Talk:Rigel/Archive 2

Do you think there is enough coverage now? Time to polish? Lithopsian (talk) 21:07, 1 February 2019 (UTC)

This article still has more than a few dozen gross errors, which need to be corrected. (I've just correct the variable star designation that appears in the GCVS5.) It remains below GA standards based on poorly sourced or over used references for cites e.g. Kaler and Schaff. John Herschel first discovered in 1839 that Betelgeuse was sometimes brighter than Rigel. Webb (and several others) have said in the 19th Century "…has speculated that maybe it was during a rare period where it was outshone by Betelgeuse resulted in the latter star being Alpha and Rigel Beta Orionis." Kaler just repeated it. It is also fits uncontroversial knowledge as stated in WP:SCG.

I have removed the tag - Herschel (1840) doesn't speculate on the Bayer designations. I don't know the Webb citation. Just because Kaler mentions it does not mean he came up with the idea. Hence the statement and source are true. If you find an older source speculating on the same issue you are welcome to add it. If you can't then it stands as the best available reference. In any case it doesn't warrant a ^{[dubious – discuss]} tag, which is missing the point. Cas Liber (talk · contribs) 12:36, 3 February 2019 (UTC)

As for the 2nd paragraph of 'Nomenclature' it verbosely/garrulously says:

"In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[22] to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016[23] included a table of the first two batches of names approved by the WGSN, which included Rigel for the star β Orionis A. It is now so entered in the IAU Catalog of Star Names.[24]"

Simply write:

"In 2016, Rigel or β Orionis A. was entered in the IAU Catalog of Star Names.[24]"

Here GA requires "They are well written, contain factually accurate and verifiable information." This article presently fails on all three counts!! Arianewiki1 (talk) 02:12, 2 February 2019 (UTC)

What are you saying is the original reference/person for proposing that the Bayer designation occurred at a (rare) time when Betelgeuse outshone Rigel? Cas Liber (talk · contribs) 02:39, 2 February 2019 (UTC)

PS:Text can't be "garrulous" as it is written not loudly spoken - the word you (presumably) want is verbose. Also, feel free to list specific errors as you find them. Cas Liber (talk · contribs) 02:40, 2 February 2019 (UTC)

"garrulous" can mean long-winded or wordy BTW. Its antonym is "concise".

I note the stated magnitudes are mostly wrong, especially as the Guinan et al. (Ref 4) is quoting the range of 0.05 to 0.18 from another unnamed source. (They didn't measure it BTW) . Even Moravveji, et al. (2012) Vmag of ~0.12 was only derived over 27.7 days. Its range appears as 0.17p-0.22p in GCVS (2009), from 0.17-0.22 Hpmag (1991) in a period of 2.07 days, and 0.03:V-0.30:V NVS (1981). A better mean visual mag is +0.08 from uvbyβ results (no extinction problems) from Hauck (1997) (as uvby98 100034085) than +0.13 from Ducati (2002) "Catalogue of Stellar Photometry in Johnson's 11-color system.", which has questionable extinction especially with a nearby reflection nebula. Arianewiki1 (talk) 04:30, 2 February 2019 (UTC)

Simple - we can put in both - can you write in plain English how the two results are derived? Cas Liber (talk · contribs) 04:56, 2 February 2019 (UTC)

Guinan got their results from their own study in 1985 of observation over 18 nights. I have expanded how they got that. Cas Liber (talk · contribs) 19:54, 4 February 2019 (UTC)

Its tricky. Very few reliable sources publish a range of variability in the V filter. Guinan does, although is a bit lax about explaining where it came from. He's done the photometry, but it isn't clear which photometry was used or whether it was just a general guess from literature values. The NSV (sic) catalogue is a possible alternative. The results are just a crude min/max of extreme values from the literature, not necessarily consistent with eachother, but could be considered comprehensive. Difficult to cite though, because they've been removed from the latest versions of the online tables. As for the "mean" magnitude, Simbad lists Ducati and that's good enough for most people. +0.12 was in Simbad for a long time, is in many catalogues such as the Bright Star Catalogue, and is still widely quoted. Quite how much of a mean it really is is open for discussion. Hauck is definitely a mean, of one value from the 1970s, so we should ignore that. The GCPD is a comprehensive catalogue of photometry and they publish a weighted mean in the UBV system of +0.138 (in GCPD2), as well as showing all the underlying published values. Hipparcos doesn't publish V magnitudes, but their Hp results suggest a considerably fainter range. The Tycho Vt magnitude is close to V and can be converted to within a few hundredths, suggesting a V magnitude of +0.28. Older photovisual magnitudes that should be close to the V system give results around +0.30, for example the HD catalogue at +0.34. I can't find any reliable sources discussing these possible discrepancies, for example as a secular change in brightness, larger range in the past, inaccuracies in some older data, or simply very erratic variations with rare bright and faint periods. Some (most, to be honest) of these magnitudes are for the combined ABC system, but the difference from A alone is tiny. I'm not sure we need to change anything in the starbox, except possible using the NSV numbers for the variable range. Discussion in the text would be difficult because there are no sources to cite, other than throwing out a whole slew of numbers which we shouldn't read too much into ourselves. Lithopsian (talk) 21:50, 4 February 2019 (UTC)

The "In modern culture" section reads:

See also: Rigel in fiction

The MS Rigel was originally a Norwegian ship, built in Copenhagen in 1924. It was requisitioned by the Germans during the World War II and sunk in 1944 while being used to transport prisoners of war.^[1] Two US Navy ships have borne the name USS Rigel.

The SSM-N-6 Rigel was a cruise missile program for the US Navy that was cancelled in 1953 before reaching deployment.^[2]

The Rigel Skerries are a chain of small islands in Antarctica, renamed after originally being called Utskjera. They were given their current name as Rigel was used as an astrofix.^[3] Mount Rigel, also in Antarctica, is also named the star.^[4]

None of these are actually about Rigel. They're about other things that just happen to be named "Rigel". The section should be renamed, reorganized or moved to a disambiguation page. JIP | Talk 10:39, 28 March 2019 (UTC)

Err, they were all named after the star. I get your point though and am pondering. Cas Liber (talk · contribs) 10:59, 28 March 2019 (UTC)

Yes, they are all named after the star, but none of them are the star. Therefore this section is more like "Things named after Rigel in modern culture". JIP | Talk 11:51, 28 March 2019 (UTC)

A section titled some variant of "Popular culture" is a common problem in Wikipedia. These sections are like kudzu, every time you try to trim them back, they get more entries added. The general (exhausted) attitude I've seen is to mostly ignore those sections. Tarl N. (discuss) 02:54, 29 March 2019 (UTC)

I have added this recent edit to the article page which compromises between adaptation of the non-stanadard names and the popular names and includes two adequate cites for both sources. (The article now splits this into two paragraphs.) The figure within this page from "New Concepts of Binary/Multiple Star Designation" here shows the unambiguous usage of the wider used system used for multiple and double stars.

I think the failure is the arguments previously to this has been argued using either "A or B" for designations (The premise of the RfC, where the argument should have been "A and/or B". I agree that using Rigel A (or its variants) should be widely used throughout the article if only because it makes the article easier to read. However, regardless of the rarity of usage, if both methods are still used, they must be therefore both credible in their usage.

If editors do still feel strong objections still, then the double star designations could be perhaps added as an additional endnote.

If an editor wants to delete this text again, before doing so, please answer: "If Rigel A, etc. are the 'unofficial' IAU designations, then what are the 'official' IAU designations for the components then?"

Note: My last response in the RfC here reasonably explains how much they are used. (as Cas Liber asked "Just to show the rest of us how commonly they are used.". I now have. Arianewiki1 (talk) 02:28, 31 March 2019 (UTC)

Okay, the official designation is Rigel for Rigel A and the other obscure names that you've listed. The nomenclature section now accurately lists the names except for some bit that I corrected. The preference of other parties is to use Beta Orionis BCD (presumably) given Rigel's restriction to the most luminous component. I am happy with that. Cas Liber (talk · contribs) 11:48, 31 March 2019 (UTC)

I have reversed your edit because Beta Orionis for the B, C and D stars are not mentioned in the reference, as already pointed out by others. The reference has to be in the paragraph, as the IAU decision is on single stars and not multiple.double stars. There is no references that I can find no official statement define that the case. B, C and D are defined by two sources that use it in the cites. i.e. Kaler. Also please strike out the word "obscure" above, and they are in fact the official nomenclature, as "New Concepts of Binary/Multiple Star Designation" shows. Also, your contributions were not the only compromises made here. Arianewiki1 (talk) 23:20, 31 March 2019 (UTC)

@Attic Salt: I have just removed the unnecessary reference altogether, as it does not state this but the cite of Garfinkle and Kalrrigel does. This is still factual without it, and it removes any ambiguity or continuing debate. Arianewiki1 (talk) 23:29, 31 March 2019 (UTC)

After reading these edits again, I have reconsidered this last edit. Casliber (incorrectly) wrote that the reference "refers to Rigel BCD not A" when the made an edit, but the source does refer to A. e.g. pg.5 "…it was decided to attribute proper names to individual stars rather than entire multiple systems. For example, the name Fomalhaut specifically refers to the bright A component of a 3-star system." The reference implies e.g. pg..5 "The informal names often attributed to other components in a physical multiple (e.g., “Fomalhaut B”) are treated as unofficial,…" so Rigel B can be correct but Rigel C and Rigel D cannot, because we do not know if they are physically attached to Rigel A. I interpret that the reference cite should be attached to Rigel B NOT Rigel C or D. Their statement is therefore not implicitly true.

Saying: "...preference of other parties is to use Beta Orionis BCD." had little to do with the IAU publications, which proceeds the publication date of the IAU decision.

Furthermore, this same reference says " In the IAU CSN, the components are clearly identified via their WDS identifiers…", which verifies the double/multiple star designations in this whole paragraph. Thanks for pointing out these finer points. Arianewiki1 (talk) 01:44, 1 April 2019 (UTC)

Are you deliberately misreading this?? It says on page 5, "The informal names often attributed to other components in a physical multiple (e.g., “Fomalhaut B”) are treated as unofficial, and not included in the IAU Catalogue of Star Names†." with the footnote adding "As these useful nicknames with the form [proper name] [letter component] often appear in the literature, many appear in the SIMBAD database." - this clearly refers to any component of the Rigel system EXCEPT Rigel/Rigel A. Are you so set on your own opinion? How can you possibly read this any other way?? Cas Liber (talk · contribs) 10:33, 1 April 2019 (UTC)

Look. The usage is for components that are physically attached in a multiple system. Rigel B seems certainly attached, but the C and D stars are yet to be verified. i.e. they could be optical doubles. (this has been pointed out in the RfC by others in the discussions above.) I don't think the text necessarily supports Rigel C and Rigel D at all, and I think you might be over reading this. Rigel C and Rigel D is hardly 'often' and the usage does not extend to SIMBAD. Also the statement "...the name Fomalhaut specifically refers to the bright A component" just verifies to name 'Formalhaut A' and 'Rigel A' and implies the name 'Formalhaut' or 'Rigel.' Either term is OK. Uncontroversial I'd think.

Again. The IAU decision is on single stars and not multiple/double stars.

Again. If Rigel A, etc. are the 'unofficial' IAU designations, then what are the 'official' IAU designations for the components then? Arianewiki1 (talk) 23:15, 1 April 2019 (UTC)

Also I won't strike out "obscure" - many official names are obscure Canis lupus is obscure to may dog owners, "134340 Pluto" is obscure. So are all the WDS designations. Most journals use other designations. Cas Liber (talk · contribs) 10:38, 1 April 2019 (UTC) is

Continuing to state these are "obscure" is being done only for emotive reasons and is not based on fact. Either cite a source that says the WDS nomenclature are 'obscure' or stop saying it. As you cannot seem to answer the simple question: "If Rigel A, etc. are the 'unofficial' IAU designations, then what are the 'official' IAU designations for the components then?", your contentions cannot be taken seriously. Arianewiki1 (talk) 23:25, 1 April 2019 (UTC)

The IAU says the official name of Rigel A is Rigel. I don't know why you did this as it is obviously talking about other components that are not the bright ones as the example is FOMALHAUT B. Cas Liber (talk · contribs) 10:06, 2 April 2019 (UTC)

Also this is why the sentence uses the word such as I know the source is not referring specifically to Rigel BCD (or A for that matter) but all components where they are referred to by a common name followed by letter. Cas Liber (talk · contribs) 10:10, 2 April 2019 (UTC)

By for the designation to be valid, it has to be physically attached. Star C and D are not. As Lithopsian rightly says: "Using the term Rigel A (or B) might be justified in isolated cases where we need to be explicit about distinguishing components, but where we also want to use the Wikipedia article title…" & "Im not comfortable with Rigel B, Rigel C, etc. I've used them in the past, but their borderline status has been completely stamped on by the IAU." & "β Orionis B strictly only refers to the brighter of the close visual pair, so we need to be clear when we're referring to individual components" (therefore discounting C, Ba and Bb), Hence the IAU single star source was never meant to be used to as you are suggesting. We've agreed that using these terms in the article is for simplicity but extending this to some IAU 'stamp of approval' is quite unjustified.

Also, do not again remove this tag until you have consensus to do so. "Your" view here doesn't override other's objections. Removing this tag does not allow other editors to know there might be a dispute with verification Also saying "remove incorrect tag (again) see talk" is unfair because this tag has been only added once. Arianewiki1 (talk) 23:04, 2 April 2019 (UTC)

It is not just my view as OTHER SOURCES DO CALL THEM RIGEL C AND D. So it is your OR by selectively discounting the other sources. Cas Liber (talk · contribs) 23:25, 2 April 2019 (UTC)

Ridiculous argument, as the article sentence "Rigel's companions for simplicity are abbreviated as Rigel B,[21], C, and D.[25][22] " immediately before this gives two references for the usage (Garfinkle and Kalerrigel). (being cites [25][22].) The tag I've added ONLY applies to statement " The IAU describes such names as "useful nicknames" that are "unofficial"." It may apply to Rigel and and Rigel B, but as C and D components are not known as a physical system, the terms are not applicable. The IAU reference does not say what you allege. Removing the tag means this point cannot be investigated by other users in gaining consensus. You are dictating an opinion on a tag without any gained consensus. (Lithopsian in the quotes above seems to agree with my POV.)

So far I have attempted to try and accommodate your POV, which the most relevant is this, which you reverted by removing my comment "(as used in this article)" which shows your allegation is quite false. Even this compromise associated with Rigel B and leaving the text you've removed.

