Re: Convection inside a star

On 25 apr, 00:53, will...@xxxxxxxxxxxxxxx (Steve Willner) wrote:
In article <b80f3645-6a91-493f-87ae-bf685885f...@xxxxxxxxxxxxxxxxxxxxxxxxxxx>,
Andrew Usher <k_over_hb...@xxxxxxxxx> writes:

Degeneracy pressure, right?

Perhaps you are thinking of the stability of the entire star.
Degenerate cores are stable if their mass is below the "Chandrasekhar
limit" (about 1.4 solar masses) and unstable if more massive than
that. Stars supported entirely by radiation pressure (as very hot,
massive stars are) are also unstable.

Convective stability is a question of how energy is transferred in
each layer.

For a star to be convective all the way down, I believe it must
have a source of support other than ideal gas pressure or it would
be unstable.

Nope. Red dwarfs are non-degenerate all the way down as long as
nuclear burning continues. So are massive stars burning hydrogen via
the carbon cycle.

Precisely how does "degenerate" matter differ from non-"degenerate"
liquid or solid?
.

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