This book marks something of a milestone in my reviewing career: it’s the first time I’ve seen an excerpt from one of my reviews printed on the back cover. It comes from my review of Sheehan’s previous book, on Mercury , which I said ‘easily convinced me the Solar System’s 'least interesting' planet is still a pretty fascinating place.’ That wasn’t an easy task for the author, given Mercury’s unspectacular appearance and reputation – but Saturn is a different matter. With its iconic rings, easily visible through a small telescope, it’s the favourite planet of many amateur astronomers. For space scientists, too, it’s a prime target – given that two of its moons, Titan and Enceladus, look like the kind of places we might find alien life. So Sheehan’s challenge this time wasn’t to find enough material to fill 200 pages, but to distil a potentially huge subject down to that size. He meets this challenge just as successfully as the previous one – but not quite in the way I w