Belt Three

by John Ayliff

  ‘It won’t let me in,’ she said. She poked the pad again, her finger passing through it, and a red symbol of denial flashing up.

  ‘Aurelian, give us access to the logs, please,’ Jonas said.

  ‘Only the captain has authorization to access Doctor Rasmussen’s logs,’ the computer said.

  ‘I’m aware of that,’ he said. ‘On my authority, please grant Keldra permission to access all the logs.’

  There was a slightly too long pause, and then the computer said, ‘Very well, Captain.’

  Captain Marszalek stepped out of the transit module into the lab. Doctor Rasmussen stood in front of the partition, with her back to the captain, and didn’t turn around; Marszalek couldn’t tell whether she hadn’t heard her enter or was just engrossed in her work.

  On the other side of the partition, a cylinder of ice ran the length of the temperature-controlled lab, cradled in the network of supports. Its surface was the texture of stone but a sparkling white colour, marbled with veins of grey and brown. This was the heart of Rasmussen’s project; the ice core the Aurelian’s EVA team had drilled from a comet three days ago, just before they’d heard news of the Jupiter Incident.

  Rasmussen looked decades younger than when Marszalek had first met her. Studying this comet was the culmination of her life’s work, and it had reinvigorated her; now she stood tall, radiating energy. She stood amid a cloud of data, but she had her eyes closed, her hands twitching every couple of seconds. Beyond the partition, one of the robots was moving very precisely up to the cylinder, raising an arm tipped with a cutting laser.

  Marszalek cleared her throat. ‘Doctor Rasmussen?’

  The robot stopped. Rasmussen looked round at Marszalek with a distracted frown. ‘Give me a moment.’ She turned back to the ice cylinder and the robot started moving again, angling the laser-arm into position.

  Marszalek went to peer through the glass. ‘You’re still studying the comet?’

  ‘Of course, I’m still studying the comet,’ Rasmussen snapped. ‘Just because the Dodecs have appeared doesn’t mean we should drop everything else. Everyone is too obsessed with them.’

  ‘They destroyed Jupiter,’ Marszalek said flatly.

  The robot wobbled for a moment while Rasmussen waved a hand dismissively. ‘Every university on Earth and Mars is poring over the data from the Jupiter Incident. They don’t need me to chip in from out here. I’ve got this core sample right in front of me and I’m going to study it.’

  Marszalek paused, considering the best way to deal with the scientist. Showing an interest might soften her up. ‘You said you thought you’d found life,’ she prompted.

  ‘I have found life,’ Rasmussen said, not looking back at Marszalek. The robot’s projector arm was in position. A crimson laser beam shot out and traced a quick circle. Another arm, this one tipped with a claw, carefully pulled the sample cylinder out of the ice. ‘I’m seeing how deep the life goes, whether it’s spread through the whole comet or just isolated pockets. It’s not what I’d…ah…what I’d expected.’

  The robot pulled the ice core free, supporting it with its three claws, and trundled towards a sample container at the side of the room. Rasmussen relaxed, releasing control of the robot and allowing it to continue autonomously.

  ‘What do you mean, it’s not what you expected?’ Marszalek asked.

  Rasmussen shot her a look, as if to say, you’re not a scientist, you wouldn’t understand.

  ‘Give me the layperson’s version,’ Marszalek said. ‘I’m interested.’

  Rasmussen didn’t look as if she believed her, but she began talking anyway.

  ‘The microorganisms are too complex. I can’t detect the more primitive stages they must have evolved from. In fact, there are vestigial systems; signs that they might have developed from a more complex form of life, adapted to become simpler. Their chemistry isn’t well suited to the comet, either, not what you’d expect for a life form that evolved here. They’re adapted to survive in this place, but I don’t think this is where they originated.’

  ‘Where, then? A planet?’

  ‘More likely a comet with more hospitable chemistry. Their original home might have been destroyed, but some microbes survived in fragments and found their way to this one.’

  ‘It looks like life will find a way to survive anywhere,’ Marszalek said.

  Rasmussen gave her a patronising look. ‘What did you want to talk to me about, Captain?’

