MSNBC - December 5, 2011
Scientists have discovered the largest black holes yet, and they're far bigger than researchers expected based on the galaxies in which they were found.
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The scientists used the Gemini and Keck observatories in Hawaii and the McDonald Observatory in Texas to monitor the velocities of stars orbiting around the centers of a pair of galaxies. These velocities reveal the strength of the gravitational pull on those stars, which in turn is linked with the masses of the black holes lurking there.
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