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Archive 1Archive 2Archive 3Archive 4Archive 5

Mu Cephei-1,650 SR estimate

http://stars.astro.illinois.edu/sow/garnet.html found another estimate for Mu Cephei and this website proves that it's not a typo. I'm not really saying this estimate should be Mu Cephei's given radius but I'd like it to at least be mentioned in the notes. Either is fine. JayKayXD (talk) 00:56, 26 September 2018 (UTC)

 Not done for now: I don't think it proves it's not a typo; astronomers have been able to measure its angular diameter at 0.021 seconds of arc - which astronomers is he referencing? It would probably be better to get their numbers directly. Primefac (talk) 01:30, 1 October 2018 (UTC)

Eta Carinae

The Wikipedia page of Eta Carinae uses the Gull ref but says 60 R-800 R instead of just 800 R. I can't find where the Gull ref says that Eta Carinae is 60 R but if it does say 60 R and I just wasn't looking closely enough, it should be changed to 60 R because aren't we supposed to go with the smallest estimate? JayKayXD (talk) 01:23, 11 October 2018 (UTC)

Too Many Stars

Don't you think the list would be much better if we removed a huge number of stars there especially the ones in red mainly the IRAS stars, SMC, LMC (except WOH G64 and SMC 18136)? Because the ones in red don't have a page and therefore we cannot have any basis for their sizes and information. Plus it would make it more organized as the list seems really messed up and confusing to look at. Moreover, we are putting so many estimates in a single star even without basis. For example, EV Carinae is 1168-2880. Where did that 2880 come from? Yet it was placed there. If you have objections to this, then why is it they didn't put 1420-2100 for VY Canis Majoris? Or 1050-1900 for VV Cephei A. This list isn't accurate or neat anymore. I still remember how this list used to be so organized back in 2012-2015 when NML Cygni was still one of the top three in the list. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 08:14, 30 October 2018 (UTC)

It could probably stand to be trimmed, but I think if there's a reliable(ish) source for a size then it should be included. I do agree that if the object would normally fail NASTRO it doesn't need to be linked but I think inclusion would still be acceptable. Primefac (talk) 14:04, 30 October 2018 (UTC)
Inclusion would seem to be not only acceptable, but necessary. Otherwise it is just a random list of some of the largest known stars. Without a link to an article with a radius, there would need to be explicit referencing in this article.. Lithopsian (talk) 15:48, 30 October 2018 (UTC)
There really should be explicit referencing anyway, but yes, especially for the redlinked objects. Primefac (talk) 16:03, 30 October 2018 (UTC)
The list has been the subject of many edit wars, and other rounds of edits a little short of wars, some effectively ongoing. There has been a strong tendency for some editors to hunt down the largest radius estimates anywhere in the literature and put those in the list, however obsolete or borderline-OR they might be. In the worst cases, individual values are taken from a range, or calculated from a range of other properties, ignoring equally valid (usually smaller) values. Certain stars, and particular sizes for those stars, have achieved an almost-mythical status and keep appearing. Some purely historical values are still in the list, others have multiple values, sometimes not even in the individual star articles. I'm sure much pruning could be done. Lithopsian (talk) 15:48, 30 October 2018 (UTC)
I know it would put a lot more work/effort on us, but would it be reasonable to use only tertiary sources for verification? If Professor A releases a number that is pure bunk, and no one verifies it (or better yet, they refute it) then we don't include it.
The other option I suppose would be to further subdivide the table by "accuracy of method", or some other way of showing "how good" a number really is when compared to other methods.
Basically, there's no easy way to make sure this list is a good one. Primefac (talk) 16:03, 30 October 2018 (UTC)
You're never going to find tertiary sources for half these stars, and the other half are going to be retweeting research from the last century, which is literally from the last century in terms of astrophysics. Tough to add commentary that is only ever going to be some Wikipedia editor's opinion, but then we do that anyway to some extent by picking which primary source to quote. At least there are some objective criteria for using, or not, a peer-reviewed paper. I agree the list is almost entirely meaningless (margins of error on all these stars are far higher than any differences between them, so the ones near the top are simply the ones that are most wrong), but it is a fairly popular sort of meaningless. Lithopsian (talk) 16:55, 30 October 2018 (UTC)

Image for the article

Can we put a note for the comparison image saying (July 2008, outdated) since some of the size parameters are now obsolete? I have emailed Dave Jarvis, creator of the original image, to create a new updated image. Whether he actually does it is unknown as I literally asked him an hour ago. Faren29 (talk) 00:19, 7 November 2018 (UTC)

The Confusing List

Can someone check the list if they are accurate? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 08:54, 26 August 2018 (UTC)

Oh dear. What happened here then? Lithopsian (talk) 11:25, 26 August 2018 (UTC)
@Lithopsian: And also can you remove the 1,750 R for MY Cep as it is not even in the given citation (and also move MY Cep above Saturn's orbit)? BTW, also Falwey's paper gives the radius in cm, literally 1.7×1014 cm which correspond to 2,440 R. Thanks. 88.188.215.39 (talk) 12:42, 26 August 2018 (UTC)
There is much to look at. MY Cephei (note, redirect) is a particular problem, since the given radius results are highly obsolete and dubious, but there is a lack of more modern publications. I've looked at the star before with the goal of writing an article, but there was too little reliable information. Lithopsian (talk) 13:30, 26 August 2018 (UTC)

One question. Should we remove the stars above UY Scuti or are they real results? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 02:56, 27 August 2018 (UTC)

Just look in the references? If only it were that simple! The entry (entries) for MY Cephei are both highly dubious. The first is calculated from a temperature and luminosity in two different sources, the temperature quite modern but a crude value from a mass database, and the luminosity apparently the highest that could be found and 2-3 times larger than modern estimates. The second is even larger, at least calculated from a temperature and luminosity in the same paper but still thoroughly obsolete. It almost certainly shouldn't be considered the largest known star, but the problem is that it is difficult to come up with results that could be considered more reliable and verifiable in a Wikipedia sense. IRAS 05280-6910 is potentially even more difficult. The given reference states quite clearly a radius of 1,738 R and I couldn't find a more recent or more reliable publication. That radius is based on a somewhat dubious assumed effective temperature and possibly somewhat high luminosity, but that's just my opinion. The authors make no great claims for it being the largest star and the paper just gives the radius as an aside to what they are really looking at, but the number is right there published in 2016 so hard to deny it. Both these objects, and a handful of others, have poorly-characterised effective temperatures due inconsistencies between the late M spectral types, their colour indices, and some other features of their spectra. They are losing so much mass that their surfaces are not well-defined and they display a range of features from different levels within an almost-opaque stellar wind, with any true surface effectively invisible. Picking a crude value from the spectral features shown at the top of the wind give a very low temperature and corresponding huge radius, where a deeper study might choose a higher temperature from deeper in the wind, but those sorts of studies haven't been done or authors haven't chosen to characterise that sort of radius. The table has always been somewhat meaningless without a consistent definition of what constitutes the radius of such ill-defined balls of gas, but the issue gets more and more stark every time objects like this are added. Lithopsian (talk) 13:39, 27 August 2018 (UTC)

So which star is the largest? UY Scuti or MY Cephei? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 04:25, 28 August 2018 (UTC)

Mu. Lithopsian (talk) 15:16, 28 August 2018 (UTC)


Something is also not clear. Where is the reference for the size of V354 Cephei, RSGC1-F02, and RSGC1-F01? How about HD 143183, IRAS 05280-6910, and MY Cephei? Should they even be in the list without reference for their sizes? I believe UY Scuti is still the largest star. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:42, 29 August 2018 (UTC)

Are these sizes clear? Because V354 Cephei was given a 1520 solar radii and MY Cephei was declared the largest star. Is this list clear? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:50, 1 September 2018 (UTC)

VY Canis Majoris is the largest star. Joey717 (talk) 06:57, 7 September 2018 (UTC)
@V255 Canis Majoris: Already the 1,708 R for UY Scuti it's the same problem since this value is based on a very old distance. Besides the star is probably smaller than VY CMa. For more information see https://en.wikipedia.org/wiki/Talk:Mu_Cephei#Size . ZaperaWiki44(/Contribs) 12:51, 14 December 2018 (UTC)
They're all wrong. UY Sct is one where we happen to have very good evidence of just how wrong, but it probably isn't the worst in the list. VY CMa is probably one of the more accurate ones in the list. It would be helpful to spend more time thinking about how to clearly present to readers just how arbitrary the list is instead of trying to get any particular star to the top of it. Lithopsian (talk) 15:24, 14 December 2018 (UTC)

List Update

How do you editors even get constantly updated about the sizes of the stars? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 10:31, 14 December 2018 (UTC)

WHOA! WOH G64 is seriously the largest star now?! — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 15:27, 8 January 2019 (UTC)

Well, we don't know which stars is the largest and after all the size of most red supergiants are uncertain since they vary. Also the list is not yet complete and thus some paper have published even larger radii for some stars. 88.188.215.39 (talk) 16:55, 8 January 2019 (UTC)
No, not seriously. Someone is cherry-picking again. Lithopsian (talk) 16:45, 8 January 2019 (UTC)

How about RSGC1-F01 and RSGC1-F02? Aren't those cherry picks as well? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 14:13, 15 January 2019 (UTC)

How so? Lithopsian (talk) 15:45, 15 January 2019 (UTC)

Was it supposed to be 1335 and 1398 or 1435 and 1498? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 09:05, 16 January 2019 (UTC)

I'm guessing they were typos. The actual numbers are not in any sources, they are calculated from effective temperatures and bolometric luminosities. Lithopsian (talk) 16:10, 16 January 2019 (UTC)

So what's the size then of these two stars? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 22:25, 17 January 2019 (UTC)

Table says 1435 and 1498. Looks right to me. Do you think they should be something else? Footnote might be nice explaining where the numbers come from. Lithopsian (talk) 14:21, 18 January 2019 (UTC)

So then where did they get the 1335 and 1398? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 10:53, 19 January 2019 (UTC)

http://cas.sdss.org/dr4/en/proj/advanced/hr/radius1.asp

Check this out. They have the formula to computing the radius.

We know the temperature of the Sun is 5800K. From the chart, the temperature of Sirius is about 9500K. Our Sun has an absolute magnitude of 4.83. The difference in magnitude is 3.37. Putting everything together yields

R/Rs = (5800/9500)^ 2 x (2.512 ^ 3.37)^ 1/2 = 1.76

Sirius has a radius approximately 1.76 times that of our Sun!

I made the same computation for VY Canis Majoris and it is estimated to 1938 solar radii.

VY Canis Majoris

Magnitude Difference=14.23

Temperature=3490 K

5800/3490 ^ 2 x 2.512 ^ 14.23 ^ 0.5

=1937.96012423215328

The effective temperature of the sun is defined to be 5,772 K regardless of its actual temperature, which in any case varies slightly depending where you measure it. Using absolute magnitudes to do the calculations is of course possible, but you need to use a bolometric absolute magnitude, not a visual one. Also, absolute magnitudes are often rather old, very old in this case. Older parameters for red supergiants tend to be both more luminous and cooler than newer ones, leading to very large radius values. A bolometric luminosity directly given in solar units is often newer and more reliable, in the case of VY CMa 270,000 L is given in its article. You should also be cautious about using temperatures and luminosities from different sources to do this calculation, there may be conflicting assumptions used to derive them and they can fall foul of Wikipedias synthesis rules. That's why it is doubly important to note how the number was derived. It is preferred to use a radius value actually quoted in a reliable source, even if it is a little older. Where the wrong values for F01 and F02 came from isn't clear because they aren't described or cited, but I'd guess they are just typos. I know where the newer values came from, a calculation like you did from the values in RSGC1. Lithopsian (talk) 14:47, 20 January 2019 (UTC)

Do you mean to say that all sizes here are uncertain? In this case, there is no largest star is there? Or is UY Scuti still labelled as the largest star? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 17:25, 20 January 2019 (UTC)

I don't think I said that here, but I've said it elsewhere. The uncertainties in all these values are far larger than the differences between the stars themselves. Statistically, the star placed at the top of the table at any particular time is likely to be the one that is most "wrong". In the case if UY Scuti, this seems very likely since its Gaia distance is far smaller than assumed when calculating its radius. Lithopsian (talk) 17:47, 20 January 2019 (UTC)

What's with the largest estimates? What bothers me most is Westerlund 1-26 and KY Cygni. It has been confirmed that they were just heavy dust extinctions. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 05:23, 21 January 2019 (UTC)

Are the stars' sizes still even under observation? Most stars haven't changed their sizes like VY Canis Majoris and ESPECIALLY KY Cygni. The list hasn't been changed that often anymore and it gets pretty boring. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:21, 1 April 2019 (UTC)

I didn't realize that the list needed to be dynamic. Some lists like Messier object have pretty much never changed. Primefac (talk) 14:18, 1 April 2019 (UTC)

Does nostalgia ever hit you? How most stars used to be title holders or even close to that then they drop down are easily surpassed by many other stars. No wonder there aren't much size comparisons because we all used to be surprised of how large these stars were that the Sun wasn't even a speck of dust but now, it's nothing new anymore. When a star's size never changes, there is really no point of talking about how large it is and that's pretty sad. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:14, 9 April 2019 (UTC)

Where Is V283 Carinae?

