This book started off with an interesting premise (abandoning a Mars expedition early in order to save a rival set of astronauts from another country), and continued to be interesting as the consequences of that are played out.

While this may not be the greatest SF novel of all time, it was a lot better than most, in that it is truly character driven yet has a lot of plot, much of it hard SF based. And at the end, it leaves the reader with questions to ponder--not exactly your typical SF fare. ( )