Xeelee: Vengeance

by Stephen Baxter

  ‘Maybe. You start.’

  Harry sighed. ‘Wise-ass kid. Well, in the last few months we all studied military strategy pretty hard, from the history books. And we’ve been tutored by a few entities like Gea, some of whom are old enough to have witnessed some of the Anthropocene and Bottleneck wars.

  ‘We think we have the Xeelee’s trajectory pretty much mapped out now. It’s been a long haul in from Mars – it doesn’t seem to do anything quickly, does it? – but now it’s clearly closing in on Earth. So we have set up three stop lines, as we’ve called them. Three locations we’re going to try to hold the Xeelee. The first is here, close to L5. With the Xeelee two months out from Earth.’

  ‘You’re going to try to hit the Xeelee here? What with?’

  ‘You’ll see soon enough. Don’t spoil my surprise. The next stop line is ten light-seconds from Earth, roughly. Three million kilometres; a day’s transit to Earth for the Xeelee. If it gets that close we’re going to hit it with all we’ve got left, from kinetic-energy weapons to fission and fusion bombs to GUTengine missiles—’

  ‘We tried that stuff at Mars. Did no good there. What makes you think it will work now?’

  ‘This will be an assault on a much larger scale. Mars was remote, Michael; it was impossible, politically as well as logistically, to move all our assets over there. And besides, we still didn’t understand the Xeelee’s capabilities at that point; for all we knew it might have worked. Now we can throw in everything. We may yet exhaust the Xeelee’s capacity for punishment; we may just burn the thing down. We certainly have to try – but if the Xeelee does break through that second stop line, it will be just a day out from Earth.’

  ‘You said there’s a third stop line.’

  ‘It’s kind of arbitrary. We defined it as one light-second from Earth. That’s about the Moon’s distance. A psychological barrier, you see. But only a few hours out, for the Xeelee.’

  ‘And you’ll be defending that line with—’

  ‘You.’ He eyed Michael. ‘Your weapons from Gallia Three. Whatever you’ve got. And however we can back you up. Look, we have our eyes and our ears. We know you have some pretty impressive work going on out there at Gallia, though we haven’t been able to get hold of the results in detail.’ He held up a hand. ‘Don’t tell me. But if you think this system might work against the Xeelee—’

  ‘Highsmith Marsden thinks it might.’

  Harry smiled ruefully. ‘That screwball loner? Well, there you go, humanity is saved.’

  ‘This was why we kept it discreet, Harry,’ Poole said, annoyed. ‘So there’d be no scepticism, no second-guessing. We knew this was the best we could do – the best anybody had. We couldn’t afford a loss of focus. And that’s why we insist on the final say in the system’s deployment.’

  Harry held up his hands. ‘Look, Michael, if you have faith in your system, I trust your judgement. Well, I’ve no choice. But – work with us. Put your ships on the lunar-orbit stop line. We’ll stand with you, with whatever we have left, whatever we can do. Even if it’s only to distract the Xeelee for a few seconds.’

  Michael considered that. ‘Seems reasonable.’

  Harry nodded, looking more grim than relieved. ‘OK. We’ll get our staffs together to talk and work it out.’

  ‘I don’t have any staff. Talk to Nicola Emry. She flew in with the Gallia crews.’

  ‘That mouthy kid?’

  ‘Harry—’

  ‘OK, OK. Whatever you say. Now, look, Michael, I’ve one more question for you. I am your father – I am the Steward of Stewards – and I want you to do me the courtesy of answering. However briefly. Will you do that?’

  ‘Ask.’

  ‘Suppose we fail. Suppose the Gallia stuff fails. Do you have anything else?’

  Poole considered. Was it more productive to lie at this point, or to tell the truth? That was the kind of calculation Harry would make, he realised. Maybe he had more of his father in him than he sometimes liked to believe.

  ‘Michael?’

  ‘Sorry. Yes. I have something else.’

  Harry held up his hands. ‘A supplementary, OK? You don’t want to tell me what this is?’

  ‘No.’

