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There is a "Error: No valid link was found at the end of line 22." error in the page. — Preceding unsigned comment added by 65.9.224.15 ( talk) 23:08, 7 May 2013 (UTC)
Fictional information of this nature can be added to Galaxies in fiction, which is linked from the "See also" section.— RJH ( talk) 17:59, 11 July 2008 (UTC)
Article currently states that Hipparcos either did not measure Cepheid variable-star distances with reasonable accuracy- or did not measure ANY CEPHEIDS AT ALL. Several dozen Cepheids fell within HIpparcos' effective range of ~100 parsec (a few hundred light years). Of those, a dozen or so were quite close, measured with strong S/N multiple times.
One possibility is that some editor is so grossly ignorant of distance measurement that she believes Hipparcos must measure Cepheids located inside Andromeda. This is, frankly, a shocking degree of misinformation. A quick read of the Hipparcos or Cepheid articles will illustrate the measurement method, but I'll summarize just to be thorough. Hipparcos CALIBRATES Cepheid distances; Andromeda Cepheids can then be observed with HST, Keck I/II, Gemini N, etc. —Preceding unsigned comment added by 12.176.210.201 ( talk) 00:03, 7 June 2009 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
GA review – see WP:WIAGA for criteria
I addressed the main concerns regarding citations, though part of that included removing the table, as I can see no reason for an arbitrary portion of the table on the main page about Andromeda's satellites to have been copied on to the page for Andromeda. I'll try to address the issue of citations there anyway, but I think the main concerns you raised for the article as it stands have been addressed.
James McBride (
talk)
09:28, 12 July 2009 (UTC)
22:03, 7 July 2009 (UTC)
This line of the article is possibly plagiarised. More importantly, where can we find a description of this elegant and simple method (which supposedly was far more accurate than Hubble's and is still used)? Cesiumfrog ( talk) 06:10, 30 January 2011 (UTC)
(quote from the article): rotational velocity climbs to a peak of 225 kilometres per second (140 mi/s) at a radius of 1,300 light-years (82,000,000 AU), then descends to a minimum at 7,000 light-years (440,000,000 AU) where the rotation velocity may be as low as 50 kilometres per second (31 mi/s). (end quote)
If one calculates the accelleration at 1,300 lightyears which is needed for a roatational velocity of 225 km/s (4,11E-09 m/sec2) the mass wich would cause this is 9,34E+39 kilo~ If one calculates the acceleration this mass causes at 7,000 lightyears one gets 1,42E-10 m/sec.
If however one calculates the acceleration at 7,000 lightyears for a rotational velocity of 50 km/s this is only 3,77E-11 km/sec2, 25% of what it should be. Do we have negative dark matter here, or has someone messed up the data? I suspect the latter Velzen5 ( talk) 11:25, 27 March 2011 (UTC)
The gxy has an active galaxy nucleus (AGN - Y1O-TLA) per SIMBAD and per Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010) (at VizieR). More specifically it is a "LINER-type Active Galaxy Nucleus" (or whatever) acc2 SIMBAD. FYI. Rursus dixit. ( mbork3!) 13:34, 4 April 2011 (UTC)
I just imported this excellent picture (bottom image on right) from Flickr, and wondered whether anyone objected to using it as the lead image in the article. It's of a higher resolution, has a wider field of view and is more aesthetically interesting than the one we're using at the moment. However, it includes h-alpha, so thought it would be sensible to propose the change here first in case there is consensus that the current version has more encyclopedic value. NotFromUtrecht ( talk) 20:42, 10 January 2011 (UTC)
I am just wondering why this image had not been flipped? it is showing Andromeda how it appears through an uncorrected Telescope. do we print pictures of people upside down when taken through a lens? no we correct them and print the image so it looks as it should to the human eye. you have over 100 pages linking to this image and if you look at the image below (above on the main page) on this page you will see you have 2 images of Andromeda, one corrected and the other not its traveling in 2 different directions, one will miss the milky way, then other will collide with it in 4.4 billion years. Samantha.pia ( talk) 17:01, 11 April 2011 (UTC)
The apparent magnitude of the Andromeda Galaxy is given as 3.4 and 4.4. The latter seems to be correct. —Preceding unsigned comment added by 93.97.55.83 ( talk) 10:13, 6 September 2008 (UTC) The magnitude is still given as 3.4, 3.44 and 4.36. The 4.36 is in note b. — Preceding unsigned comment added by 93.97.194.200 ( talk) 12:07, 13 July 2011 (UTC)
