Astronomers using the James Webb Space Telescope (JWST) have identified a new type of astronomical object—dubbed a 'black hole star'—that combines characteristics of both stars and black holes. The object, designated MoM-BH-1*, is approximately the size of the solar system and emits 100 billion times more energy than any known star.
The discovery, published in the journal Nature, provides a potential explanation for the 'little red dots' (LRDs)—mysterious red specks observed in JWST images of the early universe. These dots, detected between 650 million and 1.6 billion years after the Big Bang, have puzzled scientists due to their unusual brightness and color.
Key findings from the study:
- The object’s light originates from 660 million years after the Big Bang, having traveled over 13 billion years to reach Earth.
- Unlike typical stars, which generate energy through nuclear fusion, MoM-BH*-1 is powered by a central black hole with an estimated mass 100,000 times that of the Sun.
- The object’s extreme luminosity is produced as the black hole’s gravitational forces heat surrounding hydrogen and helium gas, creating a dense, glowing cocoon.
How the discovery unfolded
Researchers initially sought to investigate bright early galaxies detected by JWST. While analyzing data from the 'Miracle or Mirage' survey, they encountered an object unlike any previously documented. The team, led by Dr. Rohan Naidu of the University of Hawaii, conducted simulations to model the object’s properties, ultimately concluding that a black hole-powered gas cloud best explained the observed signals.
The mystery of 'little red dots'
Since JWST’s launch in 2022, astronomers have observed numerous 'little red dots' in the early universe, sparking debate over their nature. Some theories suggested they were dust-obscured galaxies, while others proposed they were supermassive black holes. The discovery of MoM-BH*-1 offers a third possibility: a hybrid object where a black hole’s energy output mimics a star-like appearance.
Next steps for research
The team plans to continue studying MoM-BH*-1 and other LRDs to determine how common such objects are. Dr. Naidu noted that the findings could reshape understanding of early-universe formation, as black hole stars may represent a previously unrecognized phase in cosmic evolution.
Technical details
- Observation method: JWST’s Near-Infrared Spectrograph (NIRSpec) and Mid-Infrared Instrument (MIRI) were used to analyze the object’s light spectrum.
- Energy source: The black hole’s accretion disk emits intense radiation, heating the surrounding gas to millions of degrees.
- Size comparison: The object’s diameter is roughly equivalent to the orbit of Neptune, making it one of the largest individual objects detected in the early universe.