Yet the worst thing here is your continued refusal to answer this question (now five times) "If Rigel A, etc. are the 'unofficial' IAU designations, then what are the 'official' IAU designations for the components then?"

Either replaced the tag or this issue will dramatically escalate. Arianewiki1 (talk) 01:20, 3 April 2019 (UTC)

The offical names are "Rigel" for the brightest component (as you well know). The source states: "In the IAU CSN, the components are clearly identified via their WDS identifiers" (as you well know). I have said this before, so don't lie or exaggerate by claiming you've asked repeatedly and not been answered. Cas Liber (talk · contribs) 02:37, 3 April 2019 (UTC)

Good. So much happier now. My simple search of this page finds I've asked this five times, without you directly answering it. It is a lie nor am Iexaggerating the problem. Crucially, I'd do now think that your interpretation then is that the WDS identifiers are then superior designation than the single IAU star designation? (Your 'obscure' designation now seems contradictory.) It is a pivotal distinction. It also infers that WDS designation should be used, but for simplicity of the article using Rigel A to D is a reasonable compromise. However, the IAU 'single star' article infers a physical association to qualify as these 'unofficial' designations, C and D don't count. This is the second contradiction.

Clearly the usage is confusing between the two IAU sources. (It isn't an issue between wikipedia editors, but the IAU itself.) At least this supports the text of the WDS designation and Lithopsian's recent revert discussed in the next thread. Arianewiki1 (talk) 05:01, 3 April 2019 (UTC)

Okay, let's ask other people whether a "failed verification tag" is needed here...@Lithopsian, Attic Salt, Sbznpoe, AhmadLX, Tarl N., and Rursus:. PS: This is just about the use in that sentence. Happy to change all the rest of the article to Beta Orionis BCD etc. or whatever we decide after. Cas Liber (talk · contribs) 02:37, 3 April 2019 (UTC)

This is in reference to The IAU describes such names as "useful nicknames" that are "unofficial".^{[failed verification]}? I don't know what's unverified about it, section 2.2 of the cited IAU WGSN reference describes them as unofficial and in a footnote further characterizes them as nicknames. Certainly at a first glance, the "not in citation given " seems unwarranted. As for potentially not being in the same physical system (visual binary only), that hasn't stopped past designations of associations. Tarl N. (discuss) 04:03, 3 April 2019 (UTC)

I will comment - references earlier than about 2016 won't follow the IAUs current convention of the proper name applying only to the primary. Looking through my home library of astronomy books dating back to the 1970s, every single reference I could find to that white dwarf in orbit around Sirius, called it "Sirius B". And it was referenced as such in an Astrophysics course I took last year, where the professor was caught unawares that the IAU now considers the name to refer to only the primary. So we're on the bleeding edge of change where we might consider WP:COMMONNAME rather than official names. Tarl N. (discuss) 05:02, 3 April 2019 (UTC)

I'm no friend of IAU who very often violate sound philosophical and linguistic, principles and cannot produce a sound definition of a planet. IAU erect principles for star naming, then accept random star names by an international contest, which violates tradition and how the older star names emerged. I get the impression that they believe they are in power, and can do anything they want. Like kings. Of their "guide lines", only the following is sound: "Names that preserve world heritage (astronomical heritage, cultural heritage, and natural heritage) are strongly encouraged. Common and cultural star names are to be preferred over new names to preserve continuity and recognize astronomical heritage." Their other "guide lines" are bunk, and if a star had a name in the past, it has the name now. Wikipedia does not have IAU guide lines as a rule, nor a guide line. If astronomers seldom use Helvetios for 51 Pegasi, then the name is neither traditional, nor commonly used, it is just a immature whim.

One of the most untraditional of the ideas conceived by IAU is that only the brightest star in the star system had a name. It is not only untraditional, it is very awkward. If Rigel B and C was used in the past, then Rigel B and C was used in the past. We do not abide by IAU:s rules, we abide with facts. Rursus dixit. (^mbork³!) 07:18, 3 April 2019 (UTC)

I agree that decision will ultimately cause more problems than it solves. Still think it deserves mentioning, if we're going to mention the IAU naming decisions at all. Then we can ignore it, if that is what we think reflects the real world most accurately. Lithopsian (talk) 16:45, 3 April 2019 (UTC)

In reference to names like Star A, B or C, and the sentence in the article: "The IAU describes such names as "useful nicknames" that are "unofficial".[21]" I confirm that the cited source for the IAU description does indeed describe such names as "useful nicknames" that are "unofficial". Attic Salt (talk) 12:50, 3 April 2019 (UTC)

I don't see any problem quoting what the source says, since it is a reliable source in this context. To be certain we're all discussing the same thing, the referenced document states at the bottom of page 5 "The informal names often attributed to other components in a physical multiple (e.g., “Fomalhaut B”) are treated as unofficial, and not included in the IAU Catalogue of Star Names†.". The dagger indicates a footnote that states "As these useful nicknames with the form [proper name] [letter component] often appear in the literature, many appear in the SIMBAD database." So it doesn't seem out of line to describe them as "useful nicknames" that are "unofficial" in the IAU's opinion. Lithopsian (talk) 16:45, 3 April 2019 (UTC)

^{[not in citation given]} is certainly not true here. AhmadLX-)¯\_(ツ)_/¯) 19:28, 3 April 2019 (UTC)

@AhmadLX: Appreciate the comment, however, the document is more explicit than that, It only applies to established physically attached components.

Again. The reference implies e.g. pg..5 "The informal names often attributed to other components in a physical multiple (e.g., “Fomalhaut B”) are treated as unofficial,…" so Rigel B can be correct but Rigel C and Rigel D cannot, because we do not know if they are physically attached to Rigel A. It is reasonable to interpret that the reference cite should be attached to Rigel B NOT Rigel C or D. What interests the IAU is to associate named bright stars with real system components, including exoplanets. .eg. A hypothetical Rigel b.Arianewiki1 (talk) 21:46, 3 April 2019 (UTC)

Again, they are not definitely not attached and you are deliberately ignoring that that is what they are (informally) called. Cas Liber (talk · contribs) 01:22, 4 April 2019 (UTC)

Bingo!. "If a group of four or more stars are physically close and gravitationally bound, it is a physical multiple star and should be placed under the subcategory Multiple star systems." If "they are not definitely not attached" then they are not part of a "physical multiple." Ergo. The informal names often attributed to other components... are not treated as unofficial as they don't even exist under this IAU scheme of names of single stars. Arianewiki1 (talk) 03:49, 4 April 2019 (UTC)

We have nothing in the article that says that C isn't a member, and D is equivocal. We go on sources and they are discussed as (definite/possible) members of the system. We need to add material from a reliable source that doubts C's membership of the system. But still, they are still popularly called (Rigel) C and D. You can't change that. Cas Liber (talk · contribs) 04:19, 4 April 2019 (UTC)

Correction. The source of ] "If a group of four or more stars are physically close and gravitationally bound, it is a physical multiple star and should be placed under the subcategory Multiple star systems." is here. (not written by me.)

As for: "But still, they are still popularly called (Rigel) C and D. " No one denies that (I've said it several times), BUT, the cited IAU source doesn't verify that as fact. You've already got two cites that use such designation, and for the usage through out the article is accepted by me (and seemingly everyone else. From your previous statements the options for your arguments are rapidly narrowing. Now stating in desperation that "We have nothing in the article that says that C isn't a member, and D is equivocal." Yet another ill-informed diversion. OK. Prove that this is true. (Please know I'm an expert on this subject, published on the subject, ) Plainly the cited source does not say what you think, Arianewiki1 (talk) 07:57, 4 April 2019 (UTC)

We have nothing in the article that casts doubt on C's membership of the multiple system. I just tried looking on SIMBAD. If you know a paper on this, please add. Cas Liber (talk · contribs) 13:33, 4 April 2019 (UTC)

Simply, as previously stated, Rigel B usage means the three components Ba, Bb, C. The reason why these stars are combined is they are essentially unresolved by visual means. In SIMBAD, you can search for Rigel B, finding the combined star. Historical usage appears in reference Moravveji et al. (2012) "It is a member of a multiple star system where its companion, Rigel B, is a spectroscopic binary about 9.5′′distant)."

"Rigel C" does appear in SIMBAD, whose only usage seems to be in 1991 is the popular magazine 'Astronomy' - hardly a reliable source - and clearly not used by professional literature. I know of no other professional paper, whose only formal usage I know is BU 555 BC. Yet when searching in SIMBAD out to 4 arcmin finds three objects. Rigel BC is not used. Rigel D certainly doesn't apply.

As for: "We have nothing in the article that casts doubt on C's membership of the multiple system." It is part of a multiple system, but we don't know if it is a part of the physical multiple system.

I'd think, Rigel B has enough support to 'official' use, but the usage of the rest is dubious at best.

The article sentence of:

• "For simplicity, Rigel's companions can be designated as Rigel B,[21], C, and D;[25][22] the IAU describes such names as "useful nicknames" that are "unofficial".[21]" should be:
• "For simplicity, Rigel's companions can be unofficially designated as Rigel B[21], though Rigel C and Rigel D usage[25][22] has not been commonly adopted or promoted."

A fair enough compromise. 23:29, 4 April 2019 (UTC)

Disagree. An orbital period has been predicted for Rigel BC for starters. Find another article that discounts that would be a good starting point. I recall the original Burnham article calls it BC. will look up the ref. Cas Liber (talk · contribs) 23:45, 4 April 2019 (UTC)

Oh dear. Round and round in circles and now desperately clutching at straws. (Read the section below. 'Unhelpful edits on Rigel's Nomenclature' Irrelevant.') Rigel B comprises of Ba,Bb and Rigel C. Rigel B is already sufficient. Some predicted orbital period does not necessarily mean it is attached because the the motion has been only 25 degrees in PA and the separation has reduced by 0.2 arcsec. There is no evidence of orbital motion so it is an assumption. If an orbit had been calculated, then where is it? Again. Component C (BU 555BC) is part of a multiple system, but we don't know if it is a part of the physical multiple system. Saying there is a Rigel BC or Rigel C with IAU recognition is unsupported, while the official name for the system is BU 555BC, but using BC alone might be acceptable but Rigel BC is neither used nor remotely supported. Burnham says "The BC pair" and "Rigel C" isn't mentioned. (pg.1299-1301). Saying that "Often referred to as Rigel BC" just isn't true. (When I placed the official double star designation in brackets it was collectively removed by reverting!)

As for "Find another article that discounts that would be a good starting point."I've already told you.: "I know of no other professional paper, whose only formal usage I know is BU 555 BC. " So sorry. No. You think it true then the onus of proof is yours not mine , as per burden. Arianewiki1 (talk) 02:26, 5 April 2019 (UTC)

Do you even read what you write? Obviously if an orbital period exists then someone somewhere has examined and calculated one. The burden needs to be on someone commenting that the star might not be a part of the system. Cas Liber (talk · contribs) 02:56, 5 April 2019 (UTC)

I have. No orbit exists. A possible period can be estimated simply by estimating the distance and apparent separation. It has to be proven that the star have similar proper motions and lies at the same distance. An orbit has to have measures to draw out the orbit and calculate the orbital elements.The 6th Orbit catalogue, for example, does not have an orbit, and there are no sources that say this. None. Arianewiki1 (talk) 04:08, 5 April 2019 (UTC)

This continued circular debate now has to end as we have reached the level of unproductive minutia. The quickest solution is logically to write the questioned article sentence from:

• "For simplicity, Rigel's companions can be designated as Rigel B,[21], C, and D;[25][22] the IAU describes such names as "useful nicknames" that are "unofficial".[21]"

and changed to:

• "For simplicity, Rigel's companions can be unofficially designated as Rigel B[21], though Rigel C and Rigel D usage[25][22] has not been commonly adopted or promoted."

A fair enough compromise, eliminating interpretation of the IAU sources without arguing usage from references [25][22]. Arianewiki1 (talk) 02:42, 5 April 2019 (UTC)

I just want to point out that several publications concerned with double stars refer to "Rigel BC":

http://adsabs.harvard.edu/full/1947LicOB..19..175J http://adsabs.harvard.edu/full/1948LicOB..20..115M http://adsabs.harvard.edu/full/1954AJ.....59..388M http://adsabs.harvard.edu/full/1941PUPFA...6b...1W

Attic Salt (talk) 03:38, 5 April 2019 (UTC)

Umm… So what. These are being used in the measures, and usage define the visual pair. Considering between 1880 and 1930 there were many observations that stated they could not confirm the star was real. Having 4 sources saying Rigel BC and 21 measures using BU 555BC (There are 25 observations up to 2005.) can hardly makes this common usage. The table of measures in the WDS only uses BU 555BC.

