House of Suns

by Alastair Reynolds

  There was no need to discuss the case of Silver Wings. Galingale was correct in all respects, and every one of us knew it. When you already have some of the fastest ships in the galaxy, defending against pursuers is seldom the highest priority. That did not mean our ships were powerless against a chasing adversary, but that the most effective weapons - the ones that were too large or cumbersome to steer - were normally optimised for forward attack.

  ‘She’ll still have an impasse raised as soon as you enter weapons range,’ Charlock said. ‘What makes you think you’ll get through it any easier than our ships did?’

  ‘I’m not saying I will. But at least I won’t be trying to hit a specific target, or avoid hitting sensitive areas. I can just concentrate my fire wherever I sense the greatest weakness in the impasse, or the underlying hull. Now we know that the stardam is her objective, stopping that ship - destroying her, if necessary - has become more important than just slowing her.’

  He was glossing over the uncertainties regarding the destination, the possibility that it might not be the stardam, but I was ready to let that slide for now.

  ‘Without an opener, they won’t achieve anything,’ I said.

  ‘And you’d stake the reputation of the Line, and the future stability of several human civilisations, on that assumption? Sorry, Campion, but we can’t trust Lady Luck any more. Lately she’s taken to pissing on us from a great height.’

  ‘I won’t sanction it,’ Betony said. ‘Not while we know Purslane’s still alive. She may come through with a transmission at any moment - we can’t guess the conditions she’s under.’

  I allowed myself a moment’s relief.

  ‘But it’ll take a while for Midnight Queen to reach attack position, won’t it?’ Betony went on.

  ‘If I put myself into abeyance and disengage all safeguards, I can be within attack range in thirty hours. Unless Silver Wings slows down, no other ship has the capability to cross that gap.’

  Betony began to turn away. ‘Do it. You have Line authority.’

  ‘What...’ I started to say.

  Betony silenced me. ‘He keeps a channel open the whole while. He doesn’t get authorisation to attack until we’ve reviewed the data again, when he’s nearly in range. That’s thirty hours, Campion. If we haven’t heard from Purslane by then, I think even you would have to admit...’ But that was as much as he could bring himself to say.

  ‘I swear I won’t attack unless we know she’s beyond all hope,’ Galingale said. ‘Now excuse me, if you will. I need to make some arrangements.’

  His imago buzzed with static and vanished from the garden.

  CHAPTER THIRTY-FOUR

  Synchromesh did things to my body. It slowed other processes besides the perception of time. But after more than two hours of keeping that weapon on Cadence - more than twenty hours of actual time—I began to sense a growing heaviness in my abdomen, a warning rumble that there were biological processes that were no longer happy about being held in check. My thoughts took on a frayed, burred quality, like old rope. I began to slip in and out of alertness - more than once daydreaming that Hesperus was in fact up and well, and that between us we had managed to overcome the robots. Each time I snapped out of these interludes with a renewed determination to stay watchful, but the effort was taxing. Cadence was watching me with venomous interest, listening to the ebb and flow of my mental processes. To her, my mind was lit up like a stained-glass window. She was waiting for certain facets to darken, and then she would act.

  At twenty-four hours, the chronometer brought me back into realtime. I felt just as drained and foggy-headed as when I had been in thrall to Synchromesh, but now each second hit me with unbridled force.

  ‘It’s becoming difficult now,’ Cadence observed.

  I stood up, my legs two pillars of numbness slowly transmogrifying to burning pain. With effort I walked to the command console again, still holding the energy-pistol on Cadence. I might have missed it, but I did not think we had come under attack again.

  ‘Campion,’ I said, speaking at the console, ‘this is Purslane. I’m still here, wondering if you can hear me now. Anything I need to know?’

  The silence stretched like tortured spacetime. I prowled the room, eyeing the two broken robots, wondering what was keeping Campion. A side-effect of Synchromesh withdrawal is that the ordinary flow of time can occasionally seem sluggish, until the brain readjusts. But even with this knowledge I still felt as if an unreasonable amount of time had passed. I was just about to send another message when his voice came over the speaker.

