James Webb Space Telescope 'black hole star' may help explain mysterious little red dots in space

Since the James Webb Space Telescope (JWST) began peering deep into the early universe, astronomers have repeatedly encountered a puzzle: tiny, bright red objects that do not fit neatly into familiar categories of stars, galaxies or black holes.

Now, one particularly extreme "little red dot" may offer a clue to what some of them really are.

The object, named MoM-BH*-1, dates back to about 660 million years after the Big Bang, according to a study published in Nature. Roughly the size of the solar system, it appears almost entirely red and produces far more energy than an ordinary star could generate through nuclear fusion.

Researchers believe the most likely explanation is a rapidly growing black hole buried inside an extremely dense cocoon of gas.

In other words, the red dot and the proposed "black hole star" are the same object seen in two different ways. MoM-BH*-1 is the red point detected by the JWST, while the "black hole star" is what researchers think may be hidden inside it.

The black hole provides the enormous energy, while the surrounding hydrogen gas absorbs and reshapes the light escaping from the system, giving it some characteristics normally associated with a star. Despite the name, it is not a conventional star.

That model could help explain the many other "little red dots" the JWST has found in the early universe. Astronomers have struggled to determine what these compact red sources are. If MoM-BH*-1 is representative, at least some of them could be young black holes hidden inside dense gas and caught during an early stage of rapid growth.

That possibility could also help answer a much bigger question: how supermassive black holes appeared so soon after the Big Bang. Astronomers have found enormous black holes when the universe was only hundreds of millions of years old, leaving relatively little time for them to form and grow.

Rohan Naidu of the Massachusetts Institute of Technology, who led the study, suspects black hole stars could be an early stage in the evolution of today's supermassive black holes, including the one at the center of the Milky Way.

"For decades we have anticipated something spectacular must be afoot in the very early universe. Black hole stars may be the 'something spectacular.' They may be the nascent, swaddled phase that marks the beginning of almost every supermassive black hole's journey," Naidu said.

Supermassive black holes are found at the centers of most large galaxies and are thought to play an important role in how galaxies evolve, including influencing when stars form and when that process slows or stops.

If the black hole star model holds up, objects such as MoM-BH*-1 may give astronomers a glimpse of these enormous black holes in their infancy – still wrapped in dense gas, long before they became the giants seen at the centers of galaxies today.