  ‘I wanted to let you know that we’ve been reassigned,’ she said. ‘We’ll begin full burn acceleration in an hour.’

  Rasmussen pulled herself up to her full height, glaring piercingly at her. ‘That level of acceleration risks disturbing my experiments.’

  ‘I know. That’s why I negotiated with the Authority for the one hour delay. You have a chance to make the comet secure.’

  ‘I was told that this ship would be at my disposal.’ Rasmussen’s voice was as icy as the comet.

  Marszalek was shocked to see such energetic anger from such a frail-looking figure. ‘The Earth Authority has declared a state of emergency over the Dodecs,’ she said. ‘You know that.’

  ‘So we’re studying the Dodecs after all? I should just drop my life’s work—’

  ‘Not studying,’ Marszalek said. ‘Intercepting.’ She was snapping as well now, not bothering to stop herself. ‘The Authority telescopes re-examined the Dodecs’ movements after the Jupiter Incident. There are groups of them converging on each of the planets. We’re to join the defence of Mars.’

  Rasmussen pursed her lips, but said nothing. It looked as though the energy was draining out of her. She waved the robot dormant and then walked out of the lab.

  The ghosts vanished. ‘That doesn’t tell us much,’ Jonas said.

  ‘They were studying a comet,’ Keldra said with quiet resentment. ‘She talked about universities. There hasn’t been a research university for a hundred years.’

  He wanted to care about that, but found he didn’t. ‘We’re here to learn about the Sphere,’ he said impatiently. ‘Can you find a log about the Worldbreakers?’

  The Dodec Sphere now occupied the middle of the partitioned off section of the lab, sitting amid a modified set of supports. A few sad remnants of ice on the floor were the only signs of the comet core; with nowhere else suitable to store it, they’d had to leave it drifting in space. Doctor Rasmussen stood facing the Sphere through the partition, now with a slumped posture, as if her years had finally caught up with her. The Battle for Mars had taken its toll on all of them.

  Captain Marszalek walked up beside Rasmussen. ‘Well, doctor? You said you’d worked out what they are.’

  Tensions had been fraying ever since Mars. Sometimes it seemed as though Marszalek’s main job was stopping the crew from killing one another. Or themselves: there had already been a few suicides. Rasmussen appeared to have taken one of the healthier, or at least more useful, routes to dealing with the reality. She had lost herself in the intellectual exercise of understanding the Dodecs, distracting herself, so that her emotions never got a grip of the big picture.

  Rasmussen cleared her throat as if beginning a prepared speech, and carefully conjured a model of a Dodec in the air beside her. ‘Firstly, let me tell you what they’re not,’ she said. ‘They’re not crewed spaceships.’ She waved the model’s outer layer transparent. ‘We haven’t identified everything, but it’s clear that there’s no life support mechanism. These voids,’ she highlighted the wedge-shaped spaces that made up half the Dodec’s volume between the skin and the central core, ‘were never pressurized. They’re storage, not habitats.’

  ‘They’re AIs, then,’ Captain Marszalek said.

  ‘That’s a theory that’s been going around on Earth, but I don’t think so, not exactly. They’re artificial all right, but intelligence is too strong a word.’ She chuckled at her own witticism, then continued, ‘of course, it’s hard to tell. We don’t know what computing capability might have been hidden
in the parts you didn’t give us time to examine.’

  ‘We’re on a tight schedule, doctor,’ she said sternly. ‘You know what’s at stake here.’

  Rasmussen frowned, her face creasing into well-worn lines that indicated a lifetime of frowning. Marszalek wasn’t sure that she did know what was at stake, or that she wanted to know. Some people could only cope with a major catastrophe by not thinking about it. ‘In any case,’ the doctor continued, ‘the Dodecs’ behaviour displays only rudimentary intelligence. They’re clearly the product of intelligence, but they’re not themselves very bright. They seem to be following a script, and not responding to outside events. During the Mars Incident – the Battle for Mars, I mean – they paid no attention to our fleet, even after we learned how to crack their armour. About a hundred of them were destroyed by planetary debris that they could have changed course to avoid.’

  ‘You said you’d worked out what they are,’ Marszalek prompted impatiently.

  ‘Yes, I believe so.’

