What primarily supports the core of a massive Red Supergiant during helium, carbon, and subsequent burning stages?

Answer

Thermal gas pressure

Due to their greater gravitational compression, the cores of Red Supergiants remain hot enough that they are supported primarily by thermal gas pressure during subsequent fusion stages, allowing for self-regulation.

What primarily supports the core of a massive Red Supergiant during helium, carbon, and subsequent burning stages?

#Videos

How Do Red Giants Become Supernovae? - Physics Frontier

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