Talk:Betelgeuse/Archive 3

What to do with "Sunspot" relevance?
Hi. I am beginner at article editing. (This is my first time ever to make an entry on a Talk page. Woo-hoo!) And I am finding it rather hard to learn to edit in the Wikipedia context. For example: right now, in this article, I see a paragraph that appears to my untrained eye to be irrelevant to the article. Specifically, the current third/final paragraph of "Nascent Discoveries", relating to 1950s & 1960s balloon observations of phenomena on the surface of our Sun.

My problem: I see no apparent connection between the paragraph and Betelgeuse. But I'm no expert (my degree is in biology...)

So -

If I'm unsure what to do in a situation like this, should I:

A) Go ahead and delete the paragraph, and if I'm wrong, let a "real" editor revert my change? or B) Tag the paragraph, somehow, for a "real" editor to take notice of at some point? or C) Just do what I'm doing here -- write a Talk note when I see the problem?

Your guidance would be much appreciated.

(Is there a central point somewhere on Wikipedia to put general "how to" questions like this one??)

Thanks. — Preceding unsigned comment added by Sqzx (talk • contribs) 07:44, 24 June 2015 (UTC)
 * Placing a note here is a good first step as the folks who edited the page (like me) are most likely to see it here. Many articles benefit from some material that acts to give the content some background and context. Looking back at it now I am in two minds - yes it helps tell a story but is possibly a bit circumstantial, especially given how long the article is....so I suppose what I am saying is I wouldn't object too strongly if removed. The person that mainly wrote the section,, has not been active in som time. Cas Liber (talk · contribs) 09:41, 24 June 2015 (UTC)


 * Can't see anything specific to Betelgeuse, or adding to understanding of Betelgeuse. Possibly such a paragraph might go in a general article about Red supergiants, if it actually said something, but I can't see what it adds here. Taking it out in good faith (WP:BOLD) wouldn't get you in any big trouble even if you were wrong, although repeatedly making edits that need reverting will not make you any friends.  Describe what you're doing in the edit summary, add something on the talk page if debate might be needed.  Lithopsian (talk) 13:06, 24 June 2015 (UTC)

producing not only an inaccurate radius for the star but every other stellar characteristic
Perhaps "one of the best" wiki pages could do with some coherent grammar?137.205.183.109 (talk) 15:24, 4 November 2015 (UTC)

More stuff that I think should go
This article seems to have accreted a lot of cruft. I've made some changes to particular sections of interest, but I think a lot more should be simplified, rationalised, or just plain deleted. For example, the Diameter section contains all sorts of speculation that appears to go beyond anything stated in the given references, combining values from various references to reach non-published (or at least non-cited) conclusions. I also feel that the Recent studies subsections should be dropped entirely. It is hopelessly time-dependant, so already somewhat out of date. Its contents should either be described in a historical context, or as current state-of-the-art in the relevant sections. Lithopsian (talk) 22:00, 19 August 2016 (UTC)
 * The image with the plume is notable and worth keeping in. Pretty unusual to have an image like that. I was involved in its promotion originally, and hasn't been around since 2013 really. It was pretty detailed when promoted. Not sure I agree with wholesale mass loss but happy to look at it overall - am torn as I do think that showing readers how we arrive at calculations is really important but trying to walk a tightrope and avoid making it an essay is tricky. Cas Liber (talk · contribs) 22:40, 19 August 2016 (UTC)
 * I'll see where we get with incremental changes, although I am going to do a significant rewrite of the "supernova" sub-section. There might be images that can be dropped - I'm not sure which one you refer to as three images mention the "plume" - but overall there doesn't seem to be an excess of images.  I mostly have a downer on speculative artist's impressions and content-free videos :) Lithopsian (talk) 11:23, 21 August 2016 (UTC)
 * I meant the discssion about this image - File:ESO-Betelgeuse.jpg - that occurs there. i.e. a real image not some artist's impression...Cas Liber (talk · contribs) 13:14, 21 August 2016 (UTC)

Color Index B-V
The color index given by Hipparcos catalog is 1.5 whereas the source cited gives 1.85. Since the source was published prior to Hipparcos launch I think the value should be updated. Or am I missing some point ? — Preceding unsigned comment added by 83.206.4.101 (talk) 10:13, 26 October 2016 (UTC)
 * The Hipparcos B-V index is derived from multiple sources and in this case has a very large statistical margin of error. I don't know exactly why, but appears to be a common problem for very bright stars in the Hipparcos & Tycho catalogue. It isn't hard to measure B-V and error ranges are typically hundredths or thousandths of a magnitude, not half a magnitude. Multiple other sources consistently give B-V for Betelgeuse within a tenth or two of +1.85. The Nicolet source used in the article is a weighted mean of multiple sources. A formal error range is not given but the result for Betelgeuse is considered of high quality. Additionally, a consistent U-B value is given in the same catalogue. Simbad gives photometry from an even older single-source catalogue, one of the inputs for Nicolet, but it also has B-V of +1.85.  In short, the given value looks pretty reliable and the Hipparcos number is distinctly dodgy. Lithopsian (talk) 11:15, 26 October 2016 (UTC)

Spinning, swallowing
J. Craig Wheeeler has suggested that c. 100,000 years ago. Betelgeuse swallowed a Sun-sized companion accounting for its unusually high spin-rate.

The theory has only just been published in the MNRAS (see also phys.org), I don't know what the criteria are for inclusion of new theores in astro-articles, but I note that we currently have rotational velocity at 5 km/sec, whereas they say 15 km/sec ("150 times faster than any plausible single star just rotating and doing its thing", whatever that means). --Hillbillyholiday talk 08:44, 20 December 2016 (UTC)
 * The value of 5 km/s is "v sin(i)", the projected rotational velocity. The actual equatorial rotational velocity depends on the value of i, the inclination. There is an assumption that it is 20°, but that comes with a big dose of salt. Given that, there is a reasonably well-accepted discrepancy between the very slow observed rotation rates of supergiants like Betelgeuse and the relatively fast rotation rates that give the best results for evolutionary models. The models may need tweaking (*do* need tweaking for other related things, which might solve this discrepancy), the observations might be wrong, there may be factors beyond those we already know that cause evolved stars to spin down, or funky things may have happened like swallowing a planet. No harm in mentioning a published peer-reviewed article, just don't give it Undue weight (sources). Lithopsian (talk) 17:32, 20 December 2016 (UTC)
 * Thanks for explaining, Lithopsian. I don't think I should add anything – you are evidently far more qualified – I just wanted to note the new article. You say a "very slow observed rotation rate", yet the "150 times faster" quote seems to imply the opposite? I are confused. --Hillbillyholiday talk 00:26, 21 December 2016 (UTC)

Question
Betelgeuse is something like 640 light-years away. So, if a spaceship travels only at the speed of light, it will take 640 years to get there. Suppose we assume that faster-than-light travel by a spaceship is possible (even though relativity theory says that is impossible). Suppose a voyage by a spaceship from Earth to Betelgeuse takes three days. How fast would the spaceship have to travel (how many times the speed of light) to reach Betelgeuse in three days? I'm writing a fiction novel and hope to get this detail right; I've been trying to work out the math but I am not a scientist.--Tomwsulcer (talk) 13:57, 5 November 2015 (UTC)


 * speed (assume "1" is exactly light speed, ie 186,000 miles per second)
 * time (in years)
 * distance (in light years)
 * speed x time = distance
 * speed x 640 years = 640 light years
 * speed x (3 days/365 days) = 640 light years
 * speed x .0082191 years = 640 light years
 * speed = 640 light years / .0082121
 * speed = 77867 times the speed of light

Is this right?--Tomwsulcer (talk) 13:57, 5 November 2015 (UTC)


