Are There Stars Primarily Composed of Helium?

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    Helium Stars
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Stars primarily composed of helium do exist, notably classified as "Extreme Helium Stars," which have low or absent hydrogen in their surface spectra. These stars are often remnants of evolved stars, like white dwarfs, where the outer layers consist of helium while the core remains primarily carbon and oxygen. There is a theoretical model suggesting that colliding white dwarfs could lead to a star with a higher helium composition than other elements. However, a star significantly smaller than solar mass may take an extremely long time to evolve past the hydrogen stage, potentially exceeding the current age of the universe. Thus, while rare, helium-rich stars can occur under specific conditions.
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Are there stars primarily composed of helium?
 
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There are many stars whose CORES are composed of helium -- and even stars with cores of heavier elements.

- Warren
 
Originally posted by Loren Booda
Are there stars primarily composed of helium?
There is a class designated "Extreme Helium Stars", but this comes from the spectra of the surface only where Hydrogen is low or lacking. Most would be the "remnant" (white dwarf) of an evolved star, leaving behind the outer helium burning shell as a "surface", even though the interior would still be composed mostly of carbon and oxygen.

But, there is one model where colliding white dwarfs could cause the combination of helium total to exceed the other elements. So, I guess the answer is probably yes, in rare occassion.
 
A star that was smaller

than solar mass by a factor of two or three might never get past the Hydrogen to Helium stage but that would take a long time, it would be older than the universe is now before the Hydrogen was all used up.
 
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