Talk:Planet

The IAU definition of "planet" has too much weight
The article's use of the IAU definition of "planet" has too much weight; the entire article is structured around it. As has been said at this link, the IAU's definition is not the "final word". The geophysical definition of "planet" (in which moons such as Ganymede are considered planets) should be given more weight. Possibly a major rewrite of the article should be done by someone to address this problem. For example, the first paragraphs of the article are very IAU-centric and should include a non-IAU perpsective. LumaP15 (talk) 01:04, 3 September 2018 (UTC)
 * Again, the IUGS would have to approve it before it could be added here.  Serendi pod ous  07:33, 3 September 2018 (UTC)
 * New to this discussion here. Why would the IUGS be the final authority? Grinspoon and Stern https://www.washingtonpost.com/news/speaking-of-science/wp/2018/05/07/yes-pluto-is-a-planet/?utm_term=.1bde2f497aa0 and other scientists https://phys.org/news/2017-02-geophysical-planet-definition.html argue that different definitions should be acceptable depending on context. The topic is described as controversial in the community (example in Phys.org) and books are written that emphasize that dwarf planets are also planets https://www.scholastic.com/teachers/books/13-planets-by-david-a-aguilar/. Highlighting the proposed "geophysical definition" https://www.hou.usra.edu/meetings/lpsc2017/pdf/1448.pdf would probably be going too far, but I think it would be good to have a small section on the controversy behind the definition. It's not universally accepted! WorldsWanderer (talk) 01:41, 4 September 2018 (UTC)
 * Yeah. I'm sure they do. But they're two people. One of whom has a VERY personal interest in this particular issue. Only designated authorities have the final say on issues of nomenclature. For astronomy, that's the IAU; for geology, i's the IUGS. Believe me, if the IUGS voted to accept the definition, it would go in here topswitch. But it hasn't.  Serendi pod ous  09:07, 4 September 2018 (UTC)
 * I respectfully disagree with your view of the relation between IUGS and science. If your look at their mission they state that they are involved in ("fostering international agreement on nomenclature and classification..."). Fostering is not the same as legislating. Scientists are under no obligation to follow their decisions. The same goes for the IAU although I admit I didn't find an equivalent statement after a quick search. As for the motivation, please don't impart motivations to one of the authors (I assume you mean Stern). Yes, he's been an advocate for Pluto to be recognized at the same level as other planets. You may argue that it's because he's the PI of the New Horizon mission. However, New Horizon is en route to Ultima Thule. He's not advocating for that to be planet. Others on the team have strongly supported the IAU definition (e.g. Rick Binzel). One of the most vocal supporters of the IAU definition is (Mike Brown), whose Tweeter handle is "Plutokiller" and wrote a book "How I killed Pluto". Could he have a vested interest in the topic? Also, the issue is not just about Pluto: all dwarf planets would be included in any of the other definitions. There are other opponents of the IAU definition (see the previous references I listed, and thanks for pointing the better way to include a reference in the Talk page). I don't want to take down the IAU definition, but I think we do a disservice to the Wikipedia users if we don't recognize that this definition is not universally accepted by scientists. A significant fraction of the community does not agree with the perception that there are two "levels" of planets and has gathered several times to discuss the issue. WorldsWanderer (talk) 20:49, 6 September 2018 (UTC)
 * I think the current article makes clear the changing definitions of "planet" (which once included the sun and moon). The IAU definition is supported by major dictionaries.  Dbfirs  21:18, 6 September 2018 (UTC)
 * I Agree with WorldsWanderer; the non-IAU definition is worth at least a mention on the article even if it doesn't have the same weight as the IAU definition. People reading the article should at least be aware that the issue of planetary definition isn't a settled one. Just because the IAU is an authority doesn't necessarily mean they're right. LumaP15 (talk) 00:08, 7 September 2018 (UTC)
 * Just because the IAU is an authority doesn't necessarily mean they're right. It does for Wikipedia's purposes. We seek verifiability, not truth. –  Juliancolton  &#124; Talk 00:16, 7 September 2018 (UTC)
 * It's already there (belt planets), don't need it twice. Tbayboy (talk) 14:17, 7 September 2018 (UTC)
 * It would be better though if the geophysical definition of "planet" were mentioned in more sections. For example, planets such as Ceres and Titan (objects considered to be "planets" under the geophysical definition of "planet") should have their images/photos at the top of the article alongside the photos of the "8 planets". And the section about the Solar System should have a sub-section in which more than 8 planets are described (i.e. Europa, Titan, Pluto, Ceres, Eris, the Moon, etc.) In other words, the IAU definition of "planet" should not be treated as a "fact" — the article, as it is currently written, treats it as a "fact". The first sentence of the article is straight from the IAU. There should at least be sentences at the beginning of the article (in the lead) acknowledging that this is not a closed issue and that there is still discussion in the scientific community about what the definition of a "planet" is (including definitions which do not conform to the IAU's definition). Also, instead of a sentence saying "there are 8 planets", the sentence should say "according to the IAU, there are 8 planets". Similarly, when describing a planet's defining characteristics (as defined by the IAU), the sentence should say "according to the IAU, a planet is [...]" The sentence should not say "A planet is [...]" (which is the way the first sentence of the article is written). LumaP15 (talk) 02:08, 7 October 2018 (UTC)
 * The IAU def is a fact: they defined it, and they are the accepted body for such definitions. There is no equivalent geophysical definition -- see Serendipodous' comment above. If IUGS ever makes a definition, it should be incorporated here, but not until then. Tbayboy (talk) 14:32, 7 October 2018 (UTC)
 * I disagree — the IAU definition is not a fact, it is an interpretation by one political body (the IAU) which not everyone agrees with. And the definition itself was not even chosen by a majority of people in the IAU. By saying phrases such as "there are 8 planets", the article is giving too much weight to this organization. A large political body's interpretation (IAU, IUGS, etc.) is not necessary. While the IAU is large enough that its version of planets should be included, the geophysical version (which is supported by individual planetary scientists) should be given more weight. LumaP15 (talk) 03:23, 17 October 2018 (UTC)
 * The 2006 IAU definition is the established scientific convention. Obviously this article should describe the established scientific convention.  Perhaps a brief mention that some scientists are unhappy with it is warranted, but it is no more than a temporary footnote in the history of planetary science (e.g., does anyone remember those who complained when Ceres and Vesta lost their planetary status?).  This situation is similar to the convention for Earth's prime meridian.  Some scientists dislike the established convention, but we don't rewrite wikipedia to give more weight to the Paris meridian.  Some may disagree with the established values of some physical constants, but we don't rewrite wikipedia to give more weight to alternate values.  So, no, the 2006 IAU definition does not have too much weight – it has the weight it obviously deserves, and we should not be rewriting wikipedia.  People who wish to battle for 9 or more planets in the Solar System can take this fight to the IAU.  JeanLucMargot (talk) 04:35, 17 October 2018 (UTC)
 * Read this link — it says that planetary scientists regularly disregard the 2006 IAU definition. In the article, the cited paper says "We therefore conclude that the argument made during the IAU planet definition controversy, that planet-sized Kuiper Belt Objects should be classified as non-planets because they share orbits, is arbitrary and not based on historical precedent." The article also says the IAU definition "communicates the wrong idea" about the nature of the Solar System.