The following uncited claim needs clarification: "[Isaac] Roberts mistakenly believed that M31 and similar spiral nebulae were actually solar systems being formed, with the satellites nascent planets" This is not stated in either the Isaac Roberts article or in the articles on the history of exoplanets or the correct terminology - planetary system. The only reference I can find is in a student publication http://messier.seds.org/xtra/Bios/roberts.html "In 1888, he obtained a photograph of the Andromeda Nebula M31, well showing its spiral structure. Roberts believed that M31 and other spiral "nebulae" were solar systems in formation, with the satellite galaxies M32 and M110 being planets in formation", however there are no inline citations and the references listed appear not to support this. I really think this claim needs to be substantiated or removed from the article. -- EvenGreenerFish ( talk) 23:33, 2 April 2012 (UTC)
Isn't the future collision also called into doubt by the accelerating universe observations? If I understand the margin of error on the measurements is such that Andromeda Galaxy might never collide, and instead be the last galaxy to disappear from our view. Bill C. Riemers ( talk) 14:25, 12 December 2011 (UTC)
Another point of interest. In the advent of a collision what would be the effect of the gamma ray bursts from the Andromeda Galaxy super massive black holes, as the Andromeda Galaxy passed through the Milky Way Galaxy? Bill C. Riemers ( talk) 14:25, 12 December 2011 (UTC)
Can someone add the latest information about this future collision? See NASA's Hubble Shows Milky Way is Destined for Head-on Collision with Andromeda Galaxy. Also M33 seems to be involved in the collision. 83.83.36.26 ( talk) 20:58, 31 May 2012 (UTC)
I've found in other sources like this paper or M31's entry on HyperLeda different apparent magnitudes for this galaxy. Would be wise to include them?. U-95 ( talk) 00:38, 29 July 2012 (UTC)
I know you mentioned "consumed by M31 in the past" But also please mention the date which was 200 mya. Also why didn't you mention the evidence for the collision with M32, the hole picked up by infra rays. — Preceding unsigned comment added by Anastronomer ( talk • contribs) 06:23, 20 October 2012 (UTC)
I aplogize, I didn't realize that you put the date. — Preceding unsigned comment added by Anastronomer ( talk • contribs) 19:50, 20 October 2012 (UTC)
This is ofcourse a load of bs. It was there in the sky for everyone to see for 1.000.000's of years.. crediting its discovery to anyone is just plain nonsense. You cant credit anyone with discovering the atlantic ocean either.
This claim is false "The Roman poet Avienus wrote a tantalizing line about the chained constellation in the 4th century AD.[14] who described it as a "small cloud" in his Book of Fixed Stars." Avienus never said that, it was in fact Abd al-Rahman al-Sufi. Even if you click on the link of the book, it states that HE is the author and HE is the one quoted saying that. Check other sources as well. I will make the correct change. (
Parmis17 (
talk)
08:05, 14 November 2010 (UTC))
Actually the planet Uranus "was there in the sky for everyone to see" for millions of years too - it can sometimes be seen with the naked eye as a sixth-magnitude 'star', and we know it was observed sometimes (listed in 18th century observation logs and so on). That doesn't mean anyone did spot it as noteworthy before Herschel in 1781. You have to realize that the Greeks and Romans were much less interested in weak, fuzzy, cloud-like objects in the sky than some medieval and (especially) post-Kepler astronomers would be. The idea of the stars as lit points on a firmament globe, all at the same distance from earth and all eternal, gave no particualr place for nebulas and the like, they would just have been seen as odd and inconsequential scrap on the pureness of the sky. 83.254.151.33 ( talk) 05:08, 18 November 2012 (UTC)
in the opening paragraph. Fourtyearswhat ( talk) 19:36, 19 September 2008 (UTC)
It'll be the end of Andromeda Galaxy, as Milky Way will swallow Andromeda Galaxy, Milky Way is about 40% larger than Andromeda Galaxy...THIS IS WRONG
—Preceding
unsigned comment added by
88.109.209.213 (
talk)
01:35, 15 April 2009 (UTC)
In the context of the Big Bang theory, why would another galaxy be approaching our Milky Way galaxy at one-thousandth the speed of light, 300 km/sec.? Larry R. Holmgren ( talk) 19:36, 29 February 2012 (UTC)