Still, pretty good work to find these in those sources! (I've fixed your reference above for clarity.) Arianewiki1 (talk) 03:57, 12 April 2019 (UTC)

Umm ... you might be over-interpreting things. I was providing information for the discussion on what to call these stars. I don't have a strong opinion on the subject. Attic Salt (talk) 12:55, 12 April 2019 (UTC)

Hey @Lithopsian: what you reckon about buffing this one to GA-hood, which will act in sorts like a Stable Version? I was abit baffled by these results, which make it considerably less luminous than some others. Would be good to put all results and how they were derived. I do like it when we embrace uncertainty but showing how different results are derived and the certainty of 'knowing' them. Cas Liber (talk · contribs) 19:36, 24 January 2019 (UTC)

PS: There were a few new papers in 2017-18 that looked like they study some interesting stuff like mass loss and membership of larger group. Cas Liber (talk · contribs) 19:37, 24 January 2019 (UTC)

I'll certainly try to improve things. I started off seeing the new papers, but then found a lot of what was there already needed tidying up. The low luminosity is a surprise: it comes mainly from a lower temperature, the radius is very much in line with previous results. It is hard to criticise the temperature, it is newly derived using model atmospheres and SED fitting. This is way out of line with more previous results, but also a different method to the previous results which tend to use spectra rather than SED fitting. A trivial calculation from brightness and distance (260±20 pc from Hipparcos), even assuming no extinction which is thought to be the case for Rigel anyway, and taking any remotely sensible bolometric correction for a B class supergiant, gives a luminosity a little over 100,000 L_☉. It isn't a coincidence that this is the number derived by earlier studies, but assuming the distance is correct it sets an absolute lower bound for the luminosity, suggesting that the new result is flawed. Roll on Gaia. I'm thinking to discuss the new results in the text but not put them in the starbox, much as I hate to "ignore the data". Lithopsian (talk) 20:30, 24 January 2019 (UTC)

Yes - I think it is important to include it and hopefully there is a subsequent paper that clarifies why it is wrong. Luckily kisa are only preoccupied with superlative or exaggerated results...Cas Liber (talk · contribs) 19:40, 25 January 2019 (UTC)

" Roll on Gaia." Eh? Gaia accuracy for stars above 4th magnitude cannot be measured. Rigel has no Gaia data. Just saying. Arianewiki1 (talk) 01:45, 30 January 2019 (UTC)

"The 230 brightest stars in the sky (G < 3 mag, loosely referred to as very bright stars) receive a special treatment to ensure complete sky coverage at the bright end" and "it is expected that a single-measurement precision of 100 μas will ultimately be achievable, which corresponds to end-of-life astrometry with standard errors of a few dozen μas".^[1] So Rigel isn't in DR2, but will be in the final catalogue, with a precision that should comfortably exceed Hipparcos and at the very least confirm or contradict previous parallaxes. Lithopsian (talk) 17:33, 30 January 2019 (UTC)

Wow, can hardly wait....Cas Liber (talk · contribs) 03:34, 31 January 2019 (UTC)

Again. Clutching straws here, eh? Distance requires a parallax. DR3 will still have nothing but an estimate of Rigel's position. That's the whole point. Arianewiki1 (talk) 04:34, 31 January 2019 (UTC)

How do you figure that? Cas Liber (talk · contribs) 07:51, 31 January 2019 (UTC)

Clearly. "So Rigel isn't in DR2, but will be in the final catalogue, with a precision that should comfortably exceed Hipparcos and at the very least confirm or contradict previous parallaxes" is another false statement. The brightness of the star (and those above 3rd magnitude) greatly exceeds the threshold of the detector. Arianewiki1 (talk) 02:23, 2 February 2019 (UTC)

Suit yourself if you aren't going to listen or learn, but for the information of others here's an update paper on Gaia and very bright stars^[2] and a presentation with nice pictures. 151.230.113.97 (talk) 16:56, 2 February 2019 (UTC)

Clearly facts trumps speculations. Sadly the inherent errors by Gaia become larger for bright stars, becoming likely on par with HIP. I.e. 1 mas. Your linked reference clearly concludes: "Virtual object synchronisation may mitigate some of those problems for the 50 stars brighter than G=1.75. " The problems in reduction and calibration of GAIA data in the case of bright stars (above 3rd magnitude) are not simple, and these given references point this out. If you read pg.9-10, Gaia could not detect the star's core to get any astrometry, and this was for stars with G magnitudes between 1.1-5.0. Rigel is bright than 1.1G magnitude (they define it as an ultra-bright stars BTW. ). They even summise "The final astrometric error of these observations will be the sum of the formal precision and the residual calibration error, which will therefore be larger than the numbers derived as the ultimate limit from the Cramer Rao lower bound. Here, we do not quantify how well these data can be calibrated." (My bold.) If you read the conclusion (pg.11), they say: "We presented a technical solution that would allow the collection of Gaia astrometric and spectrophotometric data for extremely bright stars (G < 2).'" this does not include Rigel. Worst it is unclear with their method will be adopted with GAIA mission. e.g. "It is however not yet clear whether this mode will be adopted for the remainder of the Gaia mission." (pg.11).

Your claims of me not understanding the sources are unjustified. Simply, the misleading statements criticised by me are quite justified.

Another gross error is your edit saying "Remove Simbad-specific codename." Actually it is the name of the variable in GVSC, and was added to counter this incorrect statement that Rigel has no variable star designation. It does. (I have now restored this.)

NOTE: Good to see another anon IP present an argument and attempt to deride an argument based solely a series of edits on Rigel alone. Suspicion infers this is likely socking to avoid legitimate scrutiny, made worse by the evidentiary discussion and criticism here. Are you a sock of Lithopsian? Arianewiki1 (talk) 00:54, 3 February 2019 (UTC)

Maybe we can get back on track for making this a good article? Attic Salt (talk) 19:04, 9 April 2019 (UTC)

Still some stuff to sort out....Cas Liber (talk · contribs) 13:33, 10 April 2019 (UTC)

I tried to copyedit through the changes of the last couple of days, but ended up reverting some of it completely, so that might need going through again. It doesn't feel like we're getting any closer, just seems like the same problems going round day after day. Lithopsian (talk) 15:05, 12 April 2019 (UTC)

Attic Salt has modified the 3rd paragraph here of the Introduction from:.

Rigel's brightest companion (Rigel B) is itself a likely triple star system whose centre is separated from Rigel by 9.5″. Rigel B and Rigel C components form a very close and equally bright visual pair that is only visible with moderate sized telescopes. Together they have a combined apparent magnitude of 6.7 or 400 times fainter than the supergiant primary star. Rigel B is itself a much closer spectroscopic binary composed of the components Ba and Bb, whose tight separation is less than 0.1″.

to:

Separated from Rigel by 9.5″, two companion stars, Rigel B and Rigel C, are very close to each other and approximately equal in brightness. They are a visual pair that can be resolved by a moderately sized telescope. Together they have a combined apparent magnitude of 6.7 or 400 times fainter than the supergiant primary star. Rigel B is itself a much closer spectroscopic binary, with components Ba and Bb that are separated by less than 1 mas."

They claim in their reasoning that "No, this was acceptable." Ignoring who actually says this, is is clear the context explained extensively within the Rigel talkpage that the ""Rigel's brightest companion (Rigel B) is itself a likely triple star system whose centre is separated from Rigel by 9.5″

Also in a previous edit, they had again removed "Rigel's brightest companion (Rigel B) is itself a likely triple star system whose centre is separated from Rigel by 9.5″", on the basis that "This is not a good thesis sentence for this paragraph. Technical detail doesn't belong in thesis sentence, and possibly doesn't belong in the lede. Confusing assertion that Rigel B is "likely" a triple star, when body of article only says "might". Then rest of paragraph only discusses Ba and Bb. So remove." This complaint makes little sense. Again we do not know for certain these stars are attached, so writing in absolutes terms in not possible. Science is mostly about probabilities and evidence. e.g. Rigel Ba and Bb are a binary and physically attached. Star C is uncertain. Saying "likely" or "might" is better than saying something that is false.

There is significant difficult in writing this factually and concisely, and admittedly both versions do miss essential points.

The triple star ID is mostly based on the Washington Double Star identification, stating the pair is STF 668A,BC. As Rigel B is the unresolved spectroscopic binary (Stars Ba and Bb) with Rigel C comprise the triple star system, which may or may not be physically associated. The distance of 9.5 arcsec is presented in the WDS is written as A,BC because past measures of the pair cannot be distinguished between the B or C stars. It is better to say the distance is the midpoint of the three stars (Ba, Bb, C) I'd think.

Again after reading this, I have expanded and rewritten this Introductory 3rd paragraph. The important issue is the visual pair with Rigel B, which is visible in ordinary telescopes and is of most interest to the reader, but Rigel C and the spectroscopic binary components remain essentially unresolved. Although this latest version might be further condensed, the summary explains the stars' relationship between them. Grammar corrections might be necessary, but Attic Salt shouldn't be changing the context. Arianewiki1 (talk) 03:37, 12 April 2019 (UTC)

Hello Arianewiki1, my concern with the original paragraph (you've reproduced it yourself in your commentary) concerns what it says about Rigel B. The first sentence says that it is a "likely triple star system". But the last sentence says that it is a "spectroscopic binary". You might have some interpretation as to what all this means, but most readers would find this to be contradictory. Attic Salt (talk) 13:16, 12 April 2019 (UTC)

Thanks for this response. The difficulty is that Rigel B in some sources is considered only as the visible single companion star (e,g.). (Lithopsian has stated this too.)

Meaning that :

• Rigel (or Rigel A) and Rigel B forms the visual pair (STF 668 AB) discussed in the initial statement (two lines). (9.5″ apart)
• Rigel B itself is another double star (BU 555 BC), whose primary is Rigel B with companion is Rigel C (or formally component BU 555C). (~ 0.1″ apart`)
• Primary star Rigel B is again double, but is the spectroscopic binary Rigel Ba, Bb, where Ba is the primary and Bb is the companion. (0.001″ apart.)
• Rigel C, Rigel Ba & Rigel Bb form a triple star, that together are the single unresolved Rigel B
• Rigel A (primary) & Rigel B (secondary) equals Rigel A (primary) & collectively Rigel Ba, Bb, C (a triple.)

Each star is shown in the Starbox and in the relationship figure of the arrangement in the Hierarchical scheme.

Re-reading the new text and have added further clarification

Rigel appears as a visual pair that can be resolved by small to moderate sized telescopes. The much fainter 6.7 magnitude companion, known as Rigel B, is separated from Rigel by 9.5″, but is often difficult to view as it is 400 times fainter than the primary star. Rigel B forms another very close double star (~0.2″) with Rigel C, whose two components are approximately equal in brightness. Star Rigel B is again a much closer unresolved spectroscopic binary (Rigel Ba and Rigel Bb) that are separated by less than 1 mas. These three stars together may form a physical triple star whose centre of mass is orbiting its bright supergiant primary."

Before again changing this paragraph in the article, how can the context be further improved?

NOTE: Writing this paragraph, the assumed compromised constraint using the component nomenclature: Rigel (meaning primary Rigel A), Rigel B, Rigel Ba, Rigel Bb & Rigel C. Arianewiki1 (talk) 02:34, 13 April 2019 (UTC)

As a lede paragraph, it needs to be consistent with the content of the body of the article. When I modified the paragraph, I was using the figure in the section "Stellar system" as a guide. One difficulty I find with your writing is the use of the word "form", which (to me) introduces ambiguity. So, for example, here: you refer to "These stars" (meaning Rigel Ba and Bb) "forming" a physical triple star orbiting its bright supergiant primary. Very confusing, as it sounds like you are saying that two stars (Ba and Bb) are a triple. I believe that the average Wikireader would be confused by such a description. Please consider proofreading what you write and try to write more clearly. And you can stop trying to discourage me from editing ("Before again changing" and abundant examples on my talk page written by you). Attic Salt (talk) 13:58, 13 April 2019 (UTC)

Your behaviour shown here is simply appalling, especially towards trying to deescalating the dispute. That you even consider that the disputed text reflects the section 'Stellar system' shows you've misunderstood it and the context. The paragraph your pushing is factually wrong. Two main points then:

1. "Separated from Rigel by 9.5″, two companion stars, Rigel B and Rigel C, are very close to each other and approximately equal in brightness." Here 'Rigel B' is the visual component to the bright star (Rigel A), which is: "They are a visual pair that can be resolved by a moderately sized telescope NOT the stars Rigel B and C stars. The Rigel B and C stars are mostly not seen any telescopes because they are too close together to resolve. The statement is factually wrong.
2. "Together they have a combined apparent magnitude of 6.7 or 400 times fainter than the supergiant primary star." The stars Ba, Bb and C have a combined magnitude of 6.7 NOT just Rigel B and C. The statement is factually wrong.

My text: "Rigel appears as a visual pair that can be resolved by small to moderate sized telescopes. The much fainter 6.7 magnitude companion, known as Rigel B, is separated from Rigel by 9.5″, but is often difficult to view as it is 400 times fainter than the primary star." This is 100% correct because this is how it appears in the telescope. I've seen it myself.

The clear proof that Attic Salt is misunderstanding the text is saying that: "These stars" (meaning Rigel Ba and Bb) "forming" a physical triple star orbiting its bright supergiant primary."

No. It means Rigel Ba, Bb AND Rigel C are make the triple star. (Sure the word 'forming' might be changed to something else. e,g. creating, making, constituting, etc., but it is hardy ambiguous.) Also a 'physical triple star' is also different from a 'triple star', as one is known to be These stars together may form a physical triple star orbiting its bright supergiant primary. attached the other meaning three star close together in the sky.) Disagreement between the words 'likely' and

But if you did think "These stars together may form a physical triple star orbiting its bright supergiant primary.", then instead of just reverting everything, it would be better to change the text to : "These stars (Rigel Ba, Bb and C) together may form a physical triple star orbiting its bright supergiant primary." Alternatively, tag the questioned part of the text or seek clarification on the talkpage as being discussed here.

Again. Do you even realise Rigel B divides as two stars, being Rigel Ba and Rigel Bb (spectroscopic binary star) OR Rigel B can be described Rigel B and Rigel C (a double star) OR Rigel B can be described as Rigel Ba, Rigel Bb and Rigel C (triple star) BUT ALSO through most telescopes Rigel B only appears as a single star?

This is what needs to be conveyed. (I've openly said this is hard to convey in a paragraph.)

Yet you've now come back now claiming "And you can stop trying to discourage me from editing ("Before again changing" and abundant examples on my talk page written by you.)"

The opposite is actually true. If you can improve of my latest version, go for it. I've openly requested "Before again changing this paragraph in the article, how can the context be further improved?" and "Grammar corrections might be necessary, but Attic Salt shouldn't be changing the context."

So instead of working together to improve the context (or readability) and get some consensus, you've again revert the text back to a version that is not factually and proven as wrong. I thought is better to write out the context in full then work through the problems, but as usual, you create some pretext of 'ambiguity' or that '... the average Wikireader would be confused by such a description". That is just an opinion, which seemingly already based on wrong preconceptions and assumptions Attic salt has made. The utter audacity to say: "As a lede paragraph, it needs to be consistent with the content of the body of the article." when I was the editor who updated most of the section and have declared expertise and am a published author on the subject. If I don't understand the content and context, then who does?

Note: I have removed the disputed paragraph as there is no consensus of the facts, and I guide Attic Salt towards policy of onus, burden and undue weight. This edit shows this applies to Attic Salt , especially as you have not proven that "Confusing assertion that Rigel B is "likely" a triple star, when body of article only says "might". Then rest of paragraph only discusses Ba and Bb. So remove." (While writing this response, Attic Salt has again reverted this edit under the excuse "Restore material deleted without explanation." The above is the explanation. Instead of falling in edit warring, I will just tag the section as verification needed . Arianewiki1 (talk) 02:08, 14 April 2019 (UTC)

@Lithopsian: I have restored most of this edit Saying as an reason that; "too much of a mess of contradictions and flow problems, give up and start again from the previous version" is quite unjustified. Again, it looks like deliberate provocation in which I've pointed out before., as have reasonably attempt to improve the text. Perhaps you missed this talkpage section and the need to fix this paragraph. Frankly. If you think it has 'contradictions or flow problems', then prove it. If it is wrong, then prove it. I do agree the text might need some tweaking or improvements or simplified, but this should at least done by consensus using PARTR. (This is made more difficult by you selectively refusing to interact with other editors, making BRD impossible.) Arianewiki1 (talk) 01:09, 13 April 2019 (UTC)

There is a significant contradiction in the text within the 'Physical characteristics' section.

