Mars
It is a gripping page-turner of the first manned mission to Mars, and the hopes of making the most startling of discoveries - life on another planet. The book's tension comes from a great balance of the personal story of the astronauts, the hard-science of the mission, and the all-too-realistic dimension of earthly politics. Real drama cloaked in a sci-fi setting.
Looks like I'll be reading the whole series now!