Ark by Stephen Baxter

In his previous novel, Flood, Baxter painted a grim, convincing picture of Earth inundated, with survivors subsisting on rafts while a select few left on a spaceship bound for a distant planet. Ark follows that last-ditch mission, as Holle Groundwater undergoes gruelling training and then takes off on a journey destined to last decades. Baxter's forte lies in presenting, in brilliant detail, the monotonous routine aboard the generation starship: the political in-fighting, madness and sexual jealousies that almost destroy the crew. Hope is constant, but the fight for survival is desperate, and when the ship arrives at Earth II, which turns out to be uninhabitable, the crew is divided between those who wish to push on to the next candidate planet and those who want to return home. Never has Baxter presented a more thrilling and moving glimpse of a possible future: Ark could well be his masterpiece.