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AsteriaStar
Stellar process

The Helium Flash

In stars below about two solar masses, the helium core becomes so dense that it is held up by electron degeneracy pressure. When helium finally ignites, the degenerate gas cannot expand to regulate itself, so fusion runs away in a brief, violent flash — over in minutes, and hidden deep inside the star.

Across stellar astrophysics

Knowledge connections

Sources

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.