  Rasmussen took a few steps into an open area of the lab, and conjured a three-dimensional chart of the solar system. The room lights dimmed. It looked uncomfortably like a school lecture. Marszalek wished Rasmussen would dispense with the theatrics, but complaining would probably just slow her down more.

  ‘The Dodecs are Von Neumann probes,’ Rasmussen said. ‘Planetary scale, self-replicating spacecraft. They arrive in a system, demolish its planets, and use the material to build more copies of themselves.’ The ghostly orrery moved, displaying the events as Rasmussen described them: the Dodec cluster arriving at the edge of the system, splitting into the hundreds of thousands of individual Dodecs, spreading to Jupiter and then to Mars, each planet exploding into a cloud of tiny shards. ‘They need two things: raw material and energy. The Dodecs that destroyed Mars and Jupiter are matching courses with the fragments of those planets. A few have already intercepted them, and the fragments have vanished, while the Dodecs gained mass. That’s what the cavities inside the Dodec are for: they store the compacted material. Meanwhile, the largest of the original clusters headed straight for the sun. Close solar orbit is where you go if you want energy.’

  ‘That’s a lot of speculation,’ Marszalek said.

  ‘There’s more evidence.’ Rasmussen zoomed the view out, making the solar system vanish to a dot and stars appear around them. ‘The theory of the Dodecs as planetary scale replicators resolves a long-standing problem in astrophysics. Current models of planet formation predict that more exoplanets should exist than we can actually detect. About 20 per cent fewer stars have planets than should, according to the models. Furthermore, the proportion of stars with exoplanets changes depending on the part of the sky you look at. Various amendments to the models have been proposed, none of them very satisfactory. But if the Dodecs are sweeping across the galaxy, destroying planets…’

  Marszalek’s eyes widened as the implications of this sunk in. ‘They’ve destroyed one-fifth of the planets in the galaxy?’

  ‘In the radius in which we can detect exoplanets, at least,’ Rasmussen said. ‘And look at Gliese 876. The first wave of exoplanet discoveries in the 2000s detected four planets around that star, but a more powerful survey in 2160 found only asteroid belts. It was put down to a mistake in the original records, but now we know about the Dodecs—’

  ‘You think the Dodecs travelled to Sol from Gliese 876?’

  Rasmussen made a tutting sound in her throat. ‘No. There must be thousands of groups of Dodecs across the galaxy, and they’re multiplying all the time. They take tens of thousands of years to travel between systems. Our Dodec cluster would have been in transit when Gliese 876’s planets were destroyed.’

  ‘Why would anyone create these things?’

  Rasmussen shrugged. ‘They’re alien. We can’t guess aliens’ motivations. They could be xenophobic and want to destroy all life but themselves. They could have something against planets. They might not even have intended it. The first Dodecs could have been built for some other purpose – selectively culling unsuitable planets, perhaps – and then one batch malfunctioned. The malfunction gets passed on to its copies. It spreads like a cancer, pushing out the healthy originals. Perhaps the Dodecs destroyed the race that created them.’

  ‘Poetic justice,’ Marszalek said.

  ‘Perhaps,’ Rasmussen said, ‘God only knows how many other civilizations they’ve destroyed. They caught us at an interesting time, though. Our situation might be unique.’

  ‘What do you mean?’

  ‘I mean, we can oppose them, but we can’t win,’ Rasmussen said. ‘The Dodecs are actually pretty simple, not to mention stupid and inefficient. Their technology is more advanced than ours – their reactionless drives and their beam projectors work by some kind of gravity manipulation technology – but they’re not more advanced by orders of magnitude. We could build Von Neumann probes that do basically the same thing using different techniques, if we were prepared for the initial investment.’

  ‘And if we had a reason to.’

  ‘My point is, they’re not that much more advanced than us. At Mars, 28 Earth Authority cruisers destroyed 417 Dodecs, and the Dodecs didn’t even fight back. They only won because of overwhelming numbers. If we’d even had current technology but a larger space fleet, we might have beaten them. A few hundred years ago, we wouldn’t have known what hit us. Astronomers would have seen Jupiter and Mars vanish, but that’s all the advance warning we’d have got. A few hundred years later, I think we’d have been able to defeat them. In cosmological terms they caught us in a very narrow window, where we could fight them but not win.’

