Detection | LIGO Lab | Caltech On September 14, 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC), the twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA both measured ripples in the fabric of spacetime – gravitational waves – arriving at the Earth from a cataclysmic event in the distant universe. The new Advanced LIGO detectors had just been brought into operation for their first observing run when the very clear and strong signal was captured. in Fyzika > Relativita > Gravitační vlnywith 2015a.measternfyzikagravitanírelativitaseptembervlny