It's so cool to read about basic physics from the Man Himself. My Physics 101 teacher basically made her curriculum for Mysteries of the Sky from the book. Which is good, cause it makes scientific/scifi concepts relatively simple to understand and you kind of "get it" after you have finished reading the book. Black holes, time travel, the origins of the universe are just some of what he covers, mostly with well-placed humor to make you understand what he's explaining. I really liked this book and highly recommend it!