A worker inspects quartz fibers that suspend a mirror inside the Virgo gravitational-wave observatory. EGO/Virgo Collaboration/Perciballi
When incredibly massive objects collide violently in space, they send out ripples in space-time that reverberate through the cosmos for billions of years.
Long after the collisions happen, these gravitational waves – first theorized by Albert Einstein – pass through Earth. Over the last five years, a set of three miles-long devices in Washington, Louisiana, and Italy have been listening for these waves. The two US detectors make up the Laser Interferometer Gravitational-Wave Observatory (LIGO), and their partner in Italy is called Virgo.
Einstein predicted that noise and vibrations on Earth would prevent us from ever being able to detect gravitational waves. But these observatories proved