"Rigel is a blue supergiant that has exhausted the hydrogen fuel in its core, evolved away from the main sequence, and expanded and cooled as it has progressed across the Hertzsprung–Russell diagram. (ref seeds) Stellar evolution theory finds that massive stars can make several reversals in direction Its pulsation properties suggest it may have already passed through the red supergiant phase, although the surface abundances are only compatible with this if certain assumptions are made about internal convection. (ref saio)"

Each sentence says/implies the exact opposite, e.g. The Seeds cite says this, but the next sentence by Sato contradicts this. If it had passed through the red giant phase and the star is now a blue star, the star logically must be getting hotter. Discussion of this has already appeareds on the talkpage section 'Exhausted H in core vs Almost exhausted H in core' (with the Claudio Ritossa cite.) Factually, it maybe going either direction. Hence, "cooled" removal takes away this obvious contradiction, and even "expanded" is not necessarily true?

Since it has been reverted twice now, the article tags should remain until consensus is reached. Arianewiki1 (talk) 03:54, 14 April 2019 (UTC)

Comment. I did replace "and cooled" with "and brightened", which when looking at the H-R Diagram in Seeds reference, but even this increase in luminosity has the same problem with contradictions. Arianewiki1 (talk) 04:08, 14 April 2019 (UTC)

Thank you for explaining this. Attic Salt (talk) 12:47, 14 April 2019 (UTC)

What part is the problem? Fact 1 - it has left the main sequence - ergo it has cooled and brightened. The issue is whether it has already been a red supergiant (hence has cooled and it getting hotter), or is still cooling. So you arguing about Fact 1 is plainly wrong. I find it hard to assume good faith with this. Hence this is what we write. Cas Liber (talk · contribs) 13:49, 16 April 2019 (UTC)

In fact, Arianewiki1 rather than dumping crap on everything (again) with tags, why don't you write in plain, succinct and grammatical English what you think it should say? Cas Liber (talk · contribs) 13:55, 16 April 2019 (UTC)

So, are we saying that as stars move off the main sequence into giant phase, have they exhausted their core hydrogen or almost exhausted their core hydrogen....? Cas Liber (talk · contribs) 07:19, 22 March 2019 (UTC)

With this edit: it is now said, in the lede, that Rigel has "started to exhaust" its hydrogen, but in the section on Physical Characteristics, it is said that the hydrogen is "almost exhausted". This will sound inconsistent to some readers, and it needs to be fixed. Attic Salt (talk) 11:34, 22 March 2019 (UTC)

changed to "depleted" and "largely exhausted" so they don't contradict each other. Cas Liber (talk · contribs) 14:38, 22 March 2019 (UTC)

The hydrogen fraction in the core is effectively zero by the end of the main sequence. Rigel is well past the main sequence. There is no "started to exhaust" or "almost exhausted", the hydrogen is gone from the core. The word exhausted is usually used, perhaps because it allows for the odd hydrogen nucleus still floating about in there unable to find a partner. Rigel is currently fusing hydrogen in a shell, possibly with some helium burning in the core, references available if we want to get specific. We probably don't because the models are uncertain and contradictory except for the basics. Lithopsian (talk) 16:41, 22 March 2019 (UTC)

Do folks feel happy about this now for GAN? Cas Liber (talk · contribs) 20:29, 22 March 2019 (UTC)

"Rigel is well past the main sequence." is not quite true. A main sequence star is defined as luminosity class 'V' not 'Ib' as for Rigel. It is positioned near the main sequence on the H-R Diagram, but Rigel is not a main sequence star. High mass stars evolve almost immediately from the top left towards the top right of the HR Diagram, whose direction changes several times before going supernova. If the hydrogen were fully exhausted in a star it is likely to be a red giant not a blue star. Lithopasian is right in saying it is fusing hydrogen in the core is in a shell, but the energies being produced is mostly by other nucleosynthesis processes in the core (mostly helium burning. Hydrogen, however, is still being burnt, but the shell is slowly narrowing. The source of hydrogen is available by convection from the bulk of the star. When fuels are finally exhausted, the core collapses, creating the supernova. Arianewiki1 (talk) 22:25, 22 March 2019 (UTC)

Unbelievable garbage, just plain wrong. You really need to consider your position wrt WP:CIR and stop disrupting everything that is written by almost every other editor. I have no doubt you will take that as a personal attack, but it needs to be said. Lithopsian (talk) 14:56, 25 March 2019 (UTC)

I thought you were ignoring me… However, I'll take these provocative and emotive comments with a grain of salt, because they will damage to you far more than they damage me. It is yet another example of trying to deflecting criticism just to hide one's own lack of wisdom or knowledge. Attempting 'accusing the accuser' is weak and boorish behaviour, made worst without even presenting actual evidence.

1. If you think Rigel is/was a main sequence star, then you certainly shouldn't be editing this article.
2. Plainly (from your own words) If Rigel is burning hydrogen in a shell in the core it can't also have exhausted all the hydrogen. Surely an open contradiction.
3. Direction changes across the HR Diagram (called blue loops) and recent research shows is enhanced by mass loss. (See "Physics of the blue-to-red and red-to-blue transitions in the evolution of massive stars - I. From blue to red" by Claudio Ritossa for the general concept actually works. Many other sources discuss this.
4. James Kaler also says: "Only about 10 million years old, Rigel should eventually expand to become a red supergiant very much like Betelgeuse is today, by which time it will be fusing helium into carbon and beyond in preparation for its eventual explosion as a supernova. (Given the various observational and theoretical uncertainties, it is also possible that the star has a somewhat lower mass of say 14 solar or so and that it is now fusing its helium after already having BEEN a red giant that shrank some and heated at its surface to return to blue supergianthood)"

As for this section, much of this whole section is just openly rewording James Kaler Arianewiki1 (talk) 01:47, 26 March 2019 (UTC)

Lithopsian obviously doesn't think that and I am puzzled as to how you come to that conclusion. The shell and the core are generally held to be in different parts of the star. If Kaler is summarising then obviously the overall content is going to resemble it. There is no similarity of wording however. Cas Liber (talk · contribs) 10:15, 26 March 2019 (UTC)

"The shell and the core are generally held to be in different parts of the star." Nope. Stellar core : "A stellar core is the extremely hot, dense region at the center of a star. For an ordinary main sequence star, the core region is the volume where the temperature and pressure conditions allow for energy production through thermonuclear fusion of hydrogen into helium." Stellar cores can have structure depending on the age and mass of the star. Above any stellar core is the radiative zone. Dystopian astronomy at its worse.Arianewiki1 (talk) 22:19, 26 March 2019 (UTC)

@Arianwiki1: then why do sources talk of core burning and shell burning hydrogen? It's late and I will have a read and think on this Cas Liber (talk · contribs) 14:50, 18 April 2019 (UTC)

Clarification. In deference to Lithopsian sledges, you misunderstand the early stellar evolution of supergiant stars. The problem is the main sequence stars are dwarf stars (luminosity class V) are they reside on this line for 90% of their lives. However, supergiants do not do this because of the rate they consume their fuel. They do not reside or live on the main sequence but rapidly cross it, and the very moment they meet it, the star is still shrouded in its bearing nebulosity. A helium core develops and the hydrogen is depleted but NOT ended. This is why the H-R Diagram in the very top left does not show a continuous line but a vacant gap between the luminosity classes. Looking at Ryan "Stellar Evolution and Nucleosynthesis" (now in the article) pg. 91 has a figure showing a supergiant crossing the main sequence line.

The failure is the precision of the language used and gives an ambiguous contradiction in the meaning of the main sequence itself. e.g They don't move off the main sequence nor end of the main sequence, they move straight through the main sequence. My apologies, I should have been clearer in my statements. Arianewiki1 (talk) 00:58, 18 April 2019 (UTC)

@Arianwiki1: okay I get that point. Again I will have a read of the book...but we still have articles on things like O-type main-sequence stars. I mean, yes they only spend a very short time on it...but then again their whole life is short...? Cas Liber (talk · contribs) 14:50, 18 April 2019 (UTC)

Seriously? After endless bouts of over-tagging, stealth reverts, walls of words, abuse, and threats to individuals, we finally get an explanation and it is this fantasy? Massive stars have perfectly normal, if short, main sequence lives and they are visible with class O spectra and main sequence luminosity classes. At around the mass of Rigel, they are late class O stars and the main sequence lasts 5-10 million years. See 10 Lacertae for an example. The whole of the post-main sequence life for a star such as Rigel is under a million years. See here for a fairly readable overview (many other undergraduate course notes are available to read online), or here for a more detailed explanation that should be understandable without too much prior expertise. For a reasonably recent journal paper discussing stellar evolution at solar metallicity, see here, and for one concentrating on massive stars, here. If you're still the slightest bit unsure, I suggest asking someone independent with some background in astrophysics to come and debunk this so we can finally move on with the article. Lithopsian (talk) 19:26, 18 April 2019 (UTC)

@Lithopsian: @Ritchie333: In saying: "Seriously? After endless bouts of over-tagging, stealth reverts, walls of words, abuse, and threats to individuals, we finally get an explanation and it is this fantasy?" Character assassination to get a point across is unacceptable behaviour here, and in expressing: "...abuse, and threats to individuals", are very serious accusations. Saying so with any actual proof is straying into the area of another personal attack. (Justification from my submission here being somehow "a threat" is simply implausible. e.g. Pointing out actual editing policies cannot be construed as a threat.) By using further abuse to subdue an alleged abuser is the very definition of bulling, and it leads to questions of your own motives as to why. This here is another example.What is more revealing is these recent edits here just BEFORE your response above. Is this now your pertinent example of some "stealth reverts" or perhaps someone wanting the ire of some admin to permanently end my editing here? (I've pinged an admin here just in case.) I've act in good faith, and nearly every change has corresponded to an appropriate explanation (right on wrong) on each talkpage.

Yet, I do appreciate your response and cites above, I've read them, though it doesn't change my views or knowledge. The central problem with all massive stars is they "lose very large amounts of mass, enabling some of them to evolve back to the blue part of the HR diagram" Table 2 here and is a very good illustration. The article says Rigel's mass is now about 21±3 solar masses. If so, the initial mass must have been about 35 to 40 solar masses pre-main sequence - lasting according to this Table 2 - about 3 million years. If 24±8 is true this is even shorter. For Rigel, saying "...the main sequence lasts 5-10 million years" isn't quite ringing true. Furthermore, in saying: "The whole of the post-main sequence life for a star such as Rigel is under a million years.", if it were a more massive 30-40 solar masses it would be even shorter than this. Our astrophysical understanding at this is speculative at best.

Your example of 10 Lac is an interesting case, but its theoretical 26.9 solar masses will be 8.7 solar masses at the end of the hydrogen burning. (Again using Table 2.) Right?

In the Rigel article, I added under 'Physical characteristics': "Estimation of many physical characteristics of Rigel and other blue supergiant stars are difficult due to their rarity and uncertainty about how far they are from the Sun. As such, much of our understanding about their characteristics is based on theoretical stellar evolution models." I find it perplexing that the H-R Diagram in the Rigel article implies the larger massed stars appear in the upper left of the figure, but under the Blue supergiant star, this same area finds all the luminosity classes (between absolute magnitudes −10 to −3 and between the O and B spectral classes) don't join together. Why is that? If you look at 10 Lac again, the article says the absolute magnitude is −4.4, which is where the Main Sequence line appears to end as shown in the Blue supergiant star article. Between O9V or O9I, is there a difference? So a difficult question then: When Rigel was on the main sequence, was it luminosity class I, class V or something else?

Also under 'Formation', this same article says (another slight contradiction) "O class and early B class stars with initial masses around 10-300 M☉ evolve away from the main sequence in just a few million years." & "Blue supergiants are newly evolved from the main sequence, have extremely high luminosities, high mass loss rates, and are generally unstable." (If so, what were they when they were ON the main sequence?)

If you want to debunk something make sure not to just gloss over the facts. Again. There is: "...ambiguous contradiction in the meaning of the main sequence itself." Definition says the Main Sequence is where hydrogen to helium burning ends in the core, but it is also defined as a specific type of luminosity class of star that is based where it lies on the H-R Diagram. This is the "ambiguous contradiction." Arianewiki1 (talk) 02:47, 19 April 2019 (UTC)

@Ritchie333: @Lithopsian: According to Lithopsian the made this deliberate revert reasoning "revert the whole fantasy explanation of supergiant evolution, based on a book about red giants." Ignoring the WP:PA, there is no justification to do this and no consensus. Even if there are complaints of this text and cites, the explanation and cites also appears in the article page on Blue supergiant star. It is clear this revert is probably a knee-jerk reaction to the previous recent edit above here. This behaviour is unacceptable.

Rigel is a blue supergiant that has already exhausted the hydrogen fuel in its core.[67] It has evolved away from the main sequence, expanded[68] and surface temperature cooled, and now lies in the upper part of the Hertzsprung–Russell diagram.[69][4] When the star crossed the main sequence[70], and began converting hydrogen into helium in its core, the surface temperature would have been around 30,000 K.[71] Rigel's pulsation properties as a variable star suggest it could have already passed through its red supergiant phase and then increased in temperature to become a blue supergiant for a second time.[72][73] Depending on the stellar mass mass and composition of this initial red supergiant, Rigel may execute a number of so-called blue loops, caused by variations in energy production occurring in the shells.[74] Chemical surface abundances seen in the spectrum are compatible with this only if its internal convection zones are modelled using non-homogeneous conditions known as the Ledoux Criteria.[71] Rigel is expected to eventually end its stellar life as a Type II supernova,[74][10] in the process ejecting material that could seed future generations of stars.[75] It is one of the closest known potential supernova progenitors to Earth,[14] and would be expected to have an apparent magnitude of around −11 at its peak.[4]

to

Rigel is a blue supergiant that has exhausted the hydrogen fuel in its core, expanded and cooled as it moved away from the main sequence across the upper part of the Hertzsprung–Russell diagram.[66][4] When it was on the main sequence, its temperature would have been around 30,000 K.[67] Rigel's pulsation properties suggest it may have already passed through a red supergiant phase and then increased its temperature to become a blue supergiant for a second time, something that is expected for some sufficiently massive stars. The surface abundances seen in the spectrum are compatible with this only if its internal convection zones are modelled using non-homogeneous chemical conditions known as the Ledoux Criteria.[67] Rigel is expected to eventually end its stellar life as a supernova,[10] in the process ejecting material that will serve to seed future generations of stars.[68] It is one of the closest known potential supernova progenitors to Earth,[14] and would be expected to have an apparent magnitude of around −11 at its peak.[4]

I do not know which book Lithopsian refers, nor what is the exact 'fantasy' is, but the differences are minor.

