Svetlana originally supports Bella, but when she later discovers that they have less fuel than they thought, and that the corporation seems to have been hiding his fact, she begs for a turnaround, and turns against Bella when she refuses. This sets up the central human conflict of the story, between Bella and Svetlana, who oscillate as leaders of the expedition over time. And what about the expedition? Eventually they reach a point of no return, and they are forced to essentially colonize Janus, while trying to unlock its secrets. Janus is traveling towards a Structure around the star Spica, 260 light years distant, which means a long journey is ahead of them. And in the end this journey turns out to be unimaginably longer than they can ever have expected.

Pushing Ice gives us a dramatic, though not to my mind entirely convincing, human story of the conflict between the two women and their factions. Both have some reason for their actions, but both also do terrible things, commit tremendous betrayals. At the same time we are given a tense story of survival in an alien environment, which I found interesting but again not quite convincing. And finally we have a story about contact and communication with aliens, embroilment in inscrutable alien politics, and at the end, a story of confronting truly Deep Time, the very far future. This, to me, works best of all: the payoff here is very effective, mysterious and awe-inspiring.

I've been known to suggest that Reynolds's novels are a bit too long, and this one is as long as his others, but I must say that I was gripped throughout. There's a lot going on: a lot of neat SFnal ideas, some "small" in the sense of being fairly near future technological speculation, and others "big" in the sense of dealing with the ultimate fate of intelligent races. It's not perfect: I've already quibbled about a couple of things, and I have to say that I could not quite believe in the main characters, even though I did manage to care for them. But it is, well... cool, and it pushes my SF reader buttons just right.