Another inconsistency: If the Andromeda galaxy is approaching us at 300 km/sec (i.e. 0.001 c), then assuming it didn't accelerate as it gets closer, which it will) this gives an upper bound on the time to collision of 1000 x the current distance separating our galaxies in light years, which is quoted in the intro paragraph at 2.5 million light years, i.e. 2.5 billion years to collision. The number quoted in the second paragraph says this collision will occur in 3.75 billion years. This value is clearly way too high. I've seen all sorts of numbers for this time to collision quoted, but not a single calculation. All of this is readdressed in the last section which quotes an approach speed of only 100-140 km/sec vice 300 km/sec quoted previously. This value range makes the previous time to collision more reasonable, however this section pulls another time to collision value (450 billion years) out of the air which is inconsistent with the previous value. It would be nice to make all of these numbers more consistent with each other. — Preceding unsigned comment added by 74.96.159.30 ( talk) 18:03, 26 November 2012 (UTC)
Hubble's distance measure was 275 kpc, Opik's 450kpc. The Actual distance is around 800kpc. Given this, how is it that Hubble 'settled the debate'? — Preceding unsigned comment added by 81.99.233.105 ( talk) 12:32, 3 May 2013 (UTC)
The blueshift speed may need to be updated to 300 KM/Second Per search results at The NED galaxy database. I would like to gain consensus before i make the edit. Here is the reference for further examination. To prevent confusion, The Andromeda Galaxy is also known as Messier 31 (M31).-- Anderson I'm Willing To Help 21:11, 16 July 2013 (UTC)
Comment: it is currently described in the article that the galaxy itself is currently on a blueshift, However, the blueshift velocity is not sourced, or, contains a dead source.
Anderson
I'm Willing To Help
03:44, 17 July 2013 (UTC)
Info has been cited. Reference has also been fixed. Cheers,--
Anderson
I'm Willing To Help
21:19, 18 July 2013 (UTC)
As the Andromeda Galaxy is larger than the Milky Way and contains many times more stars, how can it be lighter? -- KnightMove ( talk) 10:25, 12 July 2012 (UTC)
I've always thought that andromeda was the closest galaxy to our own, but the intro implies that it is merely the closest spiral galaxy to ours. Can someone verify this? Thanks! M00npirate ( talk) 01:31, 16 December 2008 (UTC)
The Andromeda Galaxy is the nearest galaxy that is not a Dwarf Galaxy. Of course the Large Magellanic Cloud and the Small Magellanic Cloud are closer, But they are dwarf galaxies.-- Anderson I'm Willing To Help 21:53, 21 July 2013 (UTC)
Are there extra-terrestrial lifeforms, more specifically intellegent lifeforms in the Andromeda Galaxy? — Preceding unsigned comment added by 68.189.186.199 ( talk) 01:59, 16 July 2011 (UTC)
Well, given that there are an estimated trillion (that is, 1,000,000,000,000) stars in it, a reasonable answer would have to be "almost certainly". But now comes the hard part. If you can find indisputable evidence of even one of them, well, your first Nobel Prize would only be the beginning. Old_Wombat ( talk) 10:16, 10 October 2011 (UTC)
Andromeda Galaxy /ænˈdrɒmɨdə/ is incorrect in American English. The vowel in the second syllable should be the low a (not the rounded a in British English). What is the general Wikipedia policy towards these two dialects? Give both? — Preceding unsigned comment added by 24.46.193.105 ( talk) 19:40, 20 April 2014 (UTC)
Please be more specific. In most of N. America (especially Canada), "father" and "bother" rhyme, as in "cot", and the "o" in Andromeda has that sound. Not everyone knows the jargon..."low", "rounded", etc. I think I agree with you, assuming I am guessing your meaning correctly. — Preceding unsigned comment added by 184.147.124.193 ( talk) 22:29, 20 September 2014 (UTC)
>== imposible ==
it is wrong to say that the universe is only 13.8 billion years old if it is true then the speed of light is not constant or was there ever a big bang its all wrong — Preceding unsigned comment added by [[Special:Contributions/([[User talk:|talk]]) 12:36, 26 October 2014 (UTC)
it is wrong to say that the universe is only 13.8 billion years old if it is true then the speed of light is not constant or was there ever a big bang its all wrong — Preceding unsigned comment added by Sabbathart ( talk • contribs) 12:59, 26 October 2014 (UTC)
The infobox at the beginning of the article says that the diameter of the galaxy is ~220 kly, whereas the "recent distance estimate" contains a calculation that indicates a diameter of 141 +/- 3 kly. What is the current best estimate for the diameter according to scientific consensus or official bodies? Could someone edit the article to be internally consistent? Ketone16 ( talk) 22:12, 8 January 2015 (UTC)
