Tiny Red Dots Spotted By NASA’s James Webb Telescope Could Be Black Hole Stars

Tiny red specks spotted by NASA's James Webb Space Telescope (JWST) have puzzled astronomers since 2022. These “little red dots” appear far more mature and luminous than expected at such an early time, leading some to dub them “universe breakers”. A new study offers an alternative: the dots might be single enormous spheres of gas surrounding voracious black holes – a novel kind of “black hole star”. If correct, this could explain how supermassive black holes grew so rapidly in the universe's infancy.

Recent Observations

According to the research in the journal Astronomy & Astrophysics, a research group under the direction of astrophysicist Joel Leja investigated these dots in 2024 using JWST's spectrographs. They gathered spectra from roughly 4,500 far-off galaxies over the course of 60 hours. One item, known as "The Cliff," stood out. Its spectrum suggested that the light originated from a single massive source rather than a group of stars, and it was located about 12 billion light-years away. Subsequent investigation revealed that the Cliff's light was consistent with that of a supermassive black hole that is covered in a cloud of hydrogen and feeds on gas.

Emerging Debates

Each dot is effectively a single giant, cold gas "star" driven by a voracious black hole, according to the black-hole-star model. Rather than a swarm of stars, Leja characterises it as "one gigantic, very cold star." However, this notion is still hypothetical. Different explanations are preferred by other astronomers. Pacucci and Loeb, for instance, propose that the dots might just be compact infant galaxies that are forming in infrequent, slow-spinning dark-matter halos, with dust or dense stars providing the red glow. Researchers stress that additional JWST observations are required to determine the best explanation.