Book excerpt: Until Karl Jansky's 1933 discovery of radio noise from the Milky Way, astronomy was limited to observation by visible light. Radio astronomy opened a new window on the Universe, leading to the discovery of quasars, pulsars, the cosmic microwave background, electrical storms on Jupiter, the first extrasolar planets, and many other unexpected and unanticipated phenomena. Theory generally played little or no role – or even pointed in the wrong direction. Some discoveries came as a result of military or industrial activities, some from academic research intended for other purposes, some from simply looking with a new technique. Often it was the right person, in the right place, at the right time, doing the right thing – or sometimes the wrong thing. Star Noise tells the story of these discoveries, the men and women who made them, the circumstances which enabled them, and the surprising ways in which real-life scientific research works.