The following is an archived discussion of a featured article review. Please do not modify it. Further comments should be made on the article's talk page or at Wikipedia talk:Featured article review. No further edits should be made to this page.

The article was kept by Nikkimaria via FACBot (talk) 1:03, 4 February 2023 (UTC) [1].

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Notified: DarkHorizon, Serendipodous, Kheider, Nrco0e, Kwamikagami, Eurocommuter, Ruslik0, JorisvS, WolfmanSF, WikiProject Solar System, WikiProject Astronomy, WikiProject Astronomical objects, WikiProject Spoken Wikipedia, 2022-04-03

I am nominating this article for review because this 2010 featured article is not up to standards anymore. The problem is mainly with FA criteria 1b and 1c ("comprehensive" and "well researched").

The vast majority of the article is between 12 and 14 years old, which is an eternity, both in astronomy and in Wikipedia history. Our understanding of Trans-Neptunian Objects in general has evolved a lot. To give just one example, most of the "classification" section was written in 2008, and some of it is obviously outdated. For instance, the sentence "no other objects have yet been discovered in its vicinity" (introduced in this edit on 16 February 2008) is wrong since 2012 VP113 was announced in 2014. While some errors like this are easy to correct individually, they are a symptom of the article's overall lack of maintenance, accumulated over the past decade. I raised the issue on the article talk page a month ago, but got zero responses.

A minor issue I have raised in my most recent post on the article talk page is the lack of a section dedicated to observations, see Talk:90377_Sedna#No_"observations"_section? Renerpho (talk) 05:41, 3 May 2022 (UTC)[reply]

One thing I'd like to add: Following my last FAR nomination, which went over my head, I was uncertain about whether to raise this issue at all. I decided to go ahead, but I don't know how much I can contribute. I do have some expertise about the subject (more so than for the topic of the last FAR), which I am willing to offer, but I invite the users I notified to assist, if they can. Renerpho (talk) 05:41, 3 May 2022 (UTC)[reply]

One more thing - I have not corrected the issue mentioned above ("no other objects have yet been discovered...") because, even though I assume that this may be an easy one to correct, I was waiting for input on the talk page, which there wasn't. I didn't know how to correct it a month ago and I don't know now. Renerpho (talk) 05:56, 3 May 2022 (UTC)[reply]

Close without FARC. I'm not so convinced by the nominator's argument. Looking at the article, it seems like it's in pretty good shape. We haven't learned a whole lot of new things about Sedna since it was promoted to FAC in 2010. The biggest developments have been the discovery of a few other similar objects as well as Sedna's relation to the Planet Nine hypothesis, both of which are already included in the article. The statement "no other objects have yet been discovered in its vicinity" is in relation to Sedna's specific orbit with regard to whether it could be considered a planet, not with regard to other similar objects in general. That seems like a fair statement given that the other similar objects are not really in Sedna's vicinity, at least not compared to Pluto and its nearby KBOs. Some of the observations of Sedna after its discovery are already mentioned in the physical characteristics section when such observations were responsible for the discovery of new information about Sedna. I don't think it's really necessary to include other post-discovery observations that didn't help us learn more about Sedna. Sportsfan77777 (talk) 16:48, 6 May 2022 (UTC)[reply]

• Concern - the thing that sticks out to me is that the article isn't quite sure what 90377 Sedna is. The first sentence of the article states directly "Sedna (minor-planet designation 90377 Sedna) is a dwarf planet " but the classification section states that the official classification body considers it to be a "scattered object", but also says that some consider it a new class of object, and that it is also expected to meet the requirements to be a dwarf planet and that some have called it such. So the lead calls it a dwarf planet but the article body suggests that there's much disagreement about classification? Additionally, "Such a mission could be facilitated by Dual-Stage 4-Grid ion thrusters that might cut cruise times considerably if powered, for example, by a fusion reactor" looks like original research, unless the source specifically discusses a mission to Sedna; this is sending off strong original research warning signs because the "such a mission" referred to was proposed in 2018, while the source for that sentence is from 2009 so it's clearly not directly referring to the proposed mission. Hog Farm _Talk 17:57, 6 May 2022 (UTC)[reply]
  • It's both a "dwarf planet" and a "scattered disc object", the same way Pluto is both a "dwarf planet" and a "Kuiper Belt object", but "dwarf planet" is clearly the primary classification in both cases. "Dwarf planet" is what it is, and "scattered disc object" is where it is. However, based on where it is, it's not really clear it should be considered a "scattered disc object" and might be better considered an "inner Oort Cloud object". There is no concretely accepted answer, and that is discussed in the article. Sportsfan77777 (talk) 19:03, 6 May 2022 (UTC)[reply]
    • One correction: It looks like the Minor Planet Center doesn't list Sedna as a "scattered disc object" anymore. Still, I don't think there is so much to change because the article already presented that it wasn't really a scattered disc object. Sportsfan77777 (talk)
      • Any idea where to find what (if anything) the MPC classifies Sedna as these days? @XOR'easter:? This looks fairly easily savable to my layman's eyes, so hopefully we can get this one pushed over the line. Hog Farm _Talk 20:00, 6 May 2022 (UTC)[reply]

