LIGO Livingston Interferometer. (Credit: Caltech/MIT/LIGO Lab)

Observatories and Collaborations

LIGO has two widely separated identical detector sites working in unison as a single “observatory”: one in southeastern Washington State and the other in rural Livingston, Louisiana. In 2015, both detectors completed major upgrades that increased LIGO’s sensitivity more than ten times over the original instrument.

While LIGO could not function without the coordination between the Hanford and Livingston detectors, an equally important collaboration exists between LIGO and a network of other gravitational wave observatories and researchers around the world. Most prominently, LIGO closely collaborates with Virgo, a 3 km gravitational wave interferometer located near Pisa Italy. Data from LIGO and Virgo are combined and analyzed jointly by the LIGO and Virgo groups. This collaboration significantly enhances the search for gravitational waves. Learn more about LIGO's two detectors sites and the observatory’s collaborative relationships by clicking on the links below: