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Categorizing Skadi Mons

A few days ago the IAU/USGS announced that Venus's "tallest mountain" Skadi Mons is not a real geological feature. I feel like this article should be kept since there is some coverage about its former status, but I am not sure how to deal with the infobox and categories, which currently treat it as a mountain (when it really isn't). How should disproven geological features be handled? Please leave your suggestions and thoughts on Talk:Skadi Mons. Nrco0e (talk • contribs) 07:50, 20 December 2025 (UTC)

Need help cleaning up Jupiter trojan articles

(Transcluded from main discussion at Wikipedia talk:WikiProject Astronomy#Need help cleaning up Jupiter trojan articles. Please do not reply on this thread, go to the main one linked in red.)

Template:Largest Jupiter trojans and User:Rfassbind/Minor planet articles rewrites JT table are massive lists containing Jupiter trojan articles that were mass-created (or converted from redirects) by the now-inactive user Rfassbind back in 2017-2018. My main issue is that all of these were systematically written with the same copy-pasted writing style, which has odd quirks like italicizing the asteroid's name (like Demophon; other Solar System articles do not italicize names like this), capitalizing the phrase "Gas Giant", and calling Jupiter trojans "Jovian asteroids" (which is also not a standard term). Some of these articles (especially ones on smaller asteroids) may fail astronomical object notability guidelines and thus may need to be redirected, but I can't check all of these individually since there's so many of them. I can't clean all of these alone, so I would really like some help for that. Nrco0e (talk • contribs) 02:38, 21 January 2026 (UTC)

Deadlocked discussion

There is an incipient edit war going on at B-type main-sequence star and a number of related articles. There is a discussion on the subject, now becoming quite long, at Talk:B-type main-sequence star#Luminosity class. It is essentially deadlocked (at 2 to 1, if I might say, myself being one of the 2) and I for one see no hope of changing any of the positions by further discussions of just those three editors. If anyone else feels like wading in, either to arbitrate or to "vote" one way or the other, it would be much appreciated. Lithopsian (talk) 14:54, 4 February 2026 (UTC)

I personally don't think this cannot be solved, there are just a lot of misunderstandings. But of course anybody is more than welcome to participate if interested. Stevinger (talk) 03:12, 5 February 2026 (UTC)

Requested move at Talk:Extrasolar Planets Encyclopaedia

An editor has requested that Extrasolar Planets Encyclopaedia be moved to Encyclopaedia of Exoplanetary Systems, which may be of interest to this WikiProject. You are invited to participate in the move discussion. Slovborg (talk) 19:35, 19 February 2026 (UTC)

Solar & Planetary units templates

I've added a couple more templates for the units featuring astronomical symbols, which I think are useful:

• {{Earth density}} ρ_🜨 – for exoplanets as an alternative to SI units, appears in some sources
• {{Solar density}} ρ_☉ – the same for stars
• {{Solar constant}} S_☉ this one is useful for comparing flux received by exoplanets; however there is no consistency in sources how it's written. S_☉ is the format suggested by the IAU.

In addition I've defined a couple shorthands:

• For Earth, {{rho+}} ρ_🜨 by analogy with previously existing {{M+}} M_🜨 and {{R+}} R_🜨
• For Jupiter, {{MJup}} M_J and {{RJup}} R_J
• For Sun, {{MSun}} M_☉, {{RSun}} R_☉, and {{rhoSun}} ρ_☉
• I'm waiting for approval to use {{So}} (currently an user block template shorthand for spam-only accounts) for the solar constant; by analogy with {{Lo}} L_☉ & in line with a proposal by Mamajek et al. to call this unit "solirad" & write it as So.

The Earth & Solar density don't have working wikilinks defined yet. I'm planning to expand the Astronomical system of units article with the IAU 2015 Resolution B3 which defined the nominal masses & radii, and also suggests how to combine the definitions to get the nominal volume and density. This should serve as a suitable reference to point the link at once it's done.

I expect this can also be incorporated into {{convert}} (this is actually a follow up to my request to support those units there) & {{val}} shortly.

I hope this simplifies some things for other editors as well. If you have any other related ideas please let me know. Slovborg (talk) 20:46, 22 February 2026 (UTC)

Hmm, I'm not sure why object density would be particularly useful or informative for astronomical objects. What does it tell you, really? Most objects have a density gradient, so an average is only relevant at one (unknown) altitude. From my perspective, surface gravity and core density are more relevant and interesting. Praemonitus (talk) 21:08, 22 February 2026 (UTC)

Density seems to be used fairly commonly for exoplanets, crude but about the best that can be done. Is there a nominal earth density defined though? For stars, it is virtually unknown and almost entirely pointless. I'm pretty sure there isn't a nominal solar density, although nominal solar mass and radius are defined units. Solar constant I have no clue. Lithopsian (talk) 21:34, 22 February 2026 (UTC)

I could see density being useful for minor planets, but none of these units would seem applicable. Praemonitus (talk) 00:55, 23 February 2026 (UTC)

I also didn't think there's really a need for Solar density, but then I spotted it being used in the LHS 1903 system discovery paper: , at the top of page 9:

[...] we executed infrared flux method and isochronal analyses to determine the stellar radius (R_★) = 0.539±0.014 Solar radius (R_☉), stellar mass (M_★) = 0.538^+0.039
_−0.030 Solar mass (M_☉), stellar density (р_★) = 3.44±0.35 Solar density (ρ_☉) (4850±490 kilogram per cubic metre (kg m⁻³)), and stellar age (t_★) = 7.08^+2.87
_−1.98 gigayear (Gyr) (19).

