January 12, 2011 - Wired
The black hole in the nearby galaxy M87 weighs in at 6.6 billion suns, making it the local universe’s heavyweight champ.
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To pin down the monstrous black hole’s mass, Gebhardt and his colleagues used the Gemini North telescope atop Mauna Kea in Hawaii to measure the speeds of stars zipping past the galactic center.
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