A Short History of Nearly Everything
Bill Bryson, one of my favorite writers, was sitting around one day when he realized that he didn't know how they figured out how much our planet weighs. And then he began to think about all the other things that he didn't know. Being a middle-aged man, he figured it was time he found out, and he did. In this book he takes us on a grand tour through physics to chemistry to biology to geology to astronomy to ecology, and all with very little dumbing down. If you want to spend some quality time learning about the world and the universe, read this gem.