Astrophysics for People in a Hurry, by Neil deGrasse TysonRead about the other entries on the list.
Tyson is not just one of the smartest men in the world, he’s one of the most personable and charismatic. His book is, therefore, fun. He doesn’t use a lot of scientific terms, but instead explores space, time, and the known universe in simpler ways that even folks who have never had any scientific training will find incredibly easy to understand. It’s like having a conversation with your really smart, really funny uncle.
--Marshal Zeringue