The problem with "hard" science fiction is that it often tries a little too hard to get the science right at the loss of storytelling. When it's good, the science lends a believability factor to what would otherwise be a completely fantastic tale. When it's bad, it feels like a textbook with spaceships. The Martian threads this needle to a degree, thanks to its gripping Apollo 13esque survivor tale. Like Apollo 13, it is filled with NASA jargon and fairly complex science that threatens to overwhelm the gripping plot. But like our protagonist, who finds a way (with science!) to pull himself out of some hairy situations, Andy Weir is able to squeeze out of overly complex passages just when he needs to. And though I felt engaged with the plot, it was hard to manage any connection with the main character, despite most of the book taking place as his diary entries. He's certainly likeable, but it's hard to get any sense of Mark Watney other than the fact that he's an earnest, wisecracking nerd with serious MacGyver skills.