Talk:Red supergiant

FAIL

Is this article maintained by 12 year old children?

The radius of most red giants is between 200 and 800 times that of the sun, which is still enough to reach from the sun to. The red supergiant is one of the biggest stars in the univers!

Computer generated images

I just added a note to one of the images to clarify it's not a photo. Also, the next one of our Sun is quite inaccurate, as Celestia in its latest builds (1.5) that I believe this one was generated with now use possibly untweaked halo effects to simulate brightness not possible to achieve with a computer monitor. Our Sun would not have nearly that great of a halo in the "real world", and would look just like a ordinary star, much like Betelgeuse looks from our point of view. Actually, our Sun from there would obviously be even dimmer and harder to spot than that as it's no supergiant. -- Northgrove 10:22, 9 January 2007 (UTC)

I'd personally be interested in replacing the Celestia Betelgeuse image with this one (click for QuickTime movie too) as it looks far more accurate than what is actually just a textured sphere with a halo effect, but I'm not sure about our rights for this at this point. -- Northgrove 10:43, 9 January 2007 (UTC)

Since the Celestia images provide a misleading comparison, I have removed them and put an actual image of a red supergiant in their place, as this article was lacking for real images. Chaos syndrome 16:25, 17 August 2007 (UTC)

Extreme pressure?

A red supergiant like Betelgeuse is ~15 times heavier than the Sun and many hundred times larger in diameter. Its average density thus is ten thousand times less than than of the air we breathe. So where does "the extreme pressure in a red supergiant" come from?

Leokor

Since the mass of a red giant is heavily concentrated towards its center, the pressures near its center are much higher than they would be if its mass were uniformly distributed. Cardamon 07:34, 15 October 2007 (UTC)

Links

Are The links for the Red SuperGiant "White SuperGiant" and the "Yellow SuperGiant" that is not blue suppose to be an active link?

VY Canis Majoris

VY CMa is a K-type HYPERGIANT not an M-type SUPERGIANT. —Preceding unsigned comment added by 24.150.46.251 (talk) 00:16, 8 December 2009 (UTC)

missing

This article is missing a clear characterization of red supergiants versus mere red giants. 22:35, 30 January 2006 (UTC)

This comment is old, but I think still valid. I'm trying to formulate a simple answer, but there is certainly some qualitative difference. All the textbooks I know seem to point to red supergiants forming from those stars that ignite carbon non-degenerately. That is, they don't have a "carbon flash" (like a helium flash, but with carbon). It's hard to disentangle why this leads to a supergiant though, because that seems to classify a star based on something that hasn't happened yet.

I think the real theoretical distinction is because red supergiants are sufficiently massive that they ignite helium in the core while they are crossing the Hertzsprung gap. This happens around 8 solar masses, it seems. That means there isn't really any ascension up the giant branch. When I've ironed this out in my own head, I'll add it to the article. Warrickball (talk) 08:56, 24 June 2011 (UTC)

Copyright problem removed

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V354 Cephei

Why is V354 Cephei considered an example of a star over 1000 R_☉? It's only 690 R_☉. JayKayXD (talk) 03:21, 11 May 2019 (UTC)

Range is 689 and 1,520 solar radii according to the article V354 Cephei. I has been likely been averaged to around 1000. 08:13, 11 May 2019 (UTC)

Mass

What is the mass limit of a red supergiant? I've found an article which shows an extremely massive red supergiant (65 solar masses)! Also, what is the definition of a red hypergiant? I don't seem the difference between a red supergiant and hypergiant.

Please clarify this,

PNSMurthy (talk) 01:37, 26 July 2020 (UTC)

Move discussion in progress

There is a move discussion in progress on Talk:Supergiant star which affects this page. Please participate on that page and not in this talk page section. Thank you. —RMCD bot 03:33, 29 July 2021 (UTC)

Upper limit of red supergiants in size

We all know it's claimed there's an upper limit for stellar radii. Though however it's only a theory and such stellar models are based on the theories. There's only so much to learn and so much more ahead. New discoveries can change everything we know and history. Given how little we know about the universe, we're still only at the beginning of discovering what's out there. Stellar radii could exceed the limits and some stars are currently estimated to exceed the Hayashi limit, but estimates are based on best and most reliable calculations and as technology improves over the coming years and decades, we can only find out and calculate how large or small stars outside our solar system really are.

"Red hypergiant" listed at Redirects for discussion

The redirect Red hypergiant has been listed at redirects for discussion to determine whether its use and function meets the redirect guidelines. Readers of this page are welcome to comment on this redirect at Wikipedia:Redirects for discussion/Log/2023 April 19 § Red hypergiant until a consensus is reached. InterstellarGamer12321 (talk | contribs) 17:12, 19 April 2023 (UTC)