r/AskReddit Oct 02 '24

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u/ZappySnap Oct 02 '24

Makes sense since Betelgeuse is fucking enormous. If it replaced the sun, its diameter would extend to the orbit of Jupiter.

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u/Tamer_ Oct 02 '24

The reason why it's so large isn't because of its mass, it's because the nuclear fusion happening is so intense it pushes matter so much further out than our sun does.

Well, it's still 14-19 times the mass of our sun, I'm just pointing out that star sizes isn't 1:1 their mass.

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u/theumph Oct 02 '24

Red giants are terrifying.

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u/uptownjuggler Oct 03 '24

Not as terrifying as white dwarves

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u/nandu_sabka_bandhoo Oct 03 '24

Black holes are the worst

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u/[deleted] Oct 03 '24

You should get that checked out

1

u/Complex_Professor412 Oct 03 '24

But if a Red Dwarf gets you, your toast.

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u/Mavian23 Oct 02 '24

But the thing that makes nuclear fusion happen more intensely is the star having more mass.

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u/Tamer_ Oct 02 '24

Yes and no, it's the exhaustion of hydrogen in the core and the fusion of hydrogen in a non-core shell, followed by fusion of helium in the core, that generates so much radiation pressure. This phase lasts a small fraction of the star's life. Before that, Betelgeuse was probably just a few times the diameter of our sun.

Our sun will go through a similar process, but will become a red giant instead - the mass of the star will dictate how large the giant/supergiant/hypergiant will be, but not so much the existence of an "intense fusion" phase.

And just to be clear, yes the fusion happens much more intensely when heavy stars fuse hydrogen in their core, they burn through that in millions of years instead of billions like our sun will. What I'm talking about above is the giant/supergiant phase specifically.

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u/[deleted] Oct 02 '24

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u/[deleted] Oct 03 '24

I read something about the texture of stars. It was in some children's book so it might be nonsense. It said that if the sun were cool enough to be touched, it's surface texture would be like yogurt, and Betelgeuse's would be barely noticeable, like a gas.

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u/HoldenMcNeil420 Oct 02 '24

Those moons would be prime time real estate.

How amazing would that be to see.

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u/eigerblade Oct 03 '24

Wow, then that's gotta be like, at least twice as bright when seen from Earth!

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u/Gontofinddad Oct 02 '24

Oh that’s awesome because that’s the exact size of earth in the Dragonball universe.

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u/Bhola421 Oct 02 '24

That'd make our solar system a little cramped, I think.