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|WikiProject Astronomy||(Rated B-class, Top-importance)|
|WikiProject Physics||(Rated B-class, Mid-importance)|
- 1 Corrected a statement
- 2 Biggest star that can form today
- 3 Merger from Stellar population
- 4 Population 0 stars
- 5 More needed
- 6 article missed out a candidate Pop III HII galaxy.
- 7 Contradiction
- 8 Deblippification
- 9 Units of metallicity
- 10 How do they get these figures?
- 11 How could Population III stars create the first 26 elements if they contained no metals?
- 12 Pop III - Link Dump
- 13 Population III stars and Pair-Instability Supernovae
- 14 Metallicity of Galaxies and the Interstellar / Intergalactic Medium?
- 15 Pop III star?
- 16 What metallicities for pop 1 and pop 2
- 17 Relation between Z and [M/H]
- 18 Bolding
Corrected a statement
"regular chemistry has almost no relevance in astrophysics. This is patently false - I believe it was meant to read "regular chemistry has not relevance in a discussion of stellar interiors. I changed it as such. —Preceding unsigned comment added by 18.104.22.168 (talk) 23:12, 1 May 2008 (UTC)
Biggest star that can form today
"The most massive star that can form today is about 110 solar masses with a possible extreme maximum upper limit of 150 solar masses" i.e. "The maximum mass for a star today is 110 solar masses, with a maximum mass of 150 solar masses". Which is it? 110 or 150? Or is it that 110 is the largest mass that a star can start with, and 150 is the largest mass that a star can have and still be stable after accretion etc? AstroDave (talk) 10:50, 14 April 2008 (UTC)
Merger from Stellar population
I see that Stellar population has been merged into this article. This seems a bit odd to me - while metalicity is a big part of the population classes, the population classes also have other aspects with stellar and galaxy formation, and as such I think that they deserve to be in their own article. Mike Peel 18:16, 22 November 2006 (UTC)
- Perhaps that is the case, but there was nothing in that article that was not in the reconstituted Metallicity article. If there are other factors which inlfluence stellar classification, then perhaps they could be added to a newer version of the article, but the article, as written, was only a shorter version of this one. Serendipodous 18:51, 22 November 2006 (UTC)
- Fair enough. I'd like to see them split back at some point, but for now I guess they're OK being combined. Mike Peel 19:27, 22 November 2006 (UTC)
Population 0 stars
Population 0 stars redirects here but I can't find any information about them in any of the five articles I combined to create this one, nor can I find any information on them in Google or Google Scholar. I even went back and checked every past edit in Stellar population, to which the redirect linked originally, but found no mention of them. Does anyone know what they are? Serendipodous 16:59, 25 November 2006 (UTC)
- Never heard of it – maybe confused by luminosity class 0?? As much as I can understand, they represent a far future luminosity class. Rursus 17:29, 8 January 2007 (UTC)
- Now the really bad qualities of Wikipedia occurs – there really are hits on "population 0 stars". All of them obviously being information copied from wikipedia! No real information, but as soon as desinformation occurs on wikipeda, it propagates over Internet. This is neither a conventional responsibility issue, nor a honesty issue - this is a mathematical complexity issue: imagine a situation when desinformation overweights the true information (YES, there is a truth, and there is an objectivity – otherwise my involvement here is meaningless) then desinformation will propagate over internet despite being removed from wikipedia, if desinformation propagates more than true information, the meaning of Internet will be truly destroyed. (Conclusion: I will delete "population 0 stars". Rursus 19:12, 8 January 2007 (UTC)
- As another explanation, perhaps someone confused the term with a class 0 protostar? Sadly, I see that there's no reference of classes on the protostar page, so I guess that's something else to go on the to do list... Spiral Wave 17:26, 27 January 2007 (UTC)
- Uh, turns out the class descriptions are tucked away in the Herbig-Haro objects article. Seems to me a short description should go in the protostars article too - a more 'obvious' place to look - but duplicating material seems a waste (and it's too good to remove from the featured article). Unless anyone has any thoughts, I'll just leave it then... Spiral Wave 00:02, 28 January 2007 (UTC)
- Forgive me if I'm being dense, but, by extrapolation, wouldn't population zero stars be super-metallic stars that will form when the population I stars start dying and blasting their materials into space? I was actually looking for information on such occurrences in this article and was curious about it's lack. Is this because nobody's done an extrapolation of what the next generation of stars will look like (unlikely) or because there is a reason to think such a generation will not happen (which should probably be mentioned). --Suttkus (talk) 03:00, 26 March 2009 (UTC)
Ordinary school books (university level) tells us more – mostly about subpopulations betw popI and popII. More is also needed for my carbon stars extras to make sense. L8R Rursus 17:27, 8 January 2007 (UTC)
- Done (L8R) Rursus 00:27, 9 January 2007 (UTC)
article missed out a candidate Pop III HII galaxy.
