James Webb telescope finds evidence of dark stars from dawn of universe

Scientists for the past 15 years have been looking for evidence of a type of star only hypothesized but never observed - one powered not by the fusion of atoms like the sun and other ordinary stars but by mysterious stuff called 'dark matter', a recent study said.

The James Webb Space Telescope, launched in 2021 and collecting data since last year, has now identified the first potential candidates to be "dark stars." These objects were initially thought to be some of the earliest-known galaxies but may actually be enormous dark stars.

"Dark matter, invisible material whose presence is known mainly based on its gravitational effects at a galactic scale, would be a small but crucial ingredient in dark stars," explained a researcher. These stars are primarily composed of hydrogen and helium, the elements present during the universe's infancy, with about 0.1% of their mass attributed to dark matter. However, it is the self-annihilating dark matter that would serve as their energy source.

"Dark matter is invisible to us - it does not produce or directly interact with light - but is thought to account for about 85% of the universe's matter, with the remaining 15% comprising normal matter like stars, planets, gas, dust, and Earthly stuff like pizza and people," added the researcher.

Dark stars would possess a mass at least a million times greater than the sun and emit a luminosity at least a billion times brighter, with a diameter roughly ten times the distance between Earth and the sun.

"They're big puffy beasts," described a theoretical astrophysicist involved in the study. "They are made of atomic matter and powered by the little bit of dark matter that's inside them."

Unlike ordinary stars, dark stars have the ability to accumulate gas falling into them in space, allowing them to continuously gain mass and potentially reach supermassive sizes.

"They can continue to accrete the surrounding gas almost indefinitely, reaching supermassive status," explained a lead author of the study.

Dark stars would differ from the universe's first generation of ordinary stars, as they would not have been as hot. The fusion taking place in the cores of those stars was responsible for the creation of elements heavier than hydrogen and helium.

The three objects initially identified as early galaxies but now considered potential dark stars date back to the early stages of the universe, ranging from 330 million to 400 million years after the Big Bang.

Based on the data collected by the Webb telescope, these objects could either be early galaxies or dark stars, leaving researchers uncertain about their nature.

"One supermassive dark star is as bright as an entire galaxy, so it could be one or the other," added the researchers.

While more data is needed to definitively classify these three objects, the Webb telescope may provide further evidence of dark stars by studying similar primordial objects.

Conditions in the early universe might have been favorable for the formation of dark stars, with high concentrations of dark matter in star-forming clouds of hydrogen and helium. However, such conditions are highly improbable in the present universe.

"It would be really super exciting to find a new type of star with a new kind of heat source," expressed the theoretical astrophysicist. "It might lead to the first dark matter particles being detected. And then you can learn about the properties of dark matter particles by studying a variety of dark stars of different masses."