3 ms·
> therefore an average density of 5.33 to 8.38 mg/m3 That's nuts. How on earth does fusion happen at that density? Is there a denser core that actually fuses,
by margalabargala 7d ago
> therefore an average density of 5.33 to 8.38 mg/m3
That's nuts. How on earth does fusion happen at that density? Is there a denser core that actually fuses, and the outer fluffy bits just glow from the inner heat?
- adrianN 7d agoAverages are quite misleading. The core is obviously a lot denser. Our sun has an average energy output per cubic meter that is comparable to a compost heap.
- margalabargala 7d agoSure, but now I'm left wondering what the size of the body doing fusion is. If most of the star is glorified glowing atmosphere, I want to know the mass and radius of the fusing bits.
- peri-cl 7d agoThere's dedicated Wikipedia articles responsive to this, https://en.wikipedia.org/wiki/Solar_core https://en.wikipedia.org/wiki/Solar_core
- idiotsecant 7d agoDepends on the class of the star. Our sun? About 1/4 radius and in is fusion reaction. But it gets weird in other stars. In red giants the fusion zone is a very small shell around a dead core. Maybe something like earths orbit in radius, but very very thin.
- throwaway89864 7d agoAstra says this claim is misleading. Sun's average energy output per cubic meter is three orders of magnitude smaller than that of a compost heap. The fusion core is comparable though.
- Retric 7d agoThe energy density of specific compost heaps varies by several orders of magnitude it’s not a single number. Volume, moisture content, internal temperature, external temperature, materials being composted, etc all play a significant role.
- mordechai9000 7d agoStellar fusion could also be a factor in a sufficiently large compost heap.
- malfist 7d agoOf course it's misleading, thats the point GP was trying to make. Averages belie truth in large, diverse systems with extremes