Astronomy.com - June 8, 2009
Astronomers Karl Gebhardt from The University of Texas at Austin and Jens Thomas from the Max Planck Institute for Extraterrestrial Physics have used new computer modeling techniques to discover that the black hole at the heart of M87, one of the largest nearby giant galaxies, is two to three times more massive than previously thought. Weighing in at 6.4 billion times the Sun's mass, it is the most massive black hole measured with a robust technique, and it suggests that the accepted black hole masses in nearby large galaxies may be off by similar amounts. This has consequences for theories of how galaxies form and grow, and might even solve a long-standing astronomical paradox.
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Today's conclusions are model-based, but Gebhardt also has made new telescope observations of M87 and other galaxies using new powerful instruments on the Gemini North Telescope in Hilo, Hawaii, and the European Southern Observatory's Very Large Telescope in Chile. He said these data support the current model-based conclusions about black hole mass.
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