 * Yes, although I would point out that 640 LY is only an approximate distance, give or take 20%, so “about eighty thousand” is about as precise as we can make it. (Of course in your fictional future the distance could be much better determined, but you could pick any exact figure between about 60,000 and 95,000 without contradicting present knowledge.)
 * Take note, that this page is for discussing improvements to the article, not the subject in general; please ask questions of this nature at the Reference Desk instead.—Odysseus 1 4 7  9  04:44, 6 November 2015 (UTC)
 * Thanks,, will take your excellent information into account. (I think that there is tangential relevance here, since this line of information means humans will never ever get anywhere near Betelgeuse unless we can fly faster-than-light, many multiples of faster-than-light, and what the scientific community believes is that f-t-l travel is impossible. So maybe something could be added to the article that it is seriously unlikely humans will never get close to Betelgeuse or, for that matter, any distant star?) From my experience in Wikipedia (since 2009) I've come to learn that the truly sharp folks (such as yourself) follow the talk pages of these technical articles so please forgive me for seeking out your expertise in this manner. I have not had much luck with the reference desk in the past but maybe I'll try it again next time something comes up.--Tomwsulcer (talk) 11:34, 6 November 2015 (UTC)

640 years = 640 years * 365.25 days/year = 233,760 days

233,760 days*lightspeed / 3 days = 77,920*lightspeed  172.75.129.94 (talk) 14:43, 23 December 2016 (UTC)

Total lifetime
The total lifetime from the start of the red supergiant phase to core collapse varies from about 300,000 years for a rotating 20 M☉ star, 550,000 years for a rotating 20 M☉ star, up to a million years for a non-rotating 15 M☉ star. It is not clear from this abstract nor this paper, both cited for this statement, what the correct figures are. Adriaan Joubert (talk) 21:27, 4 January 2017 (UTC)
 * This paper shows the models that this is all based on. Table 1 would be a useful reference. It contains values similar to those in the article, although not apparently exactly the same. Lithopsian (talk) 22:16, 4 January 2017 (UTC)
 * Thanks for that. I have changed the sentence in the article to read The total lifetime from the start of the red supergiant phase to core collapse varies from about 300,000 years for a rotating 25 M☉ star, 550,000 years for a rotating 20 M☉ star [...] so that the statement is now consistent with the reference you provided. Adriaan Joubert (talk) 10:48, 5 January 2017 (UTC)

Gamma-ray burst etc.
Betelgeuse is not likely to produce a gamma-ray burst and is not close enough for its x-rays, ultraviolet radiation, or ejected material to cause significant effects on Earth. The citation for this statement is this paper which is proprietary; can someone with access to the paper verify this claim? Adriaan Joubert (talk) 11:13, 5 January 2017 (UTC)
 * arXiv preprint here. Lithopsian (talk) 15:18, 5 January 2017 (UTC)

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Infobox
Why don't we put the ALMA image of Betelgeuse in the infobox? We show the surface of Solar System planets and the Sun in the box, so it would seem logical here. '' S ir  C umference π  17:38, 12 July 2017 (UTC)
 * Any image can go in the starbox. Traditionally this has been a chart or other identifying picture. I think in part this is because there were relatively few eye-candy pictures of individual stars. A star is either a blob or a dot on a largely dark background, certainly nothing resembling a surface. Now there are a few images of a handful of stars that could be said to be real and showing something. The ALMA image probably isn't the best example though, it is a reconstructed false-colour image that doesn't show anything resembling a visual image of the star - it is in fact valuable for an entirely different reason, which is apparently not mentioned at all in the article. There are UV and IR images of the atmosphere, already in the article, which could be considered more "realistic". I'm not recommending that either be placed in the starbox, just offering comment. The current starbox chart is particularly unattractive though ;) Lithopsian (talk) 16:26, 13 July 2017 (UTC)

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Betel juice
Any relation between the names Betelgeuse and the English name of Betel juice or is this wholly a coincidence? Schissel | Sound the Note! 16:54, 26 November 2017 (UTC)
 * How do you mean? Strictly speaking no, but since the movie people have pronounced it more like "Beetle juice" I guess...Cas Liber (talk · contribs) 19:14, 26 November 2017 (UTC)
 * Since the name 'Betelgeuse' comes from a corrupted Arabic phrase referring to a hand the answer is clearly No. Skeptic2 (talk) 21:35, 26 November 2017 (UTC)

As the is obsolete and is also the least reliable estimate, is the  for Betelgeuse even obsolete? I think so, due to the similar number/upper estimate.   ZaperaWiki44  (✉/Contribs) 14:05, 28 November 2017 (UTC)
 * Scrap it, except as a purely historical and refuted idea. This is why pop-science websites make terrible sources.  One brief paper suggests, on the basis of somewhat inconsistent measurements, that Betelgeuse is shrinking and a hundred stories appear on the internet (or one story appears a hundred times with a couple of words changed to make it look different).  When those measurements are refuted and explained away (Ohnaka et al 2011, Montargues et al 2014 and Ohnaka 2014), nothing.  The number 1,200 didn't even appear in Townes et al 2009, it is a synthesis of angular measurements from 15 years earlier that are no longer considered reliable with a later distance measurement which is also now obsolete.  Of course the other two given radii also use 197 pc as the distance, rather than the more recent 222 pc.  Betelgeuse could be bigger than we say!  Don't go calculating it for yourself though ;)  Lithopsian (talk) 17:11, 28 November 2017 (UTC)

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Orbital companions to Betelgeuse - a question
Hi everyone, just a quick question here. Is the following strange or self-contradictory? In Observation section, the Star System subsection begins, "Various catalogues list up to nine faint visual companions to Betelgeuse." Yet further down, in the Physical Characteristics section, the Mass subsection begins, "Betelgeuse has no known orbital companions." My reading of this leave me thinking there are either zero, or up to nine, orbital companions to the star. The Interloafer (talk) 15:33, 27 January 2019 (UTC)
 * No contradiction, visual companions are not the same as orbital companions. However, referring to "visual companions" in a section called "star system" is just plain misleading.  Lithopsian (talk) 15:43, 27 January 2019 (UTC)
 * Yeah just looking at that now. I have slotted into observation as it fits better there. Cas Liber (talk · contribs) 18:10, 27 January 2019 (UTC)

Pronounciation?
Is it pronounced "beetle-juice"? If so, can we indicate that at the beginning of the article, because I think a lot of people are not quite sure how to pronounce the name. Invertzoo (talk) 13:06, 27 April 2018 (UTC)
 * That is one possible pronunciation, but there at least two or three others. Three pronunciations are given in the starbox, one not cited, and at least one common one missing.  Might have to put my editing hat on unless some IPAC-expert gets there first.  Lithopsian (talk) 20:04, 27 April 2018 (UTC)

I've always said BET-el-jweez, but that might just be me. Cynthia-Coriníon 20:08, 25 September 2019 (UTC)

Betelgeuse is well off the low-end of its standard 50 year variable luminosity
Since the beginning of December 2019, Betelgeuse decrease in brightness has been "off the historical norm" on the low side. Many astronomers have reported this, and it has engendered much discussion on the data possibly showing that Betelgeuse is perhaps later in its red giant phase (off the main sequence) than previously estimated, and thus perhaps closer to supernova than previously thought.

Here is a chart that is showing the data from a fairly large group of astronomers who observe Betelgeuse regularly. Very interesting data. 10-day average magnitude for Betelgeuse for the past 50 years N2e (talk) 12:10, 25 December 2019 (UTC)
 * Yes, would be good to add something. Question is, what is the best source to do so with. Lots of news articles at the moment, but they are short on detail....Cas Liber (talk · contribs) 12:36, 25 December 2019 (UTC)
 * That's because there is no detail. Betelgeuse is fainter than its been for a while, that's about it.  The visual magnitude was comparable in the early 1980s and the 1920s.  The 100,000 year, and even 10,000 year, supernova numbers are not new.  They are included in the WP article already, with references, from papers a number of years ago.  So far as I can tell, there is nothing new about supernovae, just a lot of internet hype.  The only recent scientific publications are from The Astronomers Telegram (eg ) showing that it is still apparently getting fainter, approaching all-time recorded lows.  Lithopsian (talk) 16:29, 27 December 2019 (UTC)

FWIW - the following edits have been added to the Betelgeuse main article - seems ok afaik - please post if otherwise - *entirely* ok with me to rv/rm/mv/ce the edits of course =>  Copied from "Revision as of 10:54, 27 December 2019" In December 2019, astronomers reported that the star has significantly "fainted" in visibility. Betelgeuse may be in the last stages of its evolution, and it may be expected to explode as a supernova within the next million years or, as end of year 2019 studies have shown, within the next 100,000 years.

