JWST Spots 'Little Red Dots' and Overly Massive Black Holes
The James Webb Telescope is reshaping our understanding of the ancient cosmos, and a new study reveals stars that look young despite their age.
The James Webb Telescope is reshaping our understanding of the ancient cosmos, and a new study reveals stars that look young despite their age.
Astrophysicist Charlotte Mason from the Cosmic Dawn Center in Copenhagen has an unusual habit while pondering cosmic mysteries: she draws. "I'm a pretty visual person. I usually draw a lot of pictures trying to understand what's going on," she told Wired. Her pages are filled with sketches of "little red dots," puzzling objects that the James Webb Space Telescope (JWST) has discovered by the hundreds.
According to a Wired report from August 2, 2026, these enigmatic dots were never seen before the telescope became operational in 2022. Today we know they began appearing in significant numbers roughly 650 million years after the Big Bang.
JWST's findings have sparked a wave of excitement but also confusion among astronomers. "We've almost gone from having too many early galaxies to having too many theories explaining them," said Rachel Somerville, a senior research scientist in galaxy formation at the Flatiron Institute in New York, at a conference in Helsingør, Denmark, in April 2026.
One of the biggest puzzles is supermassive black holes that seem too massive for their age. "We already see black holes with a billion suns growing. To get them that big that fast, you have to do gymnastics," Jenny Greene, an astrophysicist at Princeton University, told Wired.
Scientists are struggling to explain how these black holes grew so quickly. According to Greene, the first stars might have left behind black hole seeds of up to 100 solar masses, but that's not enough. "We know that happens, but it's really, really hard to get them to a billion that fast. You really have to force-feed them," she added.
One possible explanation is the "direct collapse" mechanism, where a massive gas cloud collapses directly into a black hole, forming a seed of about 10,000 solar masses. However, Greene cautions: "The problem with the direct collapse picture is that it requires really Goldilocks conditions." Computer simulations can create such black holes, but not enough of them to explain all observed objects. "When people try to do this on a computer, they can make these direct-collapse black holes, but they can't make enough of them to explain all the black holes we see," Greene explained to Wired.
Wired notes that in 2024, JWST observed a black hole about 1.5 billion years after the Big Bang devouring matter 40 times faster than the Eddington limit. Recently, researchers concluded that one "little red dot," about 750 million years old, is actually a "naked" supermassive black hole with an estimated mass of 50 million solar masses, with no visible surrounding stars.
"There are clearly differences in how black holes grow that we don't fully understand yet. So, for me, the most exciting thing I can do right now is try to understand, physically, what is different?" Greene concluded.
Beyond black holes, JWST has also discovered galaxies that are too bright for their early epoch. The oldest galaxy discovered so far existed just 280 million years after the Big Bang. At the Helsingør conference, Somerville presented new computer simulations that track galaxy formation from redshift 15 (about 270 million years after the Big Bang), when gas inflow begins, to redshift 9 (about 550 million years), when a "beautiful galaxy" forms. "There has been remarkable progress since Webb launched, really in the last year or so, on numerical simulations," Somerville told Wired.
Hakim Atek, an astrophysicist at the Paris Institute of Astrophysics at Sorbonne University, highlights a key discovery from JWST's Mid-Infrared Instrument (MIRI). "The main surprise is the diversity of galaxy properties we see in the early epochs. You expect them to look the same," he told Wired.
Some galaxies appear to have cleared all their interstellar medium, gas, and dust, leaving only bare stars, while others are full of gas. "Some of them, it looks like they've cleared all the interstellar medium that's present, gas and dust. It's like you're looking at just bare stars. Another galaxy is the opposite. It has a lot of gas," Atek explained. By comparing observed galaxies with the best simulated analogs, Atek explains: "We can try to match the best analog of the observed galaxy with the simulated one. Once you have that best match, you can look at the star formation history, because in simulations you have access to the entire history of the galaxy."
While JWST looks into the farthest reaches of the universe, other research is uncovering mysteries closer to home. The Italian news agency ANSA reported on August 2, 2026, about a study coordinated by the University of Bologna, with the participation of the National Institute for Astrophysics. The study analyzed nitrogen-rich stars in our Milky Way galaxy.
Ellen Leitinger, the study's first author, told ANSA: "The chemical composition suggested an origin in globular clusters." These are ancient groupings of stars that are among the oldest objects in the universe. However, many of the analyzed stars appear too young to have originated from such clusters.
Andrea Miglio, author of the study from the Department of Physics and Astronomy "Augusto Righi," explained the method: "It allows us to measure the current mass of these stars, while age is not measured directly: it is estimated by comparing mass and evolutionary state with models of individual stars." However, he warned: "If a star has had a more complex evolutionary history, this estimate can be wrong." This finding challenges existing models of stellar evolution.