      As far as I can tell, they just list it as a transneptunian object [2]. XOR'easter (talk) 00:24, 7 May 2022 (UTC)[reply]

      • Sedna was listed as a SDO at [3], but this is no longer the case. Renerpho (talk) 02:42, 7 May 2022 (UTC)[reply]
  • There is no official proposed mission. They are both talking about it hypothetically, albeit separately. You could go with "This type of mission" instead of "Such a mission" to better separate the two? Sportsfan77777 (talk) 19:03, 6 May 2022 (UTC)[reply]
    • I think this would probably be an improvement. Hog Farm _Talk 20:00, 6 May 2022 (UTC)[reply]

Comments by Renerpho Thanks for the comments, which sound encouraging so far. Below are some points, with details of where the article may no longer be in line with recent results. I'm sorry I didn't put these into the original nomination, but I have not yet been able to fully review the article. If someone with expertise in the topic could help with adding points that are outdated, I'd appreciate it! The points below are mostly about the "classification" section.

• As noted, the classification isn't straight-forward (for example, the dwarf planet classification is at odds with the "official" IAU status, compare Talk:90377_Sedna#Sedna_is_not_a_dwarf_planet_according_to_the_IAU). I think there is room for improvement when it comes to how Wikipedia handles these cases in general, but so far, the Sedna article seems to be in line with what we do elsewhere. No action about this is needed in the Sedna article, as far as I am concerned.
• Johnston's Archive, which is used in some similar articles ((589683) 2010 RF43, for example) classifies Sedna simply as a sednoid.[4] Should we add that as an additional source?
• Regarding the lack of objects in Sedna's vicinity, I think the claim at least requires a reference that says what it actually means. I am uncomfortable with solely relying on your (reasonable) interpretation, Sportsfan77777, especially since the sentence was added when my interpretation would have been purely hypothetical.
• Caltech researchers Konstantin Batygin and Brown have hypothesised the existence of a giant planet in the outer Solar System, nicknamed Planet Nine. - The numbers in that section (mass, orbital period) don't reflect the latest results by Batygin&Brown, compare the Planet Nine article. Should we update this?
• To be a dwarf planet, Sedna must be in hydrostatic equilibrium. It is bright enough, and therefore large enough, that this is expected to be the case. - The reference for this is (Brown, 2008), which is fairly old, and determining whether something is in hydrostatic equilibrium was thought to be easier at the time. Brown's "dwarf planet census" seems to have fallen out of favour recently, because it is no longer in line with scientific consensus. See Talk:List_of_possible_dwarf_planets#Is_there_some_reason_why_we_still_keep_Brown's_values? for a discussion. It turns out that this is complicated (for a recent related discussion of the possible shortfalls of what "hydrostatic equilibrium" means, see Talk:List_of_possible_dwarf_planets#Is_the_Moon_in_hydrostatic_equilibrium?). An additional problem is that the size at which an object is expected to be in HE depends on its composition. In 2019, Grundy et al. found Sedna to likely be in HE, but also that many objects with diameters of 400-1000 km (Sedna: ca.1000 km) have densities that don't seem to allow for them to be in HE.^[1] Compare the discussion at List_of_possible_dwarf_planets#Grundy_et_al.’s_assessment. Sedna's density remains unknown.
• and several astronomers have called it one - That's nice, but none of the cited references is younger than 10 years. We can add Grundy from 2019, but it would be nice to have additional recent sources. I'll see if I can find any. Maybe someone can have a look, too?
• What about the addition of an "observations" section? I see one reply above that argues against it, and one on the article talk page that is in favour of the addition. Renerpho (talk) 02:31, 7 May 2022 (UTC)[reply]

