Wikipedia talk:WikiProject Astronomical objects

Hi! I am Lutitium, I am seeking to join a wiki project and as I am interested In Astronomical objects I want to join WikiProject Astronomical objects. But I am a bit confused on how to join and how to make my articles a part of WikiProject Astronomical objects. Also in this project, do you only improve articles or create them as well?

Thanks and bye:D Lutitium (talk) 05:05, 26 October 2025 (UTC)

[]. Or just start editing. Lithopsian (talk) 14:29, 26 October 2025 (UTC)

Hello Lutitium. This project does both: creates new astronomy articles and improves existing pages. It depends on your interests and skills. I'd take a look at the article alerts and the newly created article list on the main project page; that will let you see some of what's happening with this project. Praemonitus (talk) 03:46, 27 October 2025 (UTC)

Ok then how do I join Lutitium (talk) 10:31, 27 October 2025 (UTC)

It's not a club. You just participate, if you want. Praemonitus (talk) 02:49, 23 November 2025 (UTC)

Is there an accepted convention for describing the distance of a satellite from its primary planet? I happened across S/2003 J 9, which states: It belongs to the Carme group, made up of irregular retrograde moons orbiting Jupiter at a distance ranging between 23 and 24 Gm.... Is there an encyclopedic reason to use Gm instead of the (more intuitive to my mind) million km? Thanks! ZenSwashbuckler 21:53, 4 November 2025 (UTC)

No, million km is almost always better, until we get to very large numbers, at which point we should use scientific notation, not the prefixes. - Parejkoj (talk) 19:24, 7 November 2025 (UTC)

Thanks! Is there anything to my concern about Template:Units of length used in Astronomy, then? If so, should I post it on a noticeboard somewhere? ZenSwashbuckler 16:27, 10 November 2025 (UTC)

See Talk:Zeta Puppis#Artists impression to decide whether an image contravenes WP:ASTROART or not. Lithopsian (talk) 19:37, 21 November 2025 (UTC)

Then maybe take a look at Kepler-1625, another one just added as I was typing this (edit: now replaced with an "official" artists impression, not obviously any more realistic, but from a reliable source so not our problem if it is just a random pretty picture). Lithopsian (talk) 19:39, 21 November 2025 (UTC)

The Kepler-1625b illustrations seems fine, certainly does not contradict WP:ASTROART as there is nothing speculative being represented. 21 Andromedae (talk) 18:45, 23 November 2025 (UTC)

At the orbital distance I thought the Subgiant star would appear larger. But that's just nit-picking on my part. Praemonitus (talk) 03:49, 24 November 2025 (UTC)

That's exactly why the guideline was drafted: unless an "unofficial" artist's impression is unambiguously representing known data and nothing else (eg. a plain disc used for size comparisons), it isn't allowed. Nothing to do with whether you think it is speculative or not; it is, by definition, speculative unless it only represents demonstrably WP:RELIABLE facts. If we have to have a discussion about the relative sizes of objects in an image, the colour of an exoplanet, the shape of a star, whether there are star spots or not, then something is clearly speculative. Lithopsian (talk) 12:28, 24 November 2025 (UTC)

One way we could process illustrations from a less reliable source is via WP:OR. I.e. one could tag it with a {{Original research inline}} template and add a '|reason=', although that is intended for text. Alternatively, we might need to create a new inline template for that purpose: {{Original illustration}}. The documentation can then explain how it violates WP:OR and link to WP:ASTROART. Praemonitus (talk) 20:58, 24 November 2025 (UTC)

Well meaning user, but I think we should be strict about this kind of thing. - Parejkoj (talk) 20:21, 22 November 2025 (UTC)

For WikiProjects that participate in rating articles, the banners for talk pages usually say something like:

• "This article has been rated as Low-importance on the importance scale."

There is a proposal to change the default wording on the banners to say "priority" instead of "importance". This could affect the template for your group. Please join the discussion at Wikipedia talk:WikiProject Council#Proposal to update wording on WikiProject banners. Stefen 𝕋ower ^{Huddle • Handiwerk} 19:38, 6 December 2025 (UTC) (on behalf of the WikiProject Council)

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)

(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)

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)

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)

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)

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

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^[a] 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)

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.

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:

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.

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.

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)

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)