Should this image be mentioned in the article? [5] — dv82matt
- I added an external link to: A National Geographic video explaining the NASA image Hubble's image of the Andromeda Galaxy mentioned in the item above. http://video.nationalgeographic.com/video/short-film-showcase/a-hundred-million-stars-in-3-minutes? Jcardazzi ( talk) 12:55, 21 March 2015 (UTC)jcardazzi
From Wikipedia:Rough guide to semi-protection, most of the IP edits this year have been reverted, unreverted IP edits have been minor, reversions are from a wide range of IPs, the traffic seems to be increasing lately, and the majority of the contributions are from registered users. Seems like an easy decision to me, except that I don't know whether the vandalism frequency is high enough to warrant semi-protection. I'll leave that to the admins. ~ Tom.Reding ( talk| contribs| dgaf) 16:02, 16 December 2014 (UTC)
I can't back this up with any sources, but i learned that this object was origanlly named "great nebula in andromeda" and later "galaxy in andromeda". Also, it is the constellation in which this object is located that is named after the princess in greek mythology, not the object discussed here itself. maybe i'm wrong here, but i think it should at least be looked into.
92.116.36.115 ( talk) 04:28, 1 January 2010 (UTC)
I would also like to propose that naming of the object in question be kept consistent throughout the article, unless it is important in a given instance that it varies. Either M31 or Andromeda but having both is mildly confusing until you realize what's going on Dwarfyperson ( talk) 08:01, 14 January 2012 (UTC)
Do you think is worth to add a section describing observations from an amateur POV (when and where she's better seen, what can be spotted with the naked eye/binoculars/etc)? -- U-95 ( talk) 22:19, 4 October 2016 (UTC)
67,450 ± 920 pc makes no sense. It must be 67,450 ± 0,920 kpc
Jonorbe ( talk) 16:53, 6 October 2016 (UTC)
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Can we change "M31" to "Andromeda" is most cases? Right now the article makes mixed use of these two designations, and for some readers this might be confusing.
Isambard Kingdom (
talk) 16:35, 9 October 2016 (UTC)
Done
Isambard Kingdom (
talk)
18:58, 21 October 2016 (UTC)
Please consider adding the following "simulated" photo of the Andromeda Galaxy, which shows what it would look like in our sky if it were only much brighter. Imagine seeing that in the sky every night!
The image of Andromeda Galaxy: https://i.kinja-img.com/gawker-media/image/upload/s--paTMMEl_--/c_scale,fl_progressive,q_80,w_800/19bal4d1p8fncjpg.jpg
From the page: http://sploid.gizmodo.com/the-incredibly-huge-size-of-andromeda-1493036499 [1]
It might need verification from someone knowledgable in astronomy, but this photo is such a dreamy sight I think it would add a lot to the article for people to see what it would ACTUALLY LOOK LIKE if Andromeda were brighter. I like this photo better than any other rendition of the Andromeda Galaxy because of the combination of dark sky, angle of Andromeda, zoom level, and placement only somewhat near our moon.
This photo to me says: our galaxy is not alone.
68.189.37.162 ( talk) 21:36, 17 February 2017 (UTC)
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As a point of historical reference (suggesting some discrepancy in the present article), in 1939 the distance to the 'Andromeda Nebula' was thought to be 210,000 parsecs (680,000 ly) 'from studies of Cepheid variables'. Cf Babcock, Lick Observatory Bulletin#498, 1939
In this article, Horace W. Babcock also observes that 'the nearly constant angular velocity of the outer parts of M31 is the opposite of the 'planetary' type of rotation believed to obtain in the outer parts of the galaxy' ... an early indication of 'dark matter'. Twang ( talk) 23:30, 29 July 2017 (UTC)
Adding this picture here in case it's useful. It was uploaded by the photographer for the Wiki Science Competition in the United States (and was one of the finalists). — Rhododendrites talk \\ 05:35, 26 January 2018 (UTC)
Just came across new research that adromeda is only 110,000 light-years across, roughly the same size as our own galaxy. This article should be revised. NocturnalDef ( talk) 17:26, 15 February 2018 (UTC)
Perhaps I can take to liberty to modify it. It'll be a few days to look up the proper sources however.
nocturnalDEF NocturnalDef ( talk) 18:59, 1 March 2018 (UTC)
According to a recent research by the International Centre for Radio Astronomy Research, the Andromeda Galaxy is roughly the same size as the Milky Way Galaxy. Should we change the size of the Andromeda Galaxy accordingly?
