January 12, 2011 - Discovery
The black hole inside a neighboring galaxy, known as M87, is obese and filled with the equivalent of 6.6 billion of our suns, according to new measurements.
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Gebhardt and colleagues used a light-splitting spectrograph on the eight-meter (26-foot) Gemini North telescope in Hawaii to measure the speeds of stars orbiting M87's black hole. The motions are directly related to the gravitational pull of the black hole. The data was then used to calculate the black hole's mass.
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