An objection might be "crossed the main sequence" versus "When it was on the main sequence", but it is mostly trivial.

If the central objection is to "Depending on the stellar mass mass and composition of this initial red supergiant, Rigel may execute a number of so-called blue loops, caused by variations in energy production occurring in the shells.[74]", well Blue supergiant star says "Depending on the exact mass and composition of a red supergiant, it can execute a number of blue loops before either exploding as a type II supernova or finally dumping enough of its outer layers to become a blue supergiant again, less luminous than the first time but more unstable.[6]" Using the same source, I added Typer II supernova to the following line.

Extraordinarily, Lithopsian cites this same text here. They are reverting material they've already endorsed.

Other than that, there is not real differences here, and there is no real reason to revert everything. As such, I have reinstated this text, and request that they engage on this talkpage.

NOTE: On the evidence the edit appears to be made in vindictive spite than on editing principles. Verification of this attitude appears in the next blanking here in saying "and the misrepresentation of WDS discoverer codes which was snuck back in again in an uncommented edit." However, this text has been extensively been discussed above, the sources verify the usage, consensus and a compromise on the article's usage. (It this IAU's 'official' usage, based on recommendation by the US Naval Observatory who maintains the WDS.) Worse, they have been told this is disruptive editing here and is explained in full by me under 'Unhelpful edits on Rigel's Nomenclature' made here. As they have not responded to this, and refuses to engage with Arianewiki1 on talkpages, they have no consensus and is ignoring BRD.

As for the claim of "in an uncommented edit." Policy is crystal clear. H:FIES makes clear, it is not a requirement to provide edit summaries. That section notes that it can increase the risk of edits being reverted if their purpose is unclear, but does not authorise this. As H:ES says "It is not one of Wikipedia's policies or guidelines, as it has not been thoroughly vetted by the community." There is no justification to revert any edit just because it does not have an edit summary. Arianewiki1 (talk) 02:02, 20 April 2019 (UTC)

This is getting tiresome. When I attempt to discuss content with you, then I get accused of violating any and every policy going, acting in bad faith, am met with walls of words that are almost impossible to follow, and you maintain your bizarre interpretation of the subject in the face of any editor who dares to disagree. When I don't engage then I'm accused of violating any and every policy going and being "vindictive". Whenever it looks like you can't batter every other editor into submission on an article, you try to pick them off with threats and warnings n personal talk pages. Hence no discussion of content is possible with you, so get used to it. But just one final time: I'm not modifying your edits because I'm being vindictive, or because I'm trying to game the system, or because you forgot to dot some imaginary i or cross some obscure policy t; it is because you write a lot of rubbish.

Lithopsian (talk) 14:56, 21 April 2019 (UTC)

Agree with Lithopsian. Attic Salt (talk) 15:00, 21 April 2019 (UTC)

Again, discussions on Lithopsian reverts in this Section are being avoided, especially the contradiction with the same cite that you yourself added on Blue supergiant star. The rest of this response is quite unacceptable, and really should be made on User talkpages but not here. Arianewiki1 (talk) 04:04, 22 April 2019 (UTC)

The following recent edits by Lithopsian on the Rigel article are very unhelpful, to the extent that it almost crosses into vandalism and deliberate provocation. We have been actively engaged on the Rigel talkpage to gain reasonable consensus, which Lithopsian has seemingly just chosen to ignore.

The important point, which seems to have misunderstood, is that a multiple star is comprised of several double stars. (The double star designations enable the defined position angle and separation between any given measures made between two components. It is not an arbitrary distinction.) It is not simply, as said as the reason for this revision "please stop confusing WDS discoverer codes with general double star designations." It isn't. Evidence for the double star designations for Rigel appears in the WDS Catalogue, and is properly cited. e.g.

05145-0812STF 668A,BC  1781 2017  122 202 204   6.5   9.4  0.3   6.8  B8Iae:
05145-0812BU 555AD    1878 2017    7   2   1  44.5  44.5  0.3  15.4  B8Iae: 
05145-0812BU 555BC    1878 2005   25  55  30   0.3   0.1  7.5   7.6  B9

1. The multiple star designation is WDS 05145-0812, and is why they all have the same value.
2. The individual double star designations are STF 668A,BC, BU 555AD, BU 555BC.
3. The individual star designations are STF 688B for Rigel B, as BU 555Ba, BU555Bb, BC 555C and BU 555D for Rigel Ba, Bb, C and D respectively.

For simplicity, the names Rigel Ba, Bb, C and D (or variants) is used throughout the main article, with the broader consensus and cites supporting statements of the double star/ multiple star designation and usage.

(Even the Introduction acknowledges that "Rigel BC, it is actually a very close visual pair". It is the double star BU 555BC. That is the double star designation, or the older β 555 BC)

The important addition of Dickel (2000) reference is that it shows (in the figure) the designations of individual stars: thus supporting the individual star designations. It is still relevant. By removing this is ignoring both the gained compromise and consensus needed to show the actual usage of component designations. Furthermore, why even add the Argyle reference "A new classification scheme for double and multiple stars", which has nothing to do nor states anything relevant to double / multiple star designations as they are used here. It is hardly 'equivalent' and 'newer' hardly means better. The WMC method already is exactly the same as used in the WDS Catalogue exampled above.

Upon the above evidence, I have therefore justifiable reverted much of this modified text. I welcome any counterarguments within my expertise in this subject matter.

Note 1: In case the reverter hasn't seen this, in the section above "What we call Rigel's companion stars -II" I've explicitly said: "I have added this recent edit to the article page which compromises between adaptation of the non-stanadard names and the popular names and includes two adequate cites for both sources. (The article now splits this into two paragraphs.) The figure within this page from "New Concepts of Binary/Multiple Star Designation" here shows the unambiguous usage of the wider used system used for multiple and double stars."

Note 2: The Burnham double star β 555 was only changed in the WDS to BU 555 to the catalogue so it could be electronically distributed. Arianewiki1 (talk) 02:43, 2 April 2019 (UTC)

Over the past day or so, we've had three versions of the first couple of sentences in the lede. Which do we like most?

1. Rigel /ˈraɪdʒəl/, also designated β Orionis (Latinized to Beta Orionis, abbreviated Beta Ori, β Ori), is a variable star. It is, on average, the seventh-brightest star in the night sky and the brightest star in the constellation of Orion.

2. Rigel /ˈraɪdʒəl/, also designated β Orionis (Latinized to Beta Orionis, abbreviated Beta Ori, β Ori), is a first-magnitude star and a known intrinsic variable star, whose changes in brightness are not readably seen by the naked-eye. It is, on average, the seventh-brightest star in the night sky and the brightest star in the constellation of Orion.

3. Rigel /ˈraɪdʒəl/, also designated β Orionis (Latinized to Beta Orionis, abbreviated Beta Ori, β Ori), is generally the seventh-brightest star in the night sky and the brightest star in the constellation of Orion. Its brightness varies slightly and it is occasionally outshone by Betelgeuse, itself a semi-regular variable star.

Option 1. This is the one that I favour. It is short (my general preference), and I think we need to state, up-front, that Rigel is a "variable star" before we start talking about its "general" brightness. Therefore, I don't favour option 3. I think that option 2 is trying to pack too much into the first sentence. Therfore, I don't favour option 2. Attic Salt (talk) 20:44, 26 April 2019 (UTC)

Good to see your continuing to revert edits and now try to push through a version (Version 1) that is based on a illogical premise. Again, while Rigel might be a variable star, it is trivial fact about Rigel. Rigel is a bright first-magnitude star in Orion. That is what it is known for. My dictionary says "the seventh brightest star in the sky, and the brightest in the constellation Orion. It is a blue supergiant nearly sixty thousand times as luminous as our sun." (Looks like plagiarism, but that is a different matter.) The statement that it a variable star is mostly irrelevant, because the variations cannot be seen to the naked eye, and it ranking changes because of the larger brightness range of Betelgeuse not Rigel. Also for self consistency, it should also reflect the article Betelgeuse, which is already rated as a good article (GA). (It doesn't mention 'variable star' straight up.)

Again. Stop changing the context of content.

• Technically, it is an intrinsic variable star, because the changes are caused by the star itself. (It is not caused, say, be an eclipsing binary.) (You removed it,)
• I added the comment to aid editors "While the star technically might be variable, it is not the principle definition of Rigel as a bright star. Oddly, the Betelgeuse feature article doesn't use the qualifier 'variable star', as used here." (You removed it.)
• You removed first-magnitude star, which has a specific meaning. (Rigel is listed in this article.)
• You removed "highly contrasts" which was linked here 1 The reason why this is notable is that one star is blue and the other is red. The contrast is enhanced, which is why it is so noted.
• You changed "semi-regular variable star" when the linked article is named "semiregular variable star."

Frankly, your edits are not a WP:NPOV, and the evidence suggest problems with understanding context.

Your Option 1 is clearly based on a wrong premise and lacks context. Option 2 shows why is is a wrong premise, while Option 3 is a fair compromise. Arianewiki1 (talk) 23:12, 26 April 2019 (UTC)

The article contains quite a lot of discussion of Rigel's variability. Thanks, Attic Salt (talk) 23:19, 26 April 2019 (UTC)

…but the definition of Rigel is more because it is a bright star not because it is a variable star, hence it is irrelevant, especially in the Introduction. I also note: There is a pushing a POV with this same wrong premise shown here with Deneb. This kind of editing is unacceptable, because it looks like creating false consensus just to make a point. e.g. WP:POINTy. Arianewiki1 (talk) 23:54, 26 April 2019 (UTC)

I'd probably go with option 3 - it is only slightly variable. I think the main thing is that it is bright foremost. Cas Liber (talk · contribs) 23:37, 26 April 2019 (UTC)

I too would agree with option 3 — the star is foremost known as one of the brighter stars of Orion, its (slight) variabilty is not so notable. AstroLynx (talk) 13:40, 27 April 2019 (UTC)

It looks like we have a general consensus for Option 3, especially if we recognise that another editor (Lithopsian) helped author Option 3. We can probably move on from this now. Attic Salt (talk) 13:49, 28 April 2019 (UTC)

I introduced the following text by me here which Attic Salt reverted 1h 21m later here. The same edit here was reverted by me roughly 36 hours later, but was again quickly reverted 23 minutes by them here by somehow now claiming "Revert ungrammatical and redundant."

• The removal of some qualifiers explaining the facts and context is problmatic. Usage of intrinsic variable star is more precise definition. If, as the edit summary says, "This is redundant with the material at the top of the section, where "pulsating variable" star links to the same place.", then the wording of the previous usage should be changed to "intrinsic pulsating variable star", which was not done. The word 'intrinsic' is technically correct, and this modification just changes the context. (This has been removed within the same article by the same editor. e.g. Added here reverted here.)

Really. Are you saying Rigel is NOT an intrinsic variable star? It is hardly 'redundant', is it?

• Changing the text "requiring photoelectric or CCD photometry to be used." to "requires photoelectric or CCD photometry to be detected." is confusing. By removing the statement "Unnoticeable to the naked eye," (tells the reader the variations are minor and small) makes the change more ambiguous. The <qualifier> for 0.1 magnitude explains why this not seen with the naked-eye to readers who might not understand the connection. (Also grammatically '0.1 magnitudes' is incorrect, as the value is the singular 'magnitude'.) The reverter now claims this is all because it is 'redundant', but this qualifying statement was removed by them in this previous edit here. The justification in the edit line was "...This info does appear in body of article." So I put this in the body of the article here, but now this is becomes 'redundant' because you reverted that compromise in the Introduction too? Like using the word 'intrinsic' mentioned above, it has became redundant because your own reverts have made them redundant!

There seems no justification for these wholesale reverts, reflecting either issues with competence or appropriate basic editing practices.

This is another example of using strawman tactics and information suppression by minimising, trivialising or ignoring other citations of uncontroversial facts that call one's opinion into question. It is editing as if one given opinion is "right" and therefore other opinions either have no substance, or nothing to defend themselves with, and using this as a reason to under-represent it.

They are openly reminded to seek consensus before making such reverts again, and discuss changes on talkpages. (Their's is not the only 'opinion', and should remember to use the guide of WP:BRD again. This seems to be further example of POINTy, Stonewalling and gaslighting behaviour, which is against policy.) Trying to avoid scrutiny via this provocative act, leaves you open to more open scrutiny like here,) Arianewiki1 (talk) 04:10, 28 April 2019 (UTC)

Furthermore, they were already previously advised here under Talk:Rigel#First couple of sentences in lede that:"Technically, it is an intrinsic variable star, because the changes are caused by the star itself. (It is not caused, say, be an eclipsing binary.) (You removed it,)" and so this validates that an issue was already known beforehand prior to this latest revert here There's no evidence or excuse that: "Revert ungrammatical and redundant." is not a valid reason to remove. This is likely evidence of WP:DE. Arianewiki1 (talk)

The "non-consensus" edit that Arianewiki1 is refering to is my changing two sentences in the "Observation" section (subsection "Variability") from this:

"Rigel is an intrinsic variable star that has been known to vary in brightness since at least 1930. Unnoticeable to the naked eye, the amplitude of Rigel's brightness changes averages around 0.1 magnitudes, requiring photoelectric or CCD photometry to be used."

to this:

"Rigel has been known to vary in brightness since at least 1930. The small amplitude of Rigel's brightness variation, around 0.1 magnitudes, requires photoelectric or CCD photometry to be detected."

As I explained in my edit summaries (see, I use edit summaries): , this issue of "intrinsic variability" has already been mentioned prior to this point in the article. It is at the top of the Section introduction on "Observation", where Rigel is described as a pulsating variable star. The Wikilink that Arianewiki1 wants to link goes to exactly the same place as pulsating variable. I took this out because it is redundant -- we don't need to say the same thing twice in the same section.

Furthermore, the phrase that Arianewiki1 wants to use: "requiring photoelectric or CCD photometry to be used" is confusing and (essentially) ungrammatical. Used for what? "Noticing"? That seems to be verb that the sentence would imply, but that is just not good English. So I fixed it.