  Marszalek blinked. ‘What did you say?’

  Rasmussen took a step back, confused. ‘I said we could fight back but not win.’

  ‘We don’t know we can win.’

  Rasmussen shrank back from Marszalek’s tone. ‘You saw what happened to Mars—’

  ‘Stop being defeatist,’ Marszalek said. ‘We know more about them now, and we have their weapon. The Earth Authority is relying on you to help them reverse-engineer something that we can use against them.’

  ‘I don’t know if that’s possible.’

  ‘I am ordering you to believe that it’s possible. Let me know when you have something.’ Marszalek stalked out.

  A moment after playback finished Keldra grunted in anger, making Jonas jump. She held up a clenched fist for a moment, looking around as if not knowing what to do with it, and then abruptly strode forward and punched the transparent partition separating them from the Worldbreaker Sphere. The material visibly vibrated, and her fist left a faint grimy mark. She put her hand to the partition again, palm open this time, and leaned on it, body bent forward and hair cascading down the sides of her face.

  ‘Unauthorized damage to the science lab partition,’ the Aurelian announced sternly.

  ‘It’s all right, Aurelian,’ Jonas said. ‘Keldra, what are you doing?’

  ‘It’s lying,’ she spat. She looked back at him. Her eyes were red.

  ‘What? About what?’

  ‘They targeted us,’ she said slowly, separating each word. ‘They saw us as a threat. They saw our potential. They saw what we could achieve, what we could have achieved, and they decided to destroy us.’

  ‘That’s not what Doctor Rasmussen thought,’ he said.

  ‘She was wrong,’ Keldra said. She was sounding a lot like Lance Cooper had during Jonas’s interrogation.

  ‘I know you want to believe that.’

  ‘Play the next log,’ she said.

  ‘Keldra—’

  ‘Play the next fucking log!’

  He turned back to the floating pad. ‘Aurelian, play the next log.’

  ‘Yes, Captain.’

  ‘We can’t understand the Dodecs’ behaviour at Mars, except in the light of what we’ve seen them do since,’ Rasmussen said. The scaffold surrounding the Sphere had grown; several robots patiently probed it with sensors. The air of the accessible se
ction of the lab was thick with floating data, abandoned streams of it where Rasmussen had used the volume of the lab as a chalkboard in her desperate calculations.

  Rasmussen summoned a picture-pane of blurrily magnified telescope footage. A Dodec slid closer to a still-glowing globule of iron that had days earlier been part of Mars’s molten core. The Dodec’s face opened and a beam of green light spilled out, visible as it scattered off the hellish red haze of gas and microscopic fragments slowly dispersing out of Mars’s orbit. The molten globule rippled where the beam touched it, and then the surface facing the Dodec danced like boiling water. A stream of liquid rushed across space and into the Dodec’s maw, twisting, as if caught up in a whirlwind. The bulk of the globule drifted towards the Dodec as it disintegrated.

  Rasmussen paused the playback. The streamer of iron droplets hung frozen in space.

  ‘The consensus on Earth is that the Dodec weapon creates a varying field of artificial gravity within the beam,’ Rasmussen said. ‘The overall force is attractive towards the Dodec, but the intensity and direction of the force varies enormously over a scale of metres. The stresses these variations set up break the matter apart, so that it reaches the Dodec in small fragments. Presumably, the Dodec finds these easier to process.’

  ‘That’s not how they destroyed Mars,’ Marszalek said.

  ‘No. The Dodec’s weapon appears to be close range, perhaps 200 kilometres, maximum, and the Dodecs don’t appear to be able to get that deep into a planetary gravity well, even with their reactionless drive. I’m showing you this because this appears to be the Dodecs’ main mode of operation. The time taken to actually destroy a planet – to break it up, rather – is tiny compared with the time the Dodecs will spend intercepting these individual fragments. If they continue at their current rate, it’s likely to take around 800 years before the Dodecs have assimilated all the Martian fragments. Long before then, the fragments will have spread out into a new asteroid belt.’