Earth density, yes, is commonly used when citing exoplanet values. The values are implicitly defined through nominal masses and radii.

Density gradient can in practice only be measured indirectly, through the Darwin–Radau equation from shape and rotation, through measuring the non-spherical contributions to the gravitational field e.g. Gravity science (Juno), or seismically e.g Seismic Experiment for Interior Structure. All of those require detailed measurements, which we can't always obtain. Even then the interior structure models aren't very well-characterized. How diffuse are Jupiter and Saturn's cores? Hard to tell. But the bulk average value still gives an idea of a body's composition; what's the rock-ice ratio? Does it have an oversized core (like Mercury)? See for example the discussions on bulk composition of Eris, of which we don't have detailed measurements.

Regarding the solar constant, this is really common with exoplanets again, and there are Wikipedia articles that list the values in that unit, e.g. the TRAPPIST-1#Data table, "Radiant flux" column is in fact given in units of S_☉. But it's not available as a column in the {{Orbitbox planet}} template, so it is omitted on most pages, even though it's usually given in system parameter papers. Slovborg (talk) 02:44, 23 February 2026 (UTC)

WikiProject Astrobiology

Hi! Anybody willing to join? We need at least 10 people https://en.wikipedia.org/wiki/Wikipedia_talk:WikiProject_Council#Proposing_a_new_WikiProject_Astrobiology Astropedian

Eclipse notability proposal

We really should have a notability guideline for eclipses. Wikipedia has had a very inconsistent treatment of eclipse notability, particularly those which did not occur recently. I feel that GNG is not a proper criterion to judge the notability of eclipses. Given that eclipses are calculable thousands of years into the past and future, most of them are not notable per WP:NOTDATABASE. However, the most recent eclipses and those observed in the past are generally held to be notable. How, then, do we decide which eclipses should have articles? I propose creating a new notability guideline for eclipses, possibly hosted at WP:NECLIPSE or something similar, including a definite date where all eclipses, regardless of coverage or type, are certain to have articles, and only notable eclipses outside of those dates get an article.

Pinging active WikiProject Eclipses participants: @Hurricane Clyde @HurricaneEdgar @Cullen328 @Vestrian24Bio; currently active participants in past eclipse AfD discussions: @Rsjaffe @TH1980 @TheTechnician27 @Praemonitus @LaundryPizza03 @InterstellarGamer12321 @Athel cb and other relevant users: @AstroLynx 🪐Kepler-1229b | talk | contribs🪐 05:26, 31 March 2026 (UTC)

@Kepler-1229b, I think your idea is great but there is one mistake, there should be some minimal coverage, having no coverage means it's simply non-notable. Like the article should contain more that one citation and both of them should at best comes from two different separate sources. Also the rule potential should have more priority. Abdullah1099 (talk) 10:41, 31 March 2026 (UTC)

@Abdullah1099, @Randy Kryn, my opinion is somewhat different. In terms of past eclipses, having no sources other than that eclipse guy over at NASA could be a sign of non-notability. However, I don't necessarily believe that the same rule should apply to future eclipses, especially those that are still more than 20 years out for partial eclipses, or more than 50 years out for total, annular, or hybrid eclipses. Hurricane Clyde 🌀^{my talk page!} 13:25, 31 March 2026 (UTC)

@Hurricane Clyde, I meant that atleast some minimal sources should be present in Eclipse article, it doesn't matters it's future or past. Yeah, Eclipse in 20-25 years in future may be notable but similar can't be told about Eclipse in 50-60 years in future in or so that can also make the article WP:TOOSOON Abdullah1099 (talk) 13:40, 31 March 2026 (UTC)

Why not make events part of WP:NASTRO? –LaundryPizza03 (dc̄) 14:55, 1 April 2026 (UTC)

@LaundryPizza03 We would have to rename the guideline in that case. I prefer a standalone guideline for eclipses, but am not opposed to adding both in the same page. 🪐Kepler-1229b | talk | contribs🪐 19:31, 1 April 2026 (UTC)

I think this discussion is a very good idea and I agree that we should consider standardising eclipse notability guidelines. For past eclipses, I think any eclipse with recorded observations should be kept, whereas those with no records can be redirected to the most relevant lists with possible mergers to prevent the loss of any extra information, although eclipses that were otherwise superlative or interesting in some way should be kept. For future eclipses, I am less sure: we could create a time boundary (e.g. 2100) to decide which eclipses are kept and redirected in order to align with WP:TOOSOON but this would be arbitrary. Even if we did create this time boundary, superlative eclipses after the boundary would still be notable and worth keeping, so this would not be a complete solution. InterstellarGamer12321 (talk | contribs) 14:27, 31 March 2026 (UTC)

🪐Kepler-1229b | talk | contribs🪐 05:26, 31 March 2026 (UTC)

• Keep as many as possible and maybe stop the AfD chain. Each eclipse is notable, and past editors have taken the time to write up articles on each of these historical events. Note that Wikipedia notability does not diminish over time. Thanks. Randy Kryn (talk) 10:49, 31 March 2026 (UTC)

