Chandra X-ray Center - 29 April 2010
New evidence from NASA's Chandra X-ray Observatory and ESA's XMM-Newton strengthens the case that two mid-sized black holes exist close to the center of a nearby starburst galaxy. These "survivor" black holes avoided falling into the center of the galaxy and could be examples of the seeds required for the growth of supermassive black holes in galaxies, including the one in the Milky Way.
For several decades, scientists have had strong evidence for two distinct classes of black hole: the stellar-mass variety with masses about ten times that of the Sun, and the supermassive ones, located at the center of galaxies, that range from hundreds of thousands to billions of solar masses.
But a mystery has remained: what about black holes that are in between?
This composite image of the nearby starburst galaxy M82 shows Chandra X-ray Observatory data in blue, optical data from the Hubble Space Telescope in green and orange, and infrared data from the Spitzer Space Telescope in red. The pullout is a Chandra image that shows the central region of the galaxy and contains two bright X-ray sources of special interest.
M82: "Survivor" Black Holes May Be Mid-Sized
- Astronomers have found evidence for two intermediate-mass black holes in the M82 galaxy.
- It has been a mystery of whether black holes exist with masses in between the stellar mass and supermassive categories.
- Evidence suggests that these two objects avoided falling into the giant black hole at the center of M82.
- It is possible these intermediate-mass black holes are examples of seeds required for the growth of supermassive black holes.