 * Also, the following was said in the article: "This is why we aren't supposed to vote in science. Voting creates biases. Taxonomical classification is a part of science, so we should not allow biases to enter in. That is why it was a mistake to vote on the definition of a planet. It should have never happened." The article also says the 2006 IAU definition "was voted on by a very small percentage of the world's astronomers and planetary scientists". Why should the Wikipedia article about planets give so much weight to a definition that only a very small percentage of the world's astronomers and planetary scientists voted on?


 * The 2006 IAU definition of a planet was a political decision, not a scientific one. As you said ("perhaps a brief mention..."), there should at least be a mention of the opposition to the IAU defintion, so a mention of the geophysical definition of "planet" should be made at the beginning of the article. The Solar System section should also be changed so that there are two sections: one which describes the IAU's version, and one which describes the geophysical version. Also, any mention of "the 8 planets" should be written as "according the the IAU, the 8 planets..." LumaP15 (talk) 03:06, 18 October 2018 (UTC)


 * I think some of you are discussing this matter as if it were an empirical question. It is not, it is merely definitional. Different bodies are planets according to different definitions of the word. And it can be defined arbitrarily because "planet" is not a natural kind (even people involved with the demotion of Pluto, such as Gonzalo Tancredi, have admitted this). --ExperiencedArticleFixer (talk) 18:53, 26 July 2019 (UTC)
 * You're missing the point. It's not Wikipedia's job to make a call on which is the more valid definition. We go with the definition endorsed by the highest authority, in this case, the IAU. If the IUGS endorses Stern's proposal, then it can be included as a co-equal definition. But it has not.  Serendi pod ous  18:26, 27 July 2019 (UTC)
 * I'm not sure if you are talking to me, but I fully agree with what you said here and my comment is fully compatible with yours, so if you are talking to me I'm not sure which point you think I'm missing. --ExperiencedArticleFixer (talk) 19:55, 27 July 2019 (UTC)
 * who's the authority on who is an authority? 2600:1014:B06F:7793:E0FD:16C4:A6C1:42A (talk) 19:05, 14 September 2022 (UTC)
 * The IAU doesn't know what they are talking about what so ever. Planets (even dwarf planets/exoplanets) are evolving stars, dead stars and stellar remains. This has been known for about a decade now.https:// vixra.org/pdf/1205.0107v9.pdf "In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual."Airpeka (talk) 14:45, 29 March 2021 (UTC)
 * Not an acceptable source, — Paleo Neonate  – 14:39, 18 April 2021 (UTC)

Planet Eris
Why isn't Eris among the objects formerly considered planets in that section? Eris was considered a planet by many including NASA and still is by people rejecting the IAU definition. 212.186.0.174 (talk) 06:08, 9 August 2019 (UTC)
 * Not officially and for a very short time only. Ruslik_ Zero 06:53, 9 August 2019 (UTC)
 * Eris is still officially recognized by NASA as a dwarf planet. So technically is still a planet just smaller and belongs on this page. Liebecon (talk) 03:13, 9 May 2021 (UTC)
 * Dwarf planets are not a subcategory of planets, they are separate. While some would argue they should be considered a subcategory, myself included, that does not change the classification as it stands. Hi529 (talk) 17:15, 1 December 2021 (UTC)

Are these even planets? They could be more than Pluto will ever be
15760 Albion (image on the right) and (181708) 1993 FW are the two bodies in question.

"two newly discovered planets are called Smiley and Karla."ISBN 978-1-84239-912-5 I searched those two bodies up and it turns out they refer to the bodies listed at the very top, discovered by David C. Jewitt and Jane X. Luu. These bodies do orbit the Sun and do appear to be round despite their small dimensions. They may not have cleared their Kuiper Belt neighbourhood (this is being debated on, see clearing the neighbourhood) but unlike Pluto their orbits appear satisfyingly circular and not as eccentric.

I know I and my source are probably the only ones in the world shouting about these two bodies being planets, but unlike Pluto I classify them both as legitimate planets in a ten-planet Solar System. Should we debate over these being planets? Honestly, even though I see Pluto as a dwarf planet or even a binary comet or asteroid I don't think we should always follow the IAU.

46.107.124.47 (talk) 06:00, 9 October 2019 (UTC)
 * They're not planets; they're not even dwarf planets. Whoever called them planets was being either careless or facecious. And in future, don't put refs in talk page comments; they stay at the bottom no matter how long the page gets.  Serendi pod ous  09:22, 9 October 2019 (UTC)

"Escaping the Earth" listed at Redirects for discussion
An editor has asked for a discussion to address the redirect Escaping the Earth. Please participate in the redirect discussion if you wish to do so. Steel1943 (talk) 19:16, 23 January 2020 (UTC)

"Planet-sam" listed at Redirects for discussion
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 * Ok
 * ￼p 176.48.94.101 (talk) 08:11, 4 May 2024 (UTC)

Semi-protected edit request on 17 May 2020
1. Add the template to the section "Objects formerly considered planets" linking to the main article: List of former planets 2. Change "was ruled by Aphrodite, the goddess of love" in section "Mythology and naming" to "was ruled by Aphrodite, the goddess of love, and Hera, the queen of the gods" with source thanks 2407:7000:A2AB:D00:51C0:E732:65B0:DA84 (talk) 06:23, 17 May 2020 (UTC)


 * 1 is ✅, but #2 is ❌. The source given is not reliable. –Deacon Vorbis (carbon &bull; videos) 14:58, 17 May 2020 (UTC)

"Space Planet" listed at Redirects for discussion
A discussion is taking place to address the redirect Space Planet. The discussion will occur at Redirects for discussion/Log/2020 May 18 until a consensus is reached, and readers of this page are welcome to contribute to the discussion. TheAwesome Hwyh  13:24, 18 May 2020 (UTC)

Semi-protected edit request on 3 July 2020
A newly discovered planer Premsagar1997524 (talk) 05:42, 3 July 2020 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate.  JTP (talk • contribs) 07:11, 3 July 2020 (UTC)

Ref and historical summary for IAU def
I think this might be a good general ref for either this article, definition of 'planet', or our article on the IAU definition of 'planet'. I don't see it in any of them, but IMO it might make a useful counterweight to the claims that the IAU didn't adequately consider astronomer's views.

