LIGO Announces the First Detection of Gravitational Waves
National Press Club, 529, 14th Street Northwest, Downtown, Ward 2, Washington, District of Columbia, 20005, United States
LIGO
CONFIRMÉCONFIANCE 88 %Wikipedia[2] dates both the observation and the announcement: "The first direct observation of gravitational waves was made on 14 September 2015 and was announced by the LIGO[3] and Virgo collaborations on 11 February 2016." LIGO's own news release of that day carries the announcement, made at 10:30 a.m. Eastern at the National Press Club, where this pin is placed.
At a press conference at the National Press Club in Washington, the LIGO and Virgo collaborations announce GW150914, a signal from the merger of two black holes recorded by both LIGO detectors on 14 September 2015 - the first direct observation of gravitational waves.
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