I hope this explanation helps. Attic Salt (talk) 12:36, 28 April 2019 (UTC)

In saying "...this issue of "intrinsic variability" has already been mentioned prior to this point in the article." is false and deceptive (verifying strawman tactics), because you had removed that from the earlier version. Your reason was it didn't appear in the main body of the article, but when I placed it in there, you deleted the text in the Introduction, then removed the text in the main body of the text again saying it was redundant. This is POINTy, stonewalling and gaslighting behaviour. Sure the article now say "small intrinsic brightness variations, " but that is not the same as technical use of "intrinsic variable star". Worse the terminology was linked to the Variable star article that explains it. The edit changes the context.

Again saying "The "non-consensus" edit that Arianewiki1 is refering to…" is another strawman tactic (being editing as if one given opinion is "right" and therefore other opinions either have no substance, or nothing to defend themselves with, and using this as a reason to under-represent it.), because you try and justify your actions, but the actual fact there is no existing consensus. Your's is not the only POV.

Also complaining that the "phrase that Arianewiki1 wants to use: "requiring photoelectric or CCD photometry to be used" is confusing and (essentially) ungrammatical.", but you fail to mention that the deleted (now ignored) initial qualifiers: "Unnoticeable to the naked eye, the range of Rigel's brightness amplitudes averages around 0.1 magnitudes…" You now delete all of that then use the change to justify your revert by claiming it was "ungrammatical." Worst, is further trying to strengthen the wording here. It is again using strawman tactics.

…yet even if there were issues with the grammar, instead of reverting it all then simply modify it. e.g. "Unnoticeable to the naked eye, the range of Rigel's brightness amplitudes averages around 0.1 magnitudes, requiring the use of photoelectric or CCD photometry" (or other alternatives.) You didn't "fix it"at all (another strawman), you effectively removed it by one global revert. (Likely done to be POINTy as in the little jab "As I explained in my edit summaries (see, I use edit summaries)" (Another strawman.) (H:ES says otherwise, which has been previously been pointed out to you many times. Counter. If you do use edit summaries, be aware of WP:EDITSUMCITE., especially when to Avoid misleading summaries)

As for this invective "I hope this explanation helps" because it seems to reenforces evidence of DE by your own omissions. Arianewiki1 (talk) 00:59, 29 April 2019 (UTC)

Lithopasian has made this reasonable edit here saying in the edit summary "variable star probably isn't the most defining characteristic, though, try this - "generally" the brightest is mostly down to Betelgeuse being variable anyway (we don't really know the "average" brightness, or at least don't have a ref for it". Whilst most of this I agree with, the removal of 'average' for 'general' creates a conflict with the associated article Betelgeuse, which uses:"...is on average the ninth-brightest star in the night sky and second-brightest in the constellation of Orion…"

For self-consistency, what adoption should be made? Arianewiki1 (talk) 07:03, 28 April 2019 (UTC)

This is a good point. I am okay with "average". I've come around on this, thanks to explanation. Attic Salt (talk) 13:04, 3 May 2019 (UTC)

me too Cas Liber (talk · contribs) 13:09, 3 May 2019 (UTC)

I think its a mistake. Average often means something specific and we don't have any support for an actual arithmetic mean for any of the magnitudes or intervals involved. It is also a weak statement. Rigel is brighter than Betelgeuse almost all the time. This is a much stronger statement, and there are references we can use to support that if necessary. I appreciate that to most people average is just a sloppy term for more often than not (average defines it quite well), but that doesn't mean we should also be sloppy when we can be more precise. If Betelgeuse is sloppy then we should fix it, not be equally wishy-washy. Lithopsian (talk) 14:15, 3 May 2019 (UTC)

Lithopsian, okay, yes, good points. I had not appreciated that we don't have data for peforming an arithmetic mean. So, let's leave the sentence as is, and move on to other issues? Thanks, Attic Salt (talk) 14:19, 3 May 2019 (UTC)

I expanded the explanation in the body, and added a citation that specifically supports what we say. It does implicitly assume the variability of Rigel, before the section where that variability is explicitly discussed, c'est la vie. Lithopsian (talk) 14:35, 3 May 2019 (UTC)

Should the corresponding issue be fixed for Betelgeuse? Attic Salt (talk) 14:40, 3 May 2019 (UTC)

Possibly. Betelgeuse currently says "average" in the lead. That's true, although it is actually more like "nearly always". The full explanation paragraph makes a number of claims about stars it can be brighter or fainter than, without any citations, so that could be better. Might be hard to find anyone explicitly classifying it against all those other stars, but perhaps a single photometry source so that we aren't synthesising results from multiple sources. GCVS (plus NVS) lists all the stars mentioned, so that might be good enough. There are books that support the claim that it can be anything from the 5th to the 20th brightest star, although it is possible they're just copied from WP. Lithopsian (talk) 14:56, 3 May 2019 (UTC)

The nomenclature section starts with considerable discussion of the etymology of the name Rigel. Then the etymology section has no discussion of etymology and just describes various non-western myths associated with Rigel. Rename the sections? Move some text from one section to the other? Lithopsian (talk) 19:52, 3 May 2019 (UTC)

The first paragraph of the Nomenclature section (except for that paragraph's last sentence about IAU) could be moved down to introduce the Etymology section. Attic Salt (talk) 20:19, 3 May 2019 (UTC)

That leaves the nomenclature section with a fairly bald statement that Rigel is called Rigel, just because. I don't mind, but maybe we could throw a bone for people that want to know why. A one-liner summary of where Rigel came from, without all the history and obscure alternative names? Capella is a clean example of what we might do. Curiously, FA Sirius doesn't even have a nomenclature section, although possibly that approach isn't an improvement. Lithopsian (talk) 20:39, 3 May 2019 (UTC)

After the first paragraph (save last sentence in first paragraph), the Nomenclature section is mostly about its scientific labels, including those for the multi-star system. To me, that is very different from early variations of the name "Rigel" and the Etymological meaning of some of those variations. Attic Salt (talk) 20:50, 3 May 2019 (UTC)

I moved the IAU sentence down to the next paragraph. This is more chronological. The first paragraph of the Nomenclature section is now, essentially, a self-contained paragraph on etymology. It might be, now easily, moved down to the Etymology section if desired. Thanks, Attic Salt (talk) 12:26, 4 May 2019 (UTC)

I've moved that 1st paragraph. I think weaknesses in the Nomenclature section are now exposed. It starts by giving the Bayer designation, then immediately gets distracted with somewhat obscure speculation about alpha/beta, relative brightnesses, and variable star designations, all of which are slightly fringe aspects of the nomenclature. Then finally slips in that it is called Rigel. Lithopsian (talk) 12:49, 6 May 2019 (UTC)

We need a short opening paragraph with a first sentence that notes that Rigel traditionally refers to the naked-eye star of what is actually a multistar system. This might be followed by a sentence on IAU designating Rigel for the primary component of the multistar system (moving the last sentence of the Bayer paragraph up to this new first paragraph). I think that would help things. Attic Salt (talk) 13:17, 6 May 2019 (UTC)

I've taken a stab at this, but the paragraph needs to be worked over. Attic Salt (talk) 13:36, 6 May 2019 (UTC)

Thoroughly worked over! Probably needs fresh eyes to give it a complete read-through. I've re-ordered bits and pieces to try and improve the flow, but in doing so might have broken some of the existing flow. Lithopsian (talk) 17:09, 6 May 2019 (UTC)

Presently, the first sentence in the Variability section says:

"Rigel has been known to vary in brightness since at least 1930. The small amplitude of Rigel's brightness variation requires photoelectric or CCD photometry to be detected."

And, at one point, the article said:

"Rigel is an intrinsic variable star that has been known to vary in brightness since at least 1930. Unnoticeable to the naked eye, the amplitude of Rigel's brightness changes averages around 0.1 magnitudes, requiring photoelectric or CCD photometry to be used." as per this edit: .

My question is not so much which sentences are better, but the factual nature of them. The CCD was invented in 1969. Photoelectric detectors were (I understand) invented before that. But before 1930, as the sentences imply?

Thanks, Attic Salt (talk) 13:43, 11 May 2019 (UTC)

This article on H-alpha looks relevant: . I'm guessing that the variability reported in this article was recorded by simply photographing the spectrum of H-alpha. Attic Salt (talk) 13:49, 11 May 2019 (UTC)

Nope. Clearly you're out of your depth. "I'm guessing…" says it all.

Photometry of Rigel was first carried out by Stebbins (1930), pub. Washburn Obs, 15, part 1, 2, who suggested Rigel might be variable.

Second sentence says the amplitude of the variations are not noticeable to the naked-eye, and require using photoelectric or CCD photometry in more recent times. Variability detection is different from amplitude, requiring more accurate measurements for the latter.

As for this edit and revert here.

Guinan, E. F. et al. (1985) as only referenced is an example indirect method. Rigel's brightness makes instrumental data difficult to obtain, which is why other means are needed to estimate distance. This same Guinan article describes "Because of the extreme brightness of Rigel, a neutral density filter was employed,…" thus telling you why. Yet you have the gaul to write in an edit summary: "Confusing. First we say that it is difficult to estimate distance because of "brightness", but then we say "brightness" illuminates nebula, and from that we can estimate distance. Remove first mention of "brightness"." Yet you'll happily make a revert just because you don't comprehend why? (It was already discussed here under Talk:Rigel#Non-consensus modification :Variability section, but you say the reason to revert is "Unexplained revert of an edit by Arianewiki1. Please use edit summaries." I've explained why already. Not knowing so is just incompetence.)

Plainly the distance estimates of the nebula infer that Rigel's distance of Rigel is better than the parallax measures (or other methods like spectral type) finding distance. The brightness of Rigel itself inhibits direct measures to determine an accurate distance. Really. Wikipedia is not an educational service. If you don't know, don't edit it, and don't expect others to clean up your messes. Arianewiki1 (talk) 08:46, 12 May 2019 (UTC)

Arianewiki1, you seem to be mixing two issues. I was asking about detecting the small amplitude of Rigel's variability. You have (possibly) answered this in your reply (I will try to filter out rudeness). The matter of brightness-distance is not, as far as I can see, addressed "already" in the talk about the variability section. You don't explain your edits with summaries, such as when you revert edits. If you did, it would help. Thanks. Attic Salt (talk) 12:48, 12 May 2019 (UTC)

This original specious fallacious assertion (above) falls under the fallacy of relevance and quoting out of context, and is another straw man tactic. Worse it is looking for fault, likely targeting another's editorship than an actual problematic issue. Saying "I was asking about detecting the small amplitude of Rigel's variability." Reading your 'question' above says nothing about the amplitude at all! The statement look deliberately provocative. (I've already told you above. "Variability detection is different from amplitude")

I think these series of edits to this edit and your revert edit here again shows motive. This is all about indirectly attacking credibility of another editor, and at the same time, also looking for and enforcing / pushing a POV. You've claimed the second version which I wrote was "ungrammatical and redundant." It is frankly disgusting behaviour.

You have not disclosed anything close to this, which is against policy e.g. borderlining and retribution.

Earlier, and another very similar kind of failure, was when you said: "Confusing. First we say that it is difficult to estimate distance because of "brightness", but then we say "brightness" illuminates nebula, and from that we can estimate distance. Remove first mention of "brightness"." This shows editing problems lacking basic knowledge and made to waste the time for everyone here. (See WP:CIR and listen again.) You've done this repeatably and keep ignoring the importance of context (especially trumping grammar over context) (Remembering your previous stance on 'intrinsic variable star' or the process of 'dredging', as previous examples.) It again shows the method of oversimplifying an opponent's argument, then attacking this oversimplified version. Again. When you don't understand something, don't edit, and don't revert unless it is clearly vandalism. Bluntness seems to be only way to get this message across.

@Stop this harassment and wikihounding – Evidence here is that you reverted my edit just because it did not have an edit summary. This is against policy as told to you multiple times. (See H:FIES and ES - last time this will be expressed) Both issues here are exactly the same wrong reasoning, which are seemingly being done to be pointy and is either being deliberately disruptive or a provocation against another in the hope of tripping them into a mistake. Also. When you save a page edit, you cannot change the edit summary, so be careful with it, particularly if you are in a heated content dispute – do not write things you will regret. e.g. Repeatably / persistently writing "Unexplained revert of an edit by Arianewiki1. Please use edit summaries" or other such variants, is personal attack and against civility policy as per not in summary & ESDonts. So please keep reverting these because it builds up the case against you by HA and DE. e.g. Stop it. Arianewiki1 (talk) 04:35, 13 May 2019 (UTC)

And now a polite answer ;) Might be best to consider that Rigel was suspected to be variable as long ago as 1930. Photoelectric photometry was possible then, although it was in its infancy. Rigel was measured and possible variability was seen, although the published result was "no variation established". It is worth noting that the apparent magnitude of Rigel was accepted as +0.34 then and until relatively recently, quite different from the modern value. As mentioned in the article, Rigel was only entered into the GCVS in 1999, so until then it was strictly only a suspected variable. The Guinan paper describes the suspicion of variability found in 1930, presumably since it has now been confirmed to be real. The brightness of Rigel, and in particular the lack of nearby comparison stars of similar brightness and colour, hinders the accurate measurement of its magnitude, especially from the ground. From space, and with more modern instruments, the variability is relatively easy to detect. Difficulties getting a good enough parallax are not related to this. Lithopsian (talk) 16:21, 12 May 2019 (UTC)

Just for information, rather than a complaint for request for changes. The brightness of Rigel is involved in the difficulty with determining its distance, but only in one rather specific way. Its moderately large distance means a fairly small parallax, certainly one that has never been determined with sufficient precision to really nail down the distance. For example, the new Hipparcos reduction parallax has a 10% margin of error and even that is twice as good as the original Hipparcos parallax. Neither of these measurements are particularly affected by Rigel's brightness. Gaia might be expected to give a sufficiently precise parallax to resolve the distance issue, but it is not designed to measure the parallax of very bright stars. I'm fairly sure that's where the brightness thing came into the question, but it may be best not to mention it unless we explain it, and trust me that is going to cause World War III. Lithopsian (talk) 15:52, 12 May 2019 (UTC)

It occurs to me that it is not so much the "brightness" that makes it difficult to estimate Rigel's distance, but, rather, uncertainty in the absolute brightness of Rigel that is the issue -- this has a big range in estimates -- and so the apparent brightness relative to absolute brightness doesn't tell us the distance with much accuracy. If this is correct and had been explained, then I wouldn't have been confused. Thanks. Attic Salt (talk) 19:51, 12 May 2019 (UTC)