Might I comment that the article has left out the possible detection of a Pop III starburst at z~3.
http://news.bbc.co.uk/2/hi/science/nature/3227221.stm (the BBC's summary of the work).
As Fosbury et al. (2003 ApJ 596 797) explain, the spectrum of this HII galaxy are difficult to explain in terms of photoionization by a 'normal' starburst - very hot stars (~80,000 K) seem to be required. 22.214.171.124 00:02, 18 January 2007 (UTC)
- Then include it. This is Wikipedia. Serendipodous 11:13, 18 January 2007 (UTC)
- The article is intriguing indeed, but it does not mentions population III, it mentions that a Lynx arc is a structure with early super-luminous stars nearest to what we believe the "earliest stars" to be – we believe that means pop III, but that's not what's observed in the Lynx arc. The article is vaguely relevant – but maybe not enough so ??? Rursus 22:08, 28 January 2007 (UTC)
- I'm inclined to agree with Rursus - the article is 3 years old, if there was any further suspicion here I expect we'd have heard of it by now. If anyone knows of any such newer research on this nursery, that might well be worthy, but I think this by itself is too vague. We'll probably have to wait until the James Webb is launched before we get any real observations. Spiral Wave 00:06, 29 January 2007 (UTC)
The intro says Pop I was created first, then Pop II, then Pop III, to which the sun belongs. Later the text says the sun is Pop I, and the oldest are Pop. III. I don't know which is right, just that they contradict. UnitedStatesian 03:09, 31 March 2007 (UTC)
- Thank you, I have fixed this. (Pop III stars came first.) Spiral Wave 07:37, 31 March 2007 (UTC)
I removed lot's of ":s and some ":s. F.ex. "Big Bang" is replaced with Big Bang because it's an established term. "Heavy" is not "heavy" but in real life heavy. When highlighting a newly introduced term I use to use gizmo (bold), at other emphasis I prefer italic is a necessity. Blips should be preferred when citing in running text, or just using a simile, like: he "exploded" from rage (not me, not now, be calm!) Rursus 17:07, 1 April 2007 (UTC)
Units of metallicity
I keep running across the unit of "dex" for metallicity, which seems to be for [Fe/H]. However, I haven't seen an explanation/derivative of this, and am having a fair few problems finding one. Does anyone know more about this, and if so could they post it either here or on the article, please? Thanks Mike Peel 07:42, 19 April 2007 (UTC)
- It's one of those irritating things that it's always assumed you already know about. As such, I don't know of any papers explaining it; but this Caltech page explains the units, and this page from North Carolina explains the etymology: it's a (now-deprecated) contraction of decimal exponent. Spiral Wave 17:23, 20 April 2007 (UTC)
- Worse, stars that have Metallicity in their infoboxes do not appear to use any standard. I see various units in play with no real consensus. ex Sun, 36 Ophiuchi, Tau Ceti. Is there a preferred system or unit to use? Either log10 or "% Sun" or something different? --Robert Keiden (talk) 07:06, 11 July 2012 (UTC)
How do they get these figures?
"The number of iron and hydrogen atoms per unit of volume respectively" are stated as requirements for the metallicity equation yet the entry makes no mention of how these measures are actually detected (for our own star and others). MatthewKarlsen 17:53, 25 May 2007 (UTC)
- I believe that with a Spectrometer —Preceding unsigned comment added by 126.96.36.199 (talk) 20:44, 1 January 2008 (UTC)
How could Population III stars create the first 26 elements if they contained no metals?
