Talk:Gamma Andromedae

Name

Hinckley says nothing about "desert lynces", he speaks about badgers. A pity my Arabic language lacks too much! Said: Rursus (☻) 18:12, 8 November 2008 (UTC)

According to Kunitzsch and Smart (A Dictionary of Modern Star Names, p. 15): "The formation of this name [Almach] begins with the ind-A [indigenous Arabic] name for this star: anaq al-ard, "the Caracal" (a black-eared feline predator found in the Middle East)." Spacepotato (talk) 21:42, 31 December 2008 (UTC)

My source says - "Gamma Andromedae was known to the Arabs as 'Almach.' Allen tells us this name was derived from a phrase meaning a small predatory mammal similar to a badger." From P. 27 of Star Lore of All Ages by William Tyler Olcott, G.P. Putnam's Sons, New York and London, The Knickerbocker Press, 1911 - The Allen he speaks of is Richard H. Allen - Author of "Star Names and their Meanings" Moonbug (talk) 07:05, 10 July 2009 (UTC)

The 1842 discovery that gamma2 Andromedae is itself double was, in fact, made by Otto Struve (Struve II), not his father F.G.W. Struve (Struve I), with the Pulkova 15-inch Merz refractor and the subsidiary system = gamma And.BC is accordingly referred to in double-star literature under Otto's catalogue-number of STT 38; according to the listing in Crossley, Gledhill and Wilson's 1879 'Handbook of Double Stars', pge 196, it was Struve I,nevertheless, who made the first measure of this pair, at a then separation of 0.51 arcsec., in mid-September 1842. Always a difficult pair to resolve even at its widest separation of about 0.6 arcsec, thanks to the pronounced inequality of a full stellar magnitude in the light of the two components, STT 38 is now entirely out of reach of direct telescopic resolution as it sweeps in to periastron, and will remain so until 2025 at least. It should be noted that this system is not a Dorpat discovery as seems frequently, and mistakenly, to be supposed.     Christopher Taylor, Hanwell Community Observatory86.134.92.224 (talk) 15:32, 10 October 2011 (UTC)

Have just returned to this page and surprised to find the above, having completely forgotten about it! It should also be pointed out that gamma And. A-BC itself was originally discovered as a double star by CHRISTIAN Mayer in 1777, not by the completely unrelated Johann Tobias who did no work on double stars and had died in 1762. This unfortunate error has now been copied on practically every web-listing of the system I have seen and you would be doing a public service if you corrected the main page-entry accordingly. For a fairly detailed account, with full references, of the history and current situation regarding this double star see my paper in the June 2020 issue of the BAA Journal. gamma BC = STT38 is now at 0.27 arcsec separation and just beginning to appear slightly elongated ('olive') at high power in a 12-inch telescope on a good night.

                                                                          Christopher Taylor (as above) 16.1.212A00:23C7:91A6:3601:F12D:FBAA:D23C:DADB (talk) 15:40, 16 January 2021 (UTC)

Apparent Magnitude

The citation used for γ¹ Andromedae's apparent magnitude records it as 2.1, but this Wikipedia article reports it as 2.26. — Preceding unsigned comment added by 47.184.62.44 (talk) 13:28, 29 October 2016 (UTC)

fixed --Alexander Vasenin (talk) 20:39, 6 July 2018 (UTC)

Simbad is not a reliable source for most things. It changes, as new research becomes available. Better to use the underlying source, which Simbad usually links to, then it is at least verifiable. It can always be changed later if someone decides a better source is now available. 2A02:C7F:7428:D200:5579:F899:C26F:6A95 (talk) 10:31, 7 July 2018 (UTC)

External links modified

Hello fellow Wikipedians,

I have just modified 2 external links on Gamma Andromedae. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

• Added archive https://web.archive.org/web/20060220125558/http://ad.usno.navy.mil/wds/wdsnewweb1.txt to http://ad.usno.navy.mil/wds/wdsnewweb1.txt
• Added archive https://web.archive.org/web/20060220125558/http://ad.usno.navy.mil/wds/wdsnewweb1.txt to http://ad.usno.navy.mil/wds/wdsnewweb1.txt

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Y An editor has reviewed this edit and fixed any errors that were found.

