Alex McColgan

They bounce repeatedly through the thick gas envelope.

With every collision, their wavelengths shift slightly.

The cumulative effect produces emission lines that appear broader than they should be, leading scientists to overestimate their mass.

When researchers corrected for this, the estimated black hole mass is dropped by orders of magnitude, bringing them more in line with the expected 0.1% galaxy mass we see in our cosmic neighbourhood.

Black hole stars sound like something out of science fiction, but they elegantly solve the biggest hurdles we've encountered with the little red dots.

And the craziest part of all this is that they were predicted 16 years ago by theoretical astrophysicist Mitchell Begelman from the University of Colorado.

In a 2008 paper, Begelman proposed something called quasistars.

His model described a black hole forming from a stellar remnant or small seed inside a dense gas cloud.

Then, rather than the surrounding envelope dispersing, it would stay bound.

The black hole sits at the core, feeding.

while the outer envelope glows, not from nuclear fusion like a normal star, but purely from the energy of the black hole consuming gas at its centre.

From the outside, it would look like a single, enormous star, but inside, it's actually a supermassive black hole.

Hence, black hole star, or as he called it, a quasi-star.

Begelman's model predicted that a black hole in this configuration could grow at extraordinary rates, reaching thousands of solar masses in just a few million years while the envelope slowly cools.

Eventually, it hits a temperature floor of around 4000 Kelvin, and at that point, radiation pressure wins.

The envelope gets blown away.

The quasi-star phase ends, and what remains is a naked black hole.

Begelman argued

that rather than a type of object, quasi-stars could be a brief phase, early in a black hole's life, lasting only a few million years.

He even suggested that if a black hole were later to encounter another episode of extremely high gas inflow, similar conditions could theoretically arise again.