It's this sci-fi about a slow sort of apocalypse, allowing for people on earth to prepare survival arks in near orbit. It has a huge timeline - 5000 years, and really just massive and epic. But it got really really superboring in the middle. There are a lot of technical explanations of space stuff - orbits, the mechanics of movements of large objects in space, overall just a lot of jargon. Lots of interesting ideas. If he just spent a similar amount of time developing the characters as he did explanating orbital mechanics, it definitely would have been a much more pleasant reading experience. As it is, I plodded through the whole thing because I somehow got it in my head that sometimes you just have to grin and bear it, and I already read so much, don't quit, desiderata, etc. etc.

The final portion felt rushed. It should have been much longer. I really wanted to see how the different cultures would interact.