The absolute magnitudes of stars are generally based on a particular assumed distance, or at least an adopted distance modulus which amounts to the same thing. Ideally, extinction is also taken into account, but not always (eg. XHIP ignores extinction). It is possible to come up with a luminosity, and hence an absolute magnitude, without knowing or guessing the distance, (usually for groups of stars rather than individuals, for example main sequence fitting for clusters) and this can actually be used to calculate a distance. However, for relatively isolated high luminosity supergiants, the luminosity calibrations are too uncertain to be helpful. Suffice it to say, all the absolute magnitude and luminosity values in the article have been calculated using a distance. Not knowing the distance of Rigel reliably, certainly not reliably to the better than 10% implied by the Hipparcos parallax, is a definite issue, an issue not restricted to 1st magnitude stars. Lithopsian (talk) 20:11, 12 May 2019 (UTC)

Okay, thank you. Attic Salt (talk) 20:12, 12 May 2019 (UTC)

The section "Physical characteristics" first two paragraphs already explains this. GAIA alleged 'distance' will not improve this. DR2 or DR3 will not have any data on Rigel. (On this Lithopsian and I disagree, but it is irrelevant here.) Why? The star is far too bright, resulting in a more inaccurate trigonometric parallax. Its an instrumental problem too, as designs are mostly for faint stars. The small parallax is one issue, the error of the measurement is an equally great issue. We also cannot use models of stellar evolution because of both the variable spectral lines, fewer spectral lines than say solar-like stars, and the rarity of B-type supergiants left to examine. This latter problem limits determination of a spectroscopic parallax "Knowing the star's true luminosity (and thus absolute magnitude), and given its apparent magnitude, one can infer its distance immediately using the inverse square intensity law." or by a photometric parallax method. Most results in such circumstances often just use a statistical parallax based on a range of indirect methods. Arianewiki1 (talk) 23:42, 12 May 2019 (UTC)

Okay, so if all this is true, then do I expect you'll revert either this edit or this edit ? If not, why not? Arianewiki1 (talk) 06:22, 13 May 2019 (UTC)

Modification of Paragraph 2 & 3 has been attempted here. I've merged a older 'stable' version of the disputed text on the multiple star and added the clarifications of the most recent versions. It is a better compromise that previous versions.

The Paragraphs 2 and 3 have also been reversed, and follows the order of article section 'Stellar system' followed by 'Physical characteristics' of the main star.

Further changes or issues should continue here to get a consensus version. Arianewiki1 (talk) 00:01, 15 April 2019 (UTC)

Interesting that you say that a consensus version of the paragraph should be developed here, immediately after you made a wholesale change of the same paragraph. Attic Salt (talk) 20:28, 15 April 2019 (UTC)

Yes. Consensus appears to be whatever Arianewiki1 is his preferred version at the time. Cas Liber (talk · contribs) 20:43, 15 April 2019 (UTC)

OK. I'm dealing with ninjas. So be it. Why don't you guys understand that consensus requires a degree of compromise? Yet any thought of some compromise edit or simple mistake finds a revert of everything - regardless of the context or your understanding. Both of you should understand PARTR , and know: "Do not engage in discussions in edit summaries. Doing so is a hallmark of edit warring; instead, stop editing and use the talk page." So far, I've followed these precepts. I brought up these issues many times within the talkpage here using BRD. Bemoaning the constant changes doesn't fix the problems.

If Attic Salt's is now complaining to Arianewiki1 that "Interesting that you say that a consensus version of the paragraph should be developed here, immediately after you made a wholesale change of the same paragraph." then what is the consensus here?

Cut to the chase. Instead of dancing around the problem, answer this:

Do we have consensus that "Rigel B" constitutes a triple star system? Yes or No. Arianewiki1 (talk) 03:02, 16 April 2019 (UTC)

The problem is the text needs to be factual, and the continued revisions kept breaking the meaning or correct terminology. I have now several times created a version that is true, but each following edit again ignores the need context. A good example is the revert by Attic Salt justified by saying "These stars" (meaning Rigel Ba and Bb) "forming" a physical triple star orbiting its bright supergiant primary. Very confusing, as it sounds like you are saying that two stars (Ba and Bb) are a triple." They were repeatably that the triple is Rigel Ba, Rigel Bb & Rigel C - plainly counting three different stars. Sure, the text might be grammatically improved, but it must continue to be factual.

To get consensus, it is important we agree on the facts as presented. e.g. If, for example: "It includes a visual pair, Rigel B and C, and a spectroscopic pair Rigel Ba and Bb, although historically the whole triple system was referred to as Rigel B." Do either of you agree with that statement, then?

If we did follow Attic Salt's version there are four factual errors and the whole context is wrong.

Comparing the versions:

1. "Separated from Rigel by 9.5″, two companion stars, Rigel B and Rigel C, are very close to each other and approximately equal in brightness. They are a visual pair that can be resolved by a moderately sized telescope. Together they have a combined apparent magnitude of 6.7 or 400 times fainter than the supergiant primary star. Rigel B is itself a much closer spectroscopic binary, with components Ba and Bb that are separated by less than 1 mas."

1. "Although appearing as a single star to the naked eye, Rigel is actually part of a multiple star system containing at least four stars. Usage of the name Rigel strictly refers to only the brightest component, although it is commonly applied to the whole system. A visual 6.7 magnitude companion, Rigel B, lies 9.5″ away and is 400 times fainter than the supergiant primary. This is readily visible in a small telescope. Rigel B is itself a close triple star system that includes a spectroscopic pair (Rigel Ba and Rigel Bb) and a visual companion, Rigel C. These three components appears as a single star except in very large telescopes. Component C has a very similar brightness and is B spectral class."

1. "Although appearing as a single star to the naked eye, Rigel is actually part of a multiple star system. The name Rigel strictly refers to only the brightest component, although it is commonly applied to the whole system. The supergiant primary has a companion 9.5″ away and 400 times fainter. The companion is itself a close triple star system with a combined visual magnitude of 6.7 that appears as a single star except in very large telescopes. It includes a visual pair, Rigel B and C, and a spectroscopic pair Rigel Ba and Bb, although historically the whole triple system was referred to as Rigel B."

Which version is better then?

So what else now needs to be added or corrected to the final paragraph if adopted?

Should this paragraph be Paragraph 2 or Paragraph 3, based on the order in article or under the subject's title?

Note: We are talking about getting consensus on context and facts NOT grammatical BS. Arianewiki1 (talk) 00:25, 16 April 2019 (UTC)

I still find it interesting that you want “consensus” immediately after making wholesale changes. Attic Salt (talk) 01:11, 16 April 2019 (UTC)

Making unfounded and misleading statements is really bad form. i.e. I have not asked at all for ""consensus" immediately" nor made "wholesale changes." Saying so is an ad hominem and is a personal attack. Consensus is a process that is worked towards between editors. It takes time. If anything, refusing to refute my arguments, is avoiding consensus building. Talkpage consensus behaviour is clear. "Consensus can be assumed if no editors object to a change. Editors who ignore talk page discussions yet continue to edit in or revert disputed material, or who stonewall discussions, may be guilty of disruptive editing and incur sanctions."

As I said this above: "Cut to the chase. Instead of dancing around the problem, answer this:"

Do we have consensus that "Rigel B" constitutes a triple star system? Yes or No. Arianewiki1 (talk) 04:36, 16 April 2019 (UTC)

Sort of. It could be Rigel B or Rigel BC. More easily introduced first as Rigel B and then explained. Cas Liber (talk · contribs) 13:39, 16 April 2019 (UTC)

I came here per a RfC, posted above before seeing this, so am moving my comments here w/o reading all the above. Much of this looks like it's already be resolved, so you don't need my input. But I suspect that my last comment, about the IAU only allowing names in the English alphabet (what they ignorantly call the "Latin" alphabet) is not widely known and may prove interesting.

There's nothing wrong with "Rigel B" etc., as long as we're clear that these are officially informal names. It would probably be a good idea to link such informal names with their official designations in the lead (of the article or section), so that they're unambiguously defined, and then, if convenient, use the informal name in the rest of the text.

The 2015–2018 triennial report, in §2.2 'Multiple Stars', states, The informal names often attributed to other components in a physical multiple (e.g., 'Fomalhaut B') are treated as unofficial, and not included in the IAU Catalogue of Star Names. There is a footnote, As these useful nicknames with the form [proper name] [letter component] often appear in the literature, many appear in the SIMBAD database.

It would seem therefore that the IAU has no problem with people using e.g. "Rigel B", and indeed suggests it may be useful for them to do so, but presumably for the sake of clarity they will not do so themselves. I don't see any reason why we shouldn't use them here at WP. The decision to my mind is similar to deciding whether to use an official IAU proper name or the designation in an article, based on what's common in the lit and what reads well. A simple nickname would IMO trump the official designation if there are so many letters floating around that a reader may have difficulty keeping track of them.

The IAU speaks of "guidelines", and even if they didn't we wouldn't need to abide by their whims. We can use proper names they've not (yet) adopted, for example. We can speak of the "Rigel system". If the astro lit eventually comes to embrace the IAU (or some less clunky development of the current guidelines), then we should follow, but we don't need to lead the way just to be "official".

One of the general problems with the naming conventions, though not relevant to this article, is that when the IAU says names must be in the "Latin" alphabet, they actually mean the English alphabet (or an English-language keyboard), but are not knowledgeable or honest enough to say so. There is no j or w in the Latin alphabet, for example, but those letters are acceptable to the IAU because they're in the English alphabet. However, French ç, Spanish ñ, German ß, Danish æ and Icelandic ð -- all extensions of the Latin alphabet equivalent to English j and w (and two of them formerly found in English) -- are not acceptable because they're not (or no longer) in the English alphabet. Chinese names are supposed to be transcribed in pinyin, but none of the Chinese names so far adopted actually are in pinyin, as they're missing tone-marking (and probably wouldn't be written with ü if required. Though, to be fair, the Chinese themselves omit tone-marking in telegraphy.) We don't need to abide by this, and it may not prove to be stable for the IAU anyway. A skirmish against this bias was recently won with the TNO name Gǃkúnǁʼhòmdímà: initially the IAU naming committee balked because it wasn't in the "Latin" alphabet. Of course, it's in *a* Latin alphabet, just not in the English alphabet. They explained at the time that they wouldn't accept German names with ß either. But eventually they caved, and MPC 112429-112436 published the name with proper orthography (p.6, though with a layout fudge rather than Unicode, so it won't copy-paste faithfully). If star names require non-English letters or diacritics to read properly or be faithful to the lit, it's possible the IAU may cave here too. — kwami (talk) 00:05, 17 April 2019 (UTC)

There were already minor planet names with diacritics, though: consider 1446 Sillanpää. Double sharp (talk) 06:40, 1 September 2019 (UTC)

Rightey-ho. Maybe time to take another look. @Lithopsian, Attic Salt, and Praemonitus: can we have a look and point out anything that might need tweaking now? Cas Liber (talk · contribs) 21:02, 23 September 2019 (UTC)

• PS: Trying to look through the walls of text above to see if anything essential that needs to be revisited...though tempted to archive the lot.....Cas Liber (talk · contribs) 21:08, 23 September 2019 (UTC)

I think fresh eyes need to take a look. It doesn't read well to me, but I might just be utterly fed up with the whole article. Lithopsian (talk) 19:18, 1 October 2019 (UTC)

Okay, I think that is understandable. I'll put it up for Peer Review (see Wikipedia:Peer review/Rigel/archive1) and if one or two fresh sets of eyes have a look for readability and flow that is a start. Cas Liber (talk · contribs) 20:10, 1 October 2019 (UTC)

Well I ended up making quite a few edits, but still a peer review would be helpful to assess the overall tone. Lithopsian (talk) 14:47, 2 October 2019 (UTC)

Okay - well trying to get folks to look at this article has been like an echo chamber - no comments in a peer review or after mentioning it on discord chat. I am asking Mike Peel to take a look. After that, maybe we should just nominate at GAN as it seems to be about the only waystep we can get another set of eyes on it. Cas Liber (talk · contribs) 23:55, 24 January 2020 (UTC)

Okay @Izno: I have reorganised the lead. I agree the nomenclature section is a bit heavy so far up the page - I am musing on moving para 3 of the nomenclature section to the stellar system section as it deals with the multiple components (??) - @Lithopsian, Attic Salt, and Praemonitus: - Izno has been the only person to comment despte me asking around alot and putting it up for peer review with zero feedback. I think it is within striking distance of GA-hood so will list it there soon unless anyone objects strongly Cas Liber (talk · contribs) 03:43, 8 February 2020 (UTC)

I have no comment on this article. Praemonitus (talk) 17:28, 8 February 2020 (UTC)

The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion:

• Hertzsprung-Russel StarData.png

Participate in the deletion discussion at the nomination page. —Community Tech bot (talk) 04:58, 9 February 2020 (UTC)

This source: https://arxiv.org/abs/1405.0907 gives a radius of 115 solar radii for Rigel. Should this diameter be added or not? — Preceding unsigned comment added by Nussun05 (talk • contribs) 12:57, 26 January 2020 (UTC)

Generally, stellar sizes are described by the radius, and an entry is already present in the infobox (look for the "details" sub-box). The reference there is from 2012, so it's possible the citation you give (from 2014) is more accurate - but an assessment of both sources would have to be made before deciding one way or the other. Tarl N. (discuss) 17:26, 26 January 2020 (UTC)

This paper is used to source the speed of the stellar wind - @Lithopsian: is it worth mentiioning its calculation of radius? Cas Liber (talk · contribs) 04:14, 8 February 2020 (UTC)

Both papers derive the radius from interferometric angular diameter measurements and assumed distances. Morravejji et al. use a 2008 CHARA measurement and the Hipparcos distance to get to 78.9 R_☉. Chesneau et al. describe the CHARA measurement as the best available, then use their own less accurate data together with 360 pc (Przybilla 2006, a very old value based on the assumed membership of the τ Ori R1 complex, as discussed in the article) to get to 115 M_☉, purely as a number to use in their model. It is worth noting that they describe the actual radius of Rigel as being between 70 R_☉ and 106 R_☉. Since this paper didn't actually intend to derive an improved value of the radius and didn't actually publish it as such, I think the older value is sufficient. We could describe some or all of this in the text for completeness.

