Japanese astronomers discover second largest black hole in Milky Way

Astronomers contend that they might have found the second largest black hole in the Milky Way, which is said to have a mass nearly 100,000 times that of the sun. The invisible black hole was unearthed by the Nobeyama 45-m Radio Telescope located in Japan and was detected at the center of our Milky Way Galaxy.

Tomoharu Oka, a professor at Keio University in Japan and his team of astronomers, found a mysterious gas cloud, called CO-0.40-0.22, about 200 light years from the center of the Milky Way. What made this cloud of gas strange was its astonishingly wide velocity dispersion.

The cloud contains gas with a wide range of speed. This mysterious feature was unearthed by two radio telescopes, one the Nobeyama 45-m Telescope in Japan and the other, ASTE Telescope in Chile both of which were operated by National Astronomical Observatory of Japan.

The team observed the CO-0.40-0.22 closely with the Nobeyama 45-m Telescope and found that it gave 21 emission lines from 18 molecules. The cloud had an elliptical shape and were composed of two components – a compact, low-density component with a wide velocity range of 100km/s and a dense component, which was ten light years long and had a narrow velocity dispersion.

To test the cause of the dispersion in velocity caused by the black hole, astronomers constructed a computer simulation of the gas cloud with a gravity strength equivalent to 100,000 times that of the sun. The simulation matched the observed data of gas cloud. Since there is no solid objects are seen in the X-ray or the infrared observation, the best guess is that it is a black hole.

The research team hopes to study this black hole with intermediate mass to better understand the birth of supermassive black holes in the centers of the galaxy.