@Renerpho: it would be nice to have additional recent sources. User:Double sharp found several from this year and last: [5], [6], [7], [8]. Though the 400k limit in the 2nd is obsolete. — kwami (talk) 21:38, 22 June 2022 (UTC)[reply]

• Could we get an update on status here? Nikkimaria (talk) 02:32, 28 May 2022 (UTC)[reply]

I've updated the Planet Nine numbers and made some other small emendations. XOR'easter (talk) 17:59, 26 June 2022 (UTC)[reply]

I think the concerns raised above have been addressed. XOR'easter (talk) 19:35, 29 June 2022 (UTC)[reply]

Needs closer scrutiny, samples only from only looking at one small section:

• Cited to 2010 archive.org ... Although Sedna is listed on NASA's Solar System exploration website,[83] NASA is not known to be considering any type of mission at this time.[84] Update ???

  Removed. XOR'easter (talk) 05:51, 11 July 2022 (UTC)[reply]

• Passive voice, cited to 2011, update ? It was calculated that a flyby mission to Sedna could take 24.48 years using a Jupiter gravity assist, based on launch dates of 6 May 2033 or 23 June 2046. Sedna would be 77.27 or 76.43 AU from the Sun when the spacecraft arrived near the end of 2057 or 2070, respectively.[85]
• WP:FORBESCON, not reliable, https://www.forbes.com/sites/startswithabang/2018/05/22/is-humanity-ignoring-our-first-chance-for-a-mission-to-an-oort-cloud-object/?sh=5d0858e36953
• Speculation cited to 2009, update? Such a mission could be facilitated by Dual-Stage 4-Grid ion thrusters that might cut cruise times considerably if powered, for example, by a fusion reactor.[87]
• Move to FARC, we don't have enough resources to rewrite every Astronomy FA, and no one is keeping up with them. If I found problems in every line by looking at only one small section, two months in to this FAR, we have problems. SandyGeorgia (Talk) 04:36, 11 July 2022 (UTC)[reply]

Calculations in celestial dynamics stay valid, so the 2011 paper didn't go stale or anything. I added a summary of a more recent study. That particular Forbes contributor is an astrophysicist, so it's probably fine. XOR'easter (talk) 05:34, 11 July 2022 (UTC)[reply]

As I look at other sections, it doesn't get better. "The trans-Neptunian planet hypothesis has been advanced in several forms by a number of astronomers, including Rodney Gomes and Patryk Lykawka. One scenario involves perturbations of Sedna's orbit by a hypothetical planetary-sized body in the Hills cloud.". The only mention of the Hills Cloud in the entire article ... what is it? SandyGeorgia (Talk) 04:46, 11 July 2022 (UTC)[reply]

Fixed.

I really don't think the article is in that bad shape. Rushing to demote it just compounds the problem of having too many astronomy articles simultaneously at FAR; I was almost optimistic that we'd get them all finished, but elevating the priority of the least-trafficked of the three articles just makes it harder for the few available volunteers to progress in an orderly way. XOR'easter (talk) 05:59, 11 July 2022 (UTC)[reply]

OK, trust you on this, but concerned that you are being overworked :). So, instead of Move to FARC, I suggest we take more time to make sure this is OK before we let it out of here. SandyGeorgia (Talk) 06:10, 11 July 2022 (UTC)[reply]

Recent scholarly sources to check:

• All the same author?
  • https://link.springer.com/article/10.1134/S1063773721030087
  • https://www.sciencedirect.com/science/article/pii/S0273117721004555
  • https://www.sciencedirect.com/science/article/abs/pii/S0094576521006469
• https://books.google.com/books?id=vaQvEAAAQBAJ&pg=PA374&dq=%2290377+Sedna%22&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwiPq_PFkfD4AhU_q4kEHcO3DBQQuwV6BAgCEAY#v=onepage&q=%2290377%20Sedna%22&f=false If it was thought to be the most distant when discovered, but now there are others known more distant, should we find such basic info in the lead?
• https://books.google.com/books?id=FeU7DwAAQBAJ&pg=PA223&dq=%2290377+Sedna%22&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjH6uvulPD4AhXVkIkEHX7CCOE4HhC7BXoECAsQBw#v=onepage&q=%2290377%20Sedna%22&f=false

