JWST may have best evidence yet of strange ‘black star’: ScienceAlert

JWST could have spotted the “smoking gun” of a hypothetical object called a dark star in the distant Universe. If confirmed, this discovery could solve several mysteries of physics.

A dim star may sound like an oxymoron, but it would still emit light and energy. However, it wouldn’t be powered by nuclear fusion like a garden star – it would run on a core of interacting dark matter particles.

“Supermassive dark stars are extremely bright, giant, but puffy clouds, consisting mainly of hydrogen and helium, which are protected from gravitational collapse by the tiny amounts of self-annihilating dark matter they contain,” explains Cosmin Ilie, an astrophysicist at Colgate University in the United States.

Related: Dark matter research could lead us to a new type of star

Today, researchers have found the best evidence yet for the existence of dark stars. By studying four of the most distant objects ever observed, the team found that all were consistent with a dark star explanation.

Most intriguing, however, is that one of the objects exhibited a particular characteristic of absorbing light at the wavelength of 1,640 Angstrom. This is considered a sure sign of the presence of dark stars, which arise from the unique ionized helium present in their atmospheres.

“Although the signal-to-noise ratio of this feature is relatively low, this is the first time we have found a potential smoldering signature of a dark star. Which, in itself, is remarkable,” says Ilie.

Shortly after JWST kicked off in 2021 and began peering further into space and time than humans had ever done before, it captured some unexpected images. Near the dawn of time were what looked like huge galaxies at a time when there shouldn’t have been enough time (literally) for them to get so big.

Astrophysicists quickly found a possible explanation for some of them: the dark stars, which could contain up to a million Suns in mass, would look like galaxies at that distance.

The new study analyzes the spectrum and morphology of four of these objects. One appears to be a point source, while the other three are slightly more diffuse, meaning they could be dark stars surrounded by nebulae of ionized hydrogen and helium.

On the other hand, the researchers admit that the four objects could still be interpreted as galaxies. But that raises its own questions. Dark stars, although hypothetical, can solve several mysteries.

Not only could they provide some clues about the nature of dark matter, but their eventual disappearance would theoretically see them collapse into black holes with a huge starting mass. Supermassive black holes were discovered very early in the history of the Universe, at masses that should be impossible based on existing theories of their growth. Dark stars might give them a shortcut.

Further observations are needed to confirm the identity of these distant giants, but they appear to rewrite what we know about physics, whatever that may be.

The research was published in the journal PNAS.