Ron Ekers (2018) 'The Prague IAU General Assembly, Pluto and the IAU processes'. In C. Sterken, J. Hearnshaw & D. Valls-Gabaud, eds., Under One Sky: The IAU Centenary Symposium. Proceedings, IAU Symposium No. 349.

It does note that there were 3 conceptions of 'planet' under consideration, something that seems to have gotten lost in our articles -- the traditional 9 plus Ceres and a couple more TNOs, the Classical 8, and the Sterns concept including moons. — kwami (talk) 05:40, 24 October 2020 (UTC)


 * did they really use the term "classical 8"? if so, that was kinda bogus of them..in classic times, there were only 5. (the sun and moon were NOT originally considered planets, but they sort of came to be considered planets in late/post classical times, but even then not fully). Uranus, Neptune, and Pluto were all discovered in modern times...so to call Uranus and Neptune classical seems a bit arbitrary Firejuggler86 (talk) 07:58, 4 January 2021 (UTC)

Stern and the alt def of 'planet'
Thought I should give some of my reasons here. We often equate the non-IAU def with Alan Stern, because he's vocal and is the head of New Horizons. But he badly contradicts himself, criticizes the IAU for adopting his own proposals (e.g. for claiming that Neptune had cleared its neighborhood, claiming that if it had, Pluto wouldn't be there -- despite his lambda criterion being in complete accord with the IAU), counts hundreds of known TNOs as dwarf planets when his colleagues/collaborators have shown that most are not even solid bodies, etc. So e.g. in the table of former planets, we need to be careful when stating that a body fits "the" geophysical definition, because there isn't just one, and even restricting ourselves to a single researcher, the def changes from year to year. — kwami (talk) 03:23, 13 November 2020 (UTC)
 * Well that raises the question of whether we should include the geophysical definition at all. If, as you say, it changes all the time, then the logical thing to do would be to appeal to a higher authority, like we do re: the definition of the Kuiper belt. But in this case there is no higher authority.  Serendi pod ous  06:13, 13 November 2020 (UTC)
 * Agree with . Double sharp (talk) 08:04, 3 June 2021 (UTC)

Moon not in hydrostatic equillibrium?
Could we get a citation needed (or better yet, a citation) for that? The Moon is clearly rounded under its own gravity, unless there's some very specific reason to consider it otherwise it is in equillibrium at least as much as the Earth is. — Preceding unsigned comment added by 185.206.227.142 (talk) 23:10, 20 February 2021 (UTC)
 * ✅ corrected and cited. Geogene (talk) 00:38, 21 February 2021 (UTC)
 * That citation, on the other hand, includes "~110" geophysical planets and shows the ones smaller than Earth and Venus in a picture. Including Huya, which according to current thinking is probably not a solid body and hence not in equilibrium. And including Iapetus, which is not actually in HE now (it's too oblate for its current rotation period). And including Pallas, Vesta, and Hygiea. So I'm unconvinced. Stern certainly considers the Moon a planet, but whether his definition as stated actually agrees with his intent is in question. Double sharp (talk) 07:32, 3 June 2021 (UTC)

The citations for the Moon not being in HE are at List of possible dwarf planets. That said, one of those papers says that Mercury and Venus are not in HE either. On the other hand, HE is part of the IAU definition, so if that's correct, then they are not planets. I don't think anyone actually believes that. After all: dynamically speaking, Mercury and Venus are clearly gravitationally dominant objects within their spheres of influence. And besides: as Soter remarks: "In a population of small bodies spanning a continuum of sizes and shapes,does gravity dominate the shape of a body if the cross-section deviates from hydrostatic equilibrium by 10%, or by 1%? Nature provides no unoccupied gap between spheroidal and non-spheroidal shapes, so any boundary would be an arbitrary choice."

I kind of suspect that each side already knows what kind of things they want to be planets and just has a problem finding a formal definition. It's just that the geophysical definition has bigger problems with edge cases, so far as I can see. Double sharp (talk) 08:03, 3 June 2021 (UTC)


 * Luna is not in HE: . It's too oblate for its current spin. That said, Stern's definition includes it anyway (the Runyon article cited explicitly includes it). The article by Runyon, Stern et al. being cited even goes so far as to include Proteus in its picture, which is not even round.
 * But then again, the Runyon et al. definition doesn't say HE. It says a planet "has sufficient self-gravitation to asssume a spheroidal shape adequately described by a triaxial ellipsoid". (OK, never mind that not all spheroids are ellipsoids.) So, I suppose the column should really be asking if the object is round, rather than for HE. No, I cannot come up with an explanation of what Proteus is doing in that figure.
 * We should, however, be consistent. Iapetus is in pretty much the same situation Luna is in: gravitationally rounded, but not in the correct shape for its current spin. Stern includes it as a planet too. So we should probably not give different answers for Luna and Iapetus in this table. Double sharp (talk) 15:23, 19 August 2021 (UTC)
 * you should try to fix the table as you think best. I think part of the problem might be that the article gives too much attention (weight) to minority viewpoints on what the definition of a planet should be. Geogene (talk) 18:08, 19 August 2021 (UTC)
 * I fixed the table to follow what Stern actually seems to be writing, which is closer to gravitational rounding than strict HE: 2002 The proposed criteria for admitting (or rejecting) any body into (or from) the class of planetary bodies has many attractive features, most notably the shared physical attribute that the bodies which meet the criteria are shape-dominated by gravity, but not so large as to ever have or in the future generate energy via a fusion chain reaction; 2017 A planet is a sub-stellar mass body that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by a triaxial ellipsoid regardless of its orbital parameters. Double sharp (talk) 08:58, 20 August 2021 (UTC)

Problem is, according to that definition Jupiter is not a planet, because the geometry is a contradiction in terms (no spheroids are triaxial ellipsoids). But we now have a better-written article to use. — kwami (talk) 12:21, 9 January 2022 (UTC)

