Dark star (dark matter)
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A dark star is a theoretical type of star that may have existed early in the history of the universe before conventional stars were able to form. They would be composed mostly of normal matter, like modern stars, but a high concentration of neutralino dark matter within them would generate heat via annihilation reactions between the dark matter particles. This heat would prevent them from collapsing into the relatively compact sizes of modern stars and therefore prevent nuclear fusion among the normal matter atoms from being initiated.
Under this model, a dark star is predicted to be an enormous cloud of hydrogen and helium ranging between 4 and 2000 astronomical units in diameter and with a surface temperature low enough that the emitted radiation would be invisible to the naked eye.
It is possible that dark stars have endured to the modern era. Although they would emit no visible light they could be detectable by their emissions of gamma rays, neutrinos and antimatter and would be associated with clouds of cold molecular hydrogen gas that normally wouldn’t harbor such energetic particles.
The modern dark matter based dark star should not be confused with the earlier theoretical star of the same name, which is unrelated to this concept.
[edit] References
- Douglas Spolyar, Katherine Freese and Paolo Gondolo, "Dark matter and the first stars: a new phase of stellar evolution", Physical Review Letters, January (2008)
- Katherine Freese, Paolo Gondolo, and Douglas Spolyar "The Effect of Dark Matter on the First Stars: A New Phase of Stellar Evolution", Proceedings of First Stars III, Santa Fe, New Mexico, 16-20 July (2007).
- University of Michigan (2-Dec-2007). "Dark matter powered the first stars, physicists speculate". Press release.
- University of Utah (2-Dec-2007). "Were the first stars dark?". Press release.
- Spolyar, Douglas; Katherine Freese, Paolo Gondolo. "Dark matter in newborn universe doused earliest stars", Physical Review Letters, Reported in Physorg.com, December 03, 2007. Retrieved on 2007-12-04. News Report