Black holes are some of the most mysterious objects in the universe, but they aren’t always silent. When two black holes are close enough to each other, they spiral towards one another, eventually crashing in an enormous explosion and forming a single, larger black hole from the combination.
During this process they emit gravitational waves, ripples in the fabric of space and time that reach us here on Earth. These travel to us and change the distance between your nose and your ear, but by much, less than the a single atom! We are able to detect them with huge, sophisticated gravitational wave detectors – such as with the Laser Interferometer Gravitational Wave Observatory (LIGO) in the United States.