Symbols for 'new' dwarf planets
So some guy has created his astrological symbols for dwarf planets discovered in 21st century. Nice, imaginative, but what about notability? It looks like pure original research. Szczureq (talk) 12:06, 9 January 2022 (UTC)
 * They're the default in astrology (which is the only place planetary symbols are common) and have been accepted into Unicode. He actually created a few more, but they are not notable. — kwami (talk) 12:17, 9 January 2022 (UTC)

Issues
What makes this article to be FA when it has uncited sentences and an expansion template. 2001:4455:364:A800:E5E5:3906:820:3691 (talk) 00:55, 27 January 2022 (UTC)


 * There are currently 47 cn tags. (t &#183; c)  buidhe  00:20, 6 February 2022 (UTC)


 * I look through the majority of "citation needed" tags, and it seems that a LOT of work is needed here. Some sections are good enough, but some (probably added after the FA nomination?) are in a great need of copyedit and sources (f.e. "21st century", "Geophysical definitions", "Mythology and naming", "Formation"). Section "Solar System" has 10 'cn', though it's mostly a list of planets with one-sentence intro of planet types. "Exoplanets" needs a rewrite and good sources. "Physical characteristics" has a "needs expansion" template. I never wrote a FA, but this one clearly fails even milder GA standards., you are more familiar with the process, so maybe you know what should be done. FAR is probably the answer, though maybe the article should be simply stripped of its featured status. Artem.G (talk) 17:10, 30 April 2022 (UTC)
 * Hi To delist an article it does need to go through FAR. Unfortunately, I wont' be able to nominate this for a while because there's a limited number of FAR nominations each editor is allowed at one time. I would encourage you to go ahead and nominate there; the process isn't too difficult. (t &#183; c)  buidhe  22:15, 30 April 2022 (UTC)
 * In case any page watchers have missed it: an FAR has been opened. XOR&#39;easter (talk) 23:03, 7 May 2022 (UTC)
 * There are some new comments over on the review page, just in case anyone is watching here but not there. Input most welcome. XOR&#39;easter (talk) 16:55, 10 July 2022 (UTC)

Science
Hi there is actually 1000 million planets in the solar system because the different types of solar systems 86.13.15.62 (talk) 19:01, 20 May 2022 (UTC)


 * You mean 'planetary system'. There's only one Solar system: the planetary system of Sol (the Solar planetary system). Though some people get sloppy and say 'solar system' for 'planetary system', the way some people say 'Kleenex' for 'tissue', 'Hoover' for 'vacuum cleaner' or 'Coke' for cola. — kwami (talk) 00:28, 24 June 2022 (UTC)

Tables
I'm a little concerned that the article currently has too many small tables floating about, listing what bodies counted as which type of planet at which time. It makes sense to present this in a tabular way for at-a-glance reference, but spreading it across multiple boxes partly defeats that purpose. The repetition of symbols also seems like overkill. Perhaps the multiple tables can be consolidated somehow? XOR&#39;easter (talk) 20:05, 23 June 2022 (UTC)


 * It would be difficult to combine them because they have different numbers of columns. It would also be hard to give an overall list of bodies with dates, because there's no clear cut-off for many of them. (E.g., when did Ceres stop being counted as a planet? Or Io?) — kwami (talk) 00:23, 24 June 2022 (UTC)


 * I don't think the tables in the History section add much (if any) value. Praemonitus (talk) 17:09, 10 July 2022 (UTC)
 * I don't think they add anything, and in fact, think they are actually just disrupting the flow. The symbols certainly aren't needed. If someone could find a way to make an overall depiction, that would be helpful, but it sounds like that would be hard to do. Sandy Georgia  (Talk)  05:08, 11 July 2022 (UTC)

Planetary-mass Moons table
This section of the article starts by stating that all planetary-mass moons are synchronous (tidally locked) and that their orbital period equals their rotational period. My understanding is that there are many solar system moons that ARE NOT tidally locked, and therefore would have a different rotation to orbit ratio. Hyperion of Saturn is not tidally locked. The moons presented in the table however may be incomplete, and therefore excluded some of the asynchronous ones?

I think the table needs the rotation period column added, similar to the planet table above. I think it would be helpful to also add a column identifying which planet each moon belongs to in this table.

Reference - https://astronomy.stackexchange.com/questions/44688/moons-with-synchronous-rotation-in-our-solar-system SquashEngineer (talk) 18:28, 5 July 2023 (UTC)
 * Every planetary-mass moon (i.e. moon big enough to be gravitationally rounded) is tidally locked. Hyperion is not a planetary-mass moon. Double sharp (talk) 04:39, 6 September 2023 (UTC)

Semi-protected edit request on 30 December 2023
The introductory paragraph, which outlines NASA's definition of a planet, contains some grammatical errors. Please revise this paragraph by devoting a separate sentence to each criterion, and supplanting the numerical terms that precede them, like "firstly" and "second", with more formal or appropriate terms, like "additionally"; amending the writer's use of the contraction "it's" in place of the possessive "its"; and amending the writer's erroneous capitalisation of the term "planet". 2001:1970:529D:2600:81B1:24B3:D3BF:65AF (talk) 03:45, 30 December 2023 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Spintendo  23:18, 31 December 2023 (UTC)

First Caption Readability
The caption for the first image reads "The eight planets of the Solar System with size to scale (up to down, left to right): Saturn, Jupiter, Uranus, Neptune (outer planets), Earth, Venus, Mars, and Mercury (inner planets)" but with the directions given the ordering should be Saturn, Jupiter, Uranus, Earth, Mars, Neptune, Mercury, Venus. (This is because (up to down, left to right) implies you scan the image as vertical columns starting from the left and moving to the right.)

Even if the outer planets and the inner planets remained grouped in the caption, the inner planets should say Earth, Mars, Mercury, Venus.

Whatever, this caption needs to be changed to improve readability. 2600:1700:6E30:30B0:A1CD:CD28:3DCE:4BC9 (talk) 20:08, 15 January 2024 (UTC)
 * I agree with this; the caption is not at all clear ~ if i had not known which planet was which prior to looking at it, i would have been unable to figure it out as the up/down & left/right directions are neither clear nor accurately followed. As it's the very first thing one sees on coming to the page ~ from the main page today! ~ i suggest this be reworded. Happy days, ~ LindsayHello 07:08, 18 June 2024 (UTC)

Semi-protected edit request on 18 February 2024
Let’s Imagine you’re playing catch with a friend. When you throw the ball, it follows a path through the air until it lands back in your friend’s hands. That path the ball takes is like an orbit—it’s the path something follows as it moves around something else.

