Wikipedia:Featured article candidates/Planet Nine/archive1

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

The article was archived by Ian Rose via FACBot (talk) 00:58, 22 December 2018 [1].


Planet Nine edit

Nominator(s): Jehochman Talk 22:38, 13 November 2018 (UTC)[reply]

This article is about a hypothetical planet beyond Neptune. It hasn't been discovered yet, but there is considerable evidence that it exists. I am hopeful that this nomination will be thoroughly disrupted by the actual discovery of the Planet. Because of it's likely position in the Solar System, it is most likely to be observable from Earth in the late Fall and early Winter. Please read the article to learn more. It's absolutely fascinating and the best page on the Internet about this topic. We've gone through the toolkit and fixed whatever defects were pointed out. Surely there will be some more, but we have a good core of editors who will jump on any needed changes. It would be nice if this was an FA in time for the discovery. Up to now about 30% of the target area has been searched. By the end of this season about 70% will have been searched. Therefore, there is a 50/50 chance it will be discovered this hunting season, if it exists. Be sure to credit Agmartin (talk · contribs) for he has done the most work. Jehochman Talk 22:38, 13 November 2018 (UTC)[reply]

  • Probably best if you sort the [improper synthesis?] tag for FN 42.  Done
  • There are a few paragraphs or bullet points (mostly lower down in the article) that are unsourced: these should be sourced.
I have no knowledge of this subject, but I'll wrap a cold towel around my head and see how much I can understand! The bits I skimmed through are quite interesting, so I look forward to the rest. Cheers - SchroCat (talk) 23:02, 13 November 2018 (UTC)[reply]

Cas Liber edit

I'll take a look at this and jot queries below:

However, the infrared survey by the Wide-field Infrared Survey Explorer (WISE) may have the capabilities to detect such a planet - this is ambiguous. Does it mean a planet with the diameter of Neptune or 2-4x earth? Also should specify whether this is a past, repsent or future survey.  Done
the region with stable aligned orbits shifts... "stable, aligned orbits" or "stably aligned orbits"?
detection is a Really Big discussion point - I feel that more could be added on this topic.
— Preceding unsigned comment added by Casliber (talkcontribs) 03:06, 14 November 2018 (UTC)[reply]

more later.

Comments by Dunkleosteus77 edit

Not really. For one, there's a range of possible masses for super-Earth's. And then, removing the super-Earth reference takes away the important information what class of planets it belongs to. So, both refer to different bits of information (maybe one specifying the other). Renerpho (talk) 06:42, 18 November 2018 (UTC)[reply]
Agree with the comment above.  Done
We don't know where it is right now (it would be easy to find if we did). We know it's not at 200 AU since that makes it too bright to have escaped detection, but it may be anywhere between a few hundred and well over 1000 AU. Statistically, it is likely near its aphelion well beyond 700 AU. Renerpho (talk) 06:42, 18 November 2018 (UTC)[reply]
I didn’t get that at all from the text   User:Dunkleosteus77 |push to talk  18:14, 19 November 2018 (UTC)[reply]
@Dunkleosteus77:, In the Detection Attempts section the range of present locations is explained. Since I've reorganized the article, could you take a second look and see if this is sufficient? Jehochman Talk 15:37, 10 December 2018 (UTC)[reply]
In the article, you need to start explaining things like you just explained to me how far away the planet is from the sun above, otherwise only experts on the subject or with a deep understanding with astronomy will be able to understand this article   User:Dunkleosteus77 |push to talk  14:42, 11 December 2018 (UTC)[reply]

Thank you. I will try to address these points. Jehochman Talk 16:31, 18 November 2018 (UTC)[reply]

I've whacked away at all these points noted above. It is not perfect yet. Next session I will work on removing more duplicate links. Jehochman Talk 21:50, 10 December 2018 (UTC)[reply]
that table really shouldn’t be in this article. Move it to Trans-Neptunian object   User:Dunkleosteus77 |push to talk  05:07, 11 December 2018 (UTC)[reply]
Agree. We’re discussing (Agmartin and I) how to create at least one new article where to put that and some other excessive detail. Jehochman Talk 12:49, 11 December 2018 (UTC)[reply]
I've created extreme trans-Neptunian object and placed the content there that does not relate directly to Planet Nine. I think this helps streamline the article. Jehochman Talk 21:30, 11 December 2018 (UTC)[reply]
And now the duplicate links have been fixed. Jehochman Talk 20:33, 12 December 2018 (UTC)  Done[reply]

Planet X edit

I've added a section to the article's talk page about the Not to be confused with Planet X note at the beginning of the article. This note is confusing, and should probably be done differently to reflect actual usage of the term Planet X. Renerpho (talk) 06:42, 18 November 2018 (UTC)[reply]

I have reworked that. How is it now? Jehochman Talk 09:03, 22 November 2018 (UTC)  Done[reply]
Thanks! I'd be happy with it as it is now. There doesn't seem to be consensus yet whether the edit actually adds new problems, but it does solve the original problem. Renerpho (talk) 14:21, 22 November 2018 (UTC)[reply]

Image review

  • File:Planet nine path in orion2.png: suggest scaling up this image in the article
  • File:Planet_Nine_comparison.jpg: on what datasource is this based? Same with File:Planet_nine-etnos_now-new3.png, File:Planet_nine-etnos_now-close-new.png, File:Tilting_of_Laplace_Plane_by_Planet_Nine.png
  • File:Secular_evolution_of_eTNOs_induced_by_Planet_Nine.png: there seems to be a query on the image description page about claiming this as fair use? Nikkimaria (talk) 22:37, 18 November 2018 (UTC)[reply]
  • I've asked for more help with the images. The image authors are best positioned to address these points. Jehochman Talk 15:59, 10 December 2018 (UTC)  Done[reply]

