Astronomers discover oldest, most distant quasar and supermassive black hole 13 billion light years away
Lurking in a distant region of space, more than 13 billion light years away, is a luminous "quasar" fueled by a supermassive black hole 1.6 billion times more massive than the sun. Astronomers recently spotted the galactic beast, marking the oldest one of its kind.
The ancient quasar, defined as a bright, massive, remote active galactic nucleus emitting huge amounts of energy, has been dubbed J0313-1806 by an international team, led by researchers at the University of Arizona. It dates back to an astounding 670 million years after the Big Bang — when the infant universe was just 5% of its current age.
That makes it the most distant — meaning the earliest — known quasar. The previous record-holding quasar was also recently discovered, in 2017.
J0313-1806 is only 20 million light years farther away than its predecessor, but its supermassive black hole is twice as heavy — challenging known theories on the formation of black holes in the early universe.
The team presented its findings, which will publish in the Astrophysical Journal Letters, at the virtual 237th Meeting of the American Astronomical Society this week.
"This is the earliest evidence of how a supermassive black hole is affecting its host galaxy around it," lead author Feige Wang said in a statement. "From observations of less distant galaxies, we know that this has to happen, but we have never seen it happening so early in the universe."
Scientists believe that supermassive black holes swallow a huge amount of matter, such as gas or stars, to form an accretion disk swirling around itself — creating a quasar. These objects are the brightest in the cosmos due to this huge amount of energy.
The celestial object is also the first of its kind to provide evidence for an outpouring of hot, gaseous wind from its black hole at a fifth of the speed of light — a surprising discovery.
The formation of the quasar, however, remains a bit of a conundrum.
Black holes typically form when a star explodes, dies and collapses, and supermassive black holes grow as black holes merge over time. However, quasars in the early universe are far too young to have become so huge, so quickly, in this way.
The supermassive black hole at the center of J0313-1806 is so large — still growing as it ingests the mass equivalent of about 25 suns each year — it cannot be explained by a number of previous hypotheses.
"This tells you that no matter what you do, the seed of this black hole must have formed by a different mechanism," said co-author Xiaohui Fan. "In this case, one that involves vast quantities of primordial, cold hydrogen gas directly collapsing into a seed black hole."
In that scenario, rather than a star collapsing into a black hole, huge amounts of cold hydrogen gas are responsible instead.
When quasars blast their surroundings, they eliminate much of the cold gas needed for stars to form. Because of this, scientists believe that supermassive black holes at the center of galaxies may be the reason galaxies cease forming new stars.
"We think those supermassive black holes were the reason why many of the big galaxies stopped forming stars at some point," Fan said. "We observe this 'quenching' at lower redshifts, but until now, we didn't know how early this process began in the history of the universe. This quasar is the earliest evidence that quenching may have been happening at very early times."
J0313-1806 pumps out 200 solar masses per year. For comparison, the Milky Way forms stars at the "leisurely pace" of about one solar mass each year.
"This is a relatively high star formation rate, similar to that observed in other quasars of similar age, and it tells us the host galaxy is growing very fast," Wang said.
"These quasars presumably are still in the process of building their supermassive black holes" Fan added. "Over time, the quasar's outflow heats and pushes all the gas out of the galaxy, and then the black hole has nothing left to eat anymore and will stop growing. This is evidence about how these earliest massive galaxies and their quasars grow."
The quasar offers a rare glimpse into galaxy formation at the beginning of the universe, but researchers need a more powerful telescope to study it further. NASA's James Webb Space Telescope, slated to launch this year, will allow a more detailed investigation.
"With ground-based telescopes, we can only see a point source," Wang said. "Future observations could make it possible to resolve the quasar in more detail, show the structure of its outflow and how far the wind extends into its galaxy, and that would give us a much better idea of its evolutionary stage."
