Scientists for the previous 15 years have been searching for proof of a kind of star solely hypothesised however by no means noticed – one powered not by the fusion of atoms just like the solar and different odd stars however by mysterious stuff referred to as darkish matter.
Because of the James Webb House Telescope’s skill to see again to the daybreak of the universe, the primary good candidates to be “dark stars” have been recognized.
The three objects noticed by Webb, which was launched in 2021 and started amassing information final yr, had been initially recognized final December as a number of the universe’s earliest-known galaxies however, based on researchers, as an alternative may really be humongous darkish stars.
Darkish matter, invisible materials whose presence is understood primarily based mostly on its gravitational results at a galactic scale, could be a small however essential ingredient in darkish stars. These stars are described as made nearly totally of hydrogen and helium – the 2 components current through the universe’s infancy – with 0.1 per cent of their mass within the type of darkish matter. However self-annihilating darkish matter could be their engine.
Darkish matter is invisible to us – it doesn’t produce or straight work together with gentle – however is believed to account for about 85 per cent of the universe’s matter, with the remaining 15 per cent comprising regular matter like stars, planets, fuel, mud and Earthly stuff like pizza and folks.
Darkish stars would have the ability to obtain a mass no less than 1,000,000 occasions better than the solar and a luminosity no less than a billion occasions better, with a diameter roughly ten occasions the gap between Earth and the solar.
“They’re big puffy beasts,” mentioned Katherine Freese, a theoretical astrophysicist on the College of Texas at Austin and senior creator of the analysis revealed within the journal Proceedings of the nationwide Academy of Sciences.
“They are made of atomic matter and powered by the little bit of dark matter that’s inside them,” Freese added. In contrast to odd stars, they might have the ability to acquire mass by accumulating fuel falling into them in area.
“They can continue to accrete the surrounding gas almost indefinitely, reaching supermassive status,” mentioned Colgate College astrophysicist and examine lead creator Cosmin Ilie.
They might not have been as scorching because the universe’s first technology of odd stars. It was the nuclear fusion occurring within the cores of these stars that spawned components heavier than hydrogen and helium.
The three objects pegged as potential darkish stars date to early within the universe’s historical past – one from 330 million years after the Huge Bang occasion that bought the cosmos going 13.eight billion years in the past, and the others from 370 million years and 400 million years after the Huge Bang.
Based mostly on the Webb information, these objects may very well be both early galaxies or darkish stars, Freese mentioned. “One supermassive darkish star is as vivid as a whole galaxy, so it may very well be one or the opposite.”
Whereas there may be not sufficient information to make a definitive judgment about these three, Freese mentioned, Webb might be able to acquire fuller information on different equally primordial objects that would present “smoking gun” proof of a darkish star.
Situations within the early universe could have been conducive to formation of darkish stars, with excessive darkish matter densities on the areas of star-forming clouds of hydrogen and helium. Such situations are extremely unlikely immediately.
Freese and two colleagues first proposed the existence of darkish stars in 2008, basing the identify on the 1960s Grateful Useless track “Dark Star.”
“It would be really super exciting to find a new type of star with a new kind of heat source,” Freese mentioned. “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.”