In any case - Enjoy! :) Drbogdan (talk) 16:49, 27 December 2019 (UTC)
 * As mentioned, the 100,000 years is not a new number, and it is not earlier than previously thought. In fact it specifically comes from the 2017 paper already described and referenced in the article.  There is nothing new in the recent news that changes this, it is just recycling old news for a headline.  The only new news is the faint state in December 2019.  I'm not sure this currently rates as anything other than a one-day (or one month) wonder, I suppose we'll know in a while if it amounts to more than the normal erratic variation.  Lithopsian (talk) 20:41, 27 December 2019 (UTC)

I've made some edits in this area before I looked at the talk page, then addressed the duplicate refs. I've noted the mixture of media coverage, from interesting to there is supernova speculation to implying a supernova is likely, and the Phil Plait piece on the recent discussions. EdChem (talk) 07:46, 28 December 2019 (UTC)

Need a new section?
I notice that more and more factoids and hype are getting stuffed into the lead, basically about short-term news that may or may not prove to be of longterm scientific significance. Much of it should be in the body, with a summary in the lead. In fact, much of it is already in the body and should be deleted from the lead. However, it might make sense for the content in the body to be easier to find, possibly in its own section for now at least. Either way, I'm likely to delete three quarters of the "fainting" discussion from the lead, and all of the refs, not least because the refs are mostly duplicates and fainting is not the encylopaedically-appropriate word for this behaviour.

Although there are no new sources that I can see from the last week or so, I can report that Betelgeuse is still fading quite quickly and is now hitting all-time documented lows. The light curve over the last few months is quite striking, fairly stable at mid-range then dropping nearly a magnitude in two months. However, remember WP:NOTNEWS. I will update the light curve image in the article at some point. Lithopsian (talk) 15:18, 3 January 2020 (UTC)
 * thanks for this helpful info and update. --Sm8900 (talk) 15:37, 3 January 2020 (UTC)


 * The dimming should not occupy more then one sentence in the lead, possibily after discussing the star's variability. And we should drop ALL popular news references, they all tend to overhype the situation. We should just leave actual astronomy sources, like the Telegram, variable star observation organizations, and future journal papers. Any supernova discussion should only be included if specifically mentioned by these sources. Jolielegal (talk) 23:38, 3 January 2020 (UTC)
 * I've chopped the excessive paragraph in the lead to a couple of sentences. That can be adjusted over time as the current news is shown to be either a damp squib or the beginning of the astronomical event of our lifetimes.  I merged some of the lead material into the body and put it in a separate section for visibility while this is a news event (redirect to an anchor, anyone?).  Again it can be expanded or reduced when there is more clarity.  Some copyedit might be useful, might have muddled up the flow a bit.  Lithopsian (talk) 20:16, 4 January 2020 (UTC)


 * I made a scad of changes in wording, largely under a rubric you might call PoV, were we not (no matter however appropriately:) so focused on WP:NPOV. I mean a hardly related sense of POV: I sensed what I’ll risk calling a star-gazing orientation, the risk lying in the danger of seeming to disparage that pursuit, tho I sympathize, commend, and value what observational astronomy provides and encourages for practitioners and the advance of science. My concern is for broadening the treatment, primarily by including more of the scientific fruit and/or analytical points of view, Astronomy requires some optical hardware and at least mathematical discipline, and perhaps the real core of my ed-session was to offer more of a sense that the more awareness of why the.foundational sciences can more richly facilitate awareness of scientific findings rather than just collection of quantified observations, and many insights depend on patterns, perhaps hidden, rather than plain data collection. —JerzyA (talk) 09:26, 12 January 2020 (UTC)