Comments from Jens Lallensack edit

This is a great piece of work, and I have no concerns regarding its accuracy. However, I tried to read and had to give up after a while when I noticed I can't follow anymore. Above all, I got confused about the article structure. You start with the "five peculiarities of the Solar System" that could be explained by Planet Nine. So far so good; I have a vague idea what they mean, and where looking forward to read how Planet Nine could explain them. Then comes the heading "Observations". My first question here: Shouldn't all of the "five peculiarities" be dealt with there (and the "five peculiarities" list included within that section)? That was what I would have expected. Instead, you quickly go on with the "Trujillo and Sheppard (2014)" theory, which, as can be read further below, is an alternate hypothesis assuming a circular orbit of Planet nine. Shouldn't that be dealt with in the "Alternate hypothesis" section only? This way it is very confusing. Also, I would not discuss that hypothesis when there is absolutely no information what it actually is about (that only comes much later in the article). To understand it, you need to know that it is an alternative hypothesis assuming a circular orbit. This information is not given where it is needed. The article now apparently loses its read thread, at least in my eyes. It would be much easier to follow if the five "peculiarities" would be addressed point by point.

  • Then comes the section "Extreme trans-Neptunian objects". Seems to contain general info on these objects. But why this section in this place? Extreme trans-Neptunian objects were discussed earlier already.
  • Section "Dynamics: Effect on other objects in the Solar System" – Not sure why this is a separate section, it only seems to be based on observations or simulations (the previous two sections)? --Jens Lallensack (talk) 20:46, 21 November 2018 (UTC)[reply]
    • Fair points. Since this grew organically as discoveries were made, it needs a top down reorganization of the content into logical sections. Jehochman Talk 09:04, 22 November 2018 (UTC)[reply]
    • I'm having a friend read the article and give me ideas on better organization. It's helpful to get an outside view. Jehochman Talk 22:10, 26 November 2018 (UTC)[reply]
    • I've done a fairly major reorganization. Is the order now more logical? Jehochman Talk 15:01, 10 December 2018 (UTC)  Done[reply]
Thanks, reading again now. Looks good so far! --Jens Lallensack (talk) 08:13, 14 December 2018 (UTC)[reply]

Round Two edit

I think we've addressed nearly all of the comments above including: article organization, removal of excess detail, explanation of technical terms, removal of redundant links and picture issues. Maybe we're not perfect yet. Please let me know about remaining issues. Jehochman Talk 20:32, 12 December 2018 (UTC)[reply]

If there are no further questions, how about we promote this article? ¯\_(ツ)_/¯ Jehochman Talk 00:18, 14 December 2018 (UTC)[reply]
Wait, I barely read halfway through the Evidence section before I had to stop because I was getting nothing. I’m not well versed in astronomy and this article is still pretty hard for me to understand, so I’m worried about its readability   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
  • What’s a semi major axis?   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done[reply]
  • Could you say in numbers what the mass and diameter of the planet should be rather than saying it’s some measure bigger than Earth’s (which I don’t know)?   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done[reply]
  • I don’t understand why any of the peculiarities of the solar system are weird. Are eTNO’s supposed to have parallel orbits with the planets? What’s their semi major axis supposed to be? I don’t understand what’s going on with obliquity   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
  • The explainer in parentheses for arguments of perihelion just confuses me   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done Unfortunately, this is a complex parameter with no simple explanation. Jehochman Talk 15:03, 14 December 2018 (UTC)[reply]
  • What’s the alignment for eTNO’s supposed to be?   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done[reply]
  • I still don’t know what the Kozai mechanism is   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done - I've tried again, but no super-simple explanation exists. In science you sometimes need to learn the terminology by reading a lot of background. Jehochman Talk 15:03, 14 December 2018 (UTC)[reply]
  • ”with objects having perihelia opposite Planet Nine's perihelion, beyond 250 AU, weak alignment between 150 AU and 250 AU, and little effect inside 150 AU,” I think I’m not understanding this because there’s something wrong grammatically but I don’t know what it’s trying to say so I can’t fix it   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)  Done I've broken that down to three sentences for clarity. Jehochman Talk 15:03, 14 December 2018 (UTC)[reply]
  • At the end of the Simulations section you need a really simple and clear sentence as void as possible of astronomy jargon explaining what just happened   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
  • You need to put the Dynamics section before the Observations section because it explains why you’re even looking at eTNO’s   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
  • What’s apsidal?   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
  • You need to go over this article again and ask yourself if the average high school graduate could understand what’s going on   User:Dunkleosteus77 |push to talk  02:44, 14 December 2018 (UTC)[reply]
Well, I wouldn't be that drastic and definite. The article should ideally be useful for lay people and experts alike; and people without any pre-knowledge may be asked to follow the wikilinks for basic geometrical terms such as semi-major axis. --Jens Lallensack (talk) 08:13, 14 December 2018 (UTC)[reply]

(edit conflict)

I still go to the links and I have no idea what’s going on because they’re all written for an audience that already has a good background on astronomy, and it is good practice to explain jargon in-text regardless if it’s wikilinked or not   User:Dunkleosteus77 |push to talk  14:05, 14 December 2018 (UTC)[reply]
Agree. I've made a bunch of changes, including removal of the excessive and intimidating detail in the dynamics section to a daughter article. Those who want to know all about it can click in. Otherwise, the casual reader can consume a short summary and move on. Jehochman Talk 15:03, 14 December 2018 (UTC)[reply]

Round 3 edit

We’ve addressed all concerns above. The article is not perfect and never will be, but I think it is now very high quality. Through this process we have improved readability. It is not only complete and