Only 4% of the sky is visible
These black holes are created by the bursting of dying stars or collision of neutron stars and because of this, space-time changes. Their gravitational force is so high that even light cannot come out of them. Astronomers have prepared a map showing a SBH with a white dot on a black background. This map is printed in Astronomy and Astrophysics. There are 25000 SBH visible while there are more SBH in the universe. Indeed, the data that make up this map is derived from just 4% of the northern hemisphere’s sky.
How to create a map?
The team has prepared this map with the help of 52 low-frequency telescope LOFAR. These telescopes detect radio emissions from matter that are very close to the SBH. Chief Researcher Francesco di Gasparine has said that this result has come after many years of hard work on extremely difficult data. Radio signals were invented to capture images in the sky. This map is made by combining 265 hours of data from the sky of the Northern Hemisphere. The Earth’s ionosphere layer affects radio waves, making observation difficult.
How are SBHs made?
These theories are believed to have originated with the Big-Bang under a theory called the Direct Collapse (Direct Collaps). According to this, a minimum size of huge SMBHs was born, whose mass was millions of times more than our sun. According to the second theory, SMBH was born long after the big-bang from a blackhole made from the death of a huge star. In this case, initially SMBH would be a few thousand times more in mass than the sun and later it became more massive due to the inclusion of nearby stars and gas.