LIGO Scientific Collaboration Spokesperson Gabriela Gonzalez holds up a scarf depicting gravitational waves for photographs following a news conference at the National Press Club in Washington, Feb 11, 2016, to announce that scientists have finally detected gravitational waves. [Photo/IC]

Who detected gravitational waves?

The new discovery, accepted for publication in the journal Physical Review Letters, was made by the Laser Interferometer Gravitational-Wave Observatory Scientific Collaboration, a group of more than 1,000 scientists from universities around the United States as well as in 14 other countries. LIGO Director David Reitze announced on Thursday at a press conference that they detected gravitational waves. "We did it."

On September 14 of last year, the LIGO location in Livingston, Louisiana picked up a gravitational-wave signal, and seven milliseconds later, its fellow observatory in Hanford, Washington detected an identical signal. This signal exactly matched the calculated behavior of gravitational waves produced when two black holes collide.