The universe’s first stars may have been bloated behemoths powered by dark matter, suggests an intriguing, if speculative, new study. These ‘dark stars’ might have delayed the creation of heavy elements, which make up everything from planets to people, as well as cosmic reionisation, which made the universe transparent to light billions of years ago. Theorists believe the first stars formed in cradles of dark matter, condensing from clouds of gas until their cores became so dense that nuclear fusion ignited, preventing the cores from collapsing further. This could heat up the cloud so much that it would stop contracting, so that it was supported by the annihilation of dark matter rather than by nuclear fusion, like normal stars. Such a ‘dark star’ would be about as massive as the Sun and would glow at infrared wavelengths. But it would be much larger – depending on the mass of the neutralino used, the star could span anywhere from the distance between the Sun and Uranus in our solar system to nearly 60 times that size.
Universe’s first stars may have been ‘dark stars’