them had seen this image before; some had seen pictures that showed the same thing but with much less resolution; some had seen it with their own eyes, as a faint ochre smudge in the sky chasing the setting sun like a malformed comet. He told them that the picture was the latest and best image available to the government, according to his sources. ‘But it isn’t a comet,’ Thorn said. ‘That’s the government line, but it isn’t true. It isn’t a supernova either, or any of the other rumours they’ve put about. They’ve been able to get away with those lies because not many people down here know enough about astronomy to realise what that thing is. And those that do have been too intimidated to speak out, since they know that the government is lying for a reason.’ ‘So what is it?’ someone asked. ‘While it doesn’t have anything like the right morphology to be a comet, it isn’t something outside our solar system either. It moves against the stars, a little each night, and it’s sitting in the ecliptic along with the other planets. There’s an explanation for that, quite an obvious one, really.’ He looked them all up and down, certain that he had their attention. ‘It is a planet, or rather what used to be one. The smudge is where there used to be a gas giant, the one we call Roc. What we’re seeing is Roc’s disembowelled corpse. The planet is being pulled apart, literally dismantled.’ Thorn smiled. ‘That’s what the government doesn’t want you to know, because there’s nothing they can do about it.’ He nodded towards the back. ‘Next.’ He showed them how it had begun, over a year earlier. ‘Three medium-sized rocky worlds were dismantled first, ripped apart by self-replicating machines. Their rubble was collected, processed and boosted across the system to the gas giant. Other machines were already waiting there. They turned three of Roc’s moons into colossal factories, eating megatonnes of rubble by the second and spewing out highly organised mechanical components. They spun an arc of matter around the gas giant, a vast metallic ring, unbelievably dense and strong. You can see it here, very faintly, but you’ll have to take my word that it’s more than a dozen kilometres thick. At the same time they were threading tubes of similar material down into the atmosphere itself.’ ‘Who?’ another man asked. ‘Who is doing this, Thorn?’ ‘Not who,’ he said. ‘What. The machines aren’t of human origin. The government’s pretty certain about that. They have a theory, too. It was something Sylveste did. He set off some kind of trigger that brought them here.’ ‘Just like the Amarantin must have done?’ ‘Perhaps,’ Thorn said. ‘There’s certainly speculation along those lines. But there’s no sign that any major planets have ever been dismantled in this system before, no resonance gaps in orbits where a Jovian would have belonged. But then again, it was a million years ago. Maybe the Inhibitors tidied up after they’d done their dirty work.’ ‘Inhibitors?’ asked a bearded man whom Thorn recognised as an unemployed palaeobotanist. ‘That’s what the government calls the alien machines. I don’t know why, but it seems as good a name as any.’ ‘What will they do to us?’ asked a woman who had exceptionally bad teeth. ‘I don’t know.’ Thorn tightened his fingers around the edge of the podium. He had felt the mood of the room change within the last minute. It always happened this way, when they saw what was happening. Those who knew of the thing in the sky had viewed it with alarm from the moment the rumours began. For most of the year it had not been visible at all from Cuvier’s latitude, where most of the citizenry still lived. But no one had been of the opinion that it was likely to be a good omen. Now it had hoved into the evening sky, unignorable. The government’s experts had their own ideas about what was going on around the giant. They had correctly deduced that the activities could only be the result of intelligent forces, rather than some outlandish astronomical cataclysm, although that had, for a while, been considered. A minority considered it likely that the agency behind the destruction was human: the Con-joiners, perhaps, or a new and belligerent group of Ultras. A smaller and less credible minority thought that the Triumvir herself, Ilia Volyova, had to have something to do with it. But the majority had correctly deduced that alien intervention was the most likely explanation, and that it was in some way a response to Sylveste’s investigations. But the government’s experts had access only to the sketchiest of data. They had not glimpsed the alien machinery in close-up, as Thorn had. Volyova and Khouri had their own theories. As soon as the arc was finished, as soon as the giant had been girdled, there had been a dramatic change in the properties of the planet’s magnetosphere. An intense quadrupole field had been set up, orders of magnitude more intense than the planet’s natural field. Loops of magnetic flux curled between lines of latitude from equator to pole, ramming far out of the atmosphere. The field was clearly artificial, and it could only have been produced by current flow along conductors laid along those lines of latitude, great metallic loops wound around the planet like motor windings. That was the process Thorn and Khouri had observed with their own eyes. They had watched the loops being laid, spooled deep into the atmosphere. But they had no idea how deep they had gone. The windings must have sunk far into the metallic hydrogen ocean, deep enough to achieve some kind of torque coupling with the planet’s shrivelled yet immensely metal-rich rocky kernel. An exterior acceleration force transmitted to the windings would be transferred to the planet itself. Meanwhile, around the planet, the orbital arc generated a pole-to-pole current flow, passing through the giant and returning to the arc via the mag-netospheric plasma. The charge elements in the ring reacted against the field in which they were embedded, forcing a tiny change in angular momentum in the motor windings. Imperceptibly at first, the gas giant began to rotate faster. The process had continued for most of a year. The effect had been catastrophic: as the planet had spun faster and faster, so it had been pushed closer and closer towards the critical break-up velocity when its own gravity could no longer stop it from flying apart. Within six months, half the mass of the planet’s atmosphere had been flung into space, ejected into the half-beautiful, half- repulsive new circum-planetary nebula that was visible from Resurgam as a thumb-sized smudge in the evening sky. Now most of the atmosphere was gone. Relieved of the compressive weight of the overlying layers, the liquid-hydrogen ocean had returned to the gaseous state, liberating squalls of energy that had been pumped smoothly back into the spin-up machinery. The metallic-hydrogen ocean had undergone a similar but even more convulsive state change. That too had been part of the plan, for the great process of dismantling had not faltered once. Now all that remained was a husk of tectonically unstable core matter spinning close to its own fragmentation speed. The machines were surrounding it even as Thorn spoke, processing and refining. In the nebula, revealed as shadowy knots of coherent shape and density, other structures were taking shape, larger than worlds in their own right. Thorn said again, ‘I don’t know what’s happening. I don’t think anyone does. But I do have an idea. What they’ve done so far has been very hierarchical. The machines are awesome, but they have limitations. Matter has to come from somewhere, and they couldn’t immediately start smashing apart the gas giant. They had to make the tools to do that, and that meant smashing three smaller worlds first. They need raw material, you see. Energy doesn’t seem to be a problem — maybe they can draw it directly from the vacuum — but they obviously can’t condense it back down into matter with any precision or efficiency. So they have to work in stages, one step at a time. Now they’ve ripped apart a gas giant, liberating