Pre-fading magnitude
The lede describes Betelgeuse as (usually) the 11th brightest star, but the section on recent fading describes it as having been the ninth brightest star (before recent months). The Washington Post and National Geographic sources cited in the fading section (not all accessible to me) might be the source of this inconsistency. Attic Salt (talk) 15:13, 21 January 2020 (UTC)
 * It's variable, irregularly, so there isn't really an average. The press reports generally talk of "in the top 10" quoting more or less directly from The Astronomer's Telegram.  I have adjusted that section to match and given the reference directly.  List of brightest stars gives Betelgeuse as 11th brightest at its "average" level, with the Sun at #1.  Given that five of those top 10 (other than the Sun) are variable, there is lots of scope for picking a number.  The Astronomer's Telegram is again much clearer than the Chinese Whispers, stating that at its average maximum it is within the top ten.  Lithopsian (talk) 15:45, 21 January 2020 (UTC)

Axis of rotation
This star is in the news, which should be welcome to astronomers — funding! — but the ignorant tabloid stuff might be less welcome. I’ve come from The Economist, and neither that nor Wikipedia mention anything about the axis of rotation.

I.e., is it pointing at us?

A rotation speed is listed, so something might be known about its direction. And if nothing is known, please could at least that be said? JDAWiseman (talk) 19:22, 1 February 2020 (UTC)


 * The axis of rotation is thought to lie about 20° away from us. Lithopsian (talk) 21:25, 2 February 2020 (UTC)

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"Distance measurements" subsection needs cleanup
Several of the reported measurements are garbled so that they are unreadable. Ishboyfay (talk) —Preceding undated comment added 17:57, 15 February 2020 (UTC)


 * There's a problem with the nested $\pi$ = $5 mas$ template. I've removed the "pi =" as it renders unreadable. Someone with more experience with nested templates should take a look at a permanent fix. --mikeu talk 16:16, 17 February 2020 (UTC)
 * My fault. Probably better without the πs anyway.  Lithopsian (talk) 17:54, 17 February 2020 (UTC)

For an amateur such as myself, an explanation of why it's especially difficult to measure the parallax of Betelgeuse would be a helpful addition to the article. I have in mind this sentence from an EarthSky article: "Measuring the distance to Betelgeuse has been particularly difficult because it is a variable star." As an amateur, I don't feel confident enough to explain further. Ishboyfay (talk) 18:25, 15 February 2020 (UTC)
 * Lots of reasons, but simply having a diameter ten times bigger than its parallax makes things tricky. Add in pulsations, starspots, and having an irregular silhouette.  Well, you get the idea.  Specific to Gaia, Betelgeuse is brighter than its sensors can handle so it isn't possible for the normal scan sweeps to identify the position of the star.  Special observing runs and analysis techniques have been developed which may allow Gaia to provide a parallax 1-2 orders of magnitude better than anything before, perhaps to better than a parsec.  Lithopsian (talk) 18:09, 17 February 2020 (UTC)
 * This is a great answer. If it's possible to include some of it in the article, I recommend doing so. Ishboyfay (talk) 22:18, 17 February 2020 (UTC)
 * Needs reliable sources. I'm sure they're out there somewhere.  Lithopsian (talk) 17:54, 20 February 2020 (UTC)

Marcel?
I followed the Wikisky coordinate link which for me shows up in the top-right of the article… Some joker has fiddled Wikisky so that this star seems to be named "Marcel". Searching for "marcel" on Wikisky nets me three results, including α Ori. Am I missing some astronomical in-joke or should someone be told about this? TIA HAND —Phil | Talk 11:22, 6 March 2020 (UTC)


 * That looks like vandalism to me. I'm not a WikiSky editor myself, so wouldn't know how to fix it without learning how. It needs to be changed. Well done for spotting that and alerting others. TowardsTheLight (talk) 11:59, 6 March 2020 (UTC)

Too soon?
How long before the recent dimming can be consigned to a short paragraph in the body and no more than a sentence in the lead? The news hype is over and the brightness is clearly recovering. Nothing went bang. Might be nice to have a slightly longer light curve for that section showing the whole dip and rise in context now that the brightening is so clear. 176.251.70.30 (talk) 15:05, 14 March 2020 (UTC)

