Thursday, 26 February 2015

Giant Black Hole 12 Billion Times Bigger than Sun Discovered

A team of scientists has discovered the brightest quasar in the early universe, powered by the most massive black hole yet known at that time.

The quasar SDSS J0100+2802, which is the one with the most massive black hole and the highest luminosity among all known distant quasars, marks an important step in understanding how quasars, the most powerful objects in the universe, have evolved from the earliest epoch, only 900 million years after the Big Bang, which is thought to have happened 13.7 billion years ago.

The discovery of this ultraluminous quasar, by astronomers from Peking University in China and from the University of Arizona, also presents a major puzzle to the theory of black hole growth at early universe, according to researcher Xiaohui Fan.

 Fan added that this ultraluminous quasar with its supermassive black hole provides a unique laboratory to the study of the mass assembly and galaxy formation around the most massive black holes in the early universe.

The quasar dates from a time close to the end of an important cosmic event that astronomers referred to as the "epoch of reionization," the cosmic dawn when light from the earliest generations of galaxies and quasars is thought to have ended the "cosmic dark ages" and transformed the universe into how we see it today.

Shining with the equivalent of 420 trillion suns, the new quasar is seven times brighter than the most distant quasar known (which is 13 billion years away). It harbors a black hole with mass of 12 billion solar masses, proving it to be the most luminous quasar with the most massive black hole among all the known high redshift (very distant) quasars.

Feige Wang said that the ultraluminous nature of this quasar, which was first discovered by their 2.4-meter Lijiang Telescope in Yunnan, will allow them to make unprecedented measurements of the temperature, ionization state and metal content of the intergalactic medium at the epoch of reionization.

Researcher Xue-Bing Wu added that this quasar is very unique and just like the brightest lighthouse in the distant universe, its glowing light will help them to probe more about the early universe.

The study appears in the journal Nature.