Astronomers have discovered a distant, massive and ancient black hole that calls into question current models for the early expansion of the universe. A team of scientists from China and Arizona spotted the brightest quasar from the early universe, named SDSS J0100+2802, centered on a black hole 12.8 billion light years away and as bright as 420 trillion suns.
Quasars are celestial objects that are essentially very bright clouds of material being swallowed by a black hole. The material accelerates toward the black hole and heats up in the process, causing it to glow brightly.
The existence of such a powerful and ancient object presents something of a puzzle for scientists because it formed less than a billion years after the Big Bang, when the universe was relatively young.
"How can a quasar so luminous, and a black hole so massive, form so early in the history of the universe, at an era soon after the earliest stars and galaxies have just emerged?" said Xiaohui Fan, Professor of Astronomy at the University of Arizona, who co-authored a study on the discovery published in the journal Nature this week. "By comparison, our own Milky Way galaxy has a black hole with a mass of only 4 million solar masses at its center; the black hole that powers this new quasar is 3,000 time heavier."
Team member Dr. Fuyan Bian, from the Australian National University (ANU), said the interaction between a black hole and a surrounding quasar creates radiation pressure that is believed to limit the growth of black holes. "However this black hole at the center of the quasar gained enormous mass in a short period of time," Dr. Bian said. "Forming such a large black hole so quickly is hard to interpret with current theories."
At the time the light from this particular quasar first started making its way towards Earth, it was near the end of what astronomers call the "epoch of reionization" – the period in which light from early galaxies and quasars was just beginning to cut through the vast darkness, creating the universe of seemingly countless distant points of light we know today.
Astronomers have cataloged over 200,000 quasars since their discovery in 1963. The oldest discovered so far dates to just 700 millions years after the Big Bang, just a few hundred million years older than SDSS J0100+2802.
"This quasar is very unique," said Xue-Bing Wu, the associate director of the Kavli Institute of Astronomy and Astrophysics. "Just like the brightest lighthouse in the distant universe, its glowing light will help us to probe more about the early universe."
The quasar was spotted first by the Lijiang Telescope in the Himalayan foothills of Yunnan, China. Arizona's Large Binocular Telescope and Multiple Mirror Telescope then helped determine the distance and mass of the black hole. Additional observations from observatories in Chile and Hawaii confirmed the results.
The Nature article was published online February 25.
Sources: University of Arizona, Australian National University
