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CrimsonEnigma t1_j2bno8o wrote

Just to note: Alpha Centauri A is not a red dwarf; it’s actually a G2V star, just like the Sun.

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GeorgeOlduvai t1_j2c5n7f wrote

The red dwarf companion is Proxima, IIRC. Alpha Centauri A and B are yellow and orange stars, right?

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yanessa t1_j2c8j3v wrote

A (Rigil) G2V

B (Toliman) K1V

C (Proxima) M5.5Ve, both UV-Ceti and BY Draconis variable

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CrimsonEnigma t1_j2c9imt wrote

Yea, Proxima Centauri is the red dwarf. I'm not sure about Alpha Centauri B's color. Star color is weird in and of itself; while we call stars like Alpha Centauri A and the Sun "yellow dwarfs", they're actually both white - the Sun only looks yellow because the atmosphere scatters more light in the blue end of the spectrum than the red end. Were you standing on the moon and staring at the Sun, it wouldn't appear yellow at all, though staring at the Sun usually isn't a good idea.

Incidentally, Proxima Centauri has an earth-sized planet around it that's on the inner edge of the habitable zone, though probably isn't actually habitable for the reasons OP pointed out.

There is a very tentative candidate for Alpha Centauri A. If confirmed, it would be a Neptune-sized planet also in the habitable zone (though barely), though again I must emphasize that this is *extremely* tentative. These candidates pop up around stars from time to time and a lot of them turn out to just be artifacts in the data.

If it is real, though, it should be big enough, far enough away from Alpha Centauri A, and close enough to our own solar system that we might be able to observe it with the JWST.

That's a long time off, though.

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thewerdy t1_j2cj9mc wrote

Fun fact, you can see Alpha Centauri B in the night sky of Pandora in the first film. It's an unusually bright star.

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