53. The Icarus Hunt, by Timothy Zahn.

The Icarus Hunt is a story about Jordan McKell, a starship pilot taking an extra contract to fly the Icarus to Earth as part of a crew of loose spacers picked up on Meima. Their trip is plagued by unusual troubles, and he's hard-pressed to figure out what is going on before something goes terminally wrong.

The Icarus Hunt is a book I first read in high school. I picked it up from the school library for cheap, and have re-read it multiple times since then. It's an extremely cohesive story, and in all my re-reads, I've yet to find a loose end that wasn't just me missing something within the text, and even though I know what's going to happen, I still enjoy reading through it again. Definitely a good one for sci-fi fans.