  Harry considered that. ‘Fair enough. I guess that if we get to that point, it won’t make much difference if the Xeelee wrecks the Earth or you do.’

  Poole sat silently. That was unfortunately evocative of his own fears.

  ‘I’m trying to tell you,’ Harry said heavily, ‘that I trust you, son. I know you’ll do your best. I’ll keep your secret. Because at least I’ll know that if all else fails—’

  Light flared, at the centre of the big viewscreen.

  Poole stood and stared at the image, at light that was already quickly fading. Fragments dispersing as if from some immense explosion.

  Data started to chatter in, scrolling across the secondary softscreens. ‘What in Lethe—’

  ‘The Xeelee,’ Harry said. ‘Well, it crossed the stop line. And we hit it, right on cue. I got too interested in our conversation; I lost track of time.’

  Poole remembered the speck of light he’d seen drifting close to the Xeelee. ‘Hit it with what?’

  ‘Cruithne,’ Harry said grimly. ‘You heard of that? Earth-crossing asteroid, co-orbiting with Earth. Our second moon, some called it. Stealthed as best we could, arrays of GUTdrives fixed to its surface. We’ve had it sailing out this way for months; it should have looked like it was going to miss the Xeelee by a comfortable margin. But at the last minute, a big deflection from the GUTdrives – wham. We hit that bandit with sixty billion tonnes of rock and ice, moving at interplanetary speeds, out of the blue.’

  Poole was astonished. ‘Lethe, Harry – well, it was worth a try . . .’

  But when the images cleared, and more data was captured, it soon became clear that the Xeelee had sailed out of the impact site with no evidence whatsoever of physical damage, no evidence that the assault had deflected its course by so much as a fraction of a degree. The sacrifice of a moon had done the Xeelee no more harm than had Poole when he had similarly sacrificed the Hermit Crab, and, nearly, his own life.

  Father and son sat together for a while, considering the aftermath. Michael Poole, for one, wondered if he’d ever see his father in person again.

  Then he went to Earth.

  Poole stayed with his mother. Physically he was resident with her at the Poole family complex at Princess Elizabeth Land in Antarctica. He spent the next two months working on his own secretive project. The study itself was absorbing. Poole had always been able to lose himself in work. At times he lost track of the time, even the date.

  Then the Xeelee came.

  58

  It was November, in this year ad 3650. And there was fire in the sky of Earth.

  You saw it at night, flickering and sparking. Some of the great detonations could even be glimpsed in the daylight. In the thirty-seventh century, Poole supposed, there were few who feared visions in the sky. Evidence of artifice in heaven was commonplace: sunlight glinting from the solar panels of an orbital factory, or the contrail of a great profac ship mining nitrogen from the air. Sights of a kind that had been seen for a millennium and a half.

  But now the lights in the sky were a signal of something that was anything but routine, or benign. Up there, the resources of Earth, a world that was the centre of an interplanetary civilisation, were being hurled at an intruder with nothing but lethal intent. Resources and lives, Poole knew: human lives that might have spanned millennia, spent like coins.

  And through it all – drenched in a bath of energy from its assailants’ weapons, powered by wings of fractured spacetime – the Xeelee sailed on. Relentless. Unwavering.

  Now it approached Harry’s second stop line, a day out from Earth. If it broke through that crowd of ships and weaponry, nothing stood in its way
, save for Marsden’s experimental weapons at the third and final stop line.

  That, and Poole’s own, desperate last resort.

  In the final days, in his time off, though he stayed physically in the Princess Elizabeth Land compound, Poole travelled the world with his mother in spirit. It seemed appropriate. Last chance to see, perhaps.

  And now, on the very last day before the Xeelee was due to arrive at Earth, Poole stood with Muriel on a high balcony of the Waukegan Tower, in Illinois, United Americas. Virtual angels together, they were a kilometre and a half high atop a sculpted pillar of glass, steel and carbon composites, and the unreal air in their Virtual lungs was authentically thin, even chill.