  @Randy Kryn Most of the articles at AfD for Wikipedia:Articles for deletion/Solar eclipse of March 14, 1801 were created by a sock account and were certainly not observed by anyone, and so are not notable under my criteria below. However, I agree that many of these articles should be restored. The rest are certainly notable under my proposed criteria. We should definitely not AfD more articles until consensus is reached here. 🪐Kepler-1229b | talk | contribs🪐 15:32, 31 March 2026 (UTC)

• Why don't you try putting together a draft criteria so we can discuss it? The notability of an eclipse may depend on the type, visibility, path location, and whether there were published national expeditions. Some criteria can be used to assume an eclipse is notable; others can be ruled out unless it satisfies the WP:GNG. Also, I don't agree that every eclipse is notable: historical lunar eclipses are rarely notable, for example. Praemonitus (talk) 14:38, 31 March 2026 (UTC)

  @Praemonitus I propose the following: Any eclipse which has had any historical significance before 1900, or was the subject of scientific papers and other literature ofn the matter, gets an article. Eclipses from 1900 to 2100 also get an article, regardless of any observations, etc. All other eclipses past this date must have some kind of scientific interest to get an article; for example, we can make an exception for the July 2186 solar eclipse due to its exceptionally long duration (7 minutes 29 seconds).

  Also, to address your last point there, what makes you think that? Plenty of historical lunar eclipses have had much significance according to the criteria I listed above; the type of eclipse should not be a basis for determining notability outside of the definite dates. Only observations or historical significance, in my opinion, should be a factor in eclipse notability. 🪐Kepler-1229b | talk | contribs🪐 15:25, 31 March 2026 (UTC)

  • An automatic criteria needs to be conservative, so additional criteria are needed beyong just a starting date. At the very least, a partial lunar or solar eclipse should be non-notable unless shown by weight of sources. A total solar eclipse path that does not cross near a population center should be considered non-notable, unless there was an expedition or scientific papers. Praemonitus (talk) 15:41, 31 March 2026 (UTC)

    @Praemonitus Wikipedia should be consistent in its coverage of eclipses. I do not care too much for the precise date, which may be adjusted as necessary, but the type of eclipse is not relevant unless it was, say, an invisible penumbral lunar eclipse that occurred in 1951 or so. I think your guidelines could be applied outside of the date guideline, although partial lunar eclipses, for example, have proven historically notable otherwise as they are quite noticeable in the sky. Any and all eclipses, no matter how invisible, occurring in recent times, and somewhat so even further back, can easily be shown to meet GNG aside from eclipse-specific guidelines. 🪐Kepler-1229b | talk | contribs🪐 15:51, 31 March 2026 (UTC)

    • I disagee. Wikipedia treats articles individually, rather than as groups. Wikipedia-style notability should not be bestowed based on some consistency criteria. If GNG is easy to demonstrate, then we don't need a notability guideline. Praemonitus (talk) 16:02, 31 March 2026 (UTC)

      @Praemonitus Even if our proposed eclipse guidelines do not apply, any eclipse, and I do mean any, that took place in recent times still has sufficient coverage to meet GNG. Take, for example, August 2016 lunar eclipse. Even though the eclipse may not even have occurred, there was still coverage of the "eclipse" by The Weather Network. In these instances, it would be useful to impose a date range for all eclipses in these dates to be notable and have articles. 🪐Kepler-1229b | talk | contribs🪐 16:15, 31 March 2026 (UTC)

      • I'm unclear that such data would be sufficient, but I'm not interested in a lengthy debate. Good luck. Praemonitus (talk) 17:34, 31 March 2026 (UTC)

  I think this rule can be useful Abdullah1099 (talk) 15:32, 31 March 2026 (UTC)

  @Abdullah1099 What timepoint do you propose to establish to delineate notability for eclipses? 🪐Kepler-1229b | talk | contribs🪐 15:33, 31 March 2026 (UTC)

  Sorry @Kepler-1229b but as of now i don't have that much knowledge regarding eclipses, I first had to observe the article to determine any timepoint. But i think 1990 is fairly good timepoint. Abdullah1099 (talk) 15:36, 31 March 2026 (UTC)

  @Abdullah1099 Personally I think 1990 is very late for including eclipses; from what I can see on the Eclipse Wikiproject page; eclipses between 1900 and 2100 all should have articles. 🪐Kepler-1229b | talk | contribs🪐 15:39, 31 March 2026 (UTC)

  Yeah, that is also possible. But i think there should be a reson like used in WP:NASTRO. Abdullah1099 (talk) 15:41, 31 March 2026 (UTC)

  @Abdullah1099 See my above comments. 🪐Kepler-1229b | talk | contribs🪐 16:17, 31 March 2026 (UTC)

  Bro i read it but i mean is there any reason similar to criteria 4 of WP:NASTRO which states "The object was discovered before 1850, prior to the use of astrophotography or automated technology". Abdullah1099 (talk) 17:01, 31 March 2026 (UTC)

  @Abdullah1099 The closest thing I can think to this would be either a set date for notability or an eclipse observed prior to the set dates, both of which are included in my proposal. 🪐Kepler-1229b | talk | contribs🪐 17:02, 31 March 2026 (UTC)

  Ok thats good thing Abdullah1099 (talk) 17:05, 31 March 2026 (UTC)