New (Oct. 2020) Info
Joyce, et. al. published new estimates of several physical parameters. I am not clear on whether their paper has actually been published or is still in peer review, but based on claims of the university's PR department, it has been published. Standing on the shoulders of giants: New mass and distance estimates for Betelgeuse through combined evolutionary, asteroseismic, and hydrodynamical simulations with MESA by Meridith Joyce, Shing-Chi Leung, László Molnár, Michael J. Ireland, Chiaki Kobayashi, Ken'ichi Nomoto v5: published in the Astrophysical Journal:The Astrophysical Journal, Volume 902, Number 1, 2020. I only read the abstract. R is revised to 764(-62/+116)Solar radii, M to 16.5-19.0 Solar M, and distance to 168 (-15/+27)pc [equivalent to about 550 (-50/+90)ly. I assume this also changes its estimated absolute magnitude. Oh, I should also mention that the two recent dimming episodes are attributed to 1. a cloud passing between it and us and 2. Pulses (hydrodynamic?) of its surface, respectively.98.17.180.195 (talk) 09:38, 16 October 2020 (UTC)
 * Joyce et al (2020. Now published with some revisions.  The citation might be tricky because it doesn't look like it has been given a new bibcode yet.  I reverted your edit because it was uncited and because it contradicted the value in the starbox.  Some edits were made in August 25th, which I reverted then because the article hadn't been published at that time.  That set of edits could probably be reinstanted, with care to make sure that intervening changes don't get trampled.  Lithopsian (talk) 13:39, 16 October 2020 (UTC)
 * , I think it is time to reinstate the edits, making sure that they are consistent with the revised values on the publication. These are fairly substantial changes. S Philbrick  (Talk)  00:14, 18 October 2020 (UTC)
 * Indeed. I just haven't had time to do it myself.  Weekend, life, laziness, you know how it goes.  Lithopsian (talk) 13:16, 18 October 2020 (UTC)
 * See what you think. There probably needs to be some more edits in the body to reflect the updates.  Lithopsian (talk) 19:36, 20 October 2020 (UTC)

Nomenclature
The mentioned Arabic origin إبط الجوزاء is translated by Google Translator as "armpit of Gemini" instead of "armpit of Orion". Maybe translator problem?94.226.131.101 (talk) 15:36, 20 December 2020 (UTC)

Mass/Distance incorrect
The mass and distance to Betelgeuse has recently been discovered to be just 8.5M for Mass and a few dozen light years closer to the Sun than the estimates shown in this article. This was confirmed by two teams of astronomers already, one of which was done on Discovery Channel a couple years ago, and another was on Phys.org article just a few months ago. And this contradicts the post above me, but it is what it is.

I don't have the links to this information, but a Google search can probably find these articles and papers again in short order.

One of the studies, the one on Discovery channel, they did a survey of Betelgeuse for months on end using hundreds and hundreds of photos from the Atacama desert, and the "Lucky images" were used to determine the emission spectra and mass of Betelgeuse, and they found it was only 8.5M and was closer to the Earth than any previous estimate. — Preceding unsigned comment added by Craftmatic3 (talk • contribs) 14:12, 20 December 2020 (UTC)


 * Without any references to actual reliable sources, not just things you dreamed about while dozing in front of the Discovery channel, this is just so much hot air (pun intended). Here is the paper I believe you have mis-remembered.  It is fully incorporated into the article, but feel free to point out any areas that you feel have not been described fully or correctly.  Lithopsian (talk) 15:52, 20 December 2020 (UTC)

Anyway, 8.5M is still big enough to produce a SuperNova, as new data shows 8M to 11M stars can produce Supernovas.

Betelgeuse is currently burning the Triple Alpha Process and Carbon-Carbon burning, which produces Neon and more Helium (1/6th as much as you started with). A rare Carbon reaction produces isotopes of Nitrogen. When Betelgeuse gets dense enough to start Nitrogen-Nitrogen-H (three atoms) fusion ,it will explode in a Supernova, leaving behind a Neon core which will appear as a Neon rich core of about 5M. However, this collapses into a Neutron Star, which will produce another Supernova about 13 years later. All of this will happen in about 10 million years.

the Crab Nebula start exploded from Iron-Iron-Hydrogen fusion (three atoms) and annihilated a third of its initial mass in an anti-matter explosion. this explains the "missing mass" of the Crab Nubula more completely than "Electron Capture". The Crab Nebula Progenitor Star was too massive to undergo a Nitrogen-Nitrogen-Hydrogen explosion. Betelgeuse is too light to fuse Iron with Hydrogen, so it will explode in the Nitrogen Series.