  ‘You’re still alive!’ Campion said delightedly. ‘Thank God. We hadn’t heard anything for so long, we were starting to fear the worst. We knew you couldn’t get a signal through when the impasse was raised, but after the attack was over we couldn’t understand why you were still silent. I started worrying, all right? You know about the attack, I’m assuming. We managed to hit Silver Wings, but not as well as we’d hoped. The good news is we only lost ships, not shatterlings. Charlock, Orache and Agrimony are still with us, aboard our vehicles. The main thing is, we haven’t given up. We also think we may know where you’re headed. Talk to me, Purslane. Tell me what’s happening.’

  ‘Before you say anything else, tell me the destination,’ I said.

  His reply came back a little more than four minutes later. They had closed the gap, although only by a small margin.

  ‘Nothing’s definite,’ Campion said, ‘but we’ve extrapolated your course and found something. We don’t know the significance of it yet - there’s a mountain of uncertainty to deal with. But on the face of it, if we take our best estimate of your trajectory and run it out to sixty-two kilo-lights, there’s something there. It’s not just another solar system or the boundary of a mid-level empire. There’s a stardam, Purslane - and it’s one of ours.’

  I glanced at Cadence, making sure she was not getting up to any mischief. ‘A Gentian stardam. You’re certain about that.’

  ‘Beyond any doubt. It’s been there for three million years - half the age of the Line. At least, it looks like one of ours - we’re the ones who are supposed to be monitoring it, making sure it keeps doing its job.’

  I thought of the stardam Campion had stabilised near the Centaurs’ solar system. ‘What do you mean, it looks like one of ours? Either it is or it isn’t. There should be a clear record in the trove of when we installed it, who was involved, the client civilisation or civilisations, what kind of sun needed trapping, why it wasn’t a job for the Rebirthers or Movers.’

  ‘It’s definitely Gentian,’ Campion came back, ‘but the trove record is much sparser than we’d normally expect. And it’s difficult to corroborate, too. According to the trove, the shatterling in charge of the initial installation was Orpine - he was the one who gathered the ringworlds and placed them around the star. But Orpine’s dead - he went more than a dozen circuits ago.’

  In other words, I thought to myself, attrition had taken Orpine not very long after he would have installed the stardam. Searching my mind, I tried to recall the circumstances of his disappearance, but without access to my trove I was powerless. Attrition had taken more than a hundred shatterlings even before the ambush, and with the best will in the world I could not recall the precise details of how each had died. In some cases it would never be known.

  ‘Orpine vanished,’ Campion went on. ‘We don’t know what happened to him. Since then, the stardam’s taken care of itself - we’ve monitored it, of course, and once every circuit or so, one of us has been tasked with making an inspection fly-by. Other than that, there’s really not much to say. The star in question was an O-type supergiant, brushing within a dozen lights of two emergent cultures, neither of which had regained interstellar capability at the time the dam was installed. If the star had blown, it would have disassociated the ozone in the atmospheres of their homeworlds, leading to massive genetic damage in the human populations. They’d have all died out within a year. Scaper intervention
might have helped... but contact was considered risky, and this was at a time when Gentian Line was anxious to assert itself within the Commonality.’

  ‘And these civilisations? What about them now?’

  ‘Both gone,’ Campion said four minutes later, after I had examined Hesperus for further signs of life. ‘One blossomed into a reasonably well-developed empire, encompassing about five thousand systems. Then they got into a micro-war with an outgrowth of the Vermillion Commonwealth and that was their fifteen minutes over and done with. The other culture never got beyond chemical rockets and fusion bombs before deciding they’d spare the galaxy their continued existence. Now ...’ He paused, as if he was reading from the trove again. ‘Beyond that, things aren’t so clear-cut. If the supernova happened today, it would inconvenience a number of bordering civilisations. There’d be deaths, certainly - maybe in the tens of billions. But these are technological societies that’d have the means to organise evacuation and biosphere-shielding efforts. There’s no one so close that we’d be talking about system-wide extinctions.’