SandyGeorgia (Talk) 06:10, 11 July 2022 (UTC)[reply]

• Minor update: I've tried adjusting the image placement to avoid prose getting squeezed between them. It's tricky, with that giant infobox. XOR'easter (talk) 04:26, 4 August 2022 (UTC)[reply]

  I note that over in another discussion, Serendipodous suggested that this be closed. XOR'easter (talk) 19:51, 16 August 2022 (UTC)[reply]

• Could we get an update on status here? What issues remain outstanding? Nikkimaria (talk) 02:22, 24 September 2022 (UTC)[reply]
  • I said that I would !vote to delist on account of this inclusion; it was later trimmed back to something that I could accept, but then expanded back again. So, I have to stick to my guns. The article can have either cruft or the star, not both. XOR'easter (talk) 19:36, 25 September 2022 (UTC)[reply]
    • Based on XOR'easter's comment above, I think move to FARC is the next step here, which doesn't preclude further improvements. Hog Farm _Talk 20:38, 6 October 2022 (UTC)[reply]
    • I have trimmed it back to the version XOR'easter could accept. I do not agree with XOR that this is "cruft" (on the grounds that while it's a personal website, it's the personal website of the person who actually designed the Unicode symbol), but I also think it's too small a thing to bother making a fuss over. Double sharp (talk) 19:13, 10 October 2022 (UTC)[reply]
    • @XOR'easter: Double sharp (talk) 19:36, 10 October 2022 (UTC)[reply]
• Move to FARC, although XOR'easter has made valiant attempts on these planetary articles, they just aren't progressing enough as there is not enough interest and XOR can't do it alone. Similar to what I said at Supernova, it may be time to bite the bullet and deal with the increasing problem in the declining WikiProject which once produced dozens of FAs. They no longer are, and yet we have new FACs being submitted. SandyGeorgia (Talk) 13:21, 7 October 2022 (UTC)[reply]

@SandyGeorgia:: Personally I find it a little insulting that you argue that there's so little interest when I've spent the last 18 months breaking my back trying to get Ceres re-featured and you've cited this very FAR as a reason why it's taking so long. I am prepared to work on this, if and when Ceres is promoted. Serendi^podous 16:37, 14 October 2022 (UTC)[reply]

Issues raised in the review section include sourcing and coverage. Nikkimaria (talk) 03:29, 8 October 2022 (UTC)[reply]

• @Devonian Wombat: You made some significant edits earlier this month. Are you interested in addressing concerns? Z1720 (talk) 18:20, 20 October 2022 (UTC)[reply]

Unfortunately no, I just don't have the time to clean up the massive amount of issues here, even if I could. Devonian Wombat (talk) 21:23, 20 October 2022 (UTC)[reply]

If you want to give me a list, I'd be prepared to fix them. Serendi^podous 13:17, 21 October 2022 (UTC)[reply]

Sandy's left a number of comments above, not all of which seem to have been addressed. For instance, the Forbes contributor piece is still cited in the article. Hog Farm _Talk 13:27, 21 October 2022 (UTC)[reply]

OK, removed. What else? Serendi^podous 16:00, 21 October 2022 (UTC)[reply]

You'll need to go through all of the comments made by Renerpho and Sandy above, see if they've been addressed, and if not, either note why you disagree with them or make the changes in the article. Hog Farm _Talk 13:16, 24 October 2022 (UTC)[reply]

As I said somewhere above, I think that particular Forbes contributor piece was actually OK, but I won't quarrel with its being removed. XOR'easter (talk) 13:27, 24 October 2022 (UTC)[reply]

Serendipodous my apologies for missing the comment above (in the FAR section) while I was on vacation, and your point is taken. Are you still planning to engage here ? If so, where do we stand? SandyGeorgia (Talk) 14:55, 27 October 2022 (UTC)[reply]

HiSandyGeorgia. I have no idea since I cannot tell what's been resolved and what hasn't. Serendi^podous 16:22, 27 October 2022 (UTC)[reply]

