The universe conceals many mysteries, and one of the most intriguing is how stars are powered. A star is born when clouds of gas collapse and a denser region is formed. From that moment on, a new star begins to grow – but how does a dark star exist? This is a question that scientists are trying to answer with a new finding deep in interstellar space. Unlike regular stars powered by nuclear fusion, these stars would have stayed relatively cool. It shines, but it has something that NASA is unsure about, since it is invisible.

The formation process of stars remains unclear

Physicists believed that all stars followed the same fundamental rules: gravity compresses gas, fusion ignites, and light radiates outward. However, this new observation challenges that blueprint. Detected in the early images from the James Webb Space Telescope, the object radiates like a star yet behaves like something entirely different. Its energy does not seem to come from nuclear fusion—at least not in any form that scientists recognize.

This has led researchers to a controversial hypothesis: the object could be powered by dark matter. Unlike anything seen before, this so-called “dark star” might use invisible particles as its energy source, rewriting basic concepts of how stars can form and exist. Now, scientists are racing to understand whether this rogue object marks the first proof that dark matter is not just surrounding galaxies—but fueling stars themselves.

The James Webb Telescope has found something intriguing

In July 2023, researchers suggested that at least three far-off objects spotted by the James Webb Space Telescope (JWST) could be something never seen before: single, supermassive dark stars. “If you find a new kind of star, that’s huge,” said Katherine Freese, an astrophysicist at the University of Texas at Austin and one of the scientists behind the discovery.

Currently, researchers cannot confirm if these objects are dark stars or just distant galaxies filled with ordinary stars. However, their strange characteristics match what scientists expect from these stars. According to Cosmin Ilie, an astrophysicist at Colgate University, JWST has the technology needed to solve the mystery—it’s just a matter of getting more observation time. “We hope we are going to find one of these obscure stars with the Webb within its lifetime,” Ilie said.

What is a dark star?

Scientists believe the first stars in the universe formed in two possible ways. The common theory says they were “Population III” stars—huge stars powered by nuclear fusion, like those we see today. But these early stars would have contained almost no metals, since heavier elements had not yet formed after the Big Bang.

There’s another, stranger theory. In 2008, Freese and her team proposed that the first stars might not have been powered by fusion at all. Instead, they could have been powered by dark matter—the invisible substance that makes up most of the universe, yet cannot be seen or touched.

In this theory, clouds of hydrogen and helium from the early universe collapsed, just like in normal star formation. But inside these clouds, dark matter particles collided and destroyed each other, releasing energy. Most particles stayed trapped inside the cloud, heating it up and allowing a new kind of star—a dark star—to grow.

The formation process

The formation process of these strange stars would have occurred at the center of “mini haloes” — early clumps of matter that existed around 200 million years after the Big Bang. Back then, heavier elements did not exist yet. These mini haloes were made almost entirely of dark matter, creating the perfect conditions for dark stars to appear, according to Katherine Freese.