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GW150914

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Gravitational wave observation GW150914 with black hole merger simulation

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Warped Spacetime and Horizons of GW150914

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LIGO GW150914 Black Hole Merger event sounds

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Numerical Simulation of GW150914

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GW150914: Waves and spacetime diagram of black holes

The first direct observation of gravitational waves was made on 14 September 2015 and was announced by the LIGO and Virgo collaborations on 11 February 2016. Previously, gravitational waves had only been inferred indirectly, via their effect on the timing of pulsars in binary star systems. 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 of around 36 and 29 solar masses and the subsequent "ringdown" of the single resulting black hole. The signal was named GW150914. It was also the first observation of a binary black hole merger, demonstrating both the existence of binary stellar-mass black hole systems and the fact that such mergers could occur within the current age of the universe.