Space Sounds: The Music of the Cosmos

"In space, no one can hear you scream". The chillingly accurate tagline of Ridley Scott's 1979 space horror classic, Alien, is often belied in science fiction movies, forgetting that in space there is no air, and hence no sound. Space today is terrifyingly silent. But it wasn't always thus: the early universe was filled with hot plasma in which sound waves could travel. The cosmos was quivering with the aftershocks of the Big Bang. It is one of the greatest achievements of modern physics that...