I just realized something. I have searched all over for V283 Carinae and it's nowhere to be found. Videos, pages, nowhere to be found. What happened to V283 Carinae? Does it exist? Is it still alive? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 06:13, 24 April 2019 (UTC)

No variable star numbers that low. Were you thinking of a similar, but larger, number? Lithopsian (talk) 14:15, 24 April 2019 (UTC)

Lithopsian, that star appeared in so many size comparison videos especially during the old VY Canis Majoris videos. It is like nearly the size of Betelgeuse. All I know was that it was a yellow supergiant smaller than V382 Carinae. If you know that star, what happened to it? Here's one of the videos.

https://www.youtube.com/watch?v=lyW5K01HsyY — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:51, 27 April 2019 (UTC)

Nothing happened to it. It never existed. At best it was a typo, at worst a complete fanatasy. Don't believe everything you see in YouTube videos. At a guess, someone wrote V382 as V283 at some point and nobody ever bothered to check. Lithopsian (talk) 13:09, 28 April 2019 (UTC)

I feel sad for V283 Carinae. But you know, it isn't always a typo since in some videos, V283 Carinae and V382 Carinae are both there. There are some websites like beyonduniverse.wiki where they put fake stars but they never place V283 Carinae. Even the website where they make stars into living characters, no V283 Carinae there either. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 11:27, 8 May 2019 (UTC)

V283 Car (RA 09 31 29.65 Dec. -68 07 32.8) is MU Car, an RR Lyrae variable. Not a supergiant, nothing special.
Perhaps: IW Car, V370 Car, AG Car (V61 Car), V526 Car, RT Car??
Note: RT Car (V12 Car) in open cluster Tr 15 might be a possibility. RT Car especially, as it is M2Ia-0. Arianewiki1 (talk) 04:36, 10 May 2019 (UTC)

Ok no matter what you say we have to pick a format.

some use the Mid range(VV Cephei A) some use the high range(UY Scuti) and some use the low range(KY Cygni) , what are we using? low? mid? or high? , i suggest mid range for being the safest bet.Joshoctober16 (talk) 18:50, 15 September 2019 (UTC)

Previous consensus was to use the lowest given value. The high values are problematic, not least by almost certainly being more inaccurate than the low range. The "mid" is problematic in that it tends to be an average calculated by us, ie. WP:SYNTHESIS. Incidentally, 1,400 R for VV Cep A is not a "mid", it is a "single", there is only one value in that column. There is still a big wide fuzzy area of which low and high (or single) estimates are chosen to be in the list. I wouldn't be surprised if there are entries that don't follow that convention: this article tends to attract a lot of attention, not always a lot of care. Lithopsian (talk) 19:09, 15 September 2019 (UTC)
Hm... so its generaly the lowest ... 2 things to note , UY scuti and VY cain both need to have a change , some one forgot to put the lowest estimate in the ranking for VY and for UY the new measurment of around 800 , and not even the largest star , even the mid range its not the largest star nor is for its end range , for my second question is should we add a Mid and Low range for the stars? like both on different column beside each other type? Joshoctober16 (talk) 19:22, 15 September 2019 (UTC)
Oh and to make it more awkward for UY imagen if the 825 R was not seen yet , it would still mean WOH G64 and Westerlund 1-26 are larger since the older mesurment min range is at 1516 R for UY.Joshoctober16 (talk) 19:26, 15 September 2019 (UTC)

Is This For Real?

I saw that UY Scuti isn't the largest star anymore and has shrunk to 755 solar radii. I also saw KY Cygni and HD 143183 shrunk. This isn't another random edit right? This is for real right? Have they really shrunk in size? Are all the other edits errors or are they all true? I have never been so shocked in my entire life reading the list right now. I feel sad for UY Scuti though. I will miss all the times VY Canis Majoris and UY Scuti kept competing in Youtube videos. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 07:49, 22 March 2020 (UTC)

These new sizes come from Gaia data so they might not be 100% accurate but it’s the most recent data we have for now. There might be more stars that get new sizes in the future Nussun05 (talk) 05:57, 23 March 2020 (UTC)
Absolutely. The stars haven't shrunk (or maybe they have, but not that we can tell). Just that our understanding of how big they are has changed. Mainly because our estimates of their distances has changed. Fear not, I'm sure there will be more videos about large stars. Maybe VY CMa will come back into fashion as the sizes of all the other big stars get revised. Lithopsian (talk) 15:18, 23 March 2020 (UTC)
Right now, WOH G64 is at the top of the list at 1,540 R. Some stars have sources suggesting that they're larger than 1,540 (eg. VY Cma, Mu Cep, NML Cyg) but those aren't the most recent and/or reliable estimates. That said, these sources for all of the stars on this list likely aren't 100% accurate. They're the best we have for now though. The point is there's still a lot of controversy and doubt on which is the largest known star so there isn't much point in saying it's this star or that star because we really don't know for sure.JayKayXD (talk) 00:23, 24 March 2020 (UTC)
The whole article a a bit dodgy. We are essentially making a claim - that WOH G64 is the largest known star - based on WP:SYNTHESIS, explicitly banned by Wikipedia. The radii we have chosen to take as a most reliable for the various stars mostly come from different sources, based on different types of observation, and in some cases different forms of calculation (eg. angular diameter or luminosity/temperature). The whole article is hedged with caveats, but we need to be very careful not to make statements such as "this star is the largest known" based solely on this Wikipedia article. Lithopsian (talk) 20:28, 24 March 2020 (UTC)

Messineo & Brown source might be inaccurate

The source gave values lower than 400 solar radii for VV Cephei A and AH Scorpii. Gaia data has also given values way too high for Delta Cephei (640 sr) or Iota Carinae (850 sr) or even 4700 solar radii for Mu Cephei. It’s known that gaia data can be very inaccurate for some stars like UY Scuti so maybe it should be moved up to 1708 solar radii again which was also calculated using a more accurate method. Nussun05 (talk) 11:11, 19 April 2020 (UTC)

What basis do you have for considering one source to be less accurate than another? Specifically, what do you think makes the UY Scuti data from Messineo & Brown to be less reliable than that from Arroyo-Torres et al.? Lithopsian (talk) 19:51, 20 April 2020 (UTC)

Proposal to highlight different measurement methods

Should we highlight angular diameter, eclipsing binary, and disk-emmission based estimates? They seem to be more accurate than the L/teff estimates, since a lot of outside factors can affect the star, causing them to deviate from from the calculated estimate, whereas for AD estimates, as long as we're confident that we have the distance right we know generally how big the star is, instead of relying on a calculation based on several parameters that can be subject to large errors. There are 10 stars with AD estimates above 700 Rsol (HR 5171 Aa, VY CMa, AH Sco, V602 Car, KW Sgr, GCIRS 7, Betelgeuse, RS Per, S Cep, and V838 Mon) There are 3 stars with disk emission based estimates (S Per, S Cas, and HD 179821) There are 3 special cases.... VV Cep A. The 1050 Rsol estimate is determined from observations of the eclipsing binary IIRC, but there are some AD estimates that also do agree well. Because the nature of the system in not well known, the size estimates can definitely change without warning. Mu Cep. Mu Cep has a well-determined angular diameter but not a well-determined distance. Gaia distances are extremely poor for Mu Cep - I could not find a source for the 1650 solar radii estimate. UY Sct. The current estimate is from Messineo and Brown's paper using L/Teff, but there have been AD estimates in the past. Arroyo-Torres et. al. gave an angular diameter, but the 1708 solar radii estimate was calculated using a distance value that we now know is most likely not correct. However, luckily, Gaia DR2 has a reasonably well-defined parallax for UY Sct, from which I was able to calculate a diameter of 916 +- 201 solar radii. Not sure if this is a WP:OR, since it was hand calculated from two different sources, but give the amount of estimates that were calculated using L/Teff I'm not entirely sure. Thoughts? Ardenau4 (talk) 20:28, 23 April 2020 (UTC)

We report information from reliable verifiable sources. We do not "add our own spin". This article is inevitably full of all sorts of dodginess by Wikipedia standards. Let's not make it worse. Especially lets not make dubious claims about which method is more accurate when all of them are so full of holes. Lithopsian (talk) 20:39, 23 April 2020 (UTC)
That's a good point. Ardenau4 (talk) 06:00, 24 April 2020 (UTC)

HR 5171 A

Lithopsian, please check the list again. Is it right? HR 5171 A was 1492 solar radii and IRAS 05280-6910 was 1738 solar radii. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 09:43, 23 April 2020 (UTC)

Yes, this should be correct according to the newest estimates.

Ardenau4 (talk) 20:11, 23 April 2020 (UTC)

Apparently not. Lithopsian (talk) 20:35, 23 April 2020 (UTC)

If so, please check the list and change it accordingly. I have doubts for those sizes above WOH G64. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 06:37, 24 April 2020 (UTC)

Radii for RSGC1 stars

Hi, I was wondering where the radii for the stars in RSGC1 come from. It seems like most of them come from this source - https://arxiv.org/abs/0711.4757 but it doesn't seem to have radii values anywhere. If it were calculated from, say, the temperature and luminosity, that should probably be made more clear. LukeCEL (talk) 20:51, 28 April 2020 (UTC)

The inline references in the article give that paper, the radius values in the table match those calculated from the effective temperatures and bolometric luminosities, and the column that gives the method used to derive the radius says L/Teff, so I don't think it is a stretch to say that's where they come from. Lithopsian (talk) 13:49, 29 April 2020 (UTC)
Okay. I think confusion arises because for some stars the radii are already in the paper, but for others it has to be calculated. By the way, is that original research? LukeCEL (talk) 16:37, 30 April 2020 (UTC)
It's borderline. The relation between temperature, luminosity, and radius is strict and well-defined, so that in itself isn't original research. However, things like taking a temperature from one paper and a luminosity from another fall foul of WP:SYNTHESIS; different assumptions may be made in different papers, observational methods may be different, etc. In general, getting a radius number actually provided by the reference is preferred, but sometimes it isn't available. Lithopsian (talk) 16:53, 30 April 2020 (UTC)

What is DSKE?

Radius calculated from disk emission? In what way? In what way is this different from the other methods? Of the three stars tagged this way, two appear to have radii calculated from the temperature and luminosity, while one has an angular diameter. Lithopsian (talk) 20:10, 1 May 2020 (UTC)

Ask Ardenau4 (talk · contribs), it seems to be taken from his Google Docs list. SevenSpheresCelestia (talk) 19:27, 3 May 2020 (UTC)

Semi-protected edit request on 3 May 2020

Can you add the follwing red supergiants that are located in the cluster Stephenson 2 since their radii are calculated to be above 700 R based on bolometric luminosity and effective temperature per this paper https://arxiv.org/abs/1209.6427:

  • Stephenson 2-03 - 969 R (from Lbol of 160,000 L and 3,700 K)
  • Stephenson 2-04 - 710 R (from Lbol of 85,000 L and 3,700 K)
  • Stephenson 2-11 - 884 R (from Lbol of 130,000 L and 3,700 K)
  • Stephenson 2-14 - 821 R (from Lbol of 91,000 L and 3,500 K)
  • Stephenson 2-18 - 2,150 R (from Lbol of 440,000 L and 3,200 K)

2A01:E0A:47A:F100:DC55:2580:CDC4:96A2 (talk) 23:51, 3 May 2020 (UTC)

 Done Nussun05 (talk) 04:54, 4 May 2020 (UTC)

V538 Carinae

There is a star called V538 Carinae and it has Gaia data at 1,885 solar radii. Should it be added to the list?Nussun05 (talk) 07:15, 5 May 2020 (UTC)

Are you sure about that? Lithopsian (talk) 16:22, 5 May 2020 (UTC)

Idk i just saw it in jsdc.stc for Celestia which was derived from Gaia dataNussun05 (talk) 16:49, 5 May 2020 (UTC)

Unreliable source. This is the Gaia DR2 entry for V538 Carinae. There isn't really enough data there for a good calculation of its radius. Lithopsian (talk) 18:52, 5 May 2020 (UTC)

Find new stars to add?

Could someone look in references of stars to find ones that have a radius of more than about 1300 solar radii? It's really getting boring with just the same stars at the top of the list and i want someone to find new stars to add. If stars of 1300 sr or more can't be found then just look for stars above the 700 sr limit. Nussun05 (talk) 18:13, 21 May 2020 (UTC)

That's... not really how that works; we can't just make up a star to "keep things interesting". Primefac (talk) 22:09, 21 May 2020 (UTC)

I checked on quora some time ago for stars bigger than UY Scuti, a guy called Sam Halls had put up a post with lots of stars. I could not find the source though. One of the stars was WOH G55, is that even a star? — Preceding unsigned comment added by 122.111.254.1 (talk) 03:15, 29 May 2020 (UTC)

Semi-protected edit request on 29 May 2020

Please can I be able to edit? I really love making list and love size. PNSMurthy (talk) 03:22, 29 May 2020 (UTC)

 Not done: this is not the right page to request additional user rights. You may reopen this request with the specific changes to be made and someone will add them for you, or if you have an account, you can wait until you are autoconfirmed and edit the page yourself. RandomCanadian (talk / contribs) 03:32, 29 May 2020 (UTC)

I do not understandPNSMurthy (talk) 03:45, 29 May 2020 (UTC) — Preceding unsigned comment added by PNSMurthy (talkcontribs) 03:34, 29 May 2020 (UTC)

Proposal to lower the 700 solar radii limit down to only 200

I suggest we lower it to 200 so we can add a lot more stars, that way people would be able to find the radii of the stars way easier since they don’t have to look themselves in other places. Nussun05 (talk) 18:57, 28 May 2020 (UTC)

This is a list of the largest stars, not "any star we want to list". Last time we discussed the issue the consensus was to keep it at 700. Primefac (talk) 19:18, 28 May 2020 (UTC)

Excuse me, I would just like to know about the stars below 700 that are not on this list. Do you have some sort of catalogue that you could post on the site?PNSMurthy (talk) 03:27, 29 May 2020 (UTC) I kinda support this, can you guys bring it down to 400, not 200, because stars below 400 are very plentiful, and our list will be to big with them. Can we make it 400?PNSMurthy (talk) 03:44, 29 May 2020 (UTC)

@PNSMurthy: I appreciate you suggestion, but this shouldn't became just an indiscriminate list of large starts - Wikipedia isn't a stat book and the list should be kept to a manageable size. Given there are already, by my quick estimate, well over a hundred entries, I don't think it would be helpful to add even more by lowering the threshold. What we could do, however, without increasing the size of the list, is pointing readers towards reliable external databases which list this information, either as a link in the "External links" section of the article or as a "Further reading" section. RandomCanadian (talk / contribs) 04:32, 29 May 2020 (UTC)

Semi-protected edit request on 29 May 2020

request edit I am not sure if this is the way I request an edit, but heer I go, I would like to change a few citations and sizes if needed, and help expand the listPNSMurthy (talk) 03:38, 29 May 2020 (UTC) PNSMurthy (talk) 03:38, 29 May 2020 (UTC)

Do any of you guys know the star AZ Cephei. I am currently still searching for the source but many cites cite it as over 1400 radii. There are a few more stars like this, like a previously mentioned WOH G55. Should we add them, or do we need a document of a scientist to be able to cite them properly, or will any site fit? — Preceding unsigned comment added by PNSMurthy (talkcontribs) 03:42, 29 May 2020 (UTC)

 Not done. It's not clear what changes you want to make. Please be specific and precise, and please provide reliable source(s) that support any additions you want to make. –Deacon Vorbis (carbon • videos) 03:46, 29 May 2020 (UTC)

Ok thanks, that was my question, I will sniff out the sources then come back to youPNSMurthy (talk) 03:56, 29 May 2020 (UTC)

S Persi for ~700radii and Massey et all VY Canis Majoris

Don't some estimates base S Persi on 700 radii, and shouldn't we take the lower estimate? Massey et all based Vy Canis Majoris on the fact that it is a giant, rather then a extreme hypergiant, and suggests a much lower estimate of 600 radii. Also, doesn't Chi Cygni have a 700+ radii estimate?PNSMurthy (talk) 03:55, 29 May 2020 (UTC)§

Also again, isn't Gaia data inaccurate at such measurements such as size? Should you really use its scale?PNSMurthy (talk) 03:59, 29 May 2020 (UTC)

