Far Beats

The first direct gravitational wave observation was made on 14 September 2015 and was announced by the LIGO and Virgo interferometer collaborations on 11 February 2016. The waveform, detected by both LIGO observatories, matched the predictions of general relativity for a gravitational wave emanating from the inward spiral and merger of a pair of black holes and subsequent “ringdown” of the single resulting black hole. The signal was named GW150914 (i.e., “Gravitational Wave 2015–09–14“). This was also the first observation of a binary black hole merger, demonstrating the existence of binary stellar-mass black hole systems, and that such mergers could occur within the current age of the universe. This first observation was reported around the world as a remarkable accomplishment for many reasons. Efforts to prove the existence of such waves had been ongoing for over fifty years, and the waves are so minuscule that Einstein doubted they could ever be detected. The waves given off by the cataclysmic merger of G