Deciphering gravitational waves

When two black holes collide, the impact is so big that we can detect it all way here on Earth. These objects are so immense that their collisions send ripples through spacetime itself. Scientists call these ripples gravitational waves. Although Albert Einstein predicted the idea of gravitational waves all the way back in 1916, physicists didn’t directly detect them until 2015 at LIGO (the Laser Interferometer Gravitational-Wave Observatory).