Source: https://www.icrar.org/cosmic-collision/
Original Research Paper: https://s3-ap-southeast-2.amazonaws.com/icrar.org/wp-content/uploads/2018/02/13131736/m31-escape-velocity.pdf
Xindeho ( talk) 15:33, 5 April 2018 (UTC)
ok a sister galaxy to milky way, eaten by andromeda. thats a very big thing, that really existed, and is highly notable. i know we dont know much about it, but i think it deserves an article.(mercurywoodrose) 50.193.19.66 ( talk) 17:29, 23 July 2018 (UTC)
Astronomy Magazine is going on and on about how astronomers have now (finally) discovered that the Andromeda Galaxy does not weigh as much as it once did:
http://www.astronomy.com/news/magazine/2018/02/adromeda-is-the-same-size-as-the-milky-way
What does the actual Science say? I don't think that one single study should trump dozens of previous ones. Does the main article need updating? Jehannette 10:30, 28 July 2018 (UTC)Jehannette
ESA researcher found that the Milky Way is much greater than expected: http://sci.esa.int/hubble/61198-hubble-and-gaia-accurately-weigh-the-milky-way-heic1905/
Should we change the first paragraph? — Preceding unsigned comment added by 2A0A:A540:EE45:0:A537:480:D78:8ABB ( talk) 19:51, 11 March 2019 (UTC)
It would be nice to be able to cite actual publications instead of bare urls. Also, an effort should be made to outline the situation instead of simply replacing the old, well-referenced number by a new number copied off some press release. It is extremely difficult to estimate galaxy masses with any accuracy, and there are different methods which need to be explained. The concept of virial mass needs to be explained. This 2006 paper finds estimates an 8:10 ratio for Milky Way to Andromeda masses. This is compatible with other similar results published during the 2000s. This article needs to figure out how old and how well-established this result is, and if necessary explain that it is outdated, or at least has become less certain than it used to be two years ago.
It appears we have both a 2018 study which lowers the estimated value for the Andromeda Galaxy and a 2019 study which raises the value for the Milky Way. We need some reliable secondary source which puts these two factors in perspective and outlines if and to what extent mainstream opinion has been affected by this. -- dab (𒁳) 11:18, 6 April 2019 (UTC)
Has anyone seen a listing that compares cw and ccw rotating spiral galaxies? It seems like this should be an important statistic to include in articles. Sometimes easy to tell, but for M31, not perpendicular enough for me to be sure. Does anyone know for M31? Any sources? Tom Ruen ( talk) 22:55, 27 April 2019 (UTC)
According to the latest estimations (2012), M31 is located at 766 ±21 kpc or ~2.5 million l.y. In this case, its absolute magnitude listed in your frame at right of you main page cannot be -21.5 but -20.98 (and to get M=-21.5, it means that M31 'd be closer than 2.2 million l.y. was has been invalidated since 1998). You will find additional data at https://www.noao.edu/meetings/m31/files/distance-to-m31.pdf -- luxorion — Preceding unsigned comment added by 2001:7e8:cc44:4200:895a:681:378f:ea04 ( talk) 16:14, 7 May 2018 (UTC)
In the infobox a value is given for the distance that, according to a footnote, is the simple average of 4 published distance determinations. This is a) original research and b) wrong: since some determinations have a better formal accuracy than others, they should be counted with a higher weight when averaging. Also the selection of the contributing values must be justified: the determinations must be independent (e.g. a later one not being in improved value of an earlier one partially based on the same data). I will flag the value; how best to resolve this? Tom Peters ( talk) 12:53, 24 October 2019 (UTC)
It looks like the article has been vandalized by numerous IP Users. One of these saw the removal of the Main Image. WHAT HAPPENED ???????????????????????????? — Preceding unsigned comment added by THE COLOSSAL GALAXY NAMED IC1101 ( talk • contribs) 06:47, 22 July 2020 (UTC)
Ok.... THE COLOSSAL GALAXY NAMED IC1101 ( talk) 00:51, 23 July 2020 (UTC)