• I find eclipses fascinating, but in Wikipedia terms, there is nothing unique about eclipses as opposed to any other topic area. When it comes to freestanding articles, we should have an article about any eclipse that has been the subject of significant, in-depth prose coverage in multiple, reliable sources. Other eclipses that are simply covered in routine astronomical databases or have minimal coverage can be covered on Wikipedia in list articles. Cullen328 (talk) 16:46, 31 March 2026 (UTC)
• So for those unaware, this RFC result from '22 is what got us to "eclipses must meet GNG". To reply to Randy's comment that Each eclipse is notable, well... no, they aren't. If the only references for an eclipse are tables of calculations or values, then it doesn't meet GNG. I'm not sure why we need an SNG for eclipses when the general case works fairly well (most of the time). Primefac (talk) 22:33, 1 April 2026 (UTC)

New version of File:Asteroid proper elements i vs e.png

What a difference 20 years can make! I've just updated File:Asteroid proper elements i vs e.png. This is a chart of some of the structure of the main asteroid belt. It especially shows the numerous asteroid families, visible as "clumps". The improvements are mainly due to a roughly 12-fold increase in data. More accurate computation of synthetic orbital elements also plays a role, resulting in less scatter overall. Some families that were barely visible in the old plot are now very obvious.

Proper orbital elements (inclination i_p vs. eccentricity e_p ) for multi-opposition asteroids in the main belt

• 
  As of March 2005 (about 96,000 asteroids)
• 
  As of April 2026 (about 1.15 million asteroids)

I've also re-uploaded the old chart, mainly because it has been around for so long and there may be an interest in keeping it (for "archival purposes"). It can be found at File:Asteroid proper elements i vs e (old version).png.

In addition to the chart for the full asteroid belt, I have uploaded charts for the different regions of the asteroid belt. There are now so many objects/structures that it makes sense to split the diagram into four parts, corresponding to the inner (A), middle (B+C), and outer (D, E+F+G) asteroid belt, with the classification as in File:AsteroidIncAu.png:

• 
  A-belt (a<2.5 AU)
• 
  B- and C-belts (2.5<a<2.82 AU)
• 
  D-belt (2.82<a<2.95 AU)
• 
  E-, F- and G-belts (a>2.95 AU)

Renerpho (talk) 10:01, 15 April 2026 (UTC)

Looks good (and informative)! Are there going to be annotated versions for different families? Praemonitus (talk) 13:45, 15 April 2026 (UTC)

@Praemonitus: That depends on what is needed. I can't make a plot for every single family (there are hundreds of them), and a single plot that names all of them would be impossible to read (again because there are so many). I definitely could make annotated versions for individual families as needed.

I can also customize the plots, as in the example below, where I scale objects by size. This is zooming in on the asteroid family around 293 Brasilia. Two smaller families are also visible as clumps, but are not annotated.

• 
  D-belt, zoomed in and annotated
• 
  i vs. a
• 
  e vs. a

I have also made plots for inclination vs. semi-major axis and eccentricity vs. semi-major axis. Compare the version of the "i vs. a" plot from 2005 that is currently used on Wikipedia, as in File:Juno_clump.png. I could make replacements for those as well, using the new charts, at least where a clump/family has its own Wikipedia article that could use it (as is the case with Juno clump). I would also suggest that I use the sub-charts for this (i.e., the chart for the B&C belt for the Juno clump). Renerpho (talk) 06:11, 16 April 2026 (UTC)

Nice. We do have a 9-member "Asteroid family#Prominent families" section that could make a useful target list, if you want. Thank you. Praemonitus (talk) 14:35, 16 April 2026 (UTC)

@Praemonitus: Sounds good! I'll have a look at those, and see what I can do.

I've also added an annotated version of the main plot. While it is certainly crowded, and I don't know how to avoid that, it's still somewhat useful to give an idea of what is what. I'm still wondering about better ways to do that. Also note that my annotations just cover the ~330 families identified by Nesvorny in 2025. These are not all known asteroid families (and some obvious ones in the plot are lacking an annotation). We have a list of Asteroid family#All families, based on Nesvorny (2015), by which time he and his colleagues had identified 122 families in the main belt. While that number has tripled in the decade that has passed since, I am not prepared to update that list.

• 
  An annotated version of the main plot
• 
  Just the D-belt (2.82<a<2.95 AU), with objects scaled by size

One way to annotate these would be to add annotations just to the sub-plots, like I did there for the D-belt. Even that is running into problems where families lie close together, or are nested within each other. Renerpho (talk) 15:05, 16 April 2026 (UTC)

Some of the examples I find on the internet use color coding for different families. Praemonitus (talk) 01:44, 17 April 2026 (UTC)

Craters on the Moon templates

We have the following templates:

• {{Craters on the Moon: A–B}}
• {{Craters on the Moon: C–F}}

but there are no equivalent templates for the other ranges under Category:Lists of impact craters on the Moon. I.e. G–K, L–N, O–Q, R–S, and T–Z. Should we extend them or WP:TfD them? If the former, then I suggest they be interconnected, perhaps with links at the bottom. Praemonitus (talk) 22:15, 4 May 2026 (UTC)

I think it would make more sense to delete them than to expand the range. Generally speaking someone looking at a navbox will want to move between related items. In the case of something like {{Star systems within 10 light-years}} that relationship is "close stars", but I can't see any reason why someone would have a preference to navigate from C. Herschel (crater) to C. Mayer (crater) when they're probably more interested in going to Heis (crater) (which is next to Herschel). Primefac (talk) 10:11, 6 May 2026 (UTC)

