An international group of astronomers, led by researchers at The University of Texas at Austin’s Cosmic Frontier Center, has confirmed the most distant black hole ever identified. The black hole is located in the galaxy CAPERS-LRD-z9, which existed about 500 million years after the Big Bang. This discovery places it approximately 13.3 billion years in the past, a time when the universe was only 3% of its current age.
“When looking for black holes, this is about as far back as you can practically go. We’re really pushing the boundaries of what current technology can detect,” said Anthony Taylor, a postdoctoral researcher at the Cosmic Frontier Center and lead on the team that made the discovery. Their research was published Aug. 6 in the Astrophysical Journal.
“While astronomers have found a few, more distant candidates,” added Steven Finkelstein, a co-author on the paper and director of the Cosmic Frontier Center, “they have yet to find the distinct spectroscopic signature associated with a black hole.”
To identify black holes, astronomers use spectroscopy to analyze light split into various wavelengths and look for signs of fast-moving gas falling into a black hole. Taylor explained that this produces specific red and blue wavelength shifts: “There aren’t many other things that create this signature. And this galaxy has it!”
The research team relied on data from NASA’s James Webb Space Telescope (JWST), specifically from its CAPERS (CANDELS-Area Prism Epoch of Reionization Survey) program. JWST was launched in 2021 and offers some of the deepest views into space currently available.
“The first goal of CAPERS is to confirm and study the most distant galaxies,” said Mark Dickinson, a co-author on the paper and CAPERS team lead. “JWST spectroscopy is the key to confirming their distances and understanding their physical properties.”
CAPERS-LRD-z9 belongs to a new class of galaxies called “Little Red Dots.” These are small, bright, red galaxies seen only within 1.5 billion years after the Big Bang.
“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,” explained Finkelstein. “Now, we’re in the process of figuring out what they’re like and how they came to be.”
Evidence suggests that supermassive black holes may explain why Little Red Dots are so bright despite existing during an era when large numbers of stars were unlikely to have formed yet.
Black holes can emit significant energy because material falling into them heats up intensely before being consumed. By confirming one in CAPERS-LRD-z9, scientists see a clear example linking these objects’ brightness to supermassive black holes.
The distinctive red color observed in Little Red Dots may result from thick clouds of gas around their central black holes shifting emitted light toward longer wavelengths. Taylor noted: “We’ve seen these clouds in other galaxies. When we compared this object to those other sources, it was a dead ringer.”
The size of this newly discovered black hole stands out—it may be up to 300 million times more massive than our sun and could equal half the total mass found in all stars within its host galaxy.
Such an enormous black hole appearing so soon after cosmic dawn challenges previous ideas about how quickly these objects can grow or how massive they might have been initially formed.
“This adds to growing evidence that early black holes grew much faster than we thought possible,” said Finkelstein. “Or they started out far more massive than our models predict.”
The research team plans further observations using JWST for higher-resolution data on CAPERS-LRD-z9 to better understand early black hole development and their impact on Little Red Dots’ formation.
“This is a good test object for us,” said Taylor. “We haven’t been able to study early black hole evolution until recently, and we are excited to see what we can learn from this unique object.”
Additional information supporting this research came from data collected by DESI (Dark Energy Spectroscopic Instrument) at Kitt Peak National Observatory under NSF NOIRLab programs.