OK, I will look back through and highlight anything above unaddressed ... SandyGeorgia (Talk) 17:36, 27 October 2022 (UTC)[reply]

SandyGeorgia: Have you had a look? Serendi^podous 21:18, 14 November 2022 (UTC)[reply]

So sorry ... I have not had time yet ... I mentioned several weeks ago that I had a terribly busy November ahead, and I will catch up as soon as I get a free moment (not sure when that will be, barely keeping up with my watchlist now ... ) SandyGeorgia (Talk) 14:00, 15 November 2022 (UTC)[reply]

Quickly reviewing my comments above from July 11, it appears that XOR'easter addressed all of them but I see no answer on whether the list I included of new scholarly sources has been considered. Please let me know, and then I will do a re-read. SandyGeorgia (Talk) 14:09, 15 November 2022 (UTC)[reply]

I've looked at the links you proivded and they either plan a hypothetical trip to Sedna, or simply mention Sedna without elaboration, Serendi^podous 21:42, 15 November 2022 (UTC)[reply]

Thanks, Serendipodous ... good enough for me. What I meant about undefined AU is that we never define the acronym, and I can't figure out how to add it here because of the convert ...

• orbit; as of 2022 it is 84 astronomical units (1.26×1010 km) from the Sun, ....

That first occurrence of the words astronomical units wants to have an AU after it so we know what AU is later ... I don't know how to fix that. I will try to catch up by this weekend. SandyGeorgia (Talk) 03:02, 16 November 2022 (UTC)[reply]

I hot-rodded it. Serendi^podous 09:36, 16 November 2022 (UTC)[reply]

Please install user:Evad37/duplinks-alt and have a look. There is a problem with dupe links on Astronomical units and sednoids (and others) that I can't fix ... AU is never defined but I don't know how to address this because of the convert, and this results in a dupe link (along with others). SandyGeorgia (Talk) 14:18, 15 November 2022 (UTC)[reply]

AU is linked in the infobox under "Perihelion". I think duplinks in the infobox are ok (certainly the duplinks policy does). I've removed a few that I cought. Can't get that script to load though. Serendi^podous 22:05, 15 November 2022 (UTC)[reply]

SandyGeorgia: Sorry to prod, but you started this FARC, against the advice of more than one person, including yourself at one point. I'm doing what you're asking but I can't do this without you. Serendi^podous 09:53, 21 November 2022 (UTC)[reply]

The FAR was started by Renerpho, not me ... the move to FARC is inconsequential. I will get to this as soon as I have time ... I mentioned long ago that I had a dreadful November ahead ... and this article needs a top-to-bottom read-through, which can't be done quickly. Has anyone pinged Renerpho to see if they are now satisfied ? If others are satisfied, Keep declarations need not wait for me, but I'm not going to lodge a keep until I've read the whole thing ... SandyGeorgia (Talk) 13:54, 21 November 2022 (UTC)[reply]

Keep. Reiterating my earlier !vote. I would be more specific and comment on why the issues that led the article to end up at FARC aren't actually a problem; however, reading the above discussion, I don't understand why the article was moved to FARC to begin with. Sportsfan77777 (talk) 05:26, 15 November 2022 (UTC)[reply]

Neither do I. Serendi^podous 11:05, 15 November 2022 (UTC)[reply]

Starting review on talk. SandyGeorgia (Talk) 14:40, 21 November 2022 (UTC)[reply]

Renerpho this is your nomination; could you please do the followup? I have left a lengthy list on talk; this is not my nomination, the article is not ready for a Keep, and I don't have time to continue engaging. SandyGeorgia (Talk) 19:39, 21 November 2022 (UTC)[reply]

Update: there was a recent requested move, closed, but there remains an underlying dispute about article content. Resolving this matter will require more sustained attention from more FAR participants. See my review on the FAR talk page, linked above. Hog Farm raised this matter in May, and it remains an issue. SandyGeorgia (Talk) 15:50, 22 November 2022 (UTC)[reply]

In addition to FAR talk, there are two threads on article talk. There is no consensus on whether to describe Sedna as a dwarf planet, and the article is not yet stable. SandyGeorgia (Talk) 15:57, 22 November 2022 (UTC)[reply]

