The James Webb Space Telescope has uncovered a supermassive black hole — the BiRD (Big Red Dot) — with a mass near 100 million Suns, dating to "cosmic noon" about 4 billion years after the Big Bang. Spectral analysis shows dense, turbulent gas near the core and an energy output consistent with active growth, yet the source emits almost no X-rays or radio waves. Researchers suggest heavy obscuration or a thick, puffed-up accretion disk could explain the faint high-energy signal and plan deeper, multiwavelength observations to find more such objects.
JWST Reveals a 100-Million-Solar-Mass "Big Red Dot" — A Puzzling Black Hole from Cosmic Noon
The James Webb Space Telescope has uncovered a supermassive black hole — the BiRD (Big Red Dot) — with a mass near 100 million Suns, dating to "cosmic noon" about 4 billion years after the Big Bang. Spectral analysis shows dense, turbulent gas near the core and an energy output consistent with active growth, yet the source emits almost no X-rays or radio waves. Researchers suggest heavy obscuration or a thick, puffed-up accretion disk could explain the faint high-energy signal and plan deeper, multiwavelength observations to find more such objects.
05:03 AM, 11/21/2025Science
A team of astronomers has identified a supermassive black hole with a mass of roughly 100 million times that of the Sun using the James Webb Space Telescope's powerful infrared instruments. The object, nicknamed the BiRD (Big Red Dot), appears to date from "cosmic noon," a period about 4 billion years after the Big Bang when galaxies and black holes were growing rapidly.
The discovery was reported in Astronomy & Astrophysics (October 2025) in a paper titled "A big red dot at cosmic noon." The international team includes researchers affiliated with the Space Telescope Science Institute, the European Space Agency, Yale University and the University of Cambridge. Their analysis connects the BiRD to a larger class of faint, compact infrared sources JWST has revealed in deep surveys — the so-called "little red dots."
How the BiRD was studied
Using JWST's infrared spectra, the researchers decomposed the object's light into components produced by gas at different velocities. Broad emission from fast-moving gas close to the black hole and narrower features from more distant gas were examined, along with absorption lines. The spectra indicate extremely dense, turbulent material near the central engine, consistent with active accretion.
Why the BiRD is puzzling
Although the BiRD's inferred luminosity and spectral signatures match expectations for a growing black hole of ~100 million solar masses, it is unusually faint in X-ray and radio observations — archival or follow-up data show almost no detectable high-energy emission. That discrepancy is unexpected because accreting supermassive black holes typically produce X-rays from the innermost regions and radio emission from jets or coronae.
Leading explanations proposed by the authors include:
- Heavy obscuration: an optically thick, possibly Compton-thick cloud of gas and dust could be hiding X-rays from view.
- Geometrically thick accretion: rapid, possibly super-Eddington accretion could produce a puffed-up disk that either blocks or cools the X-ray–emitting region.
Next steps
The team plans deeper, multiwavelength observations — including more sensitive X-ray and radio follow-up — and wider surveys to find additional examples. Discovering more BiRD-like objects at different distances will reveal whether these sources are rare curiosities or a previously overlooked population that played a role in black hole and galaxy growth during cosmic noon.
Understanding the BiRD could refine models of black hole accretion and obscuration and offer insight into how the supermassive black holes we see today grew in the early universe. There is no danger to the solar system from this distant object.