Pune scientists discover closest ‘binary supermassive black hole’ in spiral galaxy
The discovery made by Preeti Kharb and Dharam Vir Lal from NCRA-TIFR along with David Merritt from Rochester Institute of Technology (RIT), USA, was published in the journal Nature Astronomy, on September 18, 2017.pune Updated: Sep 20, 2017 00:32 IST
In a major astronomical discovery, scientists from the city-based National Centre for Radio Astrophysics (NCRA) and Tata Institute of Fundamental Research (TIFR) have reported the finding of the closest ever binary supermassive black hole system in a spiral galaxy.
“What sets this discovery apart from the rest is that this one is the closest and is found in a spiral galaxy named NGC 7674. Binary supermassive black hole systems are otherwise commonly found in elliptical galaxies,” Dharam Vir Lal, NCRA scientist and member of the team said, while speaking to Hindustan Times.
The discovery made by Preeti Kharb and Dharam Vir Lal from NCRA-TIFR along with David Merritt from Rochester Institute of Technology (RIT), USA, was published in the journal Nature Astronomy, on September 18, 2017.
Lal said this discovery was significant as it is the direct observational proof of the existence of close supermassive black hole binary systems in galaxies, which are said to be the potential sources of gravitational waves.
“This particular binary supermassive black hole system is located about 400 million light years from earth. The separation of the two black holes in the binary system is less than one light year, which is actually much less than the previous record holder.
“It was a black hole binary with a separation of about 24 light years,” he added.
The binary system had been detected using a technique called very long baseline interferometry (VLBI) in which separate radio telescopes around the world can work together as a single large telescope, Lal explained.
“The discovery of this binary supermassive black hole in this galaxy confirms a theoretical prediction that such binaries should be present in so-called Z-shaped radio sources,” he further added.