A quasar powered by a vast black hole 17 times the mass of the sun is most luminous object ever detected, scientists have said.
The staggering scale of the object – lurking in the far reaches of the universe – was confirmed by observations by Chile’s Very Large Telescope.
Known as J0529-4351, it was actually detected years ago – but only now has its significance been confirmed.
Christian Wolf, from the Australian National University (ANU), told BBC News: “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. It has a mass of 17 billion Suns, and eats just over a Sun per day. This makes it the most luminous object in the known Universe.”
The word quasar describes a particular type of Active Galactic Nuclear (AGN) powered by a black hole dragging quantities of matter towards itself.
The matter is ripped apart as it speeds towards the black hole, generating so much light that it is visible even from Earth.
The quasar’s emissions have taken a mind-boggling 12 billion years to reach this planet, said the study, published in Nature Astronomy.
Scientists involved in the study say it is 500 trillion times brighter than the Sun, and is coming from an accretion disc measuring seven light-years in diameter – roughly 15,000 times the distance from the Sun to Neptune.
ANU PhD student and co-author Samuel Lai described it as “the largest accretion disc in the Universe”.
Every galaxy ever studied has a supermassive black hole at the centre, suggesting they are vital for their development.
Mr Lai added: “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.”
Christopher Onken, an astronomer at ANU, and another of the study’s co-authors, said: “It is a surprise that it has remained unknown until today, when we already know about a million less impressive quasars.
“It has literally been staring us in the face until now.”
