The most luminous object ever detected has been observed in the distant Universe.
This object, known as J0529-4351, is a quasar, which is the bright core of a galaxy powered by an enormous black hole that is 17 billion times the mass of our Sun.
The object’s immense power was confirmed through observations made by the Very Large Telescope in Chile.
Scientists, reporting in the journal Nature Astronomy, say the black hole has a voracious appetite, consuming the mass equivalent to one Sun every day.
J0529-4351 was actually recorded in data many years ago but its true glory has only just been recognised.
“We have discovered an object which has previously not been recognised for what it is; it’s been staring into our eyes for many years because it’s been glowing at its brightness for longer than humankind has probably existed. But we’ve now recognised it, not as being one of the many foreground stars in our Milky Way but as a very distant object,” Christian Wolf, from the Australian National University (ANU), told BBC News.
A quasar is a type of Active Galactic Nucleus (AGN), identified by astronomers as the highly energetic core of a galaxy. It is powered by an enormous black hole that is actively pulling matter towards itself at an incredibly rapid rate.
As this matter is drawn into the black hole, it is accelerated and torn apart, emitting a vast amount of light. This emission is so intense that even an object as distant as J0529-4351, located billions of light-years away, is still observable to us.
The light from this quasar has traveled an astonishing 12 billion years to reach the detectors at the Very Large Telescope (VLT), which is part of the European Southern Observatory organization.
Overall, the characteristics of this object are truly remarkable.
“What is unusual is the rate at which it’s digesting other material; you know, swallowing mass. And that’s at the rate of about one Sun – one solar mass – per day, which is an enormous rate. And that makes it very, very luminous,” said Rachel Webster from the University of Melbourne.
The brightness of this quasar is estimated to be equivalent to more than 500 trillion suns. The hot accretion disc responsible for this luminosity measures about seven light-years in diameter, approximately 15,000 times the distance from the Sun to the orbit of Neptune.
The presence of supermassive objects at the cores of all galaxies suggests that these entities play a fundamental role in the evolution of galaxies.
“In simple language, it means that without these black holes, our galaxy as we know it wouldn’t be what it is today. In fact, all galaxies would be very different without their supermassive black holes. In fact, it may even be possible that all galaxies form around these supermassive black holes,” ANU PhD student and co-author Samuel Lai said.
The puzzle is how some of the black holes got so big so early in the Universe. This is leading scientists to consider a scenario in which the objects grew directly out of the gas that existed just after the Big Bang, perhaps even before the first stars formed.
