Probably the most remarkable experiments in history – that a pair of giant cars that listen for ripples in spacetime called gravitational waves – will awaken from a half a year nap on Monday. And it’ll be about 40% stronger than before. That experiment is known as the Laser Interferometer Gravitational Wave Observatory; it consists of two giant, L shaped detectors that together solved a 100-year-old puzzle posed by Albert Einstein. In 1915, Einstein had predicted the existence of ripples in the fabric of distance But he did not think these gravitational waves would ever be discovered – they seemed too feeble pick up among all the noises and vibration on Earth.
For one hundred it seemed like Einstein was right. Even as countless scientists worked on LIGO from 2002 into 2015, they failed to hear any waves. This is despite the predictions that collisions of two black holes ought to make gravitational waves in detectable levels. But that 13-year slump ended in Sept 2015, when upgraded advanced LIGO found its first gravitational wave signals from the merger of two black holes some 1.3 billion light-years away.
The following December, the team discovered a second collision event. By 2017, 3 researchers that helped conceive of LIGO earned a Nobel Prize in Physics. Science has not been the same since. The worldwide research team correlated with LIGO has today made 11 detections of massive collisions in deep space.