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October 20, 2025 13 mins

Astrophysicists may have spotted evidence for “dark stars,” an unusual type of star that could possibly have existed in the earliest days of the universe, in data from the James Webb Space Telescope. Instead of being powered by nuclear fusion as current stars are, the controversial theory says that these ancient dark stars would have formed by mixing a huge cloud of hydrogen and helium with a type of self-annihilating dark matter. Dark stars would not have been dark—researchers believe that if they existed, they would actually have been bigger and brighter than current stars.

Astrophysicists Katherine Freese, who first proposed the idea of dark stars in 2007, and Cosmin Ilie, who detected the possible signs of the dark stars, join Host Ira Flatow to discuss the theory.  

Guests:
Dr. Katherine Freese is a theoretical astrophysicist and a professor of physics at the University of Texas at Austin.
Dr. Cosmin Ilie is an assistant professor of physics and astronomy at Colgate University.

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