Yes that makes sense. It would probably be better to have templates based on the List of quadrangles on the Moon, but I'm not sure how much need there is for that. Praemonitus (talk) 14:18, 6 May 2026 (UTC)

Unless there's an objection, I think what I'll do is replace them with a {{The Moon}} template (since that has a link to the crater list). Once the two CotM templates are all removed, I'll take them to TfD. Praemonitus (talk) 14:03, 7 May 2026 (UTC)

The easier (and less bureaucratic) option would be (again, assuming no objection) simply redirecting the two templates to {{The Moon}}; not only will it save you ~500 edits but it's not exactly an illogical redirect target (as an {{R from more specific name}} or similar). Primefac (talk) 11:36, 8 May 2026 (UTC)

• Should Keep the navboxes, as long as they exist there's nothing seriously wrong with them. Thanks. Randy Kryn (talk) 12:44, 8 May 2026 (UTC)

  Just because they exist and there isn't anything "wrong" with them does not mean they are useful. Primefac (talk) 13:28, 8 May 2026 (UTC)

  How are they not useful? The only other way of finding a list of craters is in a category, and navboxes and categories are complementary to each other. Would be nice to have the further navboxes but since these two exist keeping them does no harm to Wikipedia. Randy Kryn (talk) 13:46, 8 May 2026 (UTC)

  See my argument a few lines above for why they don't actually provide useful navigation. That is just my opinion of course. Primefac (talk) 13:55, 8 May 2026 (UTC)

  From the Moon navbox, click on the "List" link next to craters. That will provide you with a full set of links to the lunar craters. Right now the navboxes only link to a smaller range, and only for a subset of lunar craters. That's hardly useful, and would be redundant with the Moon navbox. Praemonitus (talk) 14:23, 8 May 2026 (UTC)

  The list and category are fine, but so are the navboxes. See Wikipedia:Categories, lists, and navigation templates and its summary. These three forms of navigation complement each other. Just saying that as long as the two navboxes exist they should continue to exist, and hoping that's not too controversial. Thanks. Randy Kryn (talk) 15:03, 8 May 2026 (UTC)

  Per WP:TFD#REASONS, NavBoxes can be removed when it is redundant with a better designed template. Right now, with the list link, the '{{The Moon}}' template covers all of the lunar crater space, whereas these two do not. They don't even interlink with each other, so it's a substandard design. But what we might consider is adding the lunar crater sublistings to The Moon template for faster access. Praemonitus (talk) 16:17, 8 May 2026 (UTC)

WikiProject Astronomical objects/Catalogues sub page

What should we do with Wikipedia:WikiProject Astronomical objects/Catalogues? Right now, the only place on all of Wikipedia that links to this is the discussion at Wikipedia talk:WikiProject Astronomical objects/Archive 27#Wikipedia:WikiProject Astronomical objects/Catalogues, from June 2018. Most of the maintenance pages listed on it have not been edited since 2018. I feel like these sub pages are either useless, or are an asset that's underutilized.

I'm tagging User:Headbomb, since it's their work: Maybe you have an idea what this is for, and what should happen to it. Are you using this; and if so, for what? I'm also tagging User:GurrenLagannTSS, who made me aware of this and may have input of their own. Renerpho (talk) 22:59, 17 May 2026 (UTC)

"an idea what this is for" exactly what it looks like. An at-a-glance page that gives the status of how these catalogues are represented on Wikipedia. Works especially well with User:Anomie/linkclassifier. Headbomb {t · c · p · b} 23:16, 17 May 2026 (UTC)

It looks like an abandoned project to me. There's no link to that page anywhere, making it quite obscure. Surely there's a better way to utilize this by making it more visible? Renerpho (talk) 23:20, 17 May 2026 (UTC)

Feel free to correct me on this @Headbomb, but it seems like these were made as an effort to ensure every entry in these WP:NASTRO-compliant catalogues have a article or redirect?

I personally believe that some of these lists (mainly Messier, HR and Abell) are very useful for maintenance purporses and they should be linked somewhere in this project or in WP:NASTRO itself. However, given that WP:NASTRO states that not every object in the NGC catalogue is notable by itself, is the NGC page really needed? Its not covered by WP:NASTRO, hence kinda defeating the purporses of that page. On the opposite end however, the HR/Bright Star Catalogue page is extremely useful given that we still have hundreds of bright stars that meet WP:NASTRO and still don't have Wikipedia articles!

