content: This book is out of print and pretty hard to find, but if you ever come across a copy of it I highly reccommend you pick it up. It is a masterpiece of speculative essays. In it, Clarke accurately predicts many things... of course lots of things about space and satellite communications, and even an accurate description of the internet! Also of note are essays on what we should do if we have contact with an alien race, a debunking of UFO sightings (much needed), a debunking of the cliche "nothing is impossible" with a listing of things that are, much talk on the speed of light and relativity, and of course a lot about space. The two most interesting essays in my view are one that speculates on what the Star of Bethleham (Clarke settles on a supernova). Also, there is the short essay "God and Einstein" which is one of the most thought-provoking things I have ever read in my life. Highly reccommended.