In space, orbits are everywhere. For example, Earth goes around the sun, just like the moon goes around Earth. Even things we humans make, like satellites, have their own paths around Earth. These paths aren’t straight lines; they’re more like stretched-out circles, called ellipses.

Its Very Important to Make Understanding on orbits. it helps us travel with space. Imagine trying to send a rocket to Mars without knowing. With understanding orbits, scientists and engineers can plan out the paths of spacecraft,

Orbits also help us learn more about space. The study of Scientists is  paths of planets, moons, and stars Give us understanding, how and Why they move. It’s like putting together a giant puzzle of the universe!

But orbits aren’t just about moving physically—they can mean other things too. Ever heard someone say they’re “in the orbit” of a famous person? That means they’re close to them or influenced by them. Orbits can also mean cycles, like the changing seasons of the moon.

Looking ahead, orbits will keep important. Imagine going on vacation to a hotel in space, where you can look out the window and see Earth below you! Or maybe one day we’ll get resources from asteroids by sending spacecraft around them.

Whether it’s planets moving or our adventures, orbits help us understand  About the the world. So, next time When you look up at the stars, take a moment to think about the amazing paths things take as they travel through space. Who knows we’ll discover as we keep exploring the wonders of orbits.

Why does Orbit Chandrayaan-3 revolve around the Earth?

In July 2023, India sent a mission to explore the Moon. They planned for a spacecraft called Chandrayaan-3 to land near the Moon’s south pole. It had a lander named Vikram and a rover called Pragyaan.

The mission started well, with Vikram and Pragyaan landing on the Moon in August 2023. But soon after landing, they lost contact with Vikram, so it couldn’t work anymore.

While Vikram and Pragyaan stayed on the Moon, another part of the spacecraft, called the propulsion module, stayed in orbit around the Moon. It was supposed to work for three months, but it had extra fuel.

To use this extra fuel and learn more, the Indian Space Research Organisation (ISRO) decided to bring the propulsion module back to orbit around Earth. They did this by making the module do some controlled moves between October and November 2023, and it safely entered Earth’s orbit.

Bringing it back to Earth’s orbit was important for a few reasons:

Testing: ISRO wanted to see how well the module worked. This would help them plan better for future missions to the Moon.

Looking at Earth: The module had instruments to study Earth’s air and surface. Staying in Earth’s orbit meant they could keep studying these things.

Saving Fuel: Bringing the module back to Earth’s orbit instead of letting it stay around the Moon meant they could use less fuel and control it better.

As of February 11, 2024, the Chandrayaan-3 propulsion module is still circling around Earth in a steady path. They haven’t said yet what they’ll do next with it, but they might keep studying Earth or let it fall back to Earth when it runs out of fuel.

Even though the part of the mission Orbit with the lander and rover didn’t go as planned, bringing back the propulsion module gives them more chances to learn and get better for future trips to the Moon.

''' Singhharjeet23 (talk) 07:19, 18 February 2024 (UTC)
 * Red question icon with gradient background.svg Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Justarandomamerican (talk) Have a good day! 12:11, 18 February 2024 (UTC)
 * Are you proposing a section on orbits in the style of a children's magazine? Not gonna happen —Tamfang (talk) 21:37, 4 May 2024 (UTC)

Planet-satellite distinction
Dear @Doublesharp,

I would like to improve the beginning of this article by following common usage and the recommendations of the International Astronomical Union (IAU) by writing something along the lines of:

A planet is a large, rounded astronomical body that is in orbit around a star, stellar remnant, or brown dwarf.

You reverted my proposed edit by arguing that the term "rogue planet" somewhat makes that ambiguous and that they are geophysical usages that include rounded satellites. I propose that we do not omit the essence of what makes a planet a planet but instead acknowledge edge cases where usage can extend the formal definition to other situations:

 The term rogue planet has been used informally by some astronomers to refer to free-floating objects. However, the IAU recommendations explicitly state that such objects are not planets.

Likewise, some planetary scientists have referred to satellites as planets, but it would be misleading to pretend that such usage is prevalent. The distinction between planets and satellites is generally recognized as profound, both in professional circles and in the public sphere. 

Wouldn't it be more appropriate for this article to describe the fundamental traits of a planet and then describe where usage may vary? I ask that you please reconsider your revert. Thank you.

JeanLucMargot (talk) 15:29, 11 June 2024 (UTC) JeanLucMargot (talk) 15:29, 11 June 2024 (UTC)


 * Personally, I'm fine with utilizing the IAU's adopted definition of a planet; we do similar with Dwarf planet and Minor planet, so why not here? The third paragraph of the lead already addresses parallel definitions/usages of "planet" in brief anyways (albeit not addressing the term "rogue planet"). ArkHyena (talk) 00:52, 12 June 2024 (UTC)
 * The thing about the IAU's definition for dwarf planets, though, is that the disagreement is of a different kind there. Planetary scientists who reject the IAU definition of planet would still agree that Pluto is a dwarf planet – after all, Stern is the one who coined the term. Where people disagree is whether dwarf planets are also planets or not. The case for "planet" is somewhat different, where planetary scientists often adopt a definition quite different from the IAU one, as evidenced by the Metzger cites. That's why I thought it might be better to start off with the things common to all common definitions before specifying things about the variations.
 * , do you have an opinion? Double sharp (talk) 04:40, 12 June 2024 (UTC)
 * The only consensus is that a planet is a large non-stellar / sub-stellar object.
 * There are some very good astronomers who reject the IAU definition, so using it would not be scientific consensus, but a bureaucratic one. Even then, the IAU doesn't have a coherent definition of 'planet', so we'd be parroting a faux-scientific definition.
 * I don't see where the IAU "explicitly states" that rogue planets are not planets.
 * AFAICT no-one in the last couple centuries has "referred to satellites as planets". Only satellites that meet the definition of 'planet' are considered planets. The distinction is most certainly not "generally recognized as profound".
 * (BTW, I prefer the IAU definition myself, and have argued against Stern's POV, including to planetary geologists who got rather annoyed, so I'm not pushing my preferences here. I just recognize that this is a bureaucratic wrangle with public-outreach and funding implications, not a scientific dispute.)

