Tuesday, February 20, 2024

Bright Light

From the Guardian:

The brightest known object in the universe, a quasar 500tn times brighter than our sun, was “hiding in plain sight”, researchers say.

Australian scientists spotted 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 devours the equivalent of a sun a day.

The light from the celestial object travelled for more than 12bn years to reach Earth.

Australian National University scientists first spotted it using a 2.3-metre telescope at the university’s NSW Siding Spring Observatory in Coonabarabran. They then confirmed the find using the European Southern Observatory’s (ESO’s) Very Large Telescope, which has a primary mirror of 8 metres.

The findings 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 most luminous known 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 smashes into other material it creates vast amounts 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 surprising it had remained undetected for this long, and that it was “hiding in plain sight”.

Twelve billion light-years is a bit of a distance, so I don’t think we have to worry about being sucked into it.