The Book of Unexplained Mysteries: On the Trail of the Secret and the Strange

Everybody loves a good mystery, and an unsolved mystery is even better. Sometimes, the questions can be more interesting than the answers. The Search in Extraterrestrial Intelligence [SETI] has recently hotted up, with a whole new wave of research going to show that we will always be fascinated by what we don't understand. Was 'The Wow Signal' a radio transmission from deep space? Or was it the resonating frequency of a passing comet?
Often, it can feel as if professional explainers of all s...