— Preceding unsigned comment added by Craftmatic3 (talk • contribs) 13:36, 20 December 2020 (UTC)

Gail, Hans-Peter; et al. (November 2020)
This new study references an effective temperature of 3,800 K and a luminosity of, from Levesque, Emily M.; et al. (August 2005). Should this be considered at all, or the fact this study quotes old data means it shouldn't? Faren29 (talk) 20:03, 30 December 2020 (UTC)
 * Well my expectation was that having a consistent set of data from the same source was valuable for this study, so Levesque got picked. However ... Betelgeuse doesn't have a luminosity determined in Levesque et al. (2005), because it doesn't have a reliable distance, and the adopted temperature there is $3,650 K$ not $3,800 K$.  So clearly the data came from somewhere else.  For that alone, I think it should be ignored.  Further, Levesque & Massey (2020) quote a temperature of $3,600 K$ so I don't think there is much reason to change this in the article.  Similarly, the distance of $130 pc$ is pretty obsolete, not even the new Hipparcos reduction, but the original one.  I didn't look into the underlying reference to see why.  No idea where the luminosity came from.  Perhaps based on the lower distance, perhaps from one of the other references.  I don't think we can use any of it.  Lithopsian (talk) 21:09, 30 December 2020 (UTC)

mass ejection
Per :
 * The findings also indicate that the star [2020fqv progenitor] had a complicated history of mass loss a few years before core collapse. In the years before stars explode, they tend to become more active. Some astronomers point to the red supergiant Betelgeuse, which has recently been belching significant amounts of material, and they wonder if this star will soon go supernova. While Foley doubts Betelgeuse will imminently explode, he does think we should take such stellar outbursts seriously.

Is that info about mass ejection from Betelgeuse more recent than what's already in the Betelgeuse article? Maybe an update is needed. 2601:648:8202:350:0:0:0:D4A (talk) 06:34, 28 October 2021 (UTC)

2022 research on age of Betelgeuse
Colour evolution of Betelgeuse and Antares over two millennia, derived from historical records, as a new constraint on mass and age | Monthly Notices of the Royal Astronomical Society | Oxford Academic (oup.com) https://academic.oup.com/mnras/article/516/1/693/6651563?login=false

This paper discusses among other things a fairly significant revision for age (14 Myr vs. the 8-8.5 Myr in the article from the 2017 research paper), as well discussion around mass and apparent color changes. The change in age is quite significant, I wonder if this merits an edit for the starbox as well as the sections "Main sequence", "Distance measurements", "Variability"? 91.157.47.32 (talk) 07:25, 7 September 2022 (UTC)

the tenth-brightest star in the night sky - incorrect
Betelgeuse is the 10th brightest star in the sky including the Sun. If we consider the night sky, it is the 9th brightest star, excluding the Sun. So correction needed in the 1st paragraph.

N Sanu / എന്‍ സാനു / एन सानू 07:27, 9 February 2023 (UTC)


 * The list article (linked in the lead) shows Betelgeuse as the 10th-brightest in the night sky. Other sources may differ, but you'll need to show them.  Betelgeuse is also variable over a fairly large range and may be anything from about 5th to 20th brightest at any particular time.  Lithopsian (talk) 16:54, 9 February 2023 (UTC)


 * It seems strange to me that the article claims a fairly precise ranking given Betelgeuse's variability. Perhaps something less precise would make more sense? TowardsTheLight (talk) 20:03, 9 February 2023 (UTC)
 * The body of the article discusses that, at extremes, it can be the 6th-brightest or 20th-brightest. We should summarise that in the lead in some way that is concise, not too detailed, but not misleading.  It could be argued that the current lead fails on one count by being misleading.  Lithopsian (talk) 21:39, 9 February 2023 (UTC)

Daily brightness watch - BetelBot
Currently at 156% normal brightness and rising. See the Betelgeuse Status bot on Twitter. Tayste (edits) 20:41, 27 April 2023 (UTC)