Team of astronomers by University of Maryland has succeeded in accurately measuring and thus confirming the existence of a black hole about 400 times the mass of our sun in a galaxy 12 million light years from Earth.
Beginning in 1999 a NASA satellite telescope, the Chandra X-ray Observatory, detected X-rays in Messier 82 from a bright object prosaically dubbed M82 X-1. Astronomers, including Richard Mushotzky, a UMD astronomy professor and co-author Tod Strohmayer of NASA's Goddard Space Flight Center, suspected for about a decade that the object was an intermediate-mass black hole, but estimates of its mass were not definitive enough to confirm that.
Between 2004 and 2010 NASA's Rossi X-Ray Timing Explorer (RXTE) satellite telescope observed M82 X-1 about 800 times, recording individual x-ray particles emitted by the object. It was found among the material circling the suspected black hole; two repeating flares of light were spotted. The flares showed a rhythmic pattern of light pulses, one occurring 5.1 times per second and the other 3.3 times per second or a ratio of 3:2.
Dheeraj Pasham, astronomy graduate student from University of Maryland, used the oscillations to estimate that M82 X-1 was 428 times the mass of the sun, give or take 105 solar masses; however, he did not proposed an explanation for how this class of black holes formed.
The study is published online in the journal Nature.