Albert Einstein predicted the existence of gravitational waves—ripples in spacetime—almost a century ago. But until recently there was no way to observe them. But thanks to the work of Dr. Nergis Mavalvala and her colleagues at MIT, Einstein’s theory is now a proven phenomenon. Last week, the ultrasensitive telescope her team built detected gravitational waves for the first time, created from the collision of two black holes some 1.3 billion years ago.