— kwami (talk) 04:58, 12 June 2024 (UTC)
 * Very fair! However, I'm still mildly concerned about the potential ambiguity the current lead introduces; the first paragraph in particular introduces planets under the broadest definition but then immediately states that there are only eight (known) planets in the Solar System as per the IAU definition (with the potentially confusing term "at least"). Though clarified at least partially later in the article, I believe this could be handled better. This may be a minor issue, and one quite difficult to reconcile at that, so at this moment I don't have a better solution to propose. Hopefully someone does though. ArkHyena (talk) 07:02, 12 June 2024 (UTC)
 * Yes, that is problematic. The wording "The Solar System has at least eight planets" is bad. I assume that's to accommodate the various definitions, but it sounds instead like we're saying there are undiscovered planets out there. I think it might be better to say something like "The Solar System has eight planets by the most restrictive definition of the word." (And indeed, in the functional definition it actually uses, the IAU does say there are "eight planets".) — kwami (talk) 08:30, 12 June 2024 (UTC)
 * I've tried to address the problems alluded to by some changes to the lede; feel free to revert and/or improve it further. Double sharp (talk) 11:21, 12 June 2024 (UTC)
 * Thank you for sharing your thoughts. First, I am not suggesting that we lead with the IAU planet definition - it is vague and excludes exoplanets. However, the IAU has been the official professional organization in charge of planetary nomenclature for 100+ years, and we cannot just ignore their recommendations: (1) a planet orbits a star, stellar remnant, or brown dwarf (page 3, last paragraph ); (2) free-floating bodies are not planets ( page 4 page 2, item 3 ). This is the essence of a planet, regardless of one's opinion about whether dwarf planets are planets or not. This reflects the consensus, as demonstrated by perusing astronomy and planetary science textbooks. If you disagree, please show me a textbook that defines a planet as "a large, rounded astronomical body that is neither a star nor its remnant."  Second, I am interested in improving the accuracy and reliability of this article.  There are zero funding implications for me or, as far as I can tell, any other planetary scientist.  We study Solar System bodies because they are interesting, not because they happen to fall into one nomenclature class or another.  Third, I don't see the relevance of 6 citations to a paper that proposes that "Moons are Planets".  There are many, many more citations to papers that adopt the centuries-old distinction between moons and planets.  It's certainly fine to indicate that some scientists espouse this unusual view, but it does not seem appropriate to torque the established meaning of planet to include every point of view about what a planet is (Would Wikipedia define "energy" in the same way?). Fourth, it may not be wise to present the theory of planet formation in the definitional paragraph. It is usually considered best practice to separate definitional issues from hypotheses that may or may not be correct.  Consider presenting formation ideas in a separate paragraph.  Finally, I am generally okay with the term "most restrictive definition of the word", but in all fairness it should probably state something like "most restrictive and IAU-sanctioned definition of the word", because that is what the reality is.  Thank you. JeanLucMargot (talk) 16:06, 12 June 2024 (UTC)
 * The Metzger paper contains an appendix, giving forty-three pages of citations to papers calling satellites planets. If you want a text, Krasnopolsky's 2019 text Spectroscopy and Photochemistry of Planetary Atmospheres and Ionospheres has a subtitle explicitly including Titan and Triton (as well as Pluto, of course). So I'd argue that the satellite-including definition is essentially established in its own subfield, and deserves to be noted as an ambiguity.
 * I do agree that the definition should be separated from the formation, and have made changes to that effect. Double sharp (talk) 16:27, 12 June 2024 (UTC)
 * Thank you for considering the proposed changes. I think it's fair to describe the ambiguity after describing the consensus. Please note that the textbook you mention makes an explicit distinction between planets and satellites in section 1.1.  One can speak about Titan's planetary atmosphere without labeling Titan a planet.  Here are a few more examples: (1) widely used intro-level astronomy textbook by Bennett et al. (2009): a planet is "a moderately large object that orbits a star and shines primarily by reflecting light from its star".  (2) Oxford University's A Very Short Introduction title on Planets by Rothery (2010) describes how the IAU's "non-controversial" criterion for planethood ("it must be in orbit about the Sun") rules out large satellites such as our own Moon. (3) The volume "Planets and Moons" of the Treatise on Geophysics (2009) adopts the IAU definition. (4) The graduate-level "Dynamics of Planetary Systems" by Tremaine (2023) describes the IAU definition.  I have not found a single textbook that defines a planet in the way that it is defined here.  Please consider improving the first sentence and noting alternate uses of the word later on.  Thank you.  JeanLucMargot (talk) 16:49, 12 June 2024 (UTC)
 * The Metzger supplementary information is a gross mischaracterization of the situation. Just because people write things like "planet-scale magnetic field" or include the Moon in a chapter on terrestrial planets does not mean that they equate planets and satellites! In fact, if you asked almost all of the scientists quoted how to label the Moon or Europa, they would say that they are satellites, of course. JeanLucMargot (talk) 18:37, 12 June 2024 (UTC)
 * As for free-floating bodies not being planets, "it must be emphasized that [it] remains a working definition." Many astronomers simply call them planets.
 * As far as funding implications, I've spoken to several members of the NH team who objected to the 'demotion' of Pluto, and one of their primary concerns was funding. If Pluto's a planet, it deserves a space mission; if not, it doesn't (according to congressional priorities in the US). They were relieved that the IAU redefinition didn't happen until after the launch of NH. — kwami (talk) 18:40, 12 June 2024 (UTC)
 * Looking at your compromise in the lead, it does read quite unwieldy as one sentence. Perhaps an alternative compromise could work, splitting it into two sentences:
 * A planet is a large, rounded astronomical body that is neither a star nor a stellar remnant. Planets are generally—though not universally—considered by astronomers to orbit a star, stellar remnant, brown dwarf; or float freely in interstellar space.
 * This should address both broad and stricter definitions whilst including FFPs, who seem to be called "planets" at least occasionally in literature but certainly are viewed and known as "rogue planets" by much, if not a majority of the public. As a note, since it looks like information on planet formation is going to be kept separate from the first paragraph, more elaborate wording could be used to clarify conflicts in definition.
 * and, what are your thoughts on the above? ArkHyena (talk) 20:41, 12 June 2024 (UTC)
 * Respectfully, I don't see it as an improvement to define things by what they are not. One would then have to add "neither a star, nor a stellar remnant, nor a brown dwarf, nor a dense core, nor a satellite" and every other large round celestial object we discover in the future. I would propose
 * A planet is a large, rounded astronomical body that is generally though not universally accepted to be in orbit around a star, stellar remnant, or brown dwarf.
 * This wording includes free-floating bodies and even admits the more exotic uses of the term planet.

