Odyssey

Nebula Award: Best Novel nominee (2008).

To boost waning interest in interstellar travel, a mission is sent into deep space to learn the truth about "moonriders," the strange lights supposedly being seen in nearby systems. But Academy pilot Valentina Kouros and the team of the starship Salvator will soon discover that their odyssey is no mere public-relations ploy, for the moonriders are not a harmless phenomenon. They are very, very dangerous – in a way that no one could possibly have imagined.