Quasars shine so brightly that they are often referred to as beacons. These are huge black holes and they normally occur at the center of enormous galaxies where they grow bigger by accumulating matter. Due to their brilliance, quasars are also the furthest objects in the universe that we are currently able to study.
Sixty-three new quasars were recently discovered by a team led by Carnegie’s Eduardo Bañados. These date from when the universe was only a billion years old. This discovery nearly doubles the number of ancient quasars previously known and is the biggest sample of such distant quasars presented in a scientific article. Scientists’ ability to glean information from them was limited until now because known ancient quasars were rare. Although scientists have searched for them for decades, they are incredibly difficult to find.
Bañados and his team’s discovery will provide valuable information from the first billion years after the Big Bang. Astronomers are especially interested in this period. The Big Bang created the universe and hot matter exploded everywhere. It then cooled off enough for the first protons and electrons to form and then to merge into hydrogen atoms. The result for a long time was a dark universe. Only once these atomic nuclei formed larger structures, light was able to shine in the universe once again. This happened when gravity condensed the matter and eventually formed the first sources of illumination, possibly including quasars.
There is still a lot that science doesn’t understand about this era when the universe’s became light again. Having more examples of ancient quasars will help scientists better understand what happened in those first billion years after the Big Bang.
Bañados notes that one of the greatest mysteries in astronomy is the formation and evolution of the earliest light sources and structures in the universe. Until now however, conclusive results have been inadequate due to the very small sample size of ancient quasars. The 63 very bright quasars discovered in this study are excellent tools for helping researchers probe the early universe and will improve what we know about the early universe.
The findings will soon be published in The Astrophysical Journal Supplement Series.
Want to learn more about quasars? Watch this interesting lecture: