A possible primordial black hole that was likely born in the first microseconds of the universe, so immense that it may change our understanding of these cosmic maws, was discovered in James Webb Space Telescope data, capturing faint objects called Little Red Dots.
Renowned astrophysicist Stephen Hawking first proposed the primordial black hole concept back in the 1970s, a type of black hole that could only be formed by the extreme heat and density found in the first second following the Big Bang. Now, University of Cambridge astrophysicist Ignas Juodžbalis has led an international team suggesting that a recently discovered black hole may be the first real-world observation of the primordial variety, in a new paper available in preprint form.
Red Origins and Primordial Black Holes
Since their initial discovery by the James Webb Space Telescope, the small, faint objects called Little Red Dots have been of particular interest to astrophysicists as likely being baby galaxies hosting growing black holes. They exist at the edge of observable space in what is known as the “Red Shift Frontier,” where light traveling immense distances from the earliest days of the cosmos becomes extremely stretched out over its journey due to the rate of universal expansion.
Acting as a glimpse back in time to much earlier periods of the universe, the wavelengths become so stretched that they are only visible in the infrared by the time they reach any human observation devices. From its vantage point in space, the James Webb Space Telescope is equipped with the Near-Infrared Spectrograph (NIRSpec), an instrument vital to observing such ancient light.
Targeting a Little Red Dot
When the International team targeted one of the Little Red Dots, QSO1, for measurement with the James Webb Space Telescope’s NIRSpec instrument, the results suggested that it was a 50 million solar mass black hole. Still in the early stages of accretion, QSO1 is pulling in gas and dust as it continues to grow.
Lacking much of a halo, the black hole is considered almost “naked,” a confusing situation to the astronomers viewing QSO1, as it flies in the face of our assumptions about black hole formation. The galaxy surrounding the black hole appears to be much smaller than would be anticipated for a hole of QSO1’s size. Typically, scientists expect black holes to form after galaxies, feeding on their gas and stars to grow, while QSO1 may be doing the opposite.
Growing Around a Primordial Black Hole
The researchers suggest that, incredibly, the black hole came first and helped the galaxy grow around it, instead of the other way around, as typically occurs, in what the researchers refer to as “black-hole primacy.” In their paper, the researchers report that a primordial black hole is one of only two explanations that align with the data: the other possibility is a direct collapse.
Direct collapse black holes are another type of black hole that has remained only a theoretical possibility, involving the collapse of raw gas clouds instead of stars. Even if the object doesn’t turn out to be a primordial black hole, the other possibility is also highly unique from anything previously observed.
Further research will be required to follow up on the unusual findings. More Little Red Dots and supermassive black hole mass measurements will help clarify the earliest black hole formations, providing evidence one way or the other for black hole primacy as a cosmic reality.
The paper, “A Direct Black Hole Mass Measurement in a Little Red Dot at the Epoch of Reionization,” is available on arXiv as of September 3, 2025.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.