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Credit: Robin Dienel/Carnegie Institution for Science
The brightest known object in the universe -a quasar 500tn times brighter than our sun, was “hiding in plain sight”, scientists say.
Australian scientists detected a quasar powered by the fastest growing black hole ever discovered. Its mass is about 17bn times that of our solar system’s sun, and it eats a sun a day.
The light from the celestial object travelled for more than 12bn years to reach Earth.
Australian National University scientists first founded it using a 2.3-metre telescope at the university’s NSW Siding Spring Observatory in Coonabarabran. Then they confirmed the discovery using the European Southern Observatory’s (ESO’s) Very Large Telescope, which has a primary mirror of 8 metres.
The discoveries by the ANU researchers, in collaboration with the ESO, the University of Melbourne, and France’s Sorbonne Université have been published in Nature Astronomy.
The lead author and ANU associate professor, Christian Wolf, said it was the brightest object in the universe, and that its incredible rate of growth meant a “huge release of light and heat” – and that he doubted its record would ever be beaten.
The light is emitted from an “accretion disc” that is seven light years in diameter. That disc is where material is getting dragged into and spiralling around the black hole, before it crosses the event horizon.
As that material crashes into other material it makes huge amount of light and heat.
“It looks like a gigantic and magnetic storm cell with temperatures of 10,000 degrees Celsius, lightning everywhere and winds blowing so fast they would go around Earth in a second,” Wolf said.
“This storm cell is seven light years across, which is 50% more than the distance from our solar system to the next star in the galaxy, Alpha Centauri.”
Co-author, Dr Christopher Onken said it was shocking it had remained undetected for this long, and that it was “hiding in plain sight”.
Wolf said he had two distinct feelings about this finding.
“One part is a bit surprising and awe moment, imagining this hellish place … imagining these situations, and that nature does create something even more absolute than we’ve contemplated previously,” he said.
“The other is a bit of cheeky joy – we found it! Nature does not make it easy, it’s like ‘ah, there you are!’.”
