Two Indian scientists from the National Centre for Radio Astrophysics (NCRA), Tata Institute of Fundamental Research (TIFR) have spotted a pair of supermassive black holes, which is the closest one discovered so far.
Here are the top things to know about this finding:
1. Situated in an active spiral galaxy dubbed as NGC 7674 (Mrk 533), this binary supermassive black hole system is located 400 million light years away from Earth. Unlike the normal galaxies which emit light uniformly, active galaxies are known to radiate intensely at their centre.
2. Preeti Kharb and Dharam Vir Lal from NCRA, along with David Merritt from Rochester Institute of Technology, USA made this unique discovery. Such binary black hole systems are known to be present only in elliptical galaxies.
"Elliptical galaxies are formed when two spiral galaxies collide and merge. They possess one super massive black hole located in its centre. But, in this case, it is a binary super massive black hole inside a spiral galaxy, never known so far," said Lal, as quoted by an Indian Express report.
3. The astronomers found that the two black holes are at a distance of just one light year away from each-other.
"The previous recorded separation of a black hole binary was about 24 light years," Kharb stated, according to a TOI report.
4. The researchers claim that this newly discovered binary supermassive black hole system could be one of the objects from which the radio jet speed could be calculated. Radio jet refers to materials emitted from the centre of galaxies at super fast pace – almost equal to the speed of light, they even spew strong radio waves.
5. High resolution images of this object were captured with the help of a technique known as very long baseline interferometry, which were examined by Kharb since April 2017.
6. Images of the spiral galaxy NGC 7674 were captured in different frequencies -- 2GHz, 5 GHz, 8GHz and 15 GHz. The astronomers identified the prevailing proximity between the two black holes with the help of the high resolution provided by 10 dish antennas which are situated in the US.
"The powerful antennas, across a distance of 8,900 kms in the US, was used to image this object, that clearly confirmed the one light year separation between the two massive black holes," Lal told Indian Express.
7. The researchers will now try digging out the present theoretical models to find out an explanation behind the presence of the two supermassive black holes in the spiral galaxy. "Now, whenever there is a merger of two spiral galaxies, it will in reality be the merger of three bodies instead, presenting a completely newer kind of a problem to be solved," Lal stated.