Ok. I will try to tell an administrator to semi protect the page. Im sure this is a good article, I don’t want it to become bad. After all PNSMurthy, The Andromeda Galaxy is also my favorite galaxy, Like you. My opinion tells me that it is 261,000 Ly Across !!! THE COLOSSAL GALAXY NAMED IC1101 ( talk) 04:54, 23 July 2020 (UTC)
I have already raised the issue in the teahouse, I was planning to approach an admin myself. PNSMurthy ( talk) 05:34, 23 July 2020 (UTC)
IP Users... They disrupt Wikipedia... I too, was an IP User Named 122.2.30.162. I could not edit the List of largest stars, But I want to revert Nussun 05’s String of adding inaccurate Sizes, which has stopped very recently. I instead wanted to have an edit request to remove inaccurate sizes so I created Stop adding inaccurate sizes because of this. Now I have an account about astronomy with 340 plus edits. It is soon hopefully reaching 400 then 500 edits and I have already exceeded a few users . THE COLOSSAL GALAXY NAMED IC1101 ( talk) 16:25, 23 July 2020 (UTC)
Under Mass estimates can we add an actual estimate for the dark matter mass in the galaxy or its halo. Or do the sources not calculate this ? - Rod57 ( talk) 12:11, 30 April 2021 (UTC)
Is definitely name after an ETHIOPIAN princess. What version of The Odyssey have you read where it says Phoenician ? Paragraph 3 line ONE it clearly says αἰθίοπας, or Aithiopas, Ethiopia, or Black Skinned, Kushite. Allanana79 ( talk) 23:47, 5 June 2021 (UTC)
I do not know where to find the proper swift tour or how to link to it but perhaps someone can fix it. User random numbers ( talk) 00:52, 20 May 2022 (UTC)
Okay, I'll get straight to the point. Citing this source [2] from 2006 by Chapman et al, the article says this:
In 2005, astronomers used the Keck telescopes to show that the tenuous sprinkle of stars extending outward from the galaxy is actually part of the main disk itself.
Except it doesn't? Nowhere in the paper does it say that the halo of Andromeda belongs to the stellar disc, more so that it was the delimitation of its extent. In fact, looking at the press release document, they said this:
In addition to being metal-poor, the stars of the halo follow random orbits and are not in rotation. By contrast, the stars of Andromeda's visible disk are rotating at speeds upwards of 200 kilometers per second.
So, here's the thing. I've been working on an article related to galaxy sizes for quite a while now, so I think I should give my views. Haloes, the "tenuous sprinkle of stars", or any diffuse protrusions (such as radio jets) are almost never used in the literature to define the size of a galaxy (as stated in Talk:IC 1101 where this became an issue). From the bit of sources I can find, galaxy sizes are almost always defined via isophotometry in optical/near infrared, fractional light radius (half-light, and others use 90% light), Petrosian radii, or scale lengths (logarithmic luminous flux, I think, where light is ~2.718 times less the nucleus). If you are using NED for a while, they mostly use the first two (because they give the largest diameters).
Speaking of NED, they give a physical size to Andromeda here to be about 46 kpc (150,000 light years), via the B-band isophote in RC3. 2MASS gives an almost similar diameter. But the 220kly value has been gone for quite a long time now, so I am too afraid to edit it without consulting it here first. Either way, thoughts? SkyFlubbler ( talk) 18:01, 16 July 2022 (UTC)
References
Looking at a few of the easiest sources to access, I get the impression that capitalizing "galaxy" is not preferred, likely because it's not actually part of the name. I don't see that this has been raised in the past, and I can't easily access many of the sources, which is why I am looking for discussion about whether this might need to be renamed. ~ T P W 16:44, 23 November 2022 (UTC)
https://www.astrobin.com/1d8ivk/ https://iopscience.iop.org/article/10.3847/2515-5172/acaf7e
It appears a new emission arc was detected around and inside Andromeda. Note worthy for the page? Could probably be a good image in that Astrobin article to throw in as well. Mrblue630 ( talk) 18:54, 9 January 2023 (UTC)