Discussion continues on article talk, with no proposal (yet) to resolve the ambiguity in the article. The first line of the lead unambiguously states in Wikivoice that Sedna is a dwarf planet. The Classificiation section makes no such statement, nor is it found anywhere in the article; rather, the Classification section concludes that some astronomers have called it a Dwarf, while it has other classifications from other institutions or bodies.If participants cannot select a methodology for hammering out an agreement on how to come to consensus, the article will remain un-ready to be Kept at FAR. (Meanwhile, I have not heard from Renerpho as to followup on the list I left on FAR talk.) SandyGeorgia (Talk) 15:32, 23 November 2022 (UTC)[reply]

The lead accurately summarized the body. No serious sources were present (or have been offered) that actually dispute the dwarf planet label. The other classifications (Kuiper belt object, etc.) overlap with "dwarf planet" rather than contradicting it. I found this clear enough from the text already, but Double sharp has revised that section to make the point more evident, and I think it's good now. XOR'easter (talk) 17:44, 23 November 2022 (UTC)[reply]

Comment Do we have sources for File:Sednoid apparent magnitudes.png, File:Sednoid orbits.png, and File:EightTNOs.png. The last one has a "newer" (still unsourced) version on Commons with different objects (File:EightTNOS new.png): which one should we use? A455bcd9 (talk) 10:45, 10 December 2022 (UTC)[reply]

I made the first two from JPL orbital parameter data. I helped make [:File:EightTNOs.png] at some point, just taking estimated diameters and scaling images. Each body's pixel diameter could be tested compared to the most recent estimates if any have changed. That's a simple thing to do. Tom Ruen (talk) 14:34, 11 December 2022 (UTC)[reply]

Sorry for the late reply @Tomruen, thanks for the information: problem solved then. a455bcd9 (Antoine) (talk) 09:52, 10 January 2023 (UTC)[reply]

That "newer" version is from 2009, so it's actually much older and heavily outdated. Varuna is unlikely to be a dwarf planet according to current knowledge, and it's not one of the largest known TNOs anymore. Double sharp (talk) 04:36, 12 December 2022 (UTC)[reply]

This FAR has been going for eight months. The nominator was active for four days, and hasn't posted since. It has been nearly a month since anyone raised any objections. Can we close this as Keep now please? Serendi^podous 20:54, 9 January 2023 (UTC)[reply]

• Neutral, leaving this one to the topic experts. SandyGeorgia (Talk) 12:19, 10 January 2023 (UTC)[reply]

• Keep: I performed a cleanup pass through the article, clarifying a few points, refining the lead, making the citations more consistent, adding alt text to the images, and including a "Further reading" section for some recent publications. It seems reasonably up to date and up to snuff, FA-wise. That may change when the 2022 JWST observations of Sedna are reported.[9] Praemonitus (talk) 17:32, 15 January 2023 (UTC)[reply]

I'll try and give this a read-through later this week. Hog Farm _Talk 14:43, 16 January 2023 (UTC)[reply]

@Serendipodous and Praemonitus: - I've left a brief list of comments at Wikipedia talk:Featured article review/90377 Sedna/archive1#HF comments. Hog Farm _Talk 01:00, 17 January 2023 (UTC)[reply]

leaning keep if Praemonitus and Serendipodous are fine with it; I don't feel confident to judge the currency/accuracy of the subject-matter specific stuff. Hog Farm _Talk 02:36, 17 January 2023 (UTC)[reply]

• Keep. All I see is "normal" scientific back and fro. The scientists don't agree themselves, so be it, the article looks fine. Desertarun (talk) 16:46, 28 January 2023 (UTC)[reply]

  That's three keeps and a leaning keep, along with my neutral. It would be helpful at this point if Serendipodous would also enter a declaration (yes, that's allowed :) SandyGeorgia (Talk) 18:38, 1 February 2023 (UTC)[reply]

• Well then, by all means, Keep. Serendi^podous 19:02, 1 February 2023 (UTC)[reply]

• Closing note: This removal candidate has been kept, but there may be a delay in bot processing of the close. Please leave the {{featured article review}} template in place on the talk page until the bot goes through. Nikkimaria (talk) 21:03, 4 February 2023 (UTC)[reply]

The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.