‘Chirps’ in space: new album captures the sound of black holes colliding

Scientists have turned electromagnetic and gravitational waves - which, unlike sound waves, can travel in a vacuum - into musical tracks

If two black holes collide in the vacuum of space, do they make a sound?

Sound waves can't travel in the almost perfect vacuum of space - no one can hear you scream, as the tagline from Alien goes. But electromagnetic and gravitational waves can, and a new album has turned these signals from space into musical tracks.