• If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
• If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 15:56, 10 October 2017 (UTC)

External links modified (January 2018)

Hello fellow Wikipedians,

I have just modified one external link on Gamma Andromedae. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

• Added archive https://web.archive.org/web/20141016032204/http://www.astrodwarf.com/star/detail/6724 to http://www.astrodwarf.com/star/detail/6724

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Y An editor has reviewed this edit and fixed any errors that were found.

• If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
• If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 12:36, 23 January 2018 (UTC)

Orbital Period

So the orbital period of B with C is about 64 years, but what is their period around the primary A? Would be good to know that when I'm showing off the pretty double, but I'm having trouble finding it. Pekoebrew (talk) 19:27, 12 November 2019 (UTC)

Several thousand years, but that's just a rule of thumb based on Keplerian motion. No orbit is known because too little orbital motion has been observed. The Tokovinin's Multiple Star Catalogue states 4,748 years. Lithopsian (talk) 20:48, 12 November 2019 (UTC)

Thanks Lith. Yes I see that in Tokovinin's, although I agree it can't be nearly so accurate. Is there some source that gives several thousand years? I think that should be in the article, because I know that people are being confused by the 64 year period mentioned, thinking that's for the two easily visible components. Pekoebrew (talk) 01:41, 18 November 2019 (UTC)

I have added the 4,748 orbital period for the easily visible components. I deemed this necessary, because showing only the B-C orbital period of 64 years was confusing. Feel free to tweak my edit; I'm a beginner with the starbox feature. Pekoebrew (talk) 16:03, 19 November 2019 (UTC)

Hi Lith, I like what you did with my edit, thanks! Then you got inspired to tweak lots of other stuff, eh? I'm sure it's all good, but one nitpick: the two starboxes now have different widths. Looks a bit odd.. Pekoebrew (talk) 07:32, 20 November 2019 (UTC)

The two starboxes is a mess and something needs to be done, just not sure what. They used to be in a single starbox and got split. Maybe needs to go back, even though three/four stars is a lot to take in. Normally, this sort of visual double would get two articles, but these stars are very close together and physically related so not such a good idea. I might come back to it when I get time. Lithopsian (talk) 21:44, 20 November 2019 (UTC)

Thanks. I rather like the Castor starbox, maybe that could be a model? Pekoebrew (talk) 19:25, 22 November 2019 (UTC)

Mass Discrepancy and general inaccuracies

The infobox states that the star has a mass of about 24 solar masses, but stars of that mass do not become Asymptotic Giant Branch stars. This is a major discrepancy that needs immediate change and is very important to the factual accuracy of this extremely flawed page. In addition, the orbital graph is wrong as it shows components Ba and Bb as orange and yellow, but they are instead both blue-white. This page must undergo a large amount of reconstruction before it is factually correct. Could someone help assiti with this problem? 2003 LN6 (talk) 03:50, 1 December 2023 (UTC)

Agreed, some inconsistencies there. I note that the reference (3) for "evolutionary stage following the asymptotic giant branch" does not actually mention γ1 And, the star in question. Yes the orbital graph looks wrong, perhaps could prevail upon the editor who created it? Assambrew (talk) 21:30, 1 December 2023 (UTC)

I have contacted the editor who created the diagram, and suggested changes. We'll see if he responds.Assambrew (talk) 18:58, 2 December 20 23 (UTC)

The maker of the diagram came up with a new version which shows the components with correct colors. I have placed it in the article. Assambrew (talk) 05:06, 4 December 2023 (UTC)

Been looking into the other discrepancies. It appears two different journal articles were cited in good faith, but the articles implicitly contradict each other. Probably the two sets of authors should have gotten their heads together. In any case, one article's title refers to "candidate" post-AGB stars, so we can point out that the A star was considered a candidate, and then mention the mass problem. I'll try to do some editing shortly. Assambrew (talk) 04:11, 7 December 2023 (UTC)