  ‘We’re not thinking about a supernova happening now,’ I said. ‘We’re thinking about the premature collapse of a stardam. A Type Two supernova gives up its energy over the course of months, tailing off over years. When a stardam fails, you get all that energy in one flash.’

  ‘I know; it could be a lot worse. We know what happened to the Consentiency of the Thousand Worlds - that’s the one and only time a stardam’s ever failed on us. But that dam was smack in the middle of their empire, and they weren’t remotely ready for it.’

  There was no need to remind me about Ugarit-Panth.

  ‘Could something like that happen now? The death of an entire civilisation?’

  ‘I don’t know. No one looks as vulnerable as the Consentiency did back then. And there’s still the possibility of warning them ahead of time. Even if Silver Wings reaches her maximum speed, she’ll still be slower than light by one part in ten thousand. That’s not much of a difference, but if we sent a light-speed signal ahead of us now, it would still reach the locals six years before you do. Granted, that isn’t sufficient time to evacuate dozens of solar systems. But it would be enough time to put contingency measures in place - time to dig bunkers, move populations underground or into armoured ships. And you’re not moving that quickly, anyway. You’re holding at point-nine-nine-nine - giving the locals sixty years, not six. That really would be enough time for them to start moving people from system to system.’

  ‘It worked, then. Hesperus really did manage to get some of the other engines up and running.’ I glanced at him again, but nothing had changed.

  ‘He is not coming back,’ Cadence said.

  ‘What we don’t know is the point of this mission, even if the stardam is the target,’ Campion said. ‘If the robots mean to initiate a war, then detonating a stardam in the middle of a galaxy might be seen as a psychologically valuable opening move. But it won’t inflict real damage. They’ll sterilise space for a few thousand light-years, maybe even trigger a few secondary detonations. At worst, even if we don’t warn them ahead of time, it’ll touch no more than six or seven civilisations, none of which are major players. It won’t damage the Commonality in any meaningful way. The other big-league factions, the Rebirthers, the Scapers, the Movers ... they won’t be affected either. If they’re hoping to knock the hub out of the meta-civilisation, this is the wrong way to do it.’

  Perhaps all they wanted to do was punish us, I thought - to hurt us the way we had hurt that earlier machine civilisation. Not to wipe us out completely, but to let us know that the crime had not been forgotten, and most definitely not forgiven.

  That did not strike me as a very robot way of thinking, though.

  ‘But there’s a deeper objection, above and beyond the military pointlessness,’ Campion said. ‘They can’t break it open. Stardams need maintenance, and sometimes they fail. But there’s nothing they can do to make one fail ahead of time if it hasn’t already started to go wrong.’

  ‘What if they were to use Silver Wings as a relativistic battering ram, driving her into the stardam at full speed? Could that achieve anything?’

  ‘No one knows for sure - it’s not exactly something you go around doing just for the hell of it. But there have been cases of ships ramming stardams, or Prior ringworlds, at near-light speeds. In all documented instances, the structure remained intact. Ringworlds shatter if they’re not handled properly, but they’re massively resilient against impacts. Perhaps the robots have data we don’t, enough to convince them that they can smash the dam with Silver Wings. It would at least explain why they needed a fast ship—’

  ‘If they slow down, and tamper with the dam?’ I asked.

  ‘If we can get a warning signal ahead of you, the relevant civilisations can place an armada around that dam, above and beyond the defensive systems already in place. Silver Wings would make a difficult target at cruise speed, but if she was forced to slow to system speeds, I wouldn’t rate her chances very highly.’

  ‘Me neither,’ I said, more to myself than Campion. I had still not told him about the earlier wave of Machine People and the awful, inexcusable thing we had done to them. The knowledge sat inside me like a dark stone, trying to force its way to the surface. I did not want Cadence or Cascade to know how much Hesperus had told me, because some of his knowledge could only have come from his time as the Spirit of the Air. ‘But if they had an opener,’ I said, almost before I could examine the words and decide if it was wise to say them aloud, ‘a one-time opener, like the one the Line gave you when you were sent to the Centaurs... that would work, wouldn’t it?’

