NEW DELHI: A group of astronomers, including from India, have spotted a very short and powerful burst of high-energy radiation (Gamma-ray) that lasted for about a second and had been racing toward Earth for nearly half the present age of the universe.
Details of discovery of the rare phenomena, published in the journal Nature Astronomy on Monday, will help scientists understand many unknown facts about distant galaxies and the possibility of its occurrence in our own milky way galaxy.
The burst, detected by the NASA’s Fermi Gamma-ray Space Telescope last year, turned out to be one for the record books – the shortest Gamma-ray burst (GRB) caused by the death of a massive star, said the department of science & technology (DST) in a note on the discovery and involvement of Indian astronomers.
The GRBs are among the brightest and most energetic events in the universe, detectable across billions of light-years. GRBs, which occur due to the explosion of stars, produce as much energy as the sun produced during its entire existence.
Asked about its implication if the GRB occurs near earth, Indian scientist Shashi Bhushan Pandey from the DST’s Aryabhatta Research Institute of Observational Sciences (ARIES) said, “If, at all, such astronomical event occurs in our milky way galaxy, not only earth but the entire solar system will be simply blown away.”
Pandey, one of the Indian scientists in the team of astronomers spotting the short event GRB from dying star, told TOI that such discoveries and identification of astronomical events would always help the world understand mysteries behind extinction events of the planet’s history in the past (over 450 million years ago).
Astronomers classify GRBs as long or short based on whether the event lasts for more or less than two seconds. They observe long bursts in association with the demise of massive stars, while the “short bursts” have been linked to a different scenario, said the DST note on the latest discovery.
Named GRB 200826A, the burst is the subject of two papers published in Nature Astronomy on Monday. “We think this event was effectively a fizzle, one that was close to not happening at all. Even so, the burst emitted 14 million times the energy released by the entire Milky Way galaxy over the same amount of time, making it one of the most energetic short-duration GRBs ever seen,” said Tomas Ahumada, a doctoral student at the University of Maryland and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who led one of the papers.
The DST in its note, quoting NASA’s Goddard Space Flight Center, said, “When a star much more massive than the Sun runs out of fuel, its core suddenly collapses and forms a black hole. As matter swirls toward the black hole, some of it escapes in the form of two powerful jets that rush outward at almost the speed of light in opposite directions. Astronomers only detect a GRB when one of these jets happens to point almost directly toward Earth.”