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Astronomy: Astronomical objects Start‑class High‑importance

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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)

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