Gravitational waves: A new type of astronomy

Gravitational waves provide key to some of the universe's greatest mysteries

The first time physicists announced that the Laser Interferometer Gravitational-wave Observatory (LIGO) had detected gravitational waves, on September 14, 2015, it was breaking news. The discovery coincided with the 100-year anniversary of Einstein's theory of General Relativity, which predicted the existence of gravitational waves."