  To the east stretched the placid waters of Lake Michigan, to the west a green, flat country with scattered lakes. But, unlike much of the continent, this land had not been given back to the wild. At the Tower’s foot the remains of old Waukegan had been largely preserved, ancient buildings of concrete and stone. Further out were the rectangular layouts of farms: an open-air museum, Poole knew, a monument to the days when humans had had to coax all their food from the stubborn ground of Earth.

  The sky was bright, sunlit, though marred by silent detonations overhead.

  They were alone up here. In fact, Poole knew, the Tower was mostly abandoned. People were seeking refuge wherever they could, wherever seemed safe. Many had gone underground, to basements, ancient cellars, even a few Anthropocene-era museum-piece nuclear war bunkers. Some had taken in weapons, to keep out anybody who tried to follow them into whatever refuge they had found. Others had congregated around government centres, pleading or protesting, stretching the resources of the Federal Police.

  The mostly empty Tower, though, seemed peaceful.

  ‘I’m still not sure why you brought me here, Mother. Today of all days.’

  ‘I’ve been thinking of witnessing,’ she said thoughtfully. ‘You know that some groups have been formalising this, ever since the Xeelee threat to Earth became apparent. Jack Grantt’s doing the same thing at Mars, of course. Whether or not we can stop this blight on the Earth, at least we can watch, remember.’

  Poole grunted. ‘What for? So we can hold the Xeelee to account some day?’

  She smiled. ‘Well, it’s not impossible. We discussed this, Michael. Whatever we Pooles believed we knew of the future, surely all that is gone now. Lost. The future is as open as most people always thought it was. Who knows what’s to come, what we’ll achieve?

  ‘And so, here I am. Taking a last chance to see the world the way it should be.

  ‘In the end we did a good job, didn’t we? Of saving this world which we accidentally inherited – saving it from ourselves. And then we built it all up again, the way it was before us. So, in North America alone, you have Yellowstone, a rich biosphere lodged in the throat of a supervolcano, and further north the redwood forests and the taiga and the subpolar scrublands . . .

  ‘But I think it’s the very old places I like the most – old in human terms, I mean. Deep in central Asia you’ll find the Altai mountains, one of the last refuges for Ice Age fauna: moose, reindeer, musk ox, lynx, wolverines. I must show you if there’s time. Go there, Michael, and you have a deep sense of belonging. Because these were the environments in which we evolved. And which our more recent ancestors restored and preserved, as one would shelter an ageing parent.’

  ‘Yet you come here, on the last day. To this museum of farmland?’

  ‘But this is an ecology too, Michael. If an artificial, heavily engineered one. Engineered by us. And perhaps there’s a lesson in that. There are some ethicists, you know, who question whether this is a crime at all. The Xeelee’s crusade against us.’

  Poole grunted. ‘I don’t follow. How can it not be?’

  ‘Here we are on top of a Tower. Look at it from an elevated point of view, Michael. We ourselves have managed ecologies for millennia – like this one – and we know that death is as essential a process in keeping an ecology healthy as is life. Even the primitive conservationists of the Anthropocene understood the importance of predators, especially top predators. In the Yellowstone forests, wolves prey on elk populations, which would otherwise breed out of control, eat all the tree saplings, and produce a wilderness. In the waters too—’

  Poole scowled. ‘Are you suggesting the whole Galaxy is some kind of ecology, Mother? And that the Xeelee is nothing but a pike in a pond full of little fish?’

  She glanced out at the expansive fields of swaying grasses. ‘Sometimes I find it comforting to think that way. That for all our intelligence, all our technological ingenuity, we’re really nothing more than components in a great natural cycle. Even the Xeelee.’

  ‘But you don’t believe it.’

  She grinned, fiercely. ‘Not for a second. And even if it were true, maybe today is the day of the herbivores.’

  He felt a subtle vibration at his wrist: a monitor, bearing news. He glanced at it. ‘Ah. The Xeelee broke through the three-million-kilometres stop line. The defenders fought hard . . .’

  She absorbed that bit of information. ‘We always thought it would come through. So, one more day and it will be at lunar orbit. And after that . . . Michael, I’ve got every faith in you. And so has your father.’