From what I can comprehend of the above comments, user is seeking to add AZ Cephei (and potentially a few other celestial objects) to this list. Regarding AZ Cephei's radius, the only RS which I could find ([1]) does not list anything on that subject. It would require that User:PNSMurthy provide us with some proper citations to a reliable source. Cheers, RandomCanadian (talk / contribs) 04:08, 29 May 2020 (UTC)

Ah, yes, that's what I am searching for, I can give you it, it is here. It is not reliable, and I am searching for a reliable sourcePNSMurthy (talk) 04:12, 29 May 2020 (UTC)[1]

Cheers to you too!PNSMurthy (talk) 04:13, 29 May 2020 (UTC)

Also, to clarify, I'm not an expert in astronomy so I can't really help you on the subject. If you are seeking answers to questions on the subject, I might point you gently in the direction of the reference desk, since this page is about discussing improvements to the article, not as a general forum to discuss the subject. If you wish to suggest some additions to the article and you have a source to cite ("Massey at al." seems like one) ideally it would be a full citation and not just author names, but failing that even something as simple as a DOI or a url to the paper/ressource you are mentioning could be helpful. Thanks, RandomCanadian (talk / contribs) 04:17, 29 May 2020 (UTC)

By the way, here is the link for the Massey et all VY Cma:[2]PNSMurthy (talk) 06:32, 29 May 2020 (UTC) PNSMurthy (talk) 06:33, 29 May 2020 (UTC)

I'm liable to trust a 2012 paper over a 2006 paper, if only because of the technological advances that get made over such time periods. I do see there's a reasonably large error on the larger value, but since the 600 is already included for reference I think the entry can be left as-is. Primefac (talk) 13:56, 29 May 2020 (UTC)
Agreed. This idea never gained traction and consensus now is that VY CMa actually is a very luminous and large star, exact radius TBD but likely very close to the number they first thought of. Lithopsian (talk) 19:51, 29 May 2020 (UTC)

References

  1. ^ youhttps://www.quora.com/Are-there-any-stars-bigger-than-UY-Scuti-that-have-been-discovered
  2. ^ Massey, Philip; Levesque, Emily M.; Plez, Bertrand (August 2006). "Bringing VY Canis Majoris Down to Size: An Improved Determination of Its Effective Temperature". The Astrophysical Journal. 646 (2): 1203–1208. doi:10.1086/505025.

I calculated the size of AZ Cephei to be only 860 solar radii Nussun05 (talk) 14:01, 29 May 2020 (UTC)

"I calculated ..." is a bit of a giveaway. Wikipedia doesn't allow original research or synthesis and any calculations which are not immediately obvious and unambiguous are likely to be one or the other. I'm guessing that you calculated the radius from a distance and an angular diameter, derived from different sources although presented in a single database with little to no sanity checking. Pretty dodgy, although AZ Cep is far from the worst example. Lithopsian (talk) 20:02, 29 May 2020 (UTC)
See WP:OR. @Primefac: I don't know, 6 years is not such a massive time difference. I have rewritten the text I added a bit. Anyway these are very distant objects on which I guess we only have limited information, so the information is by its nature only an estimate, since the only star for which we can verify it is the one shining outside right now. Cheers, RandomCanadian (talk / contribs) 14:47, 29 May 2020 (UTC)

Month 3 of restrictions and people think VY Cma is only 650 radii, the level of madness in me has amped upPNSMurthy (talk) 01:25, 31 May

2,163 solar radii for Stephenson 2-18?

Nussun 05, a few days ago, I saw you undo Faren29's edit on Stephenson 2-18's size of 2,163 solar radii.However,I support Faren29 because of a dispute; the 2,158 solar radii size estimate is based on this: square root of 5772 (solar temperature)/3200 (Stephenson 2-18's temperature) ^4*440000(Stephenson 2-18's luminosity)= 2,158 solar radii, BUT,the solar temperature is 5778,NOT 5,772 kelvin/celsius. with the formula, which is square root of ((5778/3200)^4*440000=2,162.62 solar radii, and if you round it off, it equals to 2,163 solar radii.User:122.2.30.162 —Preceding undated comment added 04:07, 4 June 2020 (UTC)

You can't do that in Wikipedia, check the rules PNSMurthy (talk) 07:47, 4 June 2020 (UTC)
Nominal solar effective temperature is 5,772 K according to the IAU.[1] Regardless of the actual surface temperature, this is the value that should be referred to when expressing temperatures relative to the sun. This shows the perils of calculating values even when it seems simple and obvious. Lithopsian (talk) 09:48, 4 June 2020 (UTC)

References

  1. ^ Prša, Andrej; Harmanec, Petr; Torres, Guillermo; Mamajek, Eric; Asplund, Martin; Capitaine, Nicole; Christensen-Dalsgaard, Jørgen; Depagne, Éric; Haberreiter, Margit; Hekker, Saskia; Hilton, James; Kopp, Greg; Kostov, Veselin; Kurtz, Donald W.; Laskar, Jacques; Mason, Brian D.; Milone, Eugene F.; Montgomery, Michele; Richards, Mercedes; Schmutz, Werner; Schou, Jesper; Stewart, Susan G. (2016). "Nominal Values for Selected Solar and Planetary Quantities: IAU 2015 Resolution B3". The Astronomical Journal. 152 (2): 41. arXiv:1605.09788. Bibcode:2016AJ....152...41P. doi:10.3847/0004-6256/152/2/41.{{cite journal}}: CS1 maint: unflagged free DOI (link)

Oh, sorry. Anyways thank you for removing WOH G17 & RS Mensae.User 122.2.30.162 (13:34 UTC, 4 June 2020) — Preceding unsigned comment added by 122.2.30.162 (talk) 13:34, 4 June 2020 (UTC)

I found a new source with some stellar radii

https://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=J/ApJ/826/224/table2 I found some radii of red supergiants in the Andromeda Galaxy, one of them had a radius of 1980 solar radii which might make it one of the largest known stars. Since i can’t edit myself now i hope someone else who can will see this message and add them. Nussun05 (talk) 04:34, 5 June 2020 (UTC)

Do name them, and please can someone make this semi-protected, it's really, well hysterical to keep an article like this fully protected, no offense PrimefacPNSMurthy (talk) 04:49, 5 June 2020 (UTC)
You can find the names in the link i sent, just set the max number of objects it displays to unlimited, and then click the submit button to get the radii of the stars. Nussun05 (talk) 04:45, 5 June 2020 (UTC)
Also you are not Primefac you are PNSMurthy. Nussun05 (talk) 04:47, 5 June 2020 (UTC)
I directed that to Primefac, and I did find them, since I cannot add them to the list, I am simply adding them to my own private list Nusson05PNSMurthy (talk) 04:49, 5 June 2020 (UTC)
There is no star with 1980 solar radiiPNSMurthy (talk) 04:54, 5 June 2020 (UTC)
Look at the left side of the page and under preferences, change the number that says 50, and change it to unlimited, btw where can i find this private list of yours? Nussun05 (talk) 05:01, 5 June 2020 (UTC)
On my laptop, unsourced though, and messy at best, still clearing it, it goes down to 5 solar radiiPNSMurthy (talk) 05:10, 5 June 2020 (UTC)
Is there any way for you to make a wikipedia page for them and find sources? Nussun05 (talk) 05:14, 5 June 2020 (UTC)
Well sure, but the sources are varied, and I have done my calculations and added disputed rankings, and , below 600, it becomes extremely messy and sparcePNSMurthy (talk) 05:16, 5 June 2020 (UTC)
If I do ad my list, it won't be below 500, that's the bit I am working onPNSMurthy (talk) 05:18, 5 June 2020 (UTC)

If you add the page you should add it to your sandbox page. Nussun05 (talk) 05:21, 5 June 2020 (UTC)

SurePNSMurthy (talk) 05:23, 5 June 2020 (UTC)
Ah,
there are 2 stars whose sizes are above 1500 (that I found)
They are: J004539.99+415404.1 and J004520.67+414717.3, the former has a solar radii of 1980 and the latter 1870, may they be added to the list?PNSMurthy (talk) 05:38, 5 June 2020 (UTC)

Three RSGs in Sextans A

https://arxiv.org/pdf/1909.13378.pdf (Britavsky et al, 2016) has two RSGs and a YHG(?) in Sextans A over 700 Rsol (870, 995, and 710). I wasn't really able to find any identifiers for these stars - since the page is now protected can someone add these? I would also share my personal list, but right now I'm still working out some details from the new AD paper. Thoughts? Ardenau4 (talk) 15:35, 5 June 2020 (UTC)

YHG? A y-type star? Also, could someone please add the new stars from the M31 article?PNSMurthy (talk) 06:32, 6 June 2020 (UTC)

Oh, yhg’s are pre-rsg stars, yellow hypergiantsPNSMurthy (talk) 06:58, 6 June 2020 (UTC)

The article is protected for a reason. It is time to discuss the way in which the list should be structured and the policies about which stars and which properties should go in it. Not to plough on as before, with the list becoming progressively more meaningless. This may be the time to discuss what to do about stars in external galaxies. It is reasonable to expect that there are more or less the same numbers of equally large stars in any large spiral galaxy and a few in smaller galaxies, and we now have the technology to detect them. Do we want the list to become 10 or 100 times larger and full of stars nobody knows or cares about and that are probably highly inaccurate anyway? Lithopsian (talk) 13:14, 6 June 2020 (UTC)
Good find though, an interesting article. Lithopsian (talk) 13:15, 6 June 2020 (UTC)

I suggest we make a secondary list with stars not yet catalogued, like the one Ardenau4 was talking about, and the stars above 700 in M31. That way, once we have sorted through our list, we can start working on expanding it, I will make a new article for such stars, a sort of waiting list. Finally, the list is already full of stars no one looks at, that’s why they’re all - or most of them - are red.PNSMurthy (talk) 01:23, 7 June 2020 (UTC)

The secondary list is‘[[2]]’PNSMurthy (talk) 01:35, 7 June 2020 (UTC)

arcminute - metre

Hi,

Is there a way of calculating metres if arc minutes are given, I am working through a few tables and am curious if I can find the radius that way. PNSMurthy (talk) 04:42, 7 June 2020 (UTC) — Preceding unsigned comment added by PNSMurthy (talkcontribs) 04:37, 7 June 2020 (UTC)

Use wolframalpha and input ”(distance)*sin(angular diameter)” to get a radius in solar radii type ”in solar radii /2” at the end. If you don’t do the ”/2” it will be the diameter in solar radii making it double of what it’s supposed to be. So that’s why you have to put that there too. Nussun05 (talk) 06:02, 7 June 2020 (UTC)

ThanksPNSMurthy (talk) 06:05, 7 June 2020 (UTC)

Stop adding inaccurate sizes !

I noticed that Stephenson 2-18 isn't the largest anymore. WOH G17 is the largest. Why do people just keep putting inaccurate sizes? I am getting sick of these people . STOP ADDING INACCURATE SIZES ! My madness is coming. Please remove the inaccurate sizes,as they are pissing me off!!!!!A similar case happened when RMC 87F (HD 269942) got added. REMOVE THE INACCURATE SIZES !!!!!!User:122.2.30.162

Lithopsian, please go over the list and please change all stars to their respective sizes. Most of them are not in the right place. KW Sagittarii is 1009, UY Scuti is 755, Mu Cephei is 1260, IRAS 02580-6910 was placed with 1738 solar radii, Stephenson 2-18's size along with WOH G17 are inaccurate, HV 888 is 1353 solar radii, RW Cephei is 981 solar radii, HR 5171 A is 1315 solar radii. Everything is misplaced, please go over the list. I am confused which star is which. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 13:47, 3 June 2020 (UTC)


V255 Canis Majoris and Lithopsian, I am referring to only WOH G17. I don't think Stephenson 2-18's size is inaccurate. UY scuti's size has officially been shrunk. — Preceding unsigned comment added by 122.2.30.162 (talk) 14:00, 3 June 2020 (UTC)

I just looked at the article of WOH G17, and when I looked at the luminosity, it annoyed me so much. the luminosity is 930,000 solar luminosity , which is WAY TOO MUCH ! Lithopsian , please go over it. if you find it inaccurate, revise it. User:122.2.30.162 — Preceding unsigned comment added by 122.2.30.162 (talk) 14:26, 3 June 2020 (UTC)

Usually luminosities are given as log(L), and this one is just giving it as L. Perfectly acceptable. Primefac (talk) 14:39, 3 June 2020 (UTC)
Dear Lithopsian, please check WOH G17's size. If you find it inaccurate, then please remove WOH-G17. That's all I wanted. Thanks! User 122.2.30.162
Will check, but as I just said above (slight edit conflict) it seems reasonable. Primefac (talk) 14:39, 3 June 2020 (UTC)

NO, WOH-G17's size is too large, it is too bright, so I think this is inaccurate. Its properties are unreasonable and unacceptable. — Preceding unsigned comment added by 122.2.30.162 (talk) 14:47, 3 June 2020 (UTC)

Could someone please remove WOH-G17? [[User:122.2.30.162 — Preceding unsigned comment added by 122.2.30.162 (talk) 14:55, 3 June 2020 (UTC)

Goodness gracious, calm down. I'm in the middle of a meeting and can't check it right this instant. Primefac (talk) 14:56, 3 June 2020 (UTC)

Ok. If I do not see it removed, I am going to remove it myself ! User 122.2.30.162 — Preceding unsigned comment added by 122.2.30.162 (talk) 15:12, 3 June 2020 (UTC)

You're welcome to do the calculation yourself, but if a star has a luminosity of 932967 L and an effective temperature of 3300 K, it works out to a radius in the neighbourhood of 2900 R. Primefac (talk) 15:40, 3 June 2020 (UTC)
In fairness, though, I ran some of the other numbers and MSX LMC 1677 ends up with a radius of about 6400 R, which is rather unreasonable. Primefac (talk) 15:53, 3 June 2020 (UTC)

All those sizes V255 Canis Majoris mentioned are not the most recent ones and not the most accurate ones. He just says to change back because he likes those sizes more Nussun05 (talk) 16:51, 3 June 2020 (UTC)

In all fairness, UY Scuti is only 700 radii, the 900 estimate is slightly older (I think)PNSMurthy (talk) 02:33, 4 June 2020 (UTC)

Looks like WOH G17 has been removed. Thank you Lithopsian !User:122.2.30.162 — Preceding unsigned comment added by 122.2.30.162 (talk) 03:04, 4 June 2020 (UTC)

Excuse me Nussun05, I am not cherry picking the sizes I wanted. Click those stars and go to their personal articles. The sizes I mentioned are still written there. Take RW Cephei and UY Scuti for example. In the list, I see them at 777 solar radii and 941 solar radii but when I click their articles, it still says 981 and 755 solar radii. If you're going to change the size of the star, do the same inside the article. There have been many false edits here and I am getting confused. I plan to make more star size comparison videos in the future so this is important. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 08:48, 5 June 2020 (UTC)

The pages just haven’t been updated yet, they really should. Using those sizes just because they happen to be in the pages is probably still cherry picking. — Preceding unsigned comment added by Nussun05 (talkcontribs) 14:53, 5 June 2020 (UTC)

It's only cherry picking when you deliberately choose the size you wanted. I only tried to question which radius was factual because of the many false edits years back. V255 Canis Majoris (talk) 07:18, 6 June 2020 (UTC)

That's exactly what you did Nussun05 (talk) 12:49, 6 June 2020 (UTC)

Did what? If the articles had been edited properly and accordingly, I wouldn't edit the list. I gave 1936 for VY Canis Majoris because of the computation I've made. It was not random. V255 Canis Majoris (talk) 07:49, 8 June 2020 (UTC)

Is the 474 solar radii estimate for Stephenson 2-18 referring to another star?