About half of the first 26 elements are metals, so how could they create these metals via nuclear fusion without containing them? —Preceding unsigned comment added by 188.8.131.52 (talk) 08:44, 7 March 2008 (UTC)
After the elements were fused within the star, the star then contained metals. But the terms metal-rich or metal-poor (or metal-less) generally refer to stars early in their lives when they are fusing Hydrogen to Helium and the heavy metals that were left over from previous stars can be identified. 184.108.40.206 (talk) 03:51, 12 March 2008 (UTC)
Pop III - Link Dump
Don't know what to do about this relevant link. I'm not sure whether it's a secondary or tertiary source, but it's good, because it deals with the physics explaining why Pop III is a good hypothesis. Said: Rursus ☻ 07:53, 4 August 2008 (UTC)
- Thinking a little, maybe Pop III should have a separate article dealing with this Universe astrophysics stuff. L8R. Said: Rursus ☻ 07:59, 4 August 2008 (UTC)
Population III stars and Pair-Instability Supernovae
Metallicity of Galaxies and the Interstellar / Intergalactic Medium?
The article currently focusses upon the metallicity of individual stars. The comparative metallicity of different kinds of galaxies and the distribution of metals in the interstellar and intergalactic medium are well-researched matters that should also be included. — Preceding unsigned comment added by 220.127.116.11 (talk) 16:18, 22 January 2012 (UTC)
Pop III star?
The article cites that no Pop III star is known. In 2011, Herschel telescope found SDSS J102915+172927, which has no more than 0.00007% metals and is probably more than 13 billion years old. For me this indeed looks like a Pop III star, or at least it is a nice candidate. 18.104.22.168 (talk) 12:12, 14 July 2012 (UTC)
- J102915+172927 is (apparently) very old, and very primitive, but the problem is- it's way too small. In all the sources I've found, Pop III are expected to have been massive and short-lived. I'd agree this star is something like a candidate, but it needs a better citation, otherwise OR to me. :) --Robert Keiden (talk) 08:28, 15 July 2012 (UTC)
What metallicities for pop 1 and pop 2
- We should add a reference for that claim ([Fe/H]<-6), I'll add a 'citation needed' tag. If anybody has a proper reference please add it. Cheers. Gaba p (talk) 10:21, 6 November 2012 (UTC)
- Pop 1 and Pop 2 are distinguished by a combination of metal content and stellar kinematics. The metallicity ranges overlap; there are clear Pop 1 stars with metallicities as low as [Fe/H] ~= -1.1 or so, while there are stars with Pop 2 kinematics as metal-rich as -1 to -0.5. In principle age also should be in there as well, but determining ages for stars is much harder than either space velocity or metal abundance. Mind you, with the clear knowledge that the Galaxy has consumed dwarf galaxies and their stellar content over its history, there are stars whose origins lie outside the framework that gives rise to the Pop 1/Pop 2 distinction. Finding a concise reference that says all that won't be easy, but I'll keep it in mind and hopefully find one. BSVulturis (talk) 20:19, 16 April 2013 (UTC)
Relation between Z and [M/H]
I corrected the formuli for [M/H] -- they previously stated that it was simply log(Z/Z_sun), which ignores the fact that it is the ratio of metals to Hydrogen, and the amount of Hydrogen varies between stars.
- Hi Trefusius, I tried coming up with a suitable source for that equation but the only thing I could find was this article where the formula is stated as (see eq. 9):
- log(Z) = log(X/Xo) + log(Zo) + [Fe/H]
- which would mean that the correct relation between Z and [Fe/H] is:
- log(Z*Xo/Zo*X) = [Fe/H]
- Where did you get the relation that you edited into the article? It'd be great if we could find a source like an astronomy book expressing this relation. Regards. Gaba (talk) 20:48, 30 June 2013 (UTC)
On first look, I agree with the removal of bolding done today. However, the article has quite some incoming redirects, which one could justify to bold. I'm not sure what exactly would be the best style here, but it feels like bolding the most comon redirects would be good. But only the first occurence after the redirect target, not later mentions (some of which are bolded now). — HHHIPPO 17:28, 26 August 2013 (UTC)