Edits done, I hope that solves the discrepancy issues. If no further discussion, I will remove the disputed tag soon. Assambrew (talk) 04:50, 7 December 2023 (UTC)

Made a couple of small edits to make the properties section a little bit more concise. I couldn't find a source to back this up, but based on its mass I think γ1 And is most likely in a transitional phase between a red and yellow supergiant rather than post-AGB. Carnifex33 (talk) 16:47, 10 December 2023 (UTC)

I removed the mass of 23 M_☉ because it is a very high overestimate and is obviously inaccurate, a calculation with the star's surface gravity, radius and mass (all in Earth units) give a much more consistent mass of 3.7 M_☉, but it can't be added to the article. InTheAstronomy32 (talk) 16:40, 31 May 2024 (UTC)

Distance Discrepancy

Is the distance 350LY (intro), or 390LY (A-table) or 260LY (B-C-table)?! I imagine inconsistency is due to contradictory sources. Incidentally nice photo here by Damian Peach, stark colors and the second B-C double. Tom Ruen (talk) 21:39, 6 August 2024 (UTC)

The 350 is a holdover from an older parallax value. I've updated the lead to match the Hipparcos distance for the primary. The secondary parallax is probably more reliable, but it is for a pair and is is unclear how closely it corresponds to the actual distance of the primary. So 390 it is, pending more data. Lithopsian (talk) 21:21, 8 August 2024 (UTC)

Yes that is a nice photo showing the multiple stars. I got Damian Peach to do a copyright release, and added it to the article. Assambrew (talk) 18:24, 24 October 2024 (UTC)

Mass of Almach

Hey @Lithopsian@21.Andromedae, What is the mass of star Gamma¹ Andromedae. I am hearing it's around ~20 ish M_☉. Abdullah1099 (talk) 06:01, 29 April 2026 (UTC)

The answer might be in the "Mass Discrepancy and general inaccuracies", and is somewhat unfun: Its mass is unknown, and i can't find any reasonable value that could be cited. However, this paper says that Gamma Andromedae B is one of the few systems where individual masses and radii, along with the distance, can be dynamically determined, so if a paper is someday published with properties for Gamma Andromedae B, it might include properties for Gamma Andromedae A too. 21 Andromedae (talk) 09:55, 29 April 2026 (UTC)

MSC gives a mass that should be enough to go in the article, although it is a fairly crude estimate. Too high for a post-AGB star, but the post-AGB status itself isn't well-supported by other sources. This paper includes it in a list of red supergiants with B companions, although published spectral classes are almost universally giant or bright giant. Tetzlaff gives an even higher mass, plus an age. I think I'll be updating the properties a bit when I'm done digging. Lithopsian (talk) 14:46, 29 April 2026 (UTC)

The classification as a candidate post-AGB star appears to originate from this paper. That classification is rather loose, basically high(-ish) luminosity, low-surface-gravity stars at high galactic latitude. On that basis, or even if the star is not post-AGB but has the luminosity shown in the article, it doesn't really look like a 15-20 M_☉ star. Lithopsian (talk) 15:06, 29 April 2026 (UTC)

Yeah, I also think based on all details. I think a solar mass MSC of 14 would be more likely and i think 23 is bit too much. But i think an approx estimated mass should be added with respective citations Abdullah1099 (talk) 15:49, 29 April 2026 (UTC)

I would keep the current article without any mass estimate for now. A star with such a mass would be expected to be a white to blue supergiant like Arneb, Rigel, Canopus, HT Sagittae, not a K-type giant. As i commented in a section above, the radius and surface gravity would give a mass around 3.7 M_☉, but it combines measurements from two different sources and therefore can't be added. 21 Andromedae (talk) 15:59, 29 April 2026 (UTC)

Ok, I understood what is the problem with this star. I am also ok but atleast some information should be given on the mass of the star in the article bro. But i want to know the mass is calculated Abdullah1099 (talk) 16:01, 29 April 2026 (UTC)