Second Largest Black Hole in the Milky Way

Most galaxies have one “supermassive” black hole in their heart, and until now, only a handful of galaxies harboring two black holes have been observed.

Astronomers recently discovered clues of an invisible black hole detected at a mass 100 times that of the Sun at the center of the Milky Way according to a Phys.org account. Researchers had spotted a unusual gas cloud codenamed CO-0.40-0.22, with the gas moving at varying rates of speed, and with the help of the Nobeyama 45-m telescope, were able to see the cloud up closer.

With the help of the telescopes, scientists have found a “smoking gun” near the galactic center. One that has a low density but it is very fast in dispersing at about 100 km per second and another that is denser, extending about 10 light-years with a low velocity dispersion. The gas cloud, named CO-0.40-0.22, has an elliptical shape and has properties that suggest it may contain black holes. As it happens to be that many individuals believe that only when we can completely understand the intermediate black hole that is when our knowledge about the fully grown ones will grow. Oka said, “As far as we know, the best candidate for the compact massive object is a black hole”.

The researchers used the Nobeyama 45-meter radio telescope to find the black hole, which could introduce a new method for seeking out black holes. It is an indication that velocity dispersion is not triggered by a local energy input like supernova explosion.

Supermassive black holes can have anywhere between a few million and a few billion solar masses, and are present at the center of all galaxies.

The team of astronomers also conducted a simulation of clouds using a gravity source. During the simulation, the gas clouds were first attracted by the source, and then, their speed went up when they approached it, and reached maximum at the nearest point to the object.

“These results open a new way to search for black holes with radio telescopes”, the observatory said, in the statement.

If proven accurate, their detection could be the first discovery of an intermediate mass black hole (IMBH). But this raises a problem because so far no firm observational evidence for intermediate mass black holes has been found. If the cloud CO-0.40-0.22, located only 200 light years away from Sgr A* (the 400 million solar mass SMBH at the center of the Milky Way), contains an intermediate mass black hole, it might support the intermediate mass black hole merger scenario of SMBH evolution.