Space.com - June 8, 2009
The most massive black hole yet weighed lurks at the heart of the relatively nearby giant galaxy M87.
The supermassive black hole is two to three times heftier than previously thought, a new model showed, weighing in at a whopping 6.4 billion times the mass of the sun. The new measure suggests that other black holes in nearby large galaxies could also be much heftier than current measurements suggest, and it could help astronomers solve a longstanding puzzle about galaxy development.
"We did not expect it at all," said team member Karl Gebhardt of the University of Texas at Austin.
The discovery was announced here today at the 214th meeting of the American Astronomical Society.
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While the new mass of M87 is based on a model, recent observations from the Gemini North Telescope in Hawaii and the European Southern Observatory's Very Large Telescope in Chile support the model findings.
The study of M87's mass will also be detailed later this summer in the journal Astrophysical Journal.