Researchers at the International Centre for Radio Astronomy Research have discovered the largest explosion ever observed in the universe since the Big Bang.
The explosion emanated from a supermassive black hole at the centre of the Ophiuchus galaxy cluster some 390 million light-years from Earth.
Radio emission from electrons that accelerated to almost the speed of light and filled the cavity provided the evidence that an eruption of unprecedented size took place.
Simona Giacintucci, of the Naval Research Laboratory in Washington DC, the lead author of the study, described the blast as an astronomical version of the eruption of Mount St Helens in 1980, which ripped off the top of the volcano. "A key difference is that you could fit 15 Milky Way galaxies in a row into the crater this eruption punched into the cluster's hot gas," she said.
Massive explosion
It was such a violent explosion that it literally punched a hole in the plasma surrounding the black hole, as spotted through X-ray telescope observations of the galaxy cluster.
Galaxy clusters are among the largest structures in the universe held together by gravity, containing thousands of individual galaxies, dark matter and hot gas. At the heart of the Ophiuchus cluster, there is a large galaxy that contains a supermassive black hole with a mass equivalent to 10m suns.
Although black holes are known as sinkholes that consume anything that drifts too close, they also expel prodigious amounts of material and energy. These jets occur when a disk of plasma accretes around the central black hole. When the inward flow reaches a certain limit, a proportion escapes being swallowed by the black hole and is redirected into jets that blast out in two perpendicular beams at close to the speed of light, explains The Guardian.
Scientists at NASA confirm the unprecedented blast
Scientists at NASA were able to confirm the unprecedented blast. "The radio data fit inside the X-rays like a hand in a glove," Maxim Markevitch, of Nasa's Goddard Space Flight Center in Greenbelt, Maryland, and study co-author said. "This is the clincher that tells us an eruption of unprecedented size occurred here," she said in the same statement.
"We've seen outbursts in the centres of galaxies before but this one is really, really massive," Melanie Johnston-Hollitt, professor at the Curtin University node of the International Centre for Radio Astronomy Research and co-author of the paper uploaded to preprint archive arXiv earlier this month, said in a statement.
The possibility of an incredibly powerful Ophiuchus explosion was first raised in 2016 in a study led by Norbert Werner, which examined images captured by NASA's Chandra X-ray Observatory. Werner and his colleagues reported a strangely curved edge in the cluster. However, at the time the possibility of this being caused by an explosion was discounted due to the huge amount of energy required to create such a large cavity, reported Space.com
The scientists calculated that it would take about 5 times 10^54 joules of energy to create such a cavity.
Now, Giacintucci and her colleagues made that determination, after analyzing additional X-ray data from Chandra and Europe's XMM-Newton space telescope, as well as radio information gathered by the Murchison Widefield Array in Australia and the Giant Metrewave Radio Telescope in India.
The combined data show that the curved edge is indeed part of a cavity wall, and it borders an area rich in radio emission.
The research team, though, didn't actually capture the explosion happening in real time. Sadly, the Ophiuchus fireworks appear to be over. The radio data show no evidence for ongoing jet activity, the scientists said.
The discovery was published in the Feb. 27 issue of The Astrophysical Journal.
