BENGALURU: Indian astronomers have reported one of the strongest flares from a feeding supermassive black hole or blazar called BL Lacertae, some 10 million light-years away. And, the analysis of the flare from this blazar — one of the oldest astronomical objects — can help trace the mass of the black hole and the source of this emission.
This, the team believes can provide a lead to probe into mysteries and trace events at different stages of evolution of the Universe.
A team of astronomers led by Alok Chandra Gupta from the Aryabhatta Research Institute of Observational Sciences (ARIES) had been following the blazar since October 2020 as part of an international observational campaign. The team detected the exceptionally high flare on January 16, 2021, with the help of Sampurnanand Telescope (ST) and 1.3m Devasthal Fast Optical Telescopes located in Nainital.
“This class of objects is very unique. They have complete electromagnetic emission, that is they emit radiation in all electromagnetic bands — Radio Waves; Microwaves; Infrared; Visible Light; Ultraviolet (UV); X-Rays and Gamma Rays — which is not something all objects can do. Gamma ray births do this, but they are short lived,” Gupta told TOI.
He said that these objects are most distant, meaning they were formed in the very early stage of universe formation. “While there are more than a billion agents/sources that astronomers have detected over the years, these objects are very rare. Till date, only about 5,000 blazars are known. And, of these, only about 50 are prominent, allowing continuous/long-term observation,” he added.
According to the department of science and technology (DST), Blazars or feeding supermassive black holes in the heart of distant galaxies receive a lot of attention from the astronomical community because of their complicated emission mechanism. “They emit jets of charged particles traveling nearly at the speed of light and are one of the most luminous and energetic objects in the Universe,” the DST said.
“BL Lacertae blazar is 10 million light-years away and is among the 50 most prominent blazars that can be observed with the help of a relatively small telescope. It was among the three to four blazars that was predicted to be experiencing flares by the Whole Earth Blazar Telescope (WEBT), an international consortium of astronomers,” Gupta said.
The data collected from the flare observed will help calculation of the black hole mass, size of emission region, and mechanism of the emission from one of the oldest astronomical objects known, hence opening a door to the origin and evolution of the Universe.