If i had to make a change to the lists though, it would be nice to add an additional purporse to track the quality of said articles, in order to make it a project to have articles for then that actually have, say, at least a quality code of B or A (to the extent of the sources on then). GurrenLagannTSS (talk) 00:04, 18 May 2026 (UTC)

It's a quick way to see what currently exists and what's missing. Some catalogues are more complete than others. For e.g. Herschell, the issue mostly seems to be that redirects haven't been created. This list could be used to (semi)automate the process though I don't know if this is an official numbering, giving they should be a subset of Herschell's 2500. Headbomb {t · c · p · b} 01:46, 18 May 2026 (UTC)

At the very least we should link it from somewhere more prominent; it doesn't do much good as a reference/maintenance/update page if no one can (easily) find it. Primefac (talk) 21:04, 18 May 2026 (UTC)

Problems with Asteroid family

I had planned to work on the Asteroid family article (compare the discussion above). That article is outdated by more than a decade. However, I currently cannot do so. The problem is how Wikipedia uses the concept of FIN numbers. We treat them as fixed numbers associated with an asteroid family, and use them as such in the lede sections of lots of articles, and not in a very consistent way. Examples include Nysa family ("The Nysa family (adj. Nysian; FIN: 405) is ..."), Eos family ("The Eos family (adj. Eoan /iːˈoʊən/; FIN: 606) is ..."), and basically every other article about an individual asteroid family. More annoyingly though, every one of the nearly 1,000 sub-lists of List of minor planets contains countless entries that all link to a table in the Asteroid family article that uses the old FIN numbers (in the wiki-links in the third-to-last column, as here -- like so: DOR), and those links will be broken by the update.

FIN numbers were introduced by Nesvorný et al. (2014), the paper that is currently used in the Wikipedia article, as a short and unique identifier. However, the FIN numbers have since been redefined by those authors, when it became clear that 3 digits won't suffice. In the redefined version, the Nysa family has FIN number 1005, while the Eos family has 3006. In chapter 2.1 ("Family Identification Number") of Nesvorný et al. (2026), one of the three papers (Nesvorný et al. 2024, 2025, and 2026) on which I plan to build the Asteroid family article, they explain the concept and the changes. That paper comes with a license suitable for Wikipedia, and I think I will use the very nice figure 1 in the Asteroid family article.

All wiki-links to the old FIN numbers will be broken once the article is updated, and I need help or else I'll leave behind a mess. I think I can sort out the articles for individual families manually, but the List of minor planets looks like a job for a bot. At the same time, that bot should change all the entries in the table to agree with the membership status given here. Our lists are currently based on a 12-year old publication, and many asteroids have since had their family status changed. At the same time, the number of identified asteroid families has increased from 122 in 2015 to more than 330 in 2026, while the number of asteroids that are assigned to a family has risen from about 100,000 to more than 400,000. I'd also need help with the ~500 articles about individual asteroids that link to FIN tbl; see .

Full disclosure, I am responsible for suggesting the names of one of those new families, with the primary body (217472) 2005 WV105 a.k.a. 217472 Addams, and of two of its members (379470 Carolynjones and 636680 Lisaloring), to the IAU. Those were published in WGSBN Bull. 6, #8 (25 May 2026). I don't think the resulting conflict of interest will influence the edits I plan to make, although this is why I became interested in working on the Asteroid family article in the first place. Nesvorný is mentioned in the naming citations. I plan to treat FIN 3056 like any other family; if the Addams Family pun is considered to be worth mentioning here or elsewhere, that will have to be by a different user.

I am tagging Tom.Reding, who is most active in maintaining the lists of minor planets. Maybe you can help? Renerpho (talk) 08:42, 27 May 2026 (UTC)

I've been migrating away from FINs when possible in the LoMPs, substituting a direct link to the family article instead, if one exists. However, there are many families without articles, so the FIN table serves an important roll as a catch-all link of last resort. Updating FINs is fine, if done carefully & methodically. Before any such edits are made, you should create a before-and-after table of FINs, preferably at Talk:Asteroid family, for editors to inspect. One column for the 'original' FINs in the current FIN table & another column with the new FINs. I can help with the update once that's done & after a discussion period to catch any potential issues. Preferably, this update will be done in between major MPC updates (we are due for one soon, and the MPC has been in preparation mode for a while), to avoid confusion & to keep the edits in a clean window with no other significant edits taking place.

For family membership, I use AstDyS-2's Parent Body field, which avoids FINs altogether. If the Parent Body has an asteroid family associated with it, I link to that asteroid family article; otherwise, I link the Parent Body to its place in the FIN table, which I have stored offline, since the table has been stable until now.   ~ Tom.Reding (talk ⋅dgaf)  12:11, 27 May 2026 (UTC)

@Tom.Reding: I have replied over at Talk:Asteroid family#Discussion at WikiProject Astronomical objects with the before-and-after FIN table you asked for. Renerpho (talk) 14:25, 27 May 2026 (UTC)

Which provisional designations should we use for asteroids?

The planet infobox does not have a param for provisional designation, but these are commonly entered under "alt names". Do we want all of them, or just important ones? E.g. for Ceres, the multiple provisional designations are trivia. I doubt anyone looking up Ceres on WP rather than at the MPC is going to care about them.

But for more recently discovered named asteroids, it's not clear which provisional designations should be listed. The two obvious choices, IMO, would be the one published with the MP number, and the one with the oldest date. I don't know the background of why the MPC doesn't pick the oldest discovery to associate with the MP number, unless this is just a matter of the connection not being discovered until after the number is assigned.

Also, the discovery date we give is generally the year of the provisional designation that we list, even though the body was often first discovered years earlier. For that reason alone, I think that we should list the oldest provisional designation, and maybe correct the discovery date accordingly. But I could also see an argument for listing the provisional designation that was published with the MP number, as it's probably more common in publication.

The multiple other provisional designations sometimes assigned seem to me to just be trivia, but maybe they're sometimes important for x-ref. If so, where do we draw the line? I'm not sure it would be a good idea to clutter up Ceres's info box with all those later provisional designations, but it would be inconvenient if someone tried looking up an asteroid by its provisional designation and couldn't find it because that's one that we decided not to list.

