Astronomers have identified a supermassive black hole that absorbs the equivalent of one Sun per day, at the heart of the brightest quasar ever observed, according to a study published in Nature.
“We have discovered the fastest-growing black hole known to date. It has a mass of 17 billion suns and ‘eats’ just over one sun a day,” Christian Wolf, an astronomer at the Australian National University (ANU) and lead author of the study, explained in a statement from the European Southern Observatory (ESO).
Invisible by definition, a supermassive black hole illuminates the nucleus of the galaxy that houses it through its activity. This nucleus is called a quasar, and the one observed by ESO’s Very Large Telescope (VLT, located in Chile) is “the brightest object in the known universe,” according to Wolf.
Its light took 12 billion years to reach the instruments of the VLT, which makes it possible to date its existence to the early epoch of the Universe – 13.8 billion years old.
The light from J0529-4351, as it has been called, had been detected as early as the 1980s, according to the study published Monday. But an automatic analysis of data from the Gaia satellite, which maps the galaxy, had likened it to a very bright star.
Researchers using the Siding Spring Observatory in Australia and the VLT’s X-shooter instrument identified it last year as a quasar.
The supermassive black hole it hosts attracts a colossal amount of matter, accelerated to no less rapid speeds, emitting light equivalent to that of more than 500 billion suns, according to the ESO statement.
The existence of such a massive and luminous object in the early universe “is difficult to explain,” notes the study, which recalls the discovery of similar quasars in recent years.
Their existence each time assumes the rapid growth of a supermassive black hole, which theory is still difficult to describe.
A black hole is supposed to be born as a result of the explosion of a star at the end of its life, whose core then collapses in on itself. It can grow by feeding on the matter around it, attracted by its gravitational field.
Scientists are wondering about the process at work that allows a black hole to become supermassive in a relatively short time in the early Universe.