James Webb discovers universe’s oldest black hole

Scientists have found the earliest black hole in the universe that existed just 500 million years after the Big Bang. The discovery was revealed in a new paper published in The Astrophysical Journal Letters. The ancient black hole was spotted by the James Webb Space Telescope in the distant galaxy CAPERS-LRD-z9, shrouded by gas. It is around 13.3 billion years old, when the universe was just three per cent of its current age. CAPERS-LRD-z9 is one of the “little red dot” galaxies that Webb captured in the first year of its launch. They looked very different from the galaxies Hubble was used to seeing. Steven Finkelstein, co-author of the new study and director of the Cosmic Frontier Center at the University of Texas at Austin, said in a statement, “The discovery of Little Red Dots was a major surprise from early JWST data, as they looked nothing like galaxies seen with the Hubble Space Telescope.”

These galaxies appeared as scarlet pinpricks in Webb’s vision and had never been detected by any telescope before it. Their discovery changed the beliefs scientists had about the universe. NASA stated that if these shining objects were galaxies, then it would imply that some of them had grown really big, really fast and did not fit into the current theories. Finkelstein and his team compiled data on these little red dot galaxies and published their findings in January. It included all of them that existed in the first 1.5 billion years after the Big Bang. They wrote that these galaxies likely had supermassive black holes that were still growing. He then collaborated with a team led by Anthony Taylor, a postdoctoral researcher at the Cosmic Frontier Center.

They checked the spectroscopy data from Webb’s CAPERS (CANDELS-Area Prism Epoch of Reionization Survey) program. They noticed a distinct spectroscopic signature that is produced when black holes interact with gas clouds. As the gas rapidly swirls around and falls into a black hole, light from gas that is moving away from us stretches into redder wavelengths, while the one moving towards us has bluer wavelengths. Taylor says, “There aren’t many other things that create this signature.” This one turned out to be the earliest such example.

Their findings further cement the belief that supermassive black holes are the likely source of the brightness emitted by these galaxies. “We’ve seen these clouds in other galaxies,” Taylor said. “When we compared this object to those other sources, it was a dead ringer.” The oldest black hole discovered at the centre of this galaxy is up to 300 million times more massive than the Sun. “Finding a black hole of this size that existed so early on in the universe adds to growing evidence that early black holes grew much faster than we thought possible,” Finkelstein said.