When I clicked on Stephenson 2-18's article, the 474 solar radii estimate, Lithopsian said, was referring to another star different from Stephenson 2-18 . But when I saw the list of largest stars, the 474 solar radii estimate is still there . Can someone please edit the part where the 474 solar radii estimate is? — Preceding unsigned comment added by 122.2.30.162 (talk) 05:06, 9 June 2020 (UTC)

I do think that it was an obsolete/ old (on astronomical standards) article that stated that parameter. The article being used to assume that Steph-2-18 is over 2,000 radii might be more accurate and precise. You never know though, it might have been a typo and that size might be referring to another star, and it is biased to assume one of the articles in question is more accurate than an other, but it is unlikely.PNSMurthy (talk) 06:47, 9 June 2020 (UTC)
PNS Murthy, check the view history. It says that at 20:00 UTC, Lithopsian edited it and I saw that he removed the 474 solar estimate. The edit summary of the edit says that He removed the 474 solar radii estimate because it was referring to another star.User: 122.2.30.162 —Preceding undated comment added 08:02, 9 June 2020 (UTC)
If you are referring to the name-sake star's article, I will check shortly, I was not aware of anything of the such on this site - I have now checked the history, I am not sure why Lithopsian would have stated /done that, he probably has his/her reasons and the article might indeed be refrring to a differnt star when it states that estimate, but I am not aware of it.PNSMurthy (talk) 08:07, 9 June 2020 (UTC)
Well Lithopsian, if you are awake, please explain the removal of the 474 solar radii to PNSMurthy. Ok?User122.2.30.162 — Preceding unsigned comment added by 122.2.30.162 (talk) 08:32, 10 June 2020 (UTC)
Well...you people are on the other side of the world, I am going to sleep now! It's 6:37 (P.M.)!PNSMurthy (talk) 08:38, 10 June 2020 (UTC)
Ah, I have read the original (DFK) article, and I think I see the mistake. The users who edited this list (including me) probably assumed that Steph 2-18 is the same star as Steph 2-DFK18. But in that paper, this discussion’s namesake star is the first on the list (DFK-1 not 18). It is indeed a mistake.PNSMurthy (talk) 09:31, 11 June 2020 (UTC)

Grammatical errors

Could someone who is able to edit this list please change the description of V382 Carinae from 'Yellow hypergiant, one of the rarest types of a star.' to 'Yellow hypergiant, one of the rarest types of stars.' and fix the description of Betelgeuse in the caption, changing 'though Betelgeuse smaller then Antares as seen in recent studies.' to 'though Betelgeuse is smaller then Antares as seen in recent studies.'

Thanks! — Preceding unsigned comment added by PNSMurthy (talkcontribs) 08:28, 12 June 2020 (UTC)

 Done. Primefac (talk) 19:27, 15 June 2020 (UTC)

Thanks for the corrections Primefac, but it seems the former has not been corrected, when you edit the list next time please change that too:) - never mind, you have changed it - sorry!PNSMurthy (talk) 01:53, 16 June 2020 (UTC)

RSG's and other large stars in RSGC-3, Alicante 8, Trumpler and W1

Hi guys,

I have just been looking at the list and I see that there are only stars from RSGC-1 and 2 (Steph 2), and no stars from any other clusters. It seems strange to me, that even though their respective Wikipedia articles state that RSGC-1 to 4 are all full of supergiants (hence the name), only two of those cluster's stars are present on this list. Could someone please find more star from these clusters? Also, isn't there an article talking about supergiants/ hypergiants in Westerlund 1 with sizes over 2,000 solar radii. Finally, it also seems queer to me that only one rsg in a whole cluster (Trumpler) is present. It seems to me that there are many more stars in these clusters that haven't been catologoued. Again, could someone please find and/or add these 'phantom' rsg's, rhg's and possibly yhg's to the list?

Thanks! PNSMurthy (talk) 08:31, 9 June 2020 (UTC)

I have found a table in research gate on rsg's in Alicante 8 that shows only the amount of arc - seconds. Is their a way to find the solar radii of these red supergiants with only this?PNSMurthy (talk) 08:31, 9 June 2020 (UTC)

On the same site, I have also found a chart by Negueruella et all that shows a chart of 8 rsg's. It is seen here:[1] PNSMurthy (talk) 08:39, 9 June 2020 (UTC)

This sounds really exciting. Can't wait to see them. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 02:53, 11 June 2020 (UTC)

I’ve checked the article, and the 2,000 solar radii is referring to Westerlund 1-26 and not any other stars in the Westerlund 1 cluster. Nussun05 (talk) 09:44, 13 June 2020 (UTC)

Oh, fair enoughPNSMurthy (talk) 09:47, 13 June 2020 (UTC)

You said Westerlund 1-26 is 2000 solar radii? But it is 1530 solar radii! Does this mean Westerlund 1-26 is the second largest star now?

It is a possibility, not confirmed yet though and probably never will be, so you cannot catalogue 2,000 as its true size, that would be cherry picking. Westerlund 1-26 is already estimated to go past 2,000 at most, so this doesn't change anything. The size that is currently there will stay.:)PNSMurthy (talk) 01:07, 14 June 2020 (UTC)

I didn’t say Westerlund 1-26 is 2,000 solar radii, that’s just what it said in that ref. Nussun05 (talk) 04:05, 14 June 2020 (UTC)

All stars on this list (atleast the ones above Jupiter's orbit) have a significant region of doubt and most of their sizes are either just the middle size or apporximations. Westerlund 1-26 is already calculated to be above 2,000 radii at its biggest estimate (2,850) and can't necessarily be hailed as the largets star because of the possible (and probable) inaccuracy in calculating it's parameters. We cannot just take all stars by their largest size (this is why Westerlund 1-26 has not been placed with it's highest estimate) - though it once was. The article which state's it's size as possibly above 2,000 has just placed it there as the limit, because the range of inaccuracy, like KY Cygni, NML Cygni and VV Cephei A, is extremely high.PNSMurthy (talk) 05:32, 14 June 2020 (UTC)

There is another article I found on google scholar discussing large stars, here it is.[2]PNSMurthy (talk) 07:24, 16 June 2020 (UTC)

Edit request

Grammar fix: in the caption for the image in the lead, "thought to be smaller Antares" should read "thought to be smaller than Antares" (add than before Antares to complete the comparison). ComplexRational (talk) 01:53, 21 June 2020 (UTC)

 Done Primefac (talk) 01:56, 21 June 2020 (UTC)

Submissions

If anyone has some submissions for stars that you would like to be part of the list, say the star name and size in User talk:Nussun05/The Large Stars Quest, and I will try to verify them, please provide reliable refs. I will add submissions to Talk:List of largest stars/New List when and if they are verified. Nussun05 (talk) 11:48, 23 June 2020 (UTC)

V538 Carinae radius

Why is the given radius for V538 Carinae in this list at 1,870 R and on its page at 580 R? Maybe someone should fix this. MuCepheiBetelgeuse (talk) 10:12, 22 June 2020 (UTC)

The smaller value is based on the Hipparcos parallax and the larger one on the Gaia DR2 parallax. Both are inaccurate to the point of being useless. V538 Car is apparently an AGB star, a long period variable, and hence likely to be a luminous giant rather than one of the largest known supergiants. Lithopsian (talk) 15:08, 22 June 2020 (UTC)
Welp, I wonder who say that it is an AGB star (and likely much smaller than 1,870 R). 2A01:E0A:47A:F100:2090:F8C5:735B:4640 (talk) 15:24, 22 June 2020 (UTC)

Should it be changed then? Maybe moved to notable stars below 700 R? MuCepheiBetelgeuse (talk) 13:16, 23 June 2020 (UTC)

Discuss what the policy should be on choosing sources, picking a single value or a range, and what they should be sorted by. The free-for-all editing of the list wasn't improving things, so it is locked until the way forward is more clear. There is also Talk:List of largest stars/New List which is sort of a sandbox for hashing out ideas on how the list might look. V538 Carinae can still be edited, of course. Having a well-sourced article which fully explains the consensus (or not) physical properties of a star is always going to make it easier to put it in this list. Lithopsian (talk) 14:09, 23 June 2020 (UTC)

Speaking of GaiaDr2, isn't there a stars with a radius of 2800 present in the catalogue? Should it be added?PMurthy1011 (talk) 08:39, 24 June 2020 (UTC)

With the help of some friends, I was able to check all radii in Gaia DR2, and the largest of them was only about 700 solar radii, so I do not know where that size comes from, we cannot add it until it is verified and we know what star it is. Nussun05 (talk) 12:50, 24 June 2020 (UTC)

Your friend needs to try harder: IM Cas. Generally though, Gaia doesn't display a radius when the distance or other relevant properties are uncertain, which it almost always is for red supergiants. Almost all the large stars shown in these other sources have no radius displayed in Gaia DR2, an indication of how meaningful (or meaningless) they are. Lithopsian (talk) 11:05, 25 June 2020 (UTC)

Is IM Cassiopeia the stars in question? - ah, no, it is only 700 r, sorry!PMurthy1011 (talk) 05:32, 26 June 2020 (UTC)

Im sure that size is INACCURATE ! — Preceding unsigned comment added by 122.2.30.162 (talk) 15:00, 24 June 2020 (UTC)

It probably is, no star can sustain such a large sizePMurthy1011 (talk) 05:54, 25 June 2020 (UTC)

Edit request - SMC 5092

Could someone please change the star SMC 5092 from being simply 'SMC 5092' to; SMC 5092?PNSMurthy (talk) 23:43, 27 June 2020 (UTC)

Page doesn't exist, no reason to link to it. Primefac (talk) 16:58, 28 June 2020 (UTC)

It's for consistency. A hundred stars have links whilst this lonely one doesn't. :)

But any way, it doesn't really matter.PNSMurthy (talk) 00:25, 29 June 2020 (UTC)

Reset the list

I think we should restart the entire list and remove everything. Then we can get rid of all the possible accurate info and actually make a good list of largest stars for once. The admins can find and check sizes of stars and add them when they have been verified. This would probably make the list much much better. Nussun05 (talk) 11:44, 29 June 2020 (UTC)

Has anyone other than me checked the "new" list of stars for accuracy? I started the other day and kept edit-conflicting, but there are a few of the J00... stars that aren't even listed in the supporting references. That being said, the new list is of a decent length that if things are reaching some semblance of accuracy we can start porting them over. Primefac (talk) 14:55, 29 June 2020 (UTC)
I haven't had chance to look at the list in any detail. Starting at the top didn't inspire me with confidence. RW Cephei is a problematic star with an apparent K-type hypergiant spectrum (MK standard star for K2 0-Ia); it is variable by over a magnitude and has an uncertain distance. The entry in the new list appears to be derived from a luminosity in a very old source and an effective temperature in a fairly new one, whilst ignoring the much lower luminosity in the newer source. Combining data from different sources in this way is skirting very close to WP:SYNTHESIS and should be an absolute last resort; doing it when one of the sources contains both a temperature and a luminosity is unacceptable. There are many difficulties with the rather sparse sources for this star (not least with the two sources used), some of them discussed at RW Cephei but the radius used in this list is the most blatant cherry-picking. Lithopsian (talk) 20:33, 29 June 2020 (UTC)
Just as a follow-up, I've edited RW Cephei with a very new reference that gives an actual radius. It isn't perfect as its a fairly trivial analysis based on Gaia DR2, but it is better than multiplying out a temperature from one source and a luminosity from the middle of the last century. Lithopsian (talk) 20:04, 30 June 2020 (UTC)

I‘m not even sure if the new list was even needed. There were hardly any ‘revised’ star added, only new star, some of them with possibly unreliable sizes. But, I guess we can get back on track now...PNSMurthy (talk) 00:39, 30 June 2020 (UTC)

Yep. Nussun 05 was adding inaccurate sizes both on the old list and the new one. Especially those I mentioned, like RMC 87F, WOH G17, WY Geminorium, WOH G347, HD 270422, And An inaccurate size for RW Cephei. What shall we do to make him stop adding inaccurate sizes ? He seems to be messing up with the new list as well !!!!!!! User 122.2.30.162 5:42 UTC, June 30, 2020.

1.) Those stars are removed.

2.) Inaccuracy is expected. Anyone might make mistakes.

3.) Those stars might be accurate. You never know User 122.2.30.162 .

Keep that in mind.

Thanks!PNSMurthy (talk) 06:40, 30 June 2020 (UTC)

Unnecessary

Did you just assume my gender? Nussun05 (talk) 06:46, 30 June 2020 (UTC)

Me?!PNSMurthy (talk) 06:53, 30 June 2020 (UTC)

The other guy Nussun05 (talk) 07:59, 30 June 2020 (UTC)

Did you just assume his gender?! PNSMurthy (talk) 08:35, 30 June 2020 (UTC)

Okay so i am actually mtf transgender so i’m technically not a he. Nussun05 (talk) 14:36, 30 June 2020 (UTC)

The point of the "new" list, as well as the template it calls, is so that if there is a question of if something is totally off or incorrect (etc), we can point to specific values given in the reference, rather than having to play "how the heck did you get 2400R?!? Primefac (talk) 16:42, 30 June 2020 (UTC)
Indeed, but it appears to have become simply a new location for the same edit wars that were forced out of the main article when it was locked down. The new template does make it easier to track down where strange new numbers are coming from. Lithopsian (talk) 20:06, 30 June 2020 (UTC)
True, but hopefully after this is implemented productive discussions will be more likely to happen, and (if anything) having the "raw" data will better allow us to create ranges and add more descriptive notes about potential sources of error. And if it's simply not possible to come to any sort of consensus about a star (or its backing research), it should probably be removed. "We don't know how large this star is" is an acceptable third option on this page (maybe have its own prose section about "contentious star radii"). Primefac (talk) 20:32, 30 June 2020 (UTC)

Yep. Nussun 05 is my nemesis. He is adding alot of inaccurate sizes !!!!!!!!!!! He is likely the cause of the edit war on this page and as a result, the list is now messed up a number of times !!!!!!!!! We shall also protect the new page and BAN NUSSUN 05 FOREVER !!!!!!!!!!!! User 122.2.30.162 5:01 UTC July 2 2020.