  ‘Harry?’

  ‘Believe it.’ She smiled. ‘Anyhow, at this point he doesn’t have much choice.’ She stepped back. ‘Go to work. Come what may I’ll wait for you at Princess Elizabeth Land.’ And she winked out of existence.

  59

  Well before that final day, as the Xeelee had sailed towards the last stop line at lunar orbit, Nicola Emry and her Monopole Bandits had gathered on the Moon itself, training incessantly, preparing the technology of war.

  And in these last hours, in his own flitter, Poole impulsively made a hurried flight to meet her there, in person, at the Copernicus Dome. He’d tried a Virtual projection, but the exclusion protocols were even tougher than for a physical visit.

  Even so it wasn’t an easy journey. Cislunar space was crowded. As the Xeelee loomed, and people instinctively sought refuge, there were massive migrant flows travelling from Earth to Moon – and even, remarkably, some coming back the other way.

  But as Poole came in for a final landing close to the venerable Copernicus Dome, on a landing apron scarred by centuries of rocket blasts, he saw a small, brave fleet gathered: modified flitters, small, fast, highly manoeuvrable craft. These were the ships dedicated to Nicola’s special mission, equipped with Marsden’s monopole weapons. Just six of them, six ships. From Poole’s vantage as he approached, they were fragile specks against the grey face of the Moon.

  But each bore, incised on its flank, the Poole Industries corporate logo, and a green tetrahedral frame.

  He found Nicola in a mess room, with a handful of her colleagues from Gallia.

  The Copernicus Dome was an old facility, built into the shell of a big, long-abandoned Anthropocene-era Moon base. The lighting seemed poor, the fittings shabby, and even in this mess room there was always a smell of burning, as if the dome still leaked Moon dust which oxidised enthusiastically in the air.

  The fliers stared at Poole as he approached, and fell silent.

  They all had tattoos right at the centre of their foreheads, angular and green. So did Nicola, in fact, a new acquisition. Ugly, crude markings, disconcerting in their very placement. Casual in their mess suits, showing no signs of nerves, the crew looked like they fitted in here. In fact Poole suspected they all were genuinely young, like Nicola not AS-preserved but with the fast reflexes and reckless courage of true youth. Poole was twenty-nine years old now. They made him feel antique.

  Nicola introduced him briskly, parroted names that he knew he would never remember, and then led him over to a table in a corner of the hall. She snapped out commands for water and bread to hovering bots. ‘Had to get you away from my Bandits. Didn’t want
hero worship closing down their thinking, not now.’

  ‘Hero worship?’

  ‘Come on, Poole. You must be aware of the propaganda the Stewards have been putting out about you and your daring feats. Especially your dad, who is not averse to glory by association. To them, you’re Michael Poole the hero pilot—’

  ‘Poole the idiot.’

  ‘Who rammed a Xeelee Probe, trying to save the Earth. What’s not to worship?’

  He reached out, tentatively, and pushed back her short hair so he could see her forehead better. The tattooed tetrahedron was green, just like on the hide of the Wormhole Ghost. Just like the amulet which his mother still studied.

  ‘That’s your fault too,’ Nicola said.

  ‘The Sigil of Free Humanity?’

  ‘It’s become a kind of fashion. Look, I don’t care what they believe about you, as long as it motivates them to fly their ships that little better.’

  ‘And what motivates you, Nicola?’

  ‘You know what. I need to fight, for once in my sorry life. As opposed to rebelling against my mother, which is what I’ve mostly been doing up to now. Fight this thing that’s threatening my home planet . . . Pretty good reason for getting out of bed, right? How’s Plan B coming along, by the way?’

  ‘Never to be used, I hope.’

  She shrugged. ‘Well, it’s evidently kept you busy. I suppose I appreciate you coming out to – what? To say goodbye, before I get my head shot off?’

  That was exactly why he had come, of course. But, sitting here, he suddenly felt that wasn’t enough. On impulse he asked, ‘Will you take a passenger?’