NASA | MSFC | SAO | Chandra X-ray Observatory | 2018 Jun 18
found evidence for the existence of an intermediate-mass black hole (IMBH).
Scientists have strong evidence for the existence of stellar black holes, which are typically five to 30 times as massive as the Sun. They have also discovered that supermassive black holes with masses as large as billions of Suns exist in the centers of most galaxies. They have long been searching for IMBHs that would exist in between these two extremes, which would contain thousands of solar masses. Thought to be seeds that will eventually grow to become supermassive, IMBHs are especially elusive, and thus very few robust candidates have ever been found.
One of the few methods scientists can use to try to find an IMBH is to wait for a star to pass close to it and become disrupted. This event causes the black hole to emit a flare that can be observed by telescopes like Chandra. Previously, this kind of event has only been clearly seen at the center of a galaxy before, not at the outer edges.
In this new study led by Dacheng Lin of the University of New Hampshire, scientists identified a possible IMBH in observations of a large galaxy some 740 million light years away.
The image above shows the galaxy named 6dFGS gJ215022.2-055059 in data from NASA's Hubble Space Telescope (yellow), with the X-ray source inferred to contain the IMBH detected by Chandra (purple) on the outskirts. ...
A luminous X-ray outburst from an intermediate-mass black hole in an off-centre star cluster - Dacheng Lin et al