Please stop referring me to the wrong gender. Nussun05 (talk) 11:27, 2 July 2020 (UTC)

VY Cma

Hi guys,

On this namesake star's article, the luminosity is shown as 178,000 - which corresponds to a size of 1,160 solar radii (rounded). I would like to know if this is the new size of the star, or not, because there have been cases (WOH G64), where the luminosity has been underplayed. Since this star is an extreme hypergiant (though stars like NML Cygni and S Persei are considered hypergiants, even though they posses smaller radii), should it stay with the same size (from Wittowiski et all)?

Thanks,

PNSMurthy (talk) 03:37, 2 July 2020 (UTC)

The reference for the new luminosity figure does not give a radius. Or a temperature for that matter. The older reference gives a radius. It is preferred to use references that actually published a peer-reviewed value rather than us calculating one. We certainly should avoid calculating a radius based on a luminosity and temperature from different sources. So yes, the new luminosity does suggest a smaller radius, but the SED fitting may implicitly be based on a different temperature, so who knows. The star is also variable (at visible wavelengths) by three magnitudes. That suggests there could be at least a small variation in bolometric luminosity, and it may also pulsate and almost certainly changes temperature. As intriguing as all that might be, the article just reports what is contained in reliable sources. Unfortunately, reliable sources haven't fully described the variations, just picked a few observations and calculated based on these. In most cases (certainly the two we're talking about here), the observations have been at widely differing times without much explanation of whether the star was at maximum, minimum, or other, at those times. Lithopsian (talk) 12:04, 2 July 2020 (UTC)

Hmm, yes, does go against WP: Synthesis too. Different assumptions might have been made too. I only just realised the temperature was still taken from Wittowiski et all.PNSMurthy (talk) 01:09, 3 July 2020 (UTC)

Full protection - time to hash this out

I have fully protected this page because honestly, the back-and-forth over the last week or so is unnecessary and a little ridiculous. I'm not going to un-protect it until we have come to some decisions on things. The biggest issues seem to be:

  1. Ranges - yes or no?
    1. If yes, do we sort by largest or smallest
    2. If no, which value do we use? (point #3)
  2. Methods of detection - which to use? (e.g. do we prioritize EB > AD > L/T?)
  3. Values (and this goes with #1.2) - which to choose? What makes a reference "more reliable" than another?

There are other things to discuss which were brought up in a parallel discussion at WT:AST, which I am transcluding below.

Transcluded section from WT:AST § List of largest stars

I'm seriously debating nominating List of largest stars for deletion. As Lithopsian will likely attest, it is a hotbed of OR, edit warring, and incredibly varying measurements. In the last month I've seen a star be pushed to the top of the list, then the bottom, then removed entirely, then re-added somewhere in the middle before finally returning to the top, all based on which reference the involved editors happened to choose as their preferred values for calculating L/Teff. While I have no doubt that this list is (on paper) a notable list (because we do have "largest X" for just about everything), but I just don't feel like (in reality) it's supported reliably enough to be a valid resource. I thought I'd solicit some thoughts here before I pulled the trigger, if only to spitball ideas for potential improvements and/or things to propose at an AFD. Primefac (talk) 13:52, 2 June 2020 (UTC)

Believe me, I appreciate the sentiment, but is a (let's assume) notable article going to be voted off Wikipedia because it is low quality? As in an insider, I find it impossible to guess what an outsider would make of the article. Is it a complete basket-case or are they going to say it needs more effort to resolve the content disputes? What would be the rationale to delete? WP:OR? Would probably fail since it can all be found in reliable sources. WP:SYNTHESIS? Plenty of that, but it can be weeded out. WP:NPOV for cherry-picking sources? Lithopsian (talk) 14:49, 2 June 2020 (UTC)
Well, that last point is the main issue. I'll take Stephenson 2-18 as the continuing example - two references five years apart both measure L and Teff that either give a diameter of 474 or 2158R (see Special:PermaLink/959640933 for refs). Both are "reliable" in that (as near as I can tell) their methods are sound and the papers are published in reputable journals. There's an editor who (in my opinion) wants to "weed out" any "small" numbers for references and only choose the largest numbers possible, while a different editor wants to do the opposite. Do we mandate that the only sizes we post have to be verified by at least two sources (within a margin of error)? Primefac (talk) 15:32, 2 June 2020 (UTC)
So I was taking a look at Stephenson 2-18 today and it seems that the 474 number is for a different star. Might need to find a different pathological example to show how bad things are out there. Not that it makes 2,158 R any more believable, just not flatly contradicted by any sources we have so far. Lithopsian (talk) 20:51, 7 June 2020 (UTC)
Dear Lithopsian, A pathological example of how bad things are out there is V538 Carinae, with a size possibly pushing it to 3rd or 4th, at 1,870 solar radii BUT... There is another source that says it is only 580 solar radii, smaller than Betelguese! Plus, another example of how bad things are out there is HV 888 with 1,353- 1,974 solar radii. If you have seen that "Awful-Botched piece article by Sam Halls on Quora", To quote Lithopsian, Don't trust it to the bone. Sam Halls placed Stephenson 2-18 at 1,630 solar radii, When in reality it was based on A synthesis of published material, banned by Wikipedia, as well as Silly imagination. One of the sources Sam Halls used, as Lithopsian said was for an entirely different star ! And he was embarrased where that 1,630 solar radii came from ! Another thing that makes his article "Botched", To quote Lithopsian again is Sam Halls claiming HV 888 as the largest star,when in reality, It has uncertainty of around 621 solar radii !!!!! (1,353-1,974) --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:52, 15 July 2020 (UTC)
Again, careful. Anything inflammatory might and probably will get you blocked. And, everything doesn't need an exclamation mark. Its not the end of the world.PNSMurthy (talk) 07:34, 17 July 2020 (UTC)
Oops, Once again sorry. It looks like when HV 888 Became 1,477 solar radii I thought: Guess I will have to update My sandbox Again... V538 Carinae might be only an AGB Star and Not one of the Largest stars... --THE COLOSSAL GALAXY NAMED IC1101 (talk) 04:55, 25 July 2020 (UTC)
I'd suggest adding a section at the top for stars with reliable size measurements, presumably due to direct measurements and reliable distances. That way the reader can be informed that the remaining star radius estimates are iffy. Praemonitus (talk) 16:01, 2 June 2020 (UTC)
Wow that's a mess. At the very least those numbers need to report a) the wavelength at which they were measured and b) the uncertainties from their references (even those are probably underestimated in many cases). From the article title I expected to get a list of stars with direct radius measurements from interferometry or occultations, but most of the entries are L/T which is a highly unreliable method of estimation. To address the original question: this is certainly a notable topic so fixing the article would be better than deleting it. If it was deleted, it would soon be recreated, in an even worse state. Modest Genius talk 19:07, 2 June 2020 (UTC)
I would dispute that deriving a radius from a luminosity and effective temperature is highly unreliable. This is the very definition of radius as applied to stars. What is unreliable is using an angular diameter that may or may not bear any relation to what is treated as the radius in any other context. With current interferometric methods, you don't even know if the measurement is of the star or something surrounding the star, whether the star is round or has a remotely uniform surface. And of course all the methods really are highly uncertain in terms of the margins of error on the angular diameter, distance, or luminosity. The effective temperature can usually be derived quite accurately, but trivial derivations from a colour index or two can be wildly wrong. Lithopsian (talk) 14:21, 22 June 2020 (UTC)
I was going to try to find some reliable listing, but unfortunately it seems that all lists of largest stars online are copied verbatim from Wikipedia! Sam-2727 (talk) 18:19, 3 June 2020 (UTC)
This sounds familiar: we had the same situation in the (now-deleted) List of Largest Galaxies. Out of date citations, no consistency in definitions of size, and outright fabrications. The AfD for that list was not very controversial. - Parejkoj (talk) 18:49, 3 June 2020 (UTC)
Give ranges. If the range of reputable sources is 400-1500, then that's what we can give in the list. Sort by largest measurement, I guess, give details where the range is controversial. --mfb (talk) 21:56, 3 June 2020 (UTC)
Please don't try sorting by the most inaccurate available data, that being the largest value you can find. There's nothing inherently wrong with quoting a range, but it doesn't really solve the problem. There are still likely to be multiple (more than two) sources, and those giving values that would constitute the extremes of a range are likely to be exactly the ones you shouldn't be using. Lithopsian (talk) 14:23, 22 June 2020 (UTC)
Correct. As you may know by now, Stephenson 2-18 is my favorite star, Due to it at the top of the list. But if we sorted Stars By their Largest estimate, Its days as Being on the top of the list are numbered. Westerlund 1-26, WOH G64, NML Cygni, KY Cygni, EV Carinae & MY Cephei all have size estimates larger than Stephenson 2-18's, making Stephenson 2-18 drop to 8th :(... The largest size estimates of these stars are 2,550 for Westerlund 1-26, 2,575 for WOH G64, 2,770 For NML Cygni, 2,850 for KY Cygni, 2,880 for EV Carinae and 2,440 for MY Cephei, To name Just a few stars whose size estimates may be larger than Stephenson 2-18's. --THE COLOSSAL GALAXY NAMED IC1101 (talk) 06:54, 17 July 2020 (UTC)
  • I have started a discussion about how to update/fix/display this page, while I won't expect everyone to duplicate their comments here (I'll transclude this section) I would appreciate at least some eyes on it to shoot down bad ideas (or propose good ones). Primefac (talk) 17:49, 4 June 2020 (UTC)
    Primefac and Lithopsian, is there some sort of idea being expressed amongst editors on this topic that large stars are notable (there's a lot on the talk page so I didn't read through all of it)? It might be worth reminding those on the talk page that the stars aren't independently notable. I've Afded I think five or so star articles that are on this list because of lack of independent notability. Sam-2727 (talk) 01:32, 22 June 2020 (UTC)
There's certainly been an effort to create articles, of mixed quality, for many of the redlinks towards the top of the list. In general, I don't think being on the list or even being towards the top of the list automatically confers notability, so WP:NASTRO should apply. I've AfD'd a couple that shouldn't even have been in the list. I've also tried redirecting some of the more pointless stubs, but go some pushback so they're going to AfD as well. I've let a few reasonably-constructed articles be, that probably wouldn't pass the guidelines; still, if there is enough to write an article there's perhaps enough to at least claim some notability. Any thoughts about making a list and submitting them as a batch? Or is it just going to be a trainwreck? So far I haven't seen any opposition to the deletions. Lithopsian (talk) 14:14, 22 June 2020 (UTC)
Just as a note/update, the list has been updated, complete with a new template to calculate the radius based on which values are given in the reference(s). I've checked through the top 5, plus the dozen or so that come from those refs, but more eyes would be helpful in sorting out the validity/accuracy of the new entries. Primefac (talk) 19:53, 12 July 2020 (UTC)

What stars are those? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:40, 15 July 2020 (UTC)

All stars on the list. And, it doesn't seem to be as bad as the late list of largest galaxies (atleast everything is cited).PNSMurthy (talk) 07:34, 17 July 2020 (UTC)

Ok, It is better than that deleted list and the original List of largest stars.Plus, It is sill Semi-Protected and It will not have any Vandalism issues... I have almost 400 edits and could update the List, But if you are asking: why are you not editing the List? It is because I am afraid to mess up the list and add Inaccurate sizes.... THE COLOSSAL GALAXY NAMED IC1101 (talk) 16:23, 24 July 2020 (UTC)

Please try to stay on-topic and discuss the issues without too many side-tangents. If necessary we can split the discussion into specific sub-sections for each major issue. Primefac (talk) 17:51, 4 June 2020 (UTC)

Discussion

What do we do about Stephenson 2-18? The smaller estimate of 474 solar radii would be below the 700 solar radii limit, so it would have to be a well-known star, which it isn’t really. So then it would have to be removed completely from the list, but then people might get confused over why it is not included and someone would probably try to add it back (except not right now since the page is protected). I think we should remove Stephenson 2-18, or add it with the smaller estimate of 474, then HV 888 should be put at 1353 solar radii, and V538 Carinae should be removed or put at 580 solar radii. Nussun05 (talk) 18:51, 4 June 2020 (UTC)

Concerning the methods, one solution might be to make a second table on top of the old one take all the stars with AD estimates in the new list, so that one would be a collapsed list with more accurate estimates. A note on top of the second table should say something about the estimates being slightly less accurate than the other ones. Nussun05 (talk) 19:07, 4 June 2020 (UTC)
Why are angular diameter estimates more accurate? That sounds like original research to me. Lithopsian (talk) 16:16, 6 June 2020 (UTC)
Idk i just heard that once. We could try to read actual relaible sources to see if someone there says that A is more reliable and accurate than B, but the answer is probably way more complicated than that. Nussun05 (talk) 18:24, 6 June 2020 (UTC)
The answer is way more complicated than that ;) Angular diameters are not god-given facts. They are calculated from interferometric models that make certain assumptions about the shape and brightness of the stars disc (eg. uniform or limb-darkened, star spots, etc.), and they are inevitably made at a single wavelength usually in the infrared. Measurements at different wavelengths give different diameters. Stars are not ball-bearings, they are diffuse translucent objects, especially in the infrared. Red supergiants atmospheres in particular are a near-vacuum and are surrounded by gas and dust and plumes that glow in the infrared, they pulsate, change shape, and are hardly spherical at the best of times. Then converting a linear radius, assuming you can get a diameter with a realistic margin of error small enough to make the effort, requires a distance and, despite Gaia, distance estimates for red supergiants are woefully inaccurate. On the other hand, effective temperatures can be reliably measured to within a few percent. Luminosities are a little trickier, but a number of independent methods are available so you have a decent chance to get something sensible, and given the two you have a wavelength-independent radius that is consistent across all stars. I would offer UY Scuti as a case study: derivation of its radius using angular diameter measurements suggested it was the largest known star, but that now appears to have been wide of the mark (note that current distance measurements still have a margin of error of 25% or more and angular diameter measurements vary by a similar factor, so we still don't have a hard-and-fast radius and that is for a relatively close and well-studied star). This could be considered off-topic so feel free to hide if appropriate. Lithopsian (talk) 19:56, 6 June 2020 (UTC)
The longstanding policy has been to sort the list by the smallest value in a range. One of the reasons for this is that it is very easy for a radius to get exploded to unreasonable values, relatively unlikely for truly large stars to be observed as being small. Statistically speaking, the star(s) at the top of any list sorted by the largest estimate are inevitably those with the most inaccurate values, which sort of defeats the point of the list. There are archived discussions about the sort order. Ranges have been less common recently, but I have no objection to them. Having said that, there should be some sanity checks, not just trawling the literature back to the year dot for any possible mention of a stellar size (might not be a problem for many of the more recent discoveries). Which still leaves the issue of selection. Lithopsian (talk) 20:01, 4 June 2020 (UTC)

