January 13, 2011 - Astronomy Now
By making detailed measurements of the black hole that lies in nearby galaxy M87, astronomers have found that its mass is equivalent to 6.6 billion Suns.
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The Near-Infrared Field Spectrograph (NIFS) on the 8-metre Gemini North telescope was used by Karl Gebhardt and Joshua Adams of The University of Texas to track the motions of stars careening around the black hole with ten times greater resolution than previous studies have allowed. Meanwhile, University of Texas graduate student Jeremy Murphy used the VIRUS-P instrument on the Harlan J. Smith Telescope at the university's McDonald Observatory to probe the outer reaches of the galaxy known as the dark halo due to the presence of dark matter.
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