So, should we choose one provisional designation consistently, list both the oldest and first published provisional designations, or all of them? — kwami (talk) 21:35, 1 June 2026 (UTC)

My thought would be to only include those designations that are useful for searches or are used in published catalogues, but always include the discovery provisional designation, if available. Praemonitus (talk) 13:48, 2 June 2026 (UTC)

Catalogues rather than just MPC announcements is probably a good idea, but not sure what counts as the discovery. — kwami (talk) 14:14, 2 June 2026 (UTC)

The MPC distinguishes between primary provisional designations, and all others. The easiest way to find those is to look up the object in the JPL database , and then look under "Alternative designations". The primary one is shown in bold (it is also used in the name at the top of the page).

I would always give the primary one, and only include others if they are relevant and/or if they are used in the literature (beyond the MPC's or JPL's databases). For example, asteroid 29075 has the primary designation 1950 DA, but an alternative designation 2000 YK₆₆ that is used in some publications and which is relevant for the object. If that asteroid ever gets named, I think both 1950 DA and 2000 YK₆₆ should go in the "alternative designations" field.

On the other hand, articles like 4337 Arecibo, currently listed as a Good Article, gives all four provisional designations for that asteroid, even though there is zero use in the literature for any of them... Renerpho (talk) 15:30, 2 June 2026 (UTC)

Okay, it looks like I don't understand how this works. In the case of 4337 Arecibo, is 1933 HE a PD assigned in 1933 for an object that would only later be identified as (4337), or was it discovered in 1985 in plates photographed in 1933 but not noticed at the time? I had always thought that the date was the date of reporting to the MPC.

If either is standard practice, that is info that should be added to our article on MP naming. If both occur, or if the convention has changed over the years, then that's also something that we should note.

Even if 1933 HE is a precovery image, there are cases where a modern discovery that got some attention under its PD is later identified as being the same object as an earlier PD. In such cases I would think both would be relevant.

In the documentation for the infobox we should state which PD's to use. — kwami (talk) 23:06, 2 June 2026 (UTC)

If we can get a consensus, some appropriate wording could be added to WP:ASTROSTYLE. Praemonitus (talk) 02:01, 3 June 2026 (UTC)

JPL uses two PD's for "517103 (2013 EM20 = 2008 AO112)". — kwami (talk) 04:40, 3 June 2026 (UTC)

2013 EM₂₀ is the primary provisional designation, assigned at the time when the object was numbered. Before numbering, all provisional designations are handled equally. For an example, see 2010 HK₂₂, which has two alternative designations listed (2025 XU and 2010 HE₁₁₁), but there's no primary provisional designation, because the object has not been numbered yet.

I had always thought that the date was the date of reporting to the MPC. -- The provisional designation is assigned based on when the observation was made. Whether the image was found in 1933 or 1985 or 2030 doesn't matter, it will always be "1933 H...". In the case of 4337 Arecibo, all four provisional designations were known when it was numbered in 1990, and the primary provisional designation for 4337 Arecibo was decided to be 1985 GB, assigned at that time based on who received discovery credit. Compare M.P.C. 15690 (page 90), quote: "(4337)* 1985 GB = 1933 HE = 1979 FR3 = 1979 HG2": and M.P.C. 16445 (page 155), quote: "(4337) Arecibo = 1985 GB Discovered 1985 Apr. 14 by E. Bowell at the Anderson Mesa Station of the Lowell Observatory." Renerpho (talk) 07:56, 3 June 2026 (UTC)

So when an unnumbered object has multiple PD's, we normally use the one the MPC does, but that's not primary in any way? The fact that the MPC chose 2010 HK22 doesn't promote it? I thought perhaps one wasn't bold because its use as the page name was enough to clarify.

Okay, the 4 PD's were known to be the same object when Arecibo was numbered, but presumably they weren't when they were assigned. So do we know why they were assigned? If it was from people looking for precovery images, why were new PD's created? Or is it that they reported that they'd found objects in their search, but hadn't yet confirmed that they were the object they were looking for? — kwami (talk) 08:32, 3 June 2026 (UTC)

@Kwamikagami: What precovery images? 1933 HE was assigned in 1933, to a one-nighter seen at Heidelberg (observation published in , Nr. 15, 1933). 1979 FR3 and 1979 HG2 were both assigned on 13 October 1981 -- the first to a single observation from March 1979, the second to a pair of observations from April 1979. Both were assigned and published on the same day in (pages 48 and 49-50, respectively), without being recognized as the same object. 1985 GB was assigned to a single-nighter in 1985 (, page 71). This time, the object wasn't quickly lost, but was observed again a few days later. There would have been a fifth designation in 1969, but an observer error led to it being falsely reported as a recovery of comet 56P/Slaughter-Burnham (, ). Those observations (especially the one made on 8 September 1969) were never reported to the Minor Planet Center, so no provisional designation was assigned at the time. When it was realized that this was asteroid 4337 Arecibo, assigning a new provisional designation was no longer necessary because the asteroid had already been numbered. Renerpho (talk) 10:55, 3 June 2026 (UTC)

Okay, so I take it PD's are not assigned to precovery images then.

I would assume that, in order for the orbit to be sufficiently secure to assign the number, at the time at least some of those observiations had to have been recognized as being the of same object.

