Excellent book. Probably too meandering for some, but I love the intersections of science with human interest and history.

I adore his writing: clearly explaining fairly complex processes without getting dry (and generally with a wink and a nod*), helping visualize brain boggling numbers, giving historical context, and never talking down to the reader, all mixed with serious appreciation of irony, wry words here and there, and a certain goofy sense of humor. Oh, and he tells you what really went down at Roswell. (Really.)

*But* if you're the anxious sort, really anxiety inducing. So be warned. Opening with all the ways to die by volcano made me have to put this down for a few weeks. Chemical warfare and experimentation, down for another week. Inhuman (all too human-animals can't come up with this shit) military actions, how much radiation we're breathing in at any given moment, the likelihood that we've utterly fucked ourselves already...Yeah.

*He has wonderful funny, snide, and occasionally terrifying endnotes. This is a science writer for Pratchett Fans.**

**And sometimes his endnotes have footnotes to check his site for yet more detours.