Gravitational Waves: Einstein was right!

People around the world cheered yesterday morning (Feb. 11) when scientists announced the first direct detection of gravitational waves — ripples in the fabric of space-time whose existence was first proposed by Albert Einstein, in 1916. The waves came from two black holes circling each other, closer and closer, until they finally collided. The recently upgraded Large Interferometer Gravitational Wave Observatory (LIGO) captured the signal on Sept. 14, 2015. Not every scientific discovery gets this kind of reception, so what exactly is all the hype about, and what's next for LIGO now that it has spotted these elusive waves?