Do you have the circular that shows which PD's were identified when the number was given? (I still haven't figured out how to look that up.) — kwami (talk) 20:50, 3 June 2026 (UTC)

we normally use the one the MPC does -- The MPC gives "2010 HK22 = 2010 HE111 = 2025 XU". They simply sort chronologically, which I guess promotes 2010 HK₂₂, as it is undoubtedly the earliest one, but it doesn't make that designation "primary". Being the earliest observation doesn't mean that this is going to become the primary designation once it is numbered. For example, (307371) 2002 RU₂₈₉ was listed as "2000 CF109 = 2002 RU289 = 2010 LJ30" prior to being numbered. The primary designation is 2002 RU₂₈₉. A similar example is asteroid 720373. Renerpho (talk) 11:17, 3 June 2026 (UTC)

So, "primary" is defined by JPL, not by the MPC? Do other nations accept JPL as the authority for MP designations?

The link does not show that (307371) was listed as "2000 CF109 = 2002 RU289 = 2010 LJ30" prior to being numbered, as that page was created for the number. That might be relevant to deciding which PD is primary, if for example they chose the earliest known at the time the number was assigned, and identified other (earlier) PD's later. — kwami (talk) 20:37, 3 June 2026 (UTC)

They are defined by the MPC. JPL's website is simply the most convenient place to look them up, imo. Of course the MPC Explorer works, too. However, the primary provisional designation is not defined until the object gets numbered, so what the MPC Explorer lists as the primary designation will only be meaningful for numbered objects. Renerpho (talk) 21:59, 3 June 2026 (UTC)

MPC Explorer lists a primary provisional designation for both numbered and unnumbered objects. SevenSpheres (talk) 20:59, 3 June 2026 (UTC)

Thanks! — kwami (talk) 21:04, 3 June 2026 (UTC)

I suppose it is simply the chronologically earliest one for unnumbered objects. Renerpho (talk) 21:51, 3 June 2026 (UTC)

So why is it not the earliest for numbered objects? Was it perhaps the earliest when the number was assigned, only for additional PD's to be recognized later? — kwami (talk) 22:20, 3 June 2026 (UTC)

That may also relate to who gets credit for the discovery of an object, if it's not the first person to observe it. — kwami (talk) 23:32, 3 June 2026 (UTC)

@Kwamikagami: I'm not sure how those are selected. In the case of (307371) 2002 RU₂₈₉, all three designations were known at the time of numbering. See the identification published in , p. 360 (18 February 2011). When it was numbered in December 2011, the primary designation was chosen to be 2002 RU₂₈₉ (, p. 293), even though the discovery observation is that of 5 February 2000, corresponding to the designation 2000 CF₁₀₉ (published in , p. 541, on 18 April 2000).

The 2000 CF₁₀₉ tracklet was made by station 703 (Catalina Sky Survey), while the 2002 RU₂₈₉ tracklet is by station 644 (Palomar Mountain/NEAT). Discovery credit went to Catalina Sky Survey. Renerpho (talk) 23:39, 3 June 2026 (UTC)

The process could involve things that are not easily recognizable from the published records -- for example, which tracklet was first used to compute a meaningful orbit, or the order in which the identifications were made internally. Renerpho (talk) 23:42, 3 June 2026 (UTC)

It looks like 2002 RU₂₈₉ may have been the primary PD even before numbering, as the object is only listed under that PD -- there's no cross-ref under 2000 CF₁₀₉ or 2010 LJ₃₀. Who knows, perhaps credit goes to whoever recognized them as the same object. (I suppose that would go with whoever computed a meaningful orbit.)

But it's good to see that the primary PD does not always correspond to the listed discovery date.

At least on WP, I've seen discovery dates later than the earliest PD. Perhaps in such cases those are PD's that had not been identified when the number was assigned, with its accompanying discovery date, so that the discovery date we list is no longer valid? If that's been happening, then IMO we should list the earliest PD in addition to the primary one. (If our discovery date matches the earliest PD, then maybe that wouldn't be necessary.) — kwami (talk) 00:02, 4 June 2026 (UTC)

Yes, I think listing the designation that corresponds to the discovery observation is a good idea. Renerpho (talk) 00:12, 4 June 2026 (UTC)

"... so that the discovery date we list is no longer valid" -- The discovery date remains valid, unless the MPC reassigns the discovery to someone else. That happens sometimes, but rarely.

Not every PD qualifies as a discovery; it has to meet certain criteria. For "modern" discoveries, those made after 2010, those are defined in the infamous MPEC 2010-U20. For example, it must not correspond to a single-night arc at that opposition, and the data must have been submitted to the MPC before any other observation that may qualify as a discovery. The latter is not something that can be checked without access to the MPC's internal database. Renerpho (talk) 00:18, 4 June 2026 (UTC)

In that case, I'm not sure there's much practical difference between an early observation that got a secondary PD and a precovery that didn't. Still, if a PD precedes the primary PD, we might want to list it as an alt. — kwami (talk) 02:11, 4 June 2026 (UTC)

You might want to check out 152830 Dinkinesh. I wrote up its history of provisional designations back when it was unnamed. It was primarily known by its first provisional designation 1999 VD₅₇ at the time. Nrco0e (talk • contribs) 06:56, 4 June 2026 (UTC)