To be honest, this whole thing can't work. Different methods lead to different estimated and sizes, and over that the sizes of these objects are already highly uncertain. And you can only go by estimates stated in journals and articles, so you have to trust that the journal is accurate, even if it is not. This list if all just a confusing mess. I suggest we make to lists, one with all stars, accurate and inaccurate, and one with verified stars.PNSMurthy (talk) 02:42, 5 July

This discussion seems to be going really slow and not much ways to improve the article have been proposed yet. I think we should create a discord server for this, to make the discussion more fast-paced, so this article can finally become good. Nussun05 (talk) 15:29, 6 June 2020 (UTC)

The 474 solar radii estimate for Stephenson 2-18 was referring to another star different from Stephenson 2-18. The estimate was referring to Stephenson 2 DFK 18, a different star from Stephenson 2-18,AKA Stephenson DFK 1. You guys got confused ! Next time please check your edits before publishing it . User: 122.2.30.162

Calculations

I'm going to somewhat summarize a few of the other threads below (and above) this one - I feel like a lot of the confusion and/or conflict with the solar radii are the origin of the numbers. For example, a calculation has to be made if using L/Teff, so should that calculation actually be included in the code itself? For example, in § 2,163 solar radii for Stephenson 2-18?, there's a discussion about which values were used to calculate S2-18's radius, but if the L and T were given in an #expr, it's much clearer where the numbers originated (and also provide an extra check for typos and mistakes). Primefac (talk) 14:13, 8 June 2020 (UTC)

In other words, instead of saying "Radius = 2,021", say "Radius = {{#expr: (((10^5.64)*3.828e26 / (7.125e-7*3300^4))^.5)/6.957e8 round 0}}" which gives 2021. This could of course easily be done in a template along the lines of {{solRad|LT|5.64|3300}}. Primefac (talk) 14:27, 8 June 2020 (UTC)
Using a template, or at least an #expr, seems like a good idea. I've tended to shy away from footnotes for this calculation, although it won't be obvious to everyone and there are certainly mistakes with the arithmetic in some places. Sometimes though, a radius derived from a temperature and luminosity is actually given in the reference, for example everything in Levesque et al. (2005). Could the existing {{solar radius}} template be expanded to support this? Lithopsian (talk) 15:44, 8 June 2020 (UTC)
That template is just a shorthand way to put [[Solar radius|<var>R</var><sub>☉</sub>]], so... not really? Primefac (talk) 15:57, 8 June 2020 (UTC)
Along the same lines, many recent additions have done calculations from a distance and angular diameter without an actual radius being quoted in the source (eg. Cruzalèbes et al. 2019). This is a little more dubious. There are multiple angular diameters in this source, of different types and from different sources. None of them can be considered to correspond exactly to a Rosseland radius as would be calculated from an effective temperature and bolometric luminosity, although they all aim to get close to that. Some are specifically flagged as being dubious whether they correspond to a measurement of a photosphere at all. It may seem obvious that a radius is just half of a diameter, but really it isn't in such cases. Lithopsian (talk) 15:50, 8 June 2020 (UTC)
Right, and this is where having the actual numbers in our article would help - rather than having to dig through a journal and take a guess as to which numbers were used, having the numbers listed at the very least allows me to confirm the numbers used are "correct". Primefac (talk) 15:58, 8 June 2020 (UTC)

Could someone recalculate the radius for the stars using that method like the 2,021 solar radii for Stephenson 2-18? I would try to do it myself, but the page’s protected. Nussun05 (talk) 18:46, 8 June 2020 (UTC)

There are other things to discuss, but I can get started on a template. If you copy the list onto a subpage of this page (say, Talk:List_of_largest_stars/New List) and start pulling numbers from the sources, that will help. Primefac (talk) 19:29, 8 June 2020 (UTC)

It would be near impossible and/or biased to assume one size is more accurate than another unless the time difference is significant (on the astronomical standard of discovery and revision). The best we can do is see which result matches our calculation (that's the only way I see that makes a logical revision, even though it might break rules and standards set by Wikipedia.) Other than that, we can do nothing more than state the sizes and plot a range - unless we get to meet the authors of this paper and ask their opinion - which we can't exactly do in our current situation:)PNSMurthy (talk) 06:51, 9 June 2020

Back open for business

Thank you all for your cooperation and general patience while a new list was fleshed out. There will undoubtedly be some values under contention (I've already had to comment out about five stars until the numbers can be discussed) but I can definitely say having the calculation template makes checking values much easier. Those who worked on the new list, thank you as well.

The list is a lot smaller than it used to be, but I think it's long enough to be worth copying over and proceeding as usual. I haven't had a chance to check every new entry, but hopefully over the coming days/weeks that can be accomplished. Not exactly sure how we'll mark that (maybe a table or list) but I'll get something posted soon. Primefac (talk) 17:40, 12 July 2020 (UTC)

UPDATE: checklist has been created. Primefac (talk) 22:14, 13 July 2020 (UTC)

Please Tell Nussun 05 to stop adding inaccurate sizes, as she added inaccurate sizes on both the original list and the new list. Since the list is opened up again, we should tell her so she can stop adding inaccurate sizes. Otherwise, She could once again, add inaccurate sizes like that of THA 34-26, whose size was proven inaccurate by Lithopsian  ! --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:37, 13 July 2020 (UTC)

I understand the point of the redlinks in this list - it's an indication that there isn't an article, but there could be one. However, I genuinely don't think stars like J004539.99+415404.1 or SMC 78282 will ever have an article; there's just not enough (and likely never enough) information or interest to actually get a page written (even stars like SW Cephei were redirected here for not having enough information).

I am proposing that the obvious non-starters be de-linked, if only to avoid the sea of redlinks. By "obvious", I mean anything with more letters than numbers (see first two links). Pages like U Arietis will likely never be written, but as a named star in a constellation the chances are much higher than the others. Primefac (talk) 17:45, 12 July 2020 (UTC)

 Done Have partially unlinked the red links, will do the rest soon enoughPNSMurthy (talk) 03:02, 13 July 2020 (UTC)

By the way, what about the largest J00 star? That star deserves an article because its the largest star discovered in the Andromeda galaxy, doesn't it?PNSMurthy (talk) 04:25, 13 July 2020 (UTC)

There have been a few discussions (and even one currently at WT:AST that says size alone is not enough to pass WP:NASTRO. Primefac (talk) 13:14, 13 July 2020 (UTC)

Then, the largest stars in the LMC, SMC and possibly some of the larger ones in the Milky Way have to be scrapped. Only the largest star can stay, I guess.PNSMurthy (talk) 02:15, 14 July 2020 (UTC)

Trustworthy source of UY Scuti size?

UY Scuti has for awhile been considered one of the largest known stars with a diameter of around 1700 times that of the sun. Yet suddenly I see that number changed to 755 times that of the sun based on one source. How reliable is that source? That seems like quite a big difference to attribute to an error in earlier models. I just don’t know if I trust the 755 solar radii number. Jay72091(2) (talk) 02:11, 13 July 2020 (UTC)

Indeed, UY Scuti is no longer considered the largest star. The estimate given by Messineo and Brown is the most recent one we possess, so we are using the number it gives. Though GaiaDr2 indeed has room for inaccuracy, it’s not our job to catalog our the sizes we feel are ‘correct’. Wikipedia is not a platform for people who wish to share their opinions.PNSMurthy (talk) 02:57, 13 July 2020 (UTC)
There is some scope for us to pick references that aren't simply the newest. For example, a reasonably modern in-depth study of a particular star might be considered to give more reliable information than an automated database of a billion stars. We have to take care that we aren't swayed just because we don't like particular values in one reference. It helps if there is a specific reason to consider one reference to be less reliable than another: for example it ignores asymmetric dust extinction or simply picks values to use for modelling rather than producing new values or new observations. In some cases, we may end up using rather unreliable references simply because they are the only ones that actually quote a particular value, for example a radius, rather than us having to calculate one ourselves (see RW Cephei or NML Cygni). In this case, I don't see any reason to dismiss the new value for the radius of UY Scuti: it is essentially consistent with the old number except based on a much closer distance (from the Gaia DR2 parallax) and there seems to be no reason why the old distance should be considered more reliable. Lithopsian (talk) 13:48, 14 July 2020 (UTC)

Yep. i initially doubted it, Basically, "This can't be !" But I eventually moved on and accepted Stephenson 2-18 as one of the largest. UY Scuti was likely NEVER the largest star because Stephenson 2-18's size estimate was published in 2012. --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:33, 15 July 2020 (UTC)

Can of worms

It seems that whilst transferring the new, vetted and verified list to the original list, we have inadvertently removed some stars who had a right to stay. Examples are the stars in RSGC1, Westerlund 1 and Stephenson 2. All of them could be classed as 'verified' and 'accurate', yet, they seem to have magically disappeared. So have EV Carinae, RT Carinae, V776 Centauri Aa, CK Carinae and a whole load of other stars. This list is downright a can of worms, and this whole 'verified' thing needs to be resolved.

And, what about the stars from Levesque et all (the LMC and SMC stars). Are they to be removed because of 'inaccuracy'. Since the Andromeda stars are staying, shouldn't the stars from Levesque et all too?

Finally, what about the stars from Stassun et all? Should all the stars but the THA star be added, or are they also inaccurate?

Please get this resolved soon,

PNSMurthy (talk) 06:46, 13 July 2020 (UTC)

I've already told you, THA 34-26 is inaccurate ! — Preceding unsigned comment added by THE COLOSSAL GALAXY NAMED IC1101 (talkcontribs) 07:17, 13 July 2020 (UTC)
Don't add them ! The margin of error for the parallax is larger than the parallax itself ! Didn't you listen to Lithopsian ????? It seems that you did not listen !!!!! --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:22, 13 July 2020 (UTC)
I meant all the stars but that one - sorry. And that's not the point anyway. You did not understand what I was getting at. I wanted to know whether these missing stars could be added to the list, and whether they are accurate or not. Referring to the 'THA' star, I meant all stars but that. And anyway, there is another star larger than St2-18 in Stassun et all.PNSMurthy (talk) 07:34, 13 July 2020 (UTC)
What star is that? is it RHI84 10-683 ??????? Oh My GOSH ! STEPHENSON 2-18 IS ABOUT TO LOOSE ITS TITLE AGAIN TO AN INACCURATE STAR ! I CAN'T HANDLE THIS ANYMORE !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I'm not angry.--THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:50, 13 July 2020 (UTC)
How is that inaccurate?PNSMurthy (talk) 07:55, 13 July 2020 (UTC)
I don't know ! let's ask Lithopsian ! --THE COLOSSAL GALAXY NAMED IC1101 (talk) 08:17, 13 July 2020 (UTC)
You can't claim an inaccuracy when you don't even know how it is inaccurate. And, who're the scientists here? You, or the authors for this paper? That is, unless your profession is that of a scientist.PNSMurthy (talk) 08:22, 13 July 2020 (UTC)
To answer the question (which I answered on my talk page in a related discussion), it's not that those stars won't ever be added - there are about 180 from the old list that still need to be checked! However, they will need to have their references checked and the L/T or AD values pulled to run through the template. I'm in the process of figuring out a clear way to indicate what has been checked, what has been added to the list, etc, but I got sidetracked yesterday and by the time I returned to that task I was too damn tired. It will happen soon, though. Primefac (talk) 13:17, 13 July 2020 (UTC)

Hmmm, yes, you did clarify this on your talk page. I’ve decided to start working through the old list when time permits. I believe we also have to work through the problem of double stars. If I recall, some stars from the original list have been given new estimates, am planning to put into a word document and then sort through the sizes, because then I can just type up the name in the bar and see if the star’s a double. Thanks for the clarification!PNSMurthy (talk) 02:12, 14 July 2020 (UTC)

The TESS Input Catalog is (should be) a basically reliable set of data. It is based mostly on Gaia DR2 parallaxes and photometry from a variety of sources. It tends to omit data if it cannot be calculated reliably and relatively few stars have physical data shown. As discussed elsewhere THA 34-26 is messed up and shouldn't be used. Lithopsian (talk) 14:16, 14 July 2020 (UTC)
If it is so, then there's a new largest star (refer to The COLLOSAL GALAXY NAMED IC1101's message above for the name) that's dethroned St2-18. I'll add it and the others after the list's major clean up and revision is done. Also, could you please share the ref in which you found out that V538 Car is an AGB variable? I have prevented it from being added to the list on the new list (in the comment section of the checklist), and would like a ref to 1.) prove it, 2.) cite it on its page.
Thanks!
PNSMurthy (talk) 05:54, 15 July 2020 (UTC)
  1. 1.) You need to login to edit. You might be accused of sock puppetry.
  1. 2.) That's not how it works. Just because you don't like it, it doesn't mean it can't stay. If the size is accurate, it will be added. You can't just ask for it not to be added. I could say 'I don't like stars bigger than VY Canis Majoris, I think they're inaccurate. Can we remove them?'PNSMurthy (talk) 06:57, 15 July 2020 (UTC)

Oops, sorry, I forgot to log in !!! What is the size of he above-mentioned star? is it over 2,296 solar radii? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:23, 15 July 2020 (UTC) Let's ask Lithopsian again, as I've said.--THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:23, 15 July 2020 (UTC)

Sure, I was just talking about adding the star. I believe its size isn't 2,300 solar radii. And, I don't see anything wrong with the size.PNSMurthy (talk) 07:42, 15 July 2020 (UTC)

New ref for RSG's

Hi guys,

I found a source that gives the sizes for RSG's (Van Loon et all). Is this accurate? (I am refraining from adding stars because I have allegedly misunderstood the laws of verifying). Could someone verify this?

Thanks!PNSMurthy (talk) 10:06, 16 July 2020 (UTC)

Whoa! WOH G64 is 2,100 solar radii??? and HV 888 only 1,300??? LOL! Sam Halls will be embarrassed seeing this ! LOL LOL LOL LOL LOL Let's Discuss and mock him so he will be forced to Redo his article ! --THE COLOSSAL GALAXY NAMED IC1101 (talk) 14:14, 16 July 2020 (UTC)

Really? Ah, yes, I see it. Though this estimate might be more obsolete then smaller estimates. And most estimates state that HV 888 is around 1,300 solar radii.

1.) Careful, that is extremely rude (If Sam Halls was seeing you now he might report you).

2.) Don't count your chickens before they hatch (though they probably never will), we don't know what these stars' sizes are really. Its extremely hard to accurately measure the average size of a star, and even then there is a wide margin of error.

