HILO — Astronomers at the Subaru Telescope on Maunakea have discovered 83 supermassive black holes billions of light years from Earth.
The black holes, each surrounded by an extremely luminous disc of gas and dust called a quasar, are all approximately 13 billion light years away.
One of the quasars is the second-most-distant quasar ever discovered, said Subaru public outreach specialist Yuko Kakazu.
The most distant quasar was discovered in 2017 by astronomers at the Max Planck Institute for Astronomy, which was one of several institutions involved in the Subaru discovery.
Kakazu said the team of 48 astronomers, led by Yoshiki Matsuoka from Ehime University in Matsuyama, Japan, used the Subaru Telescope’s wide-field Hyper Suprime-Cam to capture images of a wide swath of the sky over five years. Based on those images, astronomers selected star-like points of light as possible quasars and subjected them to a spectroscopic analysis.
Of the more than 100 quasar candidates, 83 were determined to be quasars, which Kakazu said represents the largest sample of quasars discovered.
Because of the quasars’ extreme distance from Earth, the light detected by the telescope is itself billions of years old, originating from a point in time less than one billion years after the Big Bang.
The discovery of such early-universe objects provides valuable insight into the history of the universe. Kakazu said that the number of quasars discovered indicates that there might have been fewer quasars in the early universe than had been previously believed, casting some doubt on a theory about quasars’ role in shaping the young universe.
“The quasars we discovered will be an interesting subject for further follow-up observations with current and future facilities,” said Matsuoka in a statement.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.
