Providing a definitive history of the formative years of radio astronomy, this book is invaluable for historians of science, scientists and engineers. The whole of worldwide radio and radar astronomy is covered, beginning with the discoveries by Jansky and Reber of cosmic noise before World War II, through the wartime detections of solar noise, the discovery of radio stars, lunar and meteor radar experiments, the detection of the hydrogen spectral line, to the discoveries of Hey, Ryle, Lovell and Pawsey in the decade following the war, revealing an entirely different sky from that of visual astronomy. Using contemporary literature, correspondence and photographs, the book tells the story of the people who shaped the intellectual, technical, and social aspects of the field now known as radio astronomy. The book features quotes from over a hundred interviews with pioneering radio astronomers, giving fascinating insights into the development of radio astronomy. Woodruff T. Sullivan III has been awarded the 2012 Leroy E. Doggett Prize for Historical Astronomy.