New Delhi: Astronomers have detected a rapidly growing black hole at a distance of about 12.8 billion lightyears from the Earth, designated as RACS J0320-35. This black hole is growing at among the fastest rates known for a black hole, and contains about a billion times the mass of the Sun. It is also the brightest black hole in X-rays from the first billion years of the universe, and reached its mass within 920 million years of the Big Bang. The black hole is powering a quasar, a superheated disc of infalling material that can outshine all the stars in a galaxy, similar to active galactic nuclei (AGNs), but from the infancy of the universe. The fastest growing black hole is designated as J059-4351, contains 17 billion solar masses, is growing by a solar mass every day and is at a distance of 12 billion kilometres.
Data captured by NASA’s Chandra X-ray observatory allowed astronomers to determine the rate at which the black hole is consuming the surrounding material. As matter is pulled inwards, the extreme friction causes the tortured infalling material to emit radiation across the electromagnetic spectrum. This radiation puts an outward pressure on the infalling material, and can build up to balance out the gravity of the black hole. The maximum extent of this pressure is called the Eddington Limit. RACS J0320-35 is consuming matter at 2.5 times the Eddington Limit.
Mechanisms of Black Hole Formation
Scientists believe that black holes growing slower than the Eddington Limit need to start out big, containing as much mass as 10,000 Suns to reach a billion solar mass within the first billion years after the Big Bang. Instead of a series of mergers between stellar mass black holes produced by the violent deaths of massive stars, such black holes could be born from the direct collapse of entire stellar nurseries, without going through a star stage first. RACS J0320-35 is growing at a rate of between 300 and 3,000 solar masses a year. The observations by Chandra are consistent with a black hole growing faster than the Eddington Limit. A paper describing the findings has been published in The Astrophysical Journal.