‘If it’s an expert on Titan you want,’ I said, ‘keep looking.’

  ‘You’re a curator,’ Miriam said, contempt thick in her voice. ‘You work for the intra-System oversight panel on sentience law compliance. Titan is in your charge!’

  ‘Not by choice,’ I murmured. ‘Look – as you evidently targeted me, you must know something of my background. I haven’t had an easy career . . .’ My life at school, supported by my family’s money, had been a saga of drunken jaunts, sexual escapades, petty thieving and vandalism. As a young man I never lasted long at any of the jobs my family found for me, largely because I was usually on the run from some wronged party or other.

  Harry said, ‘Some career. In the end you got yourself sentenced to an editing, didn’t you?’

  If the authorities had had their way I would have had the contents of my much-abused brain downloaded into an external store, my memories edited, my unhealthy impulses ‘reprogrammed’, and the lot loaded back again – my whole self rebooted. ‘It represented death to me,’ I said. ‘I wouldn’t have been the same man as I was before. My father took pity on me—’

  ‘And bought you out of your sentence,’ Bill Dzik said. ‘And got you a job in sentience compliance. A sinecure.’

  I looked at Titan’s dismal colours. ‘It is a miserable posting. But it pays a bit, and nobody cares much what you get up to, within reason. I’ve only been out a few times to Saturn itself, and the orbit of Titan; the work’s mostly admin, run from Earth. I’ve held down the job. Well, I really don’t have much choice.’

  Michael Poole studied me as if I were a vermin infesting one of his marvellous interplanetary installations. ‘This is the problem I’ve got with agencies like the sentience-oversight curacy. I might even agree with its goals. But it doesn’t do what it’s supposed to achieve, all it does is get in the way of enterprise, and it’s populated by time-wasters like you.’

  I found myself taking a profound dislike to the man. Whatever my faults I’m no hypocrite, and I’ve never been able to stomach being preached at. ‘I did nobody any harm,’ I snapped back at him. ‘Not much, anyhow. Not like you with your grand schemes, Poole, reordering the whole System for your own profit.’

  Michael would have responded, but Harry held up his hand. ‘Let’s not get into that again. And after all he’s right. Profit, or the lack of it, is the issue here. As for you, Jovik, even in this billion-kilometres-remote “sinecure” you’re still up to your old tricks, aren’t you?’

  I said nothing, cautious until I worked out how much he knew.

  Harry waved his hand at his Virtual projection. ‘Look – Titan is infested with life. That’s the basic conclusion of the gaggle of probes that, over the centuries, have orbited Titan or penetrated its thick air and crawled over its surface or dug into its icy sand. But life isn’t the point. The whole Solar System is full of life. Life is commonplace. The question is sentience. And sentience holds up progress.’

  ‘It’s happened to us before,’ Michael Poole said to me. ‘The development consortium I lead, that is. We were establishing a wormhole Interface at a Kuiper object called Baked Alaska, thirteen years back, out on the rim of the System. Our plan was to use the ice as reaction mass to fuel GUTdrive starships. Well, we discovered life there, life of a sort, and it wasn’t long before we identified sentience. The xenobiologists called it a Forest of Ancestors. The project ground to a halt; we had to evacuate the place—’

  ‘Given the circumstances in which you’ve brought me here,’ I said, ‘I’m not even going to feign interest in your war stories.’

  ‘All right,’ Harry said. ‘But you can see the issue with Titan. Look, we want to open it up for development. It’s a factory of hydrocarbons and organics. We can make breathable air: nitrogen fr
om the atmosphere, and oxygen extracted from water ice. We can use all that methane and organic chemistry to make plastics or fuel or even food. Titan should be the launch pad for the opening-up of the outer System, indeed the stars. But we’re not going to be allowed to develop Titan if there’s sentience there. And our problem is that, on this world with plenty of biochemistry and primitive life, nobody has established that there isn’t intelligence too.’

  I started to see it. ‘So you want to mount a quick and dirty expedition – incidentally violating the planetary-protection aspects of the sentience laws – prove there’s no significant mind down there, and get the clearance to move in the digging machines. Right?’ And I saw how Bill Dzik, Miriam and Michael Poole exchanged unhappy glances. There was dissension in the team over the morality of all this, a crack I might be able to exploit. ‘Why do you need this so badly?’ I asked.

  So they told me. It was a saga of interplanetary ambition. But at the root of it, as is always the case, was money – or the lack of it.

  3

  Harry Poole said, ‘You know our business, Jovik. Our wormhole engineering is laying down rapid-transit routes through the System, which will open up a whole family of worlds to colonisation and development. But we have grander ambitions than that.’

  I asked, ‘What ambitions? Starships? I read about that.’

  ‘That and more,’ Michael Poole said. ‘For the last few decades we’ve been working on an experimental ship being built in the orbit of Jupiter . . .’

  And he told me about his precious Cauchy project. By dragging a wormhole portal around a circuit light years across, the GUTship Cauchy would establish a wormhole bridge – not across space – but across fifteen centuries, to the future. So, having already connected the worlds of humanity with his wormhole subway, Michael Poole now hoped to short-circuit past and future themselves. That, at least, seemed to be the idea. I looked at Poole with new respect, and some fear. The man was a genius, or mad.

  ‘But,’ I said, ‘to fund such dreams you need money.’