January 13, 2011 - Astronomy.com
Astronomers led by Karl Gebhardt from The University of Texas at Austin have measured the most massive known black hole in our cosmic neighborhood by combining data from a giant telescope in Hawaii and a smaller telescope in Texas. The result is a mass of 6.6 billion Suns for the black hole in the giant elliptical galaxy M87. This enormous mass is the largest ever measured for a black hole using a direct technique. Given its massive size, M87 is the best candidate for future studies to actually "see" a black hole for the first time, rather than relying on indirect evidence of their existence as astronomers have for decades.
Gebhardt led a team of researchers using the 8-meter Gemini North telescope in Hawaii to probe the motions of stars around the black hole in the center of the massive galaxy M87.
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