In a similar vein, Chesneau et al. also use a luminosity value of 279,000 R_☉ in their model. It is less clear exactly where this comes from, although it is similar to the value that results from the given temperature and radius of 115 R_☉. Lithopsian (talk) 15:53, 9 February 2020 (UTC)

I added a quick mention that the radii may be larger if the higher distance is used. Lithopsian (talk) 16:01, 9 February 2020 (UTC)

The lede, the info box, and a figure list the orbital period as 24,000 years, but I don't see this particular period mentioned in the body of the article, and find a citation to a source. Can someone fix this? Attic Salt (talk) 15:19, 9 February 2020 (UTC)

The reference is Tokovinin's Multiple Star Catalogue (MSC) as shown in the starbox. The latest database entry is at Rigel. There is a VizieR table for the MSC, but older. Values like this are always somewhat speculative, but maybe should be mentioned in the body anyway. Lithopsian (talk) 16:09, 9 February 2020 (UTC)

I just grabbed the 24000 from the diagram of the orbits already in the article when trying to reconstruct the lead. Yes a source would be really really good to find. Cas Liber (talk · contribs) 02:46, 10 February 2020 (UTC)

...speaking of which, does anyone remember where the 18,000 figure came from? (I replaced it as the source supporting te statement was Tokovin which says 24,000....Cas Liber (talk · contribs) 09:59, 11 February 2020 (UTC)

The original Multiple Star Catalogue (Rigel) gave a period of approximately 18,000 years. The latest online version shows 24,000. I found there is an updated VizieR table from 2018 (Rigel). Lithopsian (talk) 17:07, 11 February 2020 (UTC)

The lead looks a little intimidating to me. Not so much the overall length, but just being two fairly long paragraphs. Maybe 3-4 paragraphs would be about right? The first one can easily be broken in half, the second perhaps not. Lithopsian (talk) 17:12, 11 February 2020 (UTC)

There's guidelines at MOS:LEADLENGTH. I don't think it would hurt matters to split it into four. That'll make it easier to digest. Praemonitus (talk) 21:34, 11 February 2020 (UTC)

I tried rejigging it thus if that helps - could be rejigged further. Cas Liber (talk · contribs) 02:45, 12 February 2020 (UTC)

Looks less scary to me, and seems to read OK. Lithopsian (talk) 14:39, 12 February 2020 (UTC)

The first sentence of this section asserts that Rigel's "spectral type" is a "defining point" for stellar classification. And for full disclosure, I believe I've monkeyed with this sentence in the past. Still, I have some concerns about this sentence. To me, it is not clear. What is meant by "defining point"? Can we say that Rigel's type "defines" a classification? Also what is really doing the defining, the "spectral type" or the spectrum of Rigel itself? Attic Salt (talk) 15:29, 12 February 2020 (UTC)

MK spectral types are defined with reference to a set of (in theory) stable stars which are "defined" to have a particular spectral type. These have been referred to as anchor points in the spectral sequence. The spectral types of other stars can then be determined with reference to the spectra of the standard stars. Rigel has been listed in several spectral type lists as being defined to have spectral type B8Ia. There are also other spectral standard stars for the type B8Ia. Lithopsian (talk) 16:58, 12 February 2020 (UTC)

The section on Physical Characteristics contains a discussion of the distance of Rigel from the Sun. This is pretty much redundant with the discussion in the Distance section, some reduction is probably needed in the Charateristics section. Furthermore, the Characteristics section contains the sentence:

Using the Hipparcos distance of 860 light-years (264 parsecs), the estimated relative luminosity for Rigel is about 120,000 times that of the Sun (L☉),[16] but another recently published distance of 1,170 ± 130 light-years (360 ± 40 parsecs) suggests an even higher luminosity of 218,000 L☉.

The first estimate 264 parsecs is cited to a source, but the second one of 360 parsecs is not. It needs to be, since the sentence is drawing a contrast, and so the reader might wonder about the validity of this contrast.

Attic Salt (talk) 14:55, 12 February 2020 (UTC)

The distance isn't discussed much in the Physical Characteristics section, but it is certainly mentioned several times. The alternative would be just saying different people have published different values for the various properties without saying why. One iteration I tried grouped the section by different studies rather than by different physical properties, so each paragraph explained the basis of the study (eg. the distance is x pc) and then gave the resulting physical properties. I think this was reverted by someone who has now been banned, hence we could revisit the idea.

Meanwhile, I added a reference for that sentence and corrected the rounding on the luminosity so it is now 219,000 L_☉. Lithopsian (talk) 17:09, 12 February 2020 (UTC)

Okay, I have nominated it at GAN as GAN is pretty much replacing Peer Review for an assessment-on-the-way. It surely must be pretty comprehensive - it will most likey just be accessibility we need to address if raised. @Lithopsian: and @Attic Salt: I didn't list you as conominators yet as I figured you'd not be wamting me to make that decision for you but you both have done alot of havy lifting so deserve it more than me. anyway, let's see what happens. I just wanna get it to some stable waypoint....Cas Liber (talk · contribs) 11:03, 14 February 2020 (UTC)

There is a section Mass loss under Observation. Is this really the right place? Mass loss is no more explicitly observed than many other physical properties, and a lot less than some. Especially the sentence about age and total mass lost since ZAMS which is highly theoretical. Surely it is just another paragraph in Physical characteristics? The age and initial mass are repeated in Physical characteristics, but perhaps should be in, or repeated in, Evolution. Lithopsian (talk) 20:20, 23 April 2020 (UTC)

The age is described in the lead, and in the Mass loss section, as being around 7-9 million years. This is based on a reference which gives the age as 8±1 million years. A range is not really an accurate way to represent a statistic margin of error. A typical reader may well interpret that to mean not only that the age is overwhelmingly likely to be within the range (else why give a range) but also equally likely to be 7, 9, or anywhere in between, none of which is correct. The most likely age (according to that source) is 8 million years, 68% likely to be between 7 and 8 million years, and 32% likely to be outside that range. Assuming a normal distribution, the age is nearly twice as likely to be 8 million years as it is to be 7 million or 9 million years. Lithopsian (talk) 20:33, 23 April 2020 (UTC)

Good point - I guess the issue is whether the average reader assumes that a range of 7 to 9 is a bell curve or just a flat sort of range. I am happy for you to reword if you can come up with something that is more accurate. Cas Liber (talk · contribs) 22:44, 23 April 2020 (UTC)

@Attic Salt: On , I don't think the image is reversed, because the Arabic text reads correctly. Probably the author of the book intended it to be like that, so that the "left leg" (which is its name, according to the article) appears to the reader's left? I also found some other images (copies of the same book), which all shows Rigel to the left of the reader (see below). HaEr48 (talk) 14:57, 24 April 2020 (UTC)

Maybe I’m cross eyed this morning, but this and the other illustrations look reversed to me. Attic Salt (talk) 15:02, 24 April 2020 (UTC)

@Attic Salt: You're right, of course. I'm saying it's probably because the medieval author (Abd al-Rahman al-Sufi) intentionally reversed it for some reason. As long as the scan is authentic, it serves a value of illustrating the etymology (the section in which I added the image) HaEr48 (talk) 15:09, 24 April 2020 (UTC)

Ah, according to The Met Museum, "the constellations each appear twice in mirror image, shown as observed from the earth and from the sky." These must be the "from the sky" version. HaEr48 (talk) 15:14, 24 April 2020 (UTC)

I don't think we should include figures that, only to avoid confusing the reader, require an explanation like this. Attic Salt (talk) 15:32, 24 April 2020 (UTC)

Sorry, I just reinstated the image before seeing that there is a discussion. Medieval star charts were commonly drawn as if they were maps of a globe seen from the outside. This is a mirror-image of how they appear to use "on the inside" of the celestial sphere. Modern convention shows star charts as they appear to us. Lithopsian (talk) 19:30, 24 April 2020 (UTC)

Okay, I accept that. I actually love the illustrations introduced by HaEr48. I suppose, then, my question is whether or not the reversed nature of these illustrations, which requires explanation, is something that should be done in this article, per se. I am happy to accept what ever people want. Attic Salt (talk) 19:48, 24 April 2020 (UTC)

Yes. Reversed images have been a thing in astronomy. A footnote explanation would be helpful. Cas Liber (talk · contribs) 19:59, 24 April 2020 (UTC)

I don't generally like footnotes, but writing half an article in an image caption is worse. Lithopsian (talk) 20:03, 24 April 2020 (UTC)

Lithopsian and Casliber, Hello, I would say that terms need to be defined before they are used. So, while "Rigel" might be the same, in some sense, with "Rigel A", at least when talking about the primary, we need to let the reader know (who is not likely to be an astronomer) that "Rigel A" is the primary, at least when we start using the term "Rigel A". That "Rigel" has been previously mentioned does not help the reader when, all of sudden, we start referring to "Rigel A" without defining it. Let us please fix things in the third paragraph of the lede. Thank you. Attic Salt (talk) 13:50, 5 June 2020 (UTC)

We screwed up - the IAU defined "Rigel" as the main component/primary. The whole is just "the (Rigel) system". and "Rigel" is the name of the main component, sometimes called Rigel A in that context, though it remains to be seen what happens as the IAU's definitions of names take hold. Cas Liber (talk · contribs) 14:01, 5 June 2020 (UTC)

Well, we all do sometimes. The last paragraph of the lede, where "Rigel A" is mentioned, needs repair. I am not happy with the convoluted nature of the first sentence of this paragraph either. Attic Salt (talk) 14:06, 5 June 2020 (UTC)

I trimmed it as it is obvious what it is 1/400th times as bright as. Cas Liber (talk · contribs) 14:08, 5 June 2020 (UTC)

That remains a problematic first sentence. I can't seem to figure out how to fix it, but the reference to 1/400th as bright leaves it confusing (to the non-astronomer reader) as to what comparison is being made. 1/400th as bright as Rigel, we know that, but the sentence is not clear. Attic Salt (talk) 14:13, 5 June 2020 (UTC)

My original wording was "400 times fainter" which is more obvious but a reviewer didn't like it. I thought it was obvious that it was referring to comparison with Rigel as what else would it be? The Sun? Cas Liber (talk · contribs) 14:16, 5 June 2020 (UTC)

"A faint companion of Rigel, referred to as Rigel B or Rigel BC, is 9.5 arc seconds away. It has an apparent magnitude of 6.7, making it 400 times dimmer." Or "400 times less bright." (Legit usage, albeit older.) Is that better? Fowler&fowler«Talk» 17:39, 5 June 2020 (UTC) Updated. Fowler&fowler«Talk» 18:00, 5 June 2020 (UTC)

FYI, this wasn't a concern of mine. My concern was about use of "away from" and "bright as" where, the association, though obvious to us, wasn't being expressed clearly (the association was with Rigel primary). I restructured the first part of the paragraph to attend to my concerns. I'm okay with either "fainter" or "brighter" since we have the association clear. My horse is now dead, Attic Salt (talk) 18:37, 5 June 2020 (UTC)

Are we all good? Just to throw a cat among the pigeons, do you think we need all the detail about component designations in the lead? As we've seen, it is difficult to express it all both clearly and concisely. It occurs to me that we could describe that there is a companion, itself triple, etc., in a lot less words and it would be easier to understand. Lithopsian (talk) 20:38, 5 June 2020 (UTC)

I'm always interested in brevity. Noting that much of our concentration has been applied to the lede, if we shorten the lede text, perhaps phrases that are removed can be used to improve text in the body. Attic Salt (talk) 20:43, 5 June 2020 (UTC)

Certainly, anything that is in the lead now should be in the body in at least as much detail. After that, possibly the lead can be simplified. Lithopsian (talk) 10:38, 6 June 2020 (UTC)

I think all the designation information is explained in the body of the article already. I edited the lead and removed all the multiple star designations. That paragraph is now slightly shorter, definitely starts out simpler, but becomes a little convoluted towards the end addressing the various orbits. See if you think it is an improvement. Lithopsian (talk) 13:52, 7 June 2020 (UTC)

Rigel /ˈraɪdʒəl/, designated β Orionis ... That makes me itch. My understanding is that the IAU decision is that Rigel refers to the A component, but β Orionis refer to the whole system - am I correct? If so, perhaps Rigel /ˈraɪdʒəl/ designates the brightest and only visible component of the β Orionis system...? That way the second sentence isn't necessary? Tarl N. (discuss) 00:23, 9 June 2020 (UTC)

I'm not sure the IAU has pronounced on Bayer designations, but certainly they tend to be used to refer to all the components of close multiple stars. For example, I don't think anyone would disagree with the designation β Orionis B, likewise β Orionis A. However, plain β Orionis is frequently used for the primary component alone, including by Simbad. I think we would be creating a precedent by insisting that it applies formally or exclusively to a system of however-many stars. The fact that you need to say "β Orionis system" suggests that it is not clear that β Orionis is the whole system. Your wording has an additional problem: "only visible" to who? I've seen Rigel B. Lithopsian (talk) 15:01, 9 June 2020 (UTC)

Rigel is actually a multi star system. But the energy output of its components other than the main star are negligable. Its average apperent magnitude is m=0.13 and the distance is d=860 ly. With these figures its absolute magnitude should be M= -6.97 . But the article gives the figure as M= -7.84. Have I missed something? Nedim Ardoğa (talk) 14:42, 6 January 2021 (UTC)

Yes, you missed something. First, the references given for the apparent magnitude, the distance, and the absolute magnitude are not the same, so they are not necessarily consistent. In fact the reference for the absolute magnitude (which I just changed to the original paper that derived the value instead of one that was just quoting it) assumed a distance of 360 pc. There is also extinction, which many people forget about. In this case it isn't obvious how many magnitudes of extinction have been included in the calculation because the paper goes directly from the distance modulus and colour excess to the absolute magnitude. However, the difference between the distance modulus and the absolute magnitude makes it fairly clear that there are about 0.16 magnitudes of extinction in there. That is consistent with the E(B-V) of 0.05. Lithopsian (talk) 17:27, 6 January 2021 (UTC)

I would rhyme this with Nigel, but is that correct? Would it be a hard G? — Preceding unsigned comment added by 2A01:4C8:1428:C467:F0B7:ED5:AF2E:FE81 (talk) 07:12, 2 January 2022 (UTC)

I rhyme it with Nigel, the 'g' as in jam. Some pronunciation guides give a hard 'g', but I haven't heard this actually being used. Lithopsian (talk) 17:38, 2 January 2022 (UTC)

And that corresponds to the tri-literal root RJL of the Arabic name (ar-Rijl al-Jauza, the foot of the giant). -- Elphion (talk) 18:27, 2 January 2022 (UTC)