Please see proposed edit to capture all viewpoints without sacrificing fundamental aspects. JeanLucMargot (talk) 18:01, 12 June 2024 (UTC)


 * Awkward. Sounds like if it is universally accepted as orbiting a star, then it's not a planet. — kwami (talk) 23:11, 12 June 2024 (UTC)
 * No, that's not what that sentence means. If that sentence is too complex, we could write
 * A planet is a large, rounded astronomical body that is generally accepted to be in orbit around a star, stellar remnant, or brown dwarf.
 * This simplified wording still includes free-floating bodies and still admits the more exotic uses of the term planet.
 * This wording is fine with me, since "generally accepted" would include "universally accepted". Double sharp (talk) 08:13, 14 June 2024 (UTC)
 * But why say it at all? It just means a planet that's in orbit around a star, and so excludes rogue planets. But 'generally accepted' means that whether or not it's a planet depends on its acceptance as a planet, not on whether it fits the definition of a planet. Thus it may be a planet today but will no longer be a planet next year.
 * I know that's not what is meant, but that's what it says. — kwami (talk) 08:18, 14 June 2024 (UTC)
 * The sentence says what we mean to say, and it does not exclude free-floating bodies ("rogue planets"). This wording is suggested for two reasons: (1) it's better to define a concept by describing what it is rather than describing what it is not (e.g., it's better to say "a small metal spike with a broadened flat head, generally driven into wood with a hammer" than "a small metal spike that is not a screw nor a rivet nor a pin") and (2) it conveys the defining feature of 'planet' accepted in popular culture, astronomy textbooks at all levels (see specific quotes above), the overwhelming majority of peer-reviewed articles, and the professional organization in charge of planetary nomenclature, while still allowing for deviations from the typical situation (e.g., planets that have been ejected from their planetary system) and even unconventional characterizations (e.g., "moons are planets"). If others believe that this formulation is superior to the current one ("A planet is a large, rounded astronomical body that is neither a star nor its remnant nor a brown dwarf"), please make the change, preferably citing . Thank you. JeanLucMargot (talk) 22:10, 14 June 2024 (UTC)
 * As currently worded, it says that if a body is not generally accepted as orbiting a star, then it's not a planet -- even if it does orbit a star. That is, whether a body is a planet does not depend on reality, but on our perception of reality. Its nature changes as our perception changes. AFAIK, no astronomer uses such a definition. — kwami (talk) 22:22, 14 June 2024 (UTC)
 * Thank you, that is a fair point. Required is a better word.
 * A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf.
 * The adverb "generally" conveys the usual requirement while allowing for free-floating bodies ("rogue planets") and unconventional characterizations (e.g., "moons are planets"). JeanLucMargot (talk) 04:56, 15 June 2024 (UTC)
 * Yes, that's better. I'm still not happy with it, because my response in reading it would be 'who gets to dictate the planets?', but I can't think of better wording, so I think for now it's good enough. — kwami (talk) 05:05, 15 June 2024 (UTC)
 * I think this is good too. And since we're now all in agreement, I've edited the lede so that it starts with this text. Double sharp (talk) 12:37, 15 June 2024 (UTC)
 * I think removing the mention that they cannot be a star or its remnant removes a pretty vital criteria for planethood that everyone seems to agree upon - otherwise, a secondary star or a brown dwarf can also be considered a planet. I think we should consider adding it back in some form.
 * A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself.
 * Probably could use a better wording. AstroChara (talk) 16:52, 18 June 2024 (UTC)
 * This problem may resolve itself once we quantify "large" (e.g., < 13 Jupiter masses). In the meantime, perhaps "and has not undergone nuclear fusion"? JeanLucMargot (talk) 23:51, 18 June 2024 (UTC)
 * As noted at Planet, the 13 Jupiter mass limit is not universally accepted, and some would include brown dwarfs beyond that limit as planets. Double sharp (talk) 16:10, 19 June 2024 (UTC)
 * Indeed, which is why I think simply adding this clarification is the best solution, as it directly excludes stars and brown dwarfs without going into the specifics of what the criteria is - something that I heard also has its own variants. AstroChara (talk) 05:38, 20 June 2024 (UTC)

WP:ERRORS
FYI, the changes discussed above have triggered some discussion at Main_Page/Errors while the article appears on the main page. Andrew🐉(talk) 15:37, 18 June 2024 (UTC)

Short description
Surely a planet is spherical, not round? Roundtheworld (talk) 18:24, 18 June 2024 (UTC)


 * No planet is spherical; all planets deviate from a sphere to varying degrees due to topography, tidal influences, and deformation due to rotation. Saturn is the most apparent example of this of the classical 8, and Haumea and Quaoar are even more extreme if you include dwarf planets. Planets are best approximated by Maclaurin spheroids and Jacobi ellipsoids instead. ArkHyena (talk) 18:57, 18 June 2024 (UTC)
 * @ArkHyena In that case, as one dictionary definition of "round" is "shaped like a sphere", I come back to my point that "round" should not be used in the short description. I note that the word "round" does not appear in the article. Roundtheworld (talk) 11:40, 19 June 2024 (UTC)
 * It is one of the definitions, but I don't believe it is the primary definition. "Round" has very broad usage, and here I'd say its usage is appropriate. Alternative/more specific terms, such as "spheroidal" or "ellipsoidal" are relatively obscure, and I would argue would only act to confuse someone reading the shortdesc without an explanation for what a spheroid or ellipsoid is. Per WP:SDJARGON, this should be avoided; the specifics of what shapes planets are can be (and should be) adequately explained in the maintext. ArkHyena (talk) 19:45, 19 June 2024 (UTC)

IAU definitions
I updated the definition in the first paragraph to track (a) the cited source, and (b) the common understanding of the term "planet." My text reads:


 * A planet is an celestial body that is in orbit around a star, stellar remnant, or brown dwarf, that has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a spherical or nearly spherical shape, and that has cleared the neighborhood of its own orbit of other bodies. The Solar System has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune.

There are two reasons for the change.

(a) First, NOBODY believes the definition that I reverted away from. Ceres meets that definition. All the larger moons meet it (including Charon). Do we all agree that Ceres is not a "planet?" That Charon is not a planet? If so, then "spherical" and "orbiting a star" isn't enough to define "planet." Do we all agree that definitions oughtta be correct, neither overinclusive nor overinclusive? If there's some disagreement on that principle, what's the basis? What's the rationale for a definition that is clearly wrong because it is clearly overinclusive?

(B) the very source cited in the text I revered away from, Lecavelier des Etangs, The IAU working definition of an exoplanet, says:


 * The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System, which is a mass sufficient both for self-gravity to overcome rigid body forces and for clearing the neighborhood around the object’s orbit.

In other words, the definition I reverted away from violated "reliable source."

I am happy to have anyone fix up any error in what I proposed. But @Artem G, what interest is served by introducing error?