Please remember that,

PNSMurthy (talk) 01:09, 17 July 2020 (UTC)

Ok, Shall we Discuss about HV 888? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 06:27, 17 July 2020 (UTC)

HV 888? What about it? It does seem to be the lowest estimate yet, but it is also the most obsolete (this is a 1999 paper, the only reason I even asked for it to be verified is because of the other stars in it that do not seem to have other estimates.) I really don't see what there is to talk about. HV 888 isn't a very special star, sure its large, but its not notable. I'm planning on nominating it for deletion (or atleast making the page a redirect), because, as Primefac stated above, size alone does not make any object, or in this case stars, notable.PNSMurthy (talk) 07:30, 17 July 2020 (UTC)

How did the editor get a reference for the size of those stars above WOH G64? Especially NML Cygni, the 1639 solar radii is clearly cherry picking. — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 15:02, 17 July 2020 (UTC)

What do you mean? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 15:26, 17 July 2020 (UTC)

What reference gave NML Cygni's 1639 solar radii? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 18:28, 17 July 2020 (UTC)

NML Cygni still includes 1,640 R as one of the values in the starbox, with a reference. The reference does not publish an actual radius, instead calculating a bolometric luminosity and suggesting two possible effective temperatures. The radius is calculated in Wikipedia and the calculation is shown in a footnote. The exact result of the calculation is 1,638.96. Lithopsian (talk) 18:50, 17 July 2020 (UTC)

NML Cygni is cherry-picking. We are using the Zhang citation whilst ignoring De Beck et all. That’s like using the 1,900 estimate for HV 888 and the Humphrey et all measurement of VY Cma. I really don’t see any difference. And I’m just going to go ahead and add these stars when time permits. No one seems to be answering THE ACTUAL QUESTION.PNSMurthy (talk) 00:56, 18 July 2020 (UTC)

Ok,V255 Canis Majoris, Click on Van Loon et all, there you will see the sizes if scroll down a little. Oops, I meant you should scroll down more, until you see a table. Wait..... All the temperature estimates given are cooler than that of Stephenson 2-18... --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:36, 19 July 2020 (UTC)

On RX Telescopii's page it says that it is 1,900 solar radii. But on the List it still says 682-1882 solar radii ! Plus, Lithopsian said The 682 solar radii was based on a number that is not an angular diameter ! Shall we edit the List ?--THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:52, 19 July 2020 (UTC)

682 is a mistake that would be obvious if the template had been used. I've removed the mistaken value and commented out the whole entry since it does not used a template and the reference does not contain a radius. Lithopsian (talk) 20:01, 19 July 2020 (UTC)

I have a question, Im sure that was put there by SpaceImplorerExplorer, Who put the 474 solar radii estimate of Stephenson 2-18 even if you said it was the wrong star and put the 970 solar radii estimate which we can’t say and a particular IP user who does not want extreme values. My message for them is they need to appreciate the extremities of the universe since the universe is extreme. The smallest star is estimated to be smaller than Jupiter, The largest one (Stephenson 2-18) Estimated To be 3.01Billion Kilometers wide. The smallest Galaxy contains only 1,000 stars and 220 light years across But The largest Galaxy contains 100 Trillion stars and is Millions of Light Years Across. Here, You can see how extreme the universe is ! Why his name Is SpaceImplorerExplorer When he puts Lower Sizes? He even Said that Stephenson 2-18 is just 474 solar radii when in reality it is over 2,150 solar radii! I wonder why he likes that ? THE COLOSSAL GALAXY NAMED IC1101 (talk) 03:32, 23 July 2020 (UTC)

Don't be so inflammatory. No one likes 'dethroning stars'. They just do it to make WP better and more reliable. Keep that in mind.PNSMurthy (talk) 00:29, 24 July 2020 (UTC)

Why is RW Cephei removed from the list? Where did it go? — Preceding unsigned comment added by V255 Canis Majoris (talkcontribs) 10:59, 19 July 2020 (UTC)

RW Cephei needs to be verified. You can do it, if you want to.PNSMurthy (talk) 01:01, 20 July 2020 (UTC)

After all, we don’t want a blatantly cherrypicked value like that 2,269 solar radii estimate. We want a value that is verified, and we want a list that has higher accuracy that that of the old list. The list was fleshed out recently; We don’t want to add inaccurate values. If you want to verify it, use the template, called lList of largest stars row. THE COLOSSAL GALAXY NAMED IC1101 (talk) 16:02, 23 July 2020 (UTC)

RW Cephei wasn't in the new list when it was copied to this article. I think there was some silly value for it and so it got nuked. RW Cephei has a radius that is taken directly from a relatively modern reference, no calculations needed. It should probably be added to the list. Lithopsian (talk) 16:19, 23 July 2020 (UTC)

True. What Nussun 05 Claimed as the most recent properties of RW Cephei was actually one from a new source and an old source. The 2 led to a 2,269 solar radii value but it was blatant cherrypicking. We need to verify the values to put it in the list since we want the New list to be more Accurate than before. I am sure the other stars that were not here are also not verified like RW Cephei. It is still semi-protected, however because of Vandalism issues and like it was Before the list was put under Full protection. We don't want to be in a scenario when That Sockpuppet named Joey disrupted the list in 2017, 2018 and 2019 and put VY Canis Majoris at 2,100 solar radii even though as Lithopsian said was the worst possible result or value that you could get. Those estimates are now outdated and Newer estimates like the 1,420 solar radii estimate in 2012 have been produced. That Sockpuppet has already accepted Stephenson 2-18 as the largest star But still continues to put VY Canis Majoris at 2,100 solar radii. The aftermath of the Sockpuppet disrupting the list unfortunately led the Stars to be in an almost random way. Not wanting to have Inaccurate Values, We have a New list and A new Template to verify the Values.That is why some stars are not here because Their sizes have not been verified yet and we want the list to be accurate.--THE COLOSSAL GALAXY NAMED IC1101 (talk) 09:07, 24 July 2020 (UTC)

MDFC AD catalog

Currently this article has been subject to an edit war - I saw the MDFC estimates were removed in the middle of this. Since the table provides the distances from Bailer-Jones et. al. I will try and verify all of the stars in the list - unfortunately it's very big, so I've only verified ~30 stars. catalog here: (https://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=II/361/mdfc-v10)

There is a list (Sheet4) that I'm keeping count of my verifications and rejections - there's also a total list, but that list may not hold up to Wikipedia guidelines (notably WP:SYNTHESIS) Ardenau4 (talk) 17:17, 19 July 2020 (UTC)

Removed? Are you saying that the sizes were removed from the list? I don't see any major decrease in size (in the edit history of the list, the only major decrease in size was when Primefac replaced the original list with the new list. Could you please specify the date on which these sizes were removed?

Thanks!

PNSMurthy (talk) 08:10, 20 July 2020 (UTC)

I can't seem to find the original revision - I believe Lithsopian removed them because the size is not directly stated in the database - however I feel like it would be unfair to exclude results from a database specifically measuring the (angular) sizes of stars just because the sizes are not directly stated - the database incorporates distance from Bailer-Jones anyway so I don't think this is case of WP:SYNTHESIS. Ardenau4 (talk) 20:28, 20 July 2020 (UTC)

Hmf, okay. I'll see what the VizieR link shows.PNSMurthy (talk) 23:04, 20 July 2020 (UTC)

Just realized I forgot to include the spreadsheet I was talking about.

Ardenau4 (talk) 20:30, 20 July 2020 (UTC)

The spreadsheet appears to be based on an old version of the list. The list was completely replaced with the "new list" a week or two back. That shouldn't prevent stars with valid reliable references being added. Or some entries may have been removed for other reasons, such as a more reliable radius value being below the 700 R threshold. There is a history of all changes, but it may not be worth the effort of trying to match up to an old version. Lithopsian (talk) 14:09, 21 July 2020 (UTC)

What was Ardenau4 talking about when he mentioned you wiping a version of the list of the database?PNSMurthy (talk) 23:05, 21 July 2020 (UTC)

No idea. I'm the wrong person to ask really, since I'm not psychic. Lithopsian (talk) 14:42, 22 July 2020 (UTC)
What do you mean??? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 14:51, 22 July 2020 (UTC)
He means he doesn't know. Okay then, so you, Lithopsian, have not removed it. I don't think it was ever there -and if it was, the only people who could have removed it are Primefac, because he is the only admin who edits this list (at least regularly).PNSMurthy (talk) 02:56, 23 July 2020 (UTC)

Yep , he is the only admin that edits this list regularly... THE COLOSSAL GALAXY NAMED IC1101 (talk) 03:17, 23 July 2020 (UTC)

LOL, you didn't need to say that:)PNSMurthy (talk) 03:22, 23 July 2020 (UTC)

Um..... I saw your List of Largest stars and , Where did RMC 87F Go? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:19, 23 July 2020 (UTC)

I attempted to find a claim saying it’s not a red giant, but I couldn’t, so I scrapped it. And, that list is just my opinion and contains some sizes that might be considered slightly dubious.PNSMurthy (talk) 07:31, 23 July 2020 (UTC)

Also mine.I already exceeded 300 + edits, and made a list of Users whom I surpassed in terms of Edit Numbers. I have something to tell, Reply To the comment about SpaceImplorerExplorer and an IP User who does not like extreme numbers and how they should appreciate the extremities of the universe In #RX Telescopii. — Preceding unsigned comment added by THE COLOSSAL GALAXY NAMED IC1101 (talkcontribs) 08:41, 23 July 2020 (UTC)

Again, don't be so inflammatory. 300/18 gives roughly 17. That means you do 17 edits per day. Not impressed. I do 29 edits per day LOL.PNSMurthy (talk) 00:30, 24 July 2020 (UTC)

What I meant Is, for me, A new User Getting 300+ edits is for me Impressive. --THE COLOSSAL GALAXY NAMED IC1101 (talk) 09:18, 24 July 2020 (UTC)

IRAS 05280-6910 and VV Cep

There appear to be lower and more recent size estimates for these 2 stars than the sizes on this page (516 solar radii for VV Cep and 1,367 for IRAS). Check their pages. I haven't checked the sources myself but if those sizes are listed in the sources, should we consider using those sizes for this list instead of the current ones?JayKayXD (talk) 18:34, 7 July 2020 (UTC)

Take your pick, or there has been a proposal to show ranges in the table. Better yet, take a look at the articles. If the values are good enough for the starbox then I'd have thought they should be good enough for the list. Likewise, if they're not good enough then they should come out of the starbox. Lithopsian (talk) 20:37, 7 July 2020 (UTC)

I doubt the VV ceph estimate is correct. Countless estimates give over a thousand (including one giving exactly so much), and one only gives 516. Though I suppose this is just my opinion...PNSMurthy (talk) 05:30, 12 July 2020 (UTC)

I guess you could say the same thing about 972 for Mu Cep but people seem OK with that. Another recent estimate for VV Cep is now on the list at 1,000 solar radii which is more consistant with other estimates so I guess everyone's happy now :) .JayKayXD (talk) 21:19, 13 July 2020 (UTC)

Yep, the articles are in a mess too. Many don’t sight the latest and most accurate estimates. I had to clarify VV Ceph myself, just because it’s a relatively well known star, but am not going to bother to do the same for the other stars.PNSMurthy (talk) 02:14, 14 July 2020 (UTC)

Yep, I noticed that Many of the articles contradict what is seen on the list... I will take HV 888 for example. In its article is 1,300 solar radii, but here it is estimated to be 1,477 solar radii. What about the 1,788 solar radii estimate for WOH G64? THE COLOSSAL GALAXY NAMED IC1101 (talk) 04:38, 23 July 2020 (UTC)

The list should usually reflect what is in the starbox of any article about the star, as being the most representative radius. If they are different, either the list or the article should change. Lithopsian (talk) 13:55, 23 July 2020 (UTC)Where this isn't obvious, the talk page of each star may be a good place to discuss which radius value should have prominence and how that could be caveated in the body of the article. Then propagate it to the list. There is already a section on Talk:HV 888, which mentions a much larger radius calculated from a very large luminosity given in Groenewegen et al. (2018). Lithopsian (talk) 13:55, 23 July 2020 (UTC)

I believe the source was 1 degree off. I don't trust that article - though this is purely my opinion. I believe Sam Halls labelled the unidentified object on Quora 'WOH S64'.PNSMurthy (talk) 06:07, 23 July 2020 (UTC)

Ok, Pls respond to my reply at #RX Telescopii where we talk about SpaceImplorerExplorer who likes ranges with low values and an IP user who does not like extreme values and saying “Help me find a lower and reasonable value for these stars” And how they should appreciate the Extremities of the Universe. THE COLOSSAL GALAXY NAMED IC1101 (talk) 14:11, 23 July 2020 (UTC)

It looks like the 1,974 solar radii value for HV 888 was calculated from a Luminosity Larger than Stephenson 2-18's Luminosity ! If HV 888's size estimate is only 1,300,1,353 or 1,477 solar radii, Guess I will have to update my Sandbox then... Sam Halls will might have to update his own article. Hopefully He won't place Stephenson 2-18 at 1,630 solar radii and put it 2,150 solar radii instead. PNSMurthy, Why is HV 888's 1,974 solar radii estimate Cherrypicking , that is even worse than RW Cephei's cherrypicked value ????? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 09:29, 24 July 2020 (UTC)

1,260 R for IRAS 05280-6910

A radius of 1,260 R (1.26 × 10^3 R) for IRAS 05280-6910 is in the Marshall citation per Table 4 (pg 12)! And do you think it should be used since, the stars should be sorted by the smallest estimates (useless if the larger estimates is calculated from more accurate measurements) per talk but appearently this estimate may be old? 2A01:E0A:47A:F100:3DF3:EDFC:6831:BA1D (talk) 10:44, 3 May 2020 (UTC)

That's a pretty old paper (in astronomical research terms), with the radius based on a 1992 paper. It may well turn out to be a more reasonable radius than the one just published, but who are we to decide that? Lithopsian (talk) 16:39, 3 May 2020 (UTC)
I think we should use it since the stars are usually sorted by the smallest estimates per talk? 2A01:E0A:47A:F100:3DF3:EDFC:6831:BA1D (talk) 17:10, 3 May 2020 (UTC)
You can't just go back in history until you find something that puts the star where you want it in the list. A good criterion to use is whether you would have that value in the starbox of an article about the star. Perhaps you would. I wouldn't. The 2016 referenced value, however surprising, is based on far more reliable observations and methods than the 2004 Marshall paper. I would be looking for some particularly strong reason to use data from the older paper, except possibly as part of a more detailed history in the body of the article. Lithopsian (talk) 19:08, 3 May 2020 (UTC)
If you're looking for other papers about the star, why ignore Boyer et al. (2010) which gives a radius of 1,700 R?[1] Not entirely surprising since Matsura just adopted the temperature and luminosity values from Boyer, but this sort of consensus amongst astronomers is what we should be reflecting in Wikipedia.

