JWST Detects Most Distant, Active Supermassive Black Hole to Date
Colby astronomers using the James Webb Space Telescope also detected other distant black holes and early galaxies for the first time
The universe is teeming with black holes. Colby astronomers Dale Kocevski and Elizabeth McGrath are among researchers using the James Webb Space Telescope who have confirmed black holes existed in the universe earlier than previously known.
The Colby scientists and the international team behind the Cosmic Evolution Early Release Science (CEERS) Survey have discovered the most distant, active, supermassive black hole to date with the James Webb Space Telescope, or JWST. Known as CEERS 1019, the black hole existed just over 570 million years after the Big Bang.
Using the telescope’s highly detailed images and data, the team also discovered two lower-mass black holes that existed 1 and 1.1 billion years after the Big Bang. Kocevski was the lead author of a recently published paper that identified these objects, named CEERS 746 and CEERS 2782. Additionally, the researchers teased out of the data 11 extremely distant galaxies that existed when the universe was 470 to 675 million years old.
It’s a jackpot of discoveries that surprised even the researchers.
“Our findings show that growing black holes in infant galaxies are very common in the early universe,” said Kocevski, associate professor of astronomy and physics. “This was something that we did not expect to detect with our observations. We knew lower-mass black holes had to exist in early galaxies, but we didn’t think we could find them.”
The expansive CEERS survey combined the space telescope’s near- and mid-infrared images and highly detailed data known as spectra to make these recent discoveries. The telescope’s powerful capabilities are moving astronomy research out of the theoretical and into the measurable realm.
“JWST has proven even more sensitive than we previously thought,” said Kocevski.
How did CEERS 1019 form?
Black holes are massive gravity wells that contain tremendous amounts of matter pulled into extremely small areas. The resulting gravitational field is so strong that nothing, not even light, can escape. The universe is peppered with smaller black holes, usually formed as the result of large, dying stars, while supermassive black holes reside at the center of virtually all large galaxies.
Kocevski, who’s studied the growth of black holes for 15 years, said that presently researchers don’t know where supermassive black holes come from. It’s unclear how they form and how they reach their extraordinary masses, a million to a billion times the mass of the sun.
According to a NASA press release, CEERS 1019 is not only notable for how long ago it existed but also for how little it weighs. This black hole clocks in at about 10 million solar masses, far less than other distant black holes detected by other telescopes. Those behemoths typically weigh more than one billion times the mass of the Sun—and they’re easier to detect because they’re much brighter. CEERS 1019 is more similar to the black hole at the center of our Milky Way galaxy, which is 4.6 million times the mass of the Sun. The newly discovered black hole is also not as bright as more massive black holes previously detected.
Because CEERS 1019 is found only 570 million years after the Big Bang, its relatively young age constrains how it must have formed. There are just two scenarios that could explain its formation, Kocevski said.
“It could only have formed from the direct collapse of a massive gas cloud before galaxies themselves existed, or it formed as a result of a supernova of a very massive star (much more massive than the stars that exist today) and then grew at rates that exceed our theoretical limit on how fast we think black holes can grow.
“If the former is true, researchers have learned something about what came before galaxies. If the latter is correct, there’s something not yet understood about how black holes grow.”
Kocevski said there are several theories about black hole formation, and the key to testing these formation scenarios is to find low-mass black holes as early in the universe as possible. That is why the discovery of CEERS 746 and CEERS 2782 is so important.
Discoveries await
As part of NASA’s Early Release Science Program, the CEERS team was one of the first to receive data from the JWST in August 2022. In the intervening months, Kocevski and McGrath, also an associate professor of astronomy and physics, have made tremendous progress learning how to process and analyze its data.
“The most exciting development is the realization that we can use our JWST spectroscopy to identify low-mass black holes in galaxies,” said Kocevski. “This surprised many of us. We simply didn’t think our data would pick up such systems.”
JWST’s ability to capture that category of black holes so clearly is a boon for researchers like Colby’s astronomers.
“Now we think that lower-mass black holes might be all over the place,” said Kocevski, “waiting to be discovered.”