  ‘I only used the opener to adjust the stardam.’

  ‘But there are openers that do more than that. You only had Line authorisation to make adjustments - it was too soon to take the stardam apart; the energy levels were still much too high. But if they’d sent you to dismantle a stardam that had already served its purpose, so that those ringworlds could be used elsewhere—’

  ‘They’d have given me a single-use opener with full dismantlement privileges,’ Campion said, finishing my sentence for me four minutes later. ‘But they don’t give out those unless there’s a cast-iron reason, with full Line oversight. The key’s tuned to a specific stardam - it can’t be made to open another one prematurely.’

  ‘But somewhere there must be a key for this stardam. If not a key, then at least the information to make it.’

  Campion corrected me. ‘There’s only ever one key that lets you take a stardam apart. It’s made at the same time as the dam, code-locked at the deepest levels. Nothing else will work, and no one keeps a record of those codes. The thinking is, better to lose the key and never be able to open the dam than risk a duplicate copy falling into the wrong hands. It means some of our ringworlds are tied up shielding stars that have already turned cinder, but that’s a price worth paying.’

  ‘And the one for this stardam?’

  ‘Destroyed in a micro-war, only a few hundred thousand years after the dam was installed. According to the trove, anyway. But at this point I’m not sure I’d take anything in the troves as gospel. We thought we were being clever, lying to Ugarit-Panth. But we’ve been feeding ourselves another set of lies all along.’

  I looked at Cadence again. All of a sudden, with the revelatory force of daylight breaking over a dark landscape, it was clear to me why they wanted my ship.

  Silver Wings of Morning was completely incidental to their plans. It helped that she was fast, but there were other fast ships in Gentian Line and mere speed was not the central issue. They had not come all the way to our reunion on the off-chance of getting a ride to the stardam. If all they needed was to reach that point in space, they could have saved time and effort just by going there directly. They had not even taken control of Sainfoin’s ship when they were her guests.

  They had come for me. Not because of my ship, or because of something in my head, but because there was s
omething in my ship they needed. Long before the terms of my censure had been decided upon, the robots had been steering the Line towards a single objective.

  Because somewhere inside Silver Wings of Morning was the single-use opener, keyed to the stardam.

  I felt dizzy, as if I had ascended into thin air too quickly. It was not a question of needing corroboration. Now that the idea had fixed itself into my skull, I knew that I was right. On some level, I had known all along. Ancient memories could be scrubbed, but they could never be wiped completely.

  I had always been a hoarder, unwilling to throw anything away.

  There had been a reason for that.

  ‘Purslane,’ Campion said, when the dizziness had begun to ease, if not pass completely, ‘there’s something you ought to know, in case we lose contact again. Galingale’s going to have another try at crippling Silver Wings. There’s no harm in the robots knowing our intentions - they’ ll have guessed them by now if they’ve seen Midnight Queen coming closer. If there’s anything you can do to protect yourself, you should do it.’

  ‘I will,’ I said. ‘But there’s something you need to know as well. Nothing matters more than stopping this ship. We may not know why the robots want to break open that stardam, but we can be sure it’s not going to be in our best interests. Now that we know the destination - I’ m certain about that, by the way - Silver Wings must not be allowed to get there. I’m not talking about crippling her, Campion. You can’t risk failure now, not when so much is at stake. Tell Galingale to use everything he has. Tell him to shoot me down.’

  PART EIGHT

  Relictus may have disappointed Calidris, but he did not disappoint me. Our losses continued without respite, but in his dungeon the failed apprentice at last pieced together the elements of the counter-spell. Because of his restraints, he could test only the simplest parts of it in isolation. He pored over the details for many weeks, refusing to allow even the minutest detail to go unexamined.