The moon breaks apart on the first page and the rest of the book is the arithmetic of that, with roughly two years before the fragments make the surface uninhabitable.
The first two thirds are the best engineering fiction I have read. Orbital mechanics, resource budgets, the politics of who gets selected, and a plan that keeps degrading as the numbers come in.
Then it jumps five thousand years and becomes a different novel, and that final third is where most readers get off. I did not love it either, though the nerve of the structure is hard not to admire.
Read April 2015.
