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Timescales
This article would benefit from having more information about timescales. For instance, how long is the interval from RGB to AGB.129.21.55.82 (talk) 19:11, 30 January 2009 (UTC)
"as large as one astronomical unit"
Probably meant to say "in radius", but the naïve might assume "in diameter." This is vague at best and wrong at worst, since isn't even Sol expected to get bigger than 1AU radius in several billion years? --Polymath69 13:33, 17 August 2007 (UTC)
"surficide reactions"? - wouldn't surface chemical reactions be better? As it is, it sounds like your talking about the results of murdering surfers. 144.137.116.114 (talk) 07:23, 17 May 2008 (UTC)Jim Jacobs.
- Nah. Point break on Rocheworld. Be there or B ;) Wnt (talk) 23:22, 6 July 2008 (UTC)
Apparent contradiction
The diagram in this article shows stars moving horizontally from the main sequence to supergiant status. The diagram shown in most of the other articles, e.g. giant star, shows the supergiants far higher in absolute magnitude. Please reconcile or clarify this. Wnt (talk) 05:21, 30 June 2008 (UTC)
- The supergiants are in roughly the same position in both diagrams. In Image:Stellar evolutionary tracks-en.svg, the luminosity of the 15 solar-mass track is shown as approximately 3·10 solar luminosities. In Image:HR-diag-no-text-2.svg, the absolute magnitude of luminosity class Ia is shown as around −7. Since 4.83 − 5 log100 (3·10) = −6.36, you can see that the positioning is approximately the same. Spacepotato (talk) 17:37, 6 July 2008 (UTC)
- You're right - the distinction is actually that the stars starting these horizontal paths are 30,000 K or hotter class O stars, which are extremely rare. The main sequence in the second link or at stops at class B and doesn't include class O. Wnt (talk) 23:17, 6 July 2008 (UTC)
- Hmm, thinking for a while about it: I think it's confusing that the image in Giant star and the image of this article regards different evolutional states of the stars. The image in this article draws a line along Zero Age Main Sequence, since the article is about star evolution; non-evolutionary HR-diagrams use to draw a line along main sequence which is some kind of mean evolutionary position. For most of the main seq the distance to ZAMS is small and constant, but becomes increasingly large for very massive stars, making ordinary HR-diagrams have kind of an upwards curve, which gives the impression of steeper increase of luminosity for "early" MS stars. Said: Rursus (☻) 14:16, 17 September 2008 (UTC)
Merge
I've just merged the stub article Asymptotic giant branch star into this article, and left a redirect there. Wdfarmer (talk) 09:23, 14 August 2008 (UTC)
Yech!
Text says:
- AGB CSE
I say: ATOTLAS! (All these obnoxious three letter abbreviation stinks). IAU should imitate the nomenclature style of IUPAC. Said: Rursus (☻) 13:26, 17 September 2008 (UTC)
Circumstellar envelopes of AGB stars - units
In the "Circumstellar envelopes of AGB stars" section there is a calculation that starts from 10 km/s and ends in 10 cm. I see no reason to have the figure as 10 cm rather than 10 m, 10 km or even 100 Pm (Peta-meters). I would like to change this, but I don't know if there is some reason cm is used. If anyone out there has an objection to changing it to 10 m, especially someone with an astronomy background, please let me know. Otherwise, I plan to change this before the month is out. Lon of Oakdale (talk) 22:29, 3 October 2008 (UTC)
LAGB?
How does LAGB phase of Protoplanetary nebula relate to TP-AGB? Equal or LAGB later than TP-AGB? ... said: Rursus (bork²) 14:30, 9 January 2009 (UTC)
There's a note at the end of the PPN article which says that they are defining the LAGB stage to be the point at which the AGB star ceases to be visible in the optical. Not many AGB people use that term (LAGB), but with that definition, the LAGB would be a subset of the TP-AGB, towards the end.Nucleardave (talk) 21:51, 7 December 2010 (UTC)
Evolutionary track image
Not sure if this is the right page for discussion, but this is one of only a couple pages that use the image http://en.wikipedia.org/File:Stellar_evolutionary_tracks-en.svg . It only shows four tracks, which could be a LOT more informative--The tracks are all extremely different, and it's hard to tell what's going on in between them! For example, what will become of a 5 Solar mass star? Will a 1 Solar mass star make the same jog to the left as a 2 Solar mass star? I've been building an understanding from this page and its image, but that deals with stars entering the main sequence, not leaving it... however, even a few more 'topographical' lines make it a lot clearer.
Can someone give an idea of where the lines for 30, 5 and 1 solar mass stars would go? Even if you can't update the image, I would like to know what they would look like. Thanks! --Sowelu (talk) 09:55, 21 October 2009 (UTC)
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