The Laser Interferometer Gravitational Wave Observatory (LIGO) is a large-scale physics experiment and observatory designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. LIGO operates two facilities in the United States: one in Hanford, Washington, and the other in Livingston, Louisiana. These observatories use laser interferometry to measure the minute distortions in spacetime caused by passing gravitational waves.