DCLawwyer (talk) 21:09, 19 June 2024 (UTC) DCLawwyer (talk) 21:09, 19 June 2024 (UTC)


 * Considering that the text makes a mention of "the most restrictive definition of the term", I wonder if a compromise could be made by including these criteria in that sentence. This could be implemented as either a link to the IAU definition, or by adding the mention of the two dynamical criteria (which are not universally agreed upon) in it. AstroChara (talk) 05:28, 20 June 2024 (UTC)
 * (A) is not true. The geophysical definition, which explicitly includes dwarf planets and larger moons, is in quite common use among planetary scientists. Double sharp (talk) 07:55, 20 June 2024 (UTC)


 * @AstraChra and @Double sharp:  These two comments turn "reliable sources" and "neutral point of view" and "consensus" on their heads.  The IAU formulated a definition.  Both documents that purport to have IAU blessing include "clearing the neighborhood around the object’s orbit."


 * "Consensus": does not require "universally agreed" or no outlier "common use." The source that the article purports to cite, footnote 1, Lecavelier, states "clearing the neighborhood around the object’s orbit" is part of the definition.  Neitehr @AstraChra and @Double sharp give any rationale for departing from that professional consensus.  A few outliers are no more relevant here than a few outliers form a rational basis to disregard climate change.  DCLawwyer (talk) 13:11, 20 June 2024 (UTC)
 * you definitely believe that all professionals prefer IAU definition, and that surely is wrong, because a lot of planetary scientists prefer the geophysical definition, completely ignoring this "professional consensus". By your logic, they all are as wrong as climate change deniers, right? Artem.G (talk) 13:33, 20 June 2024 (UTC)


 * I believe in an article that tracks its cited sources. and I believe in a collaboration in which the parties actually read their sources. That's the fundamental disagreement.  Please stop changing the subject.  DCLawwyer (talk) 13:42, 20 June 2024 (UTC)
 * This is a flawed statement. Yes, there is astronomical consensus for the IAU definition of a planet, but proposing the IAU definition to be front and center would make sense only if astronomy was the only/primary field concerned with planets and planetary characteristics. It is not. As Double sharp points out, planetary science ofter favors more liberal definitions of what is a planet, regardless of the IAU definition. For concrete examples:
 * Ceres orbits the Sun and is large enough in size to have experienced many of the processes normally associated with planetary evolution. Therefore it should be called a planet.
 * This makes Ceres similar to a small planet, and in fact it is thought to represent a class of objects from which the inner planets formed.
 * We also refer to the planets of the Kuiper Belt (KB) as dwarf planets (DPs), in analogy to giant planets or terrestrial planets. and We also consider satellites of planets that are large enough to satisfy the GPD to be planets that orbit other planets
 * ... these characteristics altogether making the Pluto system a fully planetary one.
 * This is far from exhaustive, and clearly is significant enough to warrant consideration throughout the article, including the lede.
 * I'd also oppose formatting the lede like this on comprehension and organization grounds. Per MOS:OPEN, The first paragraph should define or identify the topic with a neutral point of view, but without being too specific.. The layman reader is very unlikely to even be aware of the discrepancy between astronomy and planetary science re: planet definition, so IMHO it would be best to keep the intro paragraph restricted to planetary characteristics that both disciplines agree on, though still clarifying that multiple definitions are used (and therefore the Solar System only has 8 "major" planets per the IAU/conservative definition). ArkHyena (talk) 18:20, 20 June 2024 (UTC)


 * OK, but your sources here are not cited (at least not cited at the relevant point) in the article. The only source cited at the relevant point of the article uses the "cleared orbit" definition.  I don't know whether you can get away with sloppy cites in your discipline, but I can't in mine.  DCLawwyer (talk) 22:17, 20 June 2024 (UTC)
 * I myself have hardly contributed anything to the article, so I cannot comment on the adequacy of its sourcing in general. However, it seems that you haven't looked into the main text, where various citations back the fact that planetary scientists' interpretations of what is a planet are more liberal—particularly references 154, 201, 202, 4, etc. I mean, there's an entire subsection labelled "Criticisms and alternatives to IAU definition"; upon first glance, to me the content looks more than substantial and well-referenced enough to support mentions of alternative definitions in the lede. ArkHyena (talk) 23:41, 20 June 2024 (UTC)


 * The lede is supposed to summarise the article. Per MOS:LEDE, it does not need explicit citations as long as the statement concerned is cited in the article's body. Double sharp (talk) 04:32, 21 June 2024 (UTC)


 * @ArkHyena and Double sharp: Do you read carefully? at the relevant point of the article    at the relevant point of the article    at the relevant point of the article  You remark "into the main text" reads more like evasion of the question than a bona fide effort to address the question.  Double sharp, you say "as long as the statement concerned is cited in the article's body" -- can you point to something in any Wikipedia guideline, or are you making stuff up?  I don't know whether the two of you can get away with sloppy cites in your disciplines, but your explanations wouldn't hold water in mine. DCLawwyer (talk) 13:18, 21 June 2024 (UTC)
 * Double sharp quite literally did. If you would like somewhere more specific, see MOS:LEADCITE (which is within MOS:LEDE), which explicitly states Because the lead usually repeats information that is in the body, editors should balance the desire to avoid redundant citations in the lead with the desire to aid readers in locating sources for challengeable material. Given that there is an entire subsection dedicated to alternatives to the IAU definition, I believe readers should have an easy time locating said challangeable material. Whilst you're at it, I would also advise giving WP:AGF a good review. ArkHyena (talk) 16:10, 21 June 2024 (UTC)

Changes requested to the definition of planet ahead of the International Astronomical Union’s General Assembly
This is more of a situational awareness of something being presented to the International Astronomical Union’s General Assembly. It is thus not ready for primetime, but I thought that editors interested in this topic will want to monitor the news about this should the IAUGA make any changes. Peaceray (talk) 18:37, 13 July 2024 (UTC)
 * I'm very glad that this points out many things we previously did not have a source for. For example, we were previously unable to cite a source for the fact that around very low-mass stars, the mass threshold for clearing the neighbourhood may be lower than the mass threshold for gravitational self-rounding. :) Double sharp (talk) 04:01, 14 July 2024 (UTC)
 * Oh hey, this is neat! Seconding what Double sharp says, although I personally dislike one criteria (the lower mass limit, to be precise). I'm glad to see some work being done in writing down some of astronomy's frustratingly unwritten conventions, however. ArkHyena (talk) 21:44, 14 July 2024 (UTC)