House of Suns by Alastair Reynolds Page B

from across the galaxy, from the entirety of the meta-civilisation. On the face of it, this process looks omnivorous - you don’t appear to favour one line of investigation over another.’
    ‘Such an impression would be understandable.’
    ‘But on deeper inspection, we’ve found hints of structured enquiry. Those travellers who have made it in and out of the Vigilance, both intact and insane, have found certain data sets prized over others. You value certain forms of information more than others, at least when your transactions are examined over deep time, across countless examples.’
    ‘And the nature of this bias?’
    ‘Andromeda,’ I said. ‘Specifically, the Absence. Taking the long view, the Vigilance can be seen as having a single, all-consuming purpose - even though that purpose is sometimes obscure. You’re organised to gather every known snippet of data concerning the disappearance of the Andromeda galaxy and anything connected with that event.’
    ‘Many civilisations are fixated on the Absence. It would be difficult for a galactic society not to be.’
    I dared to shake my head, though I had no idea if the gesture was visible. ‘Everyone thinks about the Absence, that’s true. Everyone worries about what it means. But even the Commonality hasn’t gone much further than that. A few observations, a few theories, but that’s it. Mostly, we’ve learned just to get on with life. That might seem blinkered, short-sighted, a kind of denial, even, but what else can we do? Whatever’s happened to Andromeda, it’s bigger than anything in our experience. Even if we understood what had happened, we couldn’t begin to do anything to stop it happening here. It’s symptomatic of something so far beyond our conception it might as well be an act of God.’
    ‘Perhaps that’s exactly what it is.’
    ‘God snatches a galaxy out of existence, as a warning against human hubris?’
    ‘Even if it is the work of God - a hypothesis our data does very little to support—it would be inaccurate to describe the Absence in those terms. Andromeda may not be visible any more, but there is still something there. There are even some stars left over, caught outside the Absence when it formed. In truth, it would be better to call it the Occlusion.’
    ‘The name’s stuck, I’m afraid.’ But I thought on what the curator had said and reminded myself that he was correct. The Commonality’s own observations concurred: Andromeda had not so much gone as been blacked out. Just as the Vigilance’s Dyson swarm blocked out the light of the Milky Way, so Andromeda continued to mask the glow of the rest of the universe, all the way back to the fierce simmer of the cosmic microwave background. But the thing that was sitting where Andromeda used to be was not precisely a galaxy, either. It was more like a squat, black toad, a fat blob of darkness with the razor-sharp edge of an event horizon. But it was not a black hole. As the curator had mentioned, there were stars and globular clusters still circling beyond the fringe of the blob, and their orbits were not what one would have expected if they were travelling so close to a black hole’s surface, where frame-dragging would have played a role. Those outlying bodies moved as if nothing had changed; as if Andromeda was still there.
    No one had an inkling as to what that black toad really signified. But one thing was clear, ominously so: Andromeda was a galaxy much like our own. Life could have arisen there, as it had in the Milky Way. It was even possible that life had still been going on there until the moment of the Absence. The fear was that what had happened to Andromeda might happen to us, if we were not careful.
    ‘Some of us think it’s a protective measure,’ I said. ‘It’s the And romedans building a wall around themselves, to keep us out. They’ve watched us spread through our own galaxy and they don’t like what they see.’
    ‘A wall is also a prison. Would that