A quasar is an active galaxy nuclei are composed of a supermassive black hole around which huge amounts of matter gravitate.
A team of astronomers has discovered the most brilliant quasar ever seen. Called J043947.08 + 163415.7, this celestial object is 600 billion times brighter than our Sun, explain the scientists in their study, published in The Astrophysical Journal Letters. “We do not expect to find many more brightest quasars in the rest of the observable universe,” said Xiaohui Fan, professor of astronomy at the University of Arizona and lead author of the study, in a press release.
Quasars, celestial objects among the brightest in the universe, consist of three main elements. A supermassive black hole located in the center and composing almost all of its mass, an accretion disk formed by the material absorbed by the black hole and gas jets expelled from the accretion disk. They are also called active galaxy nuclei (AGN) since they are at the origin of the formation of galaxies.
According to astronomers’ calculations, J043947.08 + 163415.7 is 12.8 billion light-years away from Earth. The researchers thus observed the quasar as it was at the time when the universe – now 13.75 billion years old – was barely a billion years old. The interest of this discovery, beyond the record brightness of this object, is to open a window on the past and how supermassive black holes have influenced the formation of stars and galaxies at the beginning of the universe.
The team of scientists was able to detect J043947.08 + 163415.7 thanks to numerous telescopes located on the islands of Hawaii including the Gemini observatory, the James Clerk Maxwell Telescope (JCMT), the United Kingdom Infra-Red Telescope (UKIRT), the WM Keck, the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1) as well as the Hubble Space Telescope. But even with these high-tech equipment, they could never have found it without the help of the gravitational field of a galaxy located between the Earth and the quasar that multiplied its brightness by 50 thanks to a mechanism called “gravitational lens”.
“This detection is as surprising as it is major, for decades we thought that these quasars [detected by gravitational lenses] should be very common in the primitive universe, but this is the first of its kind we have found, details Fabio Pacucci, a researcher from Yale University who participated in the study. “Our discovery gives us a clue as to how to find others,” he added.
In their study, the researchers indicate that their “theoretical model” predicts that there could be a “substantial” number of quasars of the same type. “If they are really numerous, it would revolutionize our idea of what happened right after the Big Bang, and could even change our vision of the process of forming these cosmic monsters [the supermassive black holes] and the way they grew”. In the meantime, there is no doubt that many scientists will carry out further studies on J043947.08 + 163415.7 and perhaps lift the veil on the mysteries of the formation of our Universe.