Astronomers discover a quiet black hole with help of gas cloud

Black holes have always been a puzzle for the astronomers, as we are yet to understand their growth. The scientists have managed to find small and big black holes but never came across an intermediate one. The smallest black holes found until now are around five times the Sun's mass, while the larger ones are hundreds or thousands of times the mass of our prime star.

Looking for a black hole is a tough task as they do not emit light, but they do churn out energy which can be detected. However, there are some black holes which emit very little energy called 'quiet' black holes.

Now a team of Japanese astronomers has located a quiet black hole by observing a cloud of gas near. They noticed that the cloud was moving strangely at the center of the galaxy. The team used an instrument called ALMA (Atacama Large Millimeter/submillimeter Array) to observe the gas cloud which is 25,000 light years away. They noticed that the cloud had a gravitational pull of a massive body.

"Detailed kinematic analyses revealed that an enormous mass, 30,000 times that of the Sun, was concentrated in a region much smaller than our Solar System," leader of the research team, Shunya Takekawa said in a statement. "This and the lack of any observed object at that location strongly suggests an intermediate-mass black hole."

The black hole is likely to be consumed by a bigger black hole in the same way it gobbles other matter. "It is significant that this intermediate mass black hole was found only 20 light-years from the supermassive black hole at the Galactic center," explains Tomoharu Oka, a professor at Keio University. "In the future, it will fall into the supermassive black hole; much like gas is currently falling into it."

"By analyzing other anomalous clouds, we hope to expose other quiet black holes," he added.