References

  1. ^ Boyer, M. L.; Sargent, B.; Van Loon, J. Th.; Srinivasan, S.; Clayton, G. C.; Kemper, F.; Smith, L. J.; Matsuura, M.; Woods, Paul M.; Marengo, M.; Meixner, M.; Engelbracht, C.; Gordon, K. D.; Hony, S.; Indebetouw, R.; Misselt, K.; Okumura, K.; Panuzzo, P.; Riebel, D.; Roman-Duval, J.; Sauvage, M.; Sloan, G. C. (2010). "Cold dust in three massive evolved stars in the LMC". Astronomy and Astrophysics. 518: L142. arXiv:1005.5167. Bibcode:2010A&A...518L.142B. doi:10.1051/0004-6361/201014513.

Lithopsian, I have a question. Should The smaller estimate should be used even if the Larger Estimate is more accurate, making the larger estimate useless just like how the IP user said ???--THE COLOSSAL GALAXY NAMED IC1101 (talk) 09:34, 24 July 2020 (UTC)

Why is the talk page protected?

I understand the article being protected, but why the talk page? There's a person that the protection is preventing from asking a question about some data in the list. SevenSpheresCelestia (talk) 21:14, 27 April 2020 (UTC)

The person in question made some edits and was able to ask his question (see below), but I'd still appreciate a response here. SevenSpheresCelestia (talk) 20:55, 28 April 2020 (UTC)
The banner at the top of the page says that Primefac (talk · contribs) semi-protected the page at the start of last year for persistent sockpuppetry. Throughout 2018, the article and talk page had been disruptively edited multiple times. I haven't seen signs of that particular sockpuppet for a while - maybe they grew up? Lithopsian (talk) 20:13, 1 May 2020 (UTC)
Or maybe they couldn't create accounts fast enough to get through the semiprot. Either way, I see no issue in dropping protection; easy enough to restore if they come back. Primefac (talk) 20:50, 1 May 2020 (UTC)
Thanks for the answer, I was aware of that person's disruptive edits but not that they extended to the talk page. SevenSpheresCelestia (talk) 19:27, 3 May 2020 (UTC)

I know that Person, That person's name is Joey P. He is basically A fan of VY Canis Majoris, Even after a New Accurate Size was published, Which is the 1,420 solar radii Estimate, He still Puts VY Canis Majoris at 2,100 solar radii, despite It being As Lithopsian said, The worst possible Result you can Get of VY Canis Majoris's size! He refuted the Claim that UY Scuti Was the Largest star (I also refute the claim that UY Scuti was the largest because Stephenson 2-18's Estimate was Published In 2012, Which would mean that UY Scuti was Never the largest Star) It indicates that He can't Move on. The sign that He likes VY Canis Majoris' Old size of 2,100 solar radii is seen When he Disruptively Edit the List of largest stars. He created Multiple accounts, Thinking that He will get away with It. He has apparently had enough of the WP Community, He continues up to this day to put VY Canis Majoris at 2,100 solar radii, Despite Having accepted Stephenson 2-18 as the largest star. Joey,I support Your claim that UY Scuti was never the largest star, But you must accept the More Accurate and More Recent VY Canis Majoris estimate of 1,420 solar radii. --THE COLOSSAL GALAXY NAMED IC1101 (talk) 12:02, 26 July 2020 (UTC)

What is the definition of 'inaccurate' ?

In my quest for size, I have uncovered two stars above 2,500 solar radii. One of them is Alicante 8 S4 with a size of 2,698, and another is THA 34-26 with a size of roughly 2,750 (the former is in Negruezla et all, and the other is Statssun et all). I've refrained from adding these stars because of their extreme size, but should I add them, or are they 'inaccurate'?PNSMurthy (talk) 07:35, 7 July 2020 (UTC)

DO NOT ADD THEM. They are most likely inaccurate, their properties are unreasonable. I am getting tired of this conundrum ! Nussun 05, meanwhile has accepted THA 34-26 as the largest star, Not knowing that is inaccurate. WE SHALL STOP THIS ! --THE COLOSSAL GALAXY NAMED IC1101 (talk) 07:58, 7 July 2020 (UTC)

Okay...Anyone else?PNSMurthy (talk) 08:13, 7 July 2020 (UTC)

By the way, I saw your sandbox. The Red Supergiants in W1 aren't actually of that size, that's stictly W1-26. Read the 'RSGC's in...' section in this talk page started by me.PNSMurthy (talk) 08:16, 7 July 2020 (UTC)

Ok, I am going to edit it now. just don't add inaccurate sizes like Nussun 05 is doing.−−THE COLOSSAL GALAXY NAMED IC1101 (talk) 08:41, 7 July 2020 (UTC)

Like I have already told you, those sizes might be accurate, we don't know if they're inaccurate. PNSMurthy (talk) 08:50, 7 July 2020 (UTC)

Alicante 8 S4 = 2,698 R appears to be incorrect. Although I can't see a bolometric luminosity value in the text of Negueruala et al. (2010), the HR diagram shows a luminosity below 100,000 L. Please re-check your calculation and perhaps show the working here.
THA 34-26 = 2,753 R is determined using a Gaia DR2 parallax which has a margin of error larger than the parallax itself. I think that qualifies as inaccurate, but the radius is in that reference. Lithopsian (talk) 16:08, 7 July 2020 (UTC)

I feel I have to disagree, see table 2 - the HR Diagram is for the positions of the stars, not the parameters. The table shows the properties of the stars, and an apparent magnitude of -10.4 and a temperature of 3,650 (at maximum) gives 2,698 R. PNSMurthy (talk) 01:32, 8 July 2020 (UTC)

Where are you getting these numbers from? I'm only aware of one paper by Neguerela giving properties for this star, and in table 2 it says temperature 3,400±150 K and MK = −10.3. And how are you using an apparent magnitude to get a radius? You appear to have treated -10.4 as a bolometric absolute magnitude, which would mean a luminosity over a million L, dubious even if that's what the paper said. Lithopsian (talk) 14:53, 8 July 2020 (UTC)

My point exactly, how can a star be so big? Should it be added?PNSMurthy (talk) 04:47, 9 July 2020 (UTC)

It can't be added because the calculation is wrong. And the values used for the calculation don't even appear to be in the paper. Whether we think a star can be that big isn't really relevant. Lithopsian (talk) 14:00, 9 July 2020 (UTC)
Hmm, I seem to have found a diagram showing Lbol. I'll just work with that. Never mind, I see my mistake Lithopsian.PNSMurthy (talk) 01:21, 10 July 2020 (UTC)

We almost had a star that has an estimate larger than Stephenson 2-18... Shall we discuss about RHI84 10-63? Lithopsian, Is it accurate since I saw that Nussun05 has found a new list of star sizes, Which is TESS Input Catalog V8. 3 of which are or might be larger than Stephenson 2-18 but one of them Was proven Inaccurate . They are THA 34-26, RH184 10-683 and V538 Carinae. Their size estimates are: For THA 34-26: 2,753 solar radii (Ruled out) For RH184 10-683: 2,296 solar radii (Possibly Inaccurate) For V538 Carinae: 2,264 solar radii (Likely Inaccurate). --THE COLOSSAL GALAXY NAMED IC1101 (talk) 12:43, 24 July 2020 (UTC)

I see no catalog Nussun05 has found.PNSMurthy (talk) 01:08, 25 July 2020 (UTC)

Oh... I think she has a youtube channel THE COLOSSAL GALAXY NAMED IC1101 (talk) 04:22, 26 July 2020 (UTC)

Alright, what's its name.PNSMurthy (talk) 05:09, 26 July 2020 (UTC)

PZ Cassiopeia Productions THE COLOSSAL GALAXY NAMED IC1101 (talk) 10:21, 26 July 2020 (UTC)

Oh, yes, Nussun05 informed me of that.PNSMurthy (talk) 23:10, 26 July 2020 (UTC)

Should Everything have period at the end?

When The list says "Located in the Small Magellanic Cloud " for example, It does not have period. Should I add period? --THE COLOSSAL GALAXY NAMED IC1101 (talk) 05:05, 27 July 2020 (UTC)

Certainly, if you wish.PNSMurthy (talk) 07:39, 27 July 2020 (UTC)

I made a few updates.

So I updated the list because a few stars have outdated sizes, I might not have gotten all of them, so I would appreciate a little help with this. Thanks. Nussun05 (talk) 19:09, 31 July 2020 (UTC)

Sure.PNSMurthy (talk) 01:39, 1 August 2020 (UTC)

The new feature

So I tried to implement the feature from the list of most luminous stars but idk how to do it on the List of largest row stars Nussun05 (talk) 07:16, 1 August 2020 (UTC)

Okay, why not ask @Primefac: to expand the template to accommodate this?PNSMurthy (talk) 07:34, 1 August 2020 (UTC)
I have removed the future until we understand how to implement it (if we ever do).PNSMurthy (talk) 02:15, 2 August 2020 (UTC)
I'm mostly going through my pings (and I haven't had a chance to look at the hundreds of recent edits to this article or talk) but what "feature" is being discussed? Specificity helps when the pinged editor has no idea what's going on! Primefac (talk) 02:22, 2 August 2020 (UTC)
@Primefac: The feature that has been implemented in the list of most luminous starts article - which shows which galaxy a star belongs to.PNSMurthy (talk) 06:28, 2 August 2020 (UTC)

Where did all the templates go?

There is a template now for consistency and transparency when we do our own calculations of the radius from an effective temperature and bolometric luminosity. This seems to be one of the few reasons for the new list and the subsequent update to this list, and yet a number of stars appear not to be using it. I'm tempted to remove, let's say comment out, any star that quotes a reference which does not actually contain a hard-coded radius value. I've tagged them for now, at least the ones I spotted so far. Is there no template for us calculating a radius from an angular diameter and distance? There are citations with multiple angular diameters and it isn't always clear what is happening. Lithopsian (talk) 20:30, 15 July 2020 (UTC)

Templates? I thought that if the luminosity, temperature or angular diameter was, well reliable, and didn’t contain any below 3,000K temperatures, it would do. I didn’t bother to change the actual table, partially because there were too many to do it for. There were, as far as I had seen, not extremely cool temperatures or extremely high luminosities. I thought, that if the authors stated accurate parameters, it could be used. And it’s rare when authors actually state solar radius. As far as I’ve seen, only Levesque et all and a few other papers state the actual radius’s. the rest are just luminosities or absolute bolometric magnitude alongside temperature. Do you really need to 1.) Verify articles only with actual solar radius, and 2.) use templates to catalogue them?PNSMurthy (talk) 02:14, 16 July 2020 (UTC)
So why do we have a template? Yes, its uncommon for authors to actually state a radius, even in cases where they know the radius. That's the whole point. In most cases we are quoting a paper that doesn't contain the value it is supposed to confirm. That is very flaky ground for Wikipedia, and even if the paper contains values that can unambiguously be used to calculate the radius, most people will not be able to look at two large numbers (or logarithms of large numbers) and come up with the radius in their head to check. The template also ensures that the calculation is done accurately, or at least consistently, so that there are no mistakes in the arithmetic to confuse things further. Lithopsian (talk) 15:43, 16 July 2020 (UTC)
Sure (though i'm not going to be the one converting those tables - at least for a while). And, just as a point, most people don’t actually go and scour the refs. Even if they do, most of the stats are on Vizier, and pretty much all the people who just see this page and don’t edit it, don’t go scouring on Vizier. Only the editors of the list, me included, do that. Everyone else, even other Wikipedia editors, just go with our word. I know this, because, for a long while, I was doing that myself.PNSMurthy (talk) 01:05, 17 July 2020 (UTC)
PNS, it shouldn't matter whether "people don’t actually go and scour the refs" or if they do, we need to be accurate in our reporting of what is in the sources. Lithopsian, other than having two-points of verification or some sort of in-code indicator that a value has been checked by at least two people, I'm not sure how we can keep from constantly going back over the templated/non-templated values for accuracy (though to be honest, I've found more incorrect "calculated" values where the logL or L wasn't even given in the article). It's like we need a live article, a working subpage, and a "yes we've really checked this" subpage. Primefac (talk) 15:41, 2 August 2020 (UTC)
I'm now commenting out rows that containing radius values not in the reference, and that do not use the template for calculating a radius from other values actually in the reference. Use it or lose it. Lithopsian (talk) 20:10, 19 July 2020 (UTC)
SurePNSMurthy (talk) 23:09, 20 July 2020 (UTC)

I can't don that though...I'm quite busy at the moment. Would someone else mind doing it? Once I'm free again (in a couple of days or so) I'll start working on the new list again.PNSMurthy (talk) 02:36, 22 July 2020 (UTC)

Split by location

Given the attempt at putting in a "new feature" without discussion, I guess we should discuss it. Yes or no question: should we split the table to have "galactic" and "extragalactic" stars? There's already a section about the extragalactics, does it make sense to split them? If the consensus here is "no", should we somehow indicate (or than in the notes section as is current practice) that they are extragalactic? Keep in mind that such information should not be conveyed purely by colour, as it is bad practice bordering on an ACCESS violation. Primefac (talk) 15:46, 2 August 2020 (UTC)

I think we should make a full list, and lists of largest by galaxy separately. Nussun05 (talk) 19:05, 2 August 2020 (UTC)
I don't think there's much reason to have all of the information on the page twice. Primefac (talk) 19:07, 2 August 2020 (UTC)
We could make the non-Milky Way stars only. GurrenLagannTSS (talk) 20:58, 2 August 2020 (UTC)
Why? Are stars outside our galaxy not large? Primefac (talk) 21:19, 2 August 2020 (UTC)
No, its because (in my opinion) most of the large stars are in the Milky Way (and on its satellite galaxies), so doing the lists for just the galaxies beyond the Milky Way Subgroup could work. GurrenLagannTSS (talk) 22:22, 2 August 2020 (UTC)
I think the best is that rows should be coloured but the "provided for reference" values should be coloured back in Wheat. 2A01:E0A:47A:F100:7D65:53AD:74A5:2548 (talk) 21:05, 2 August 2020 (UTC)
Um... that's not really what we're asking here. If you want to change colour schemes, start a new section? Primefac (talk) 21:19, 2 August 2020 (UTC)
The point is, there are waaaaaaaaaaaaaaaaaaaay to many stars outside the Milky Way in this list. We need to be able to differentiate them, don't we?PNSMurthy (talk) 22:33, 2 August 2020 (UTC)
That's why I'm asking the question. Primefac (talk) 22:57, 2 August 2020 (UTC)
So, lets implement the addon from the list of most luminous stars.PNSMurthy (talk) 23:35, 2 August 2020 (UTC)
No one is really giving their opinion here. If you are in favor or against this new addon, please explicitly say so. That's the whole point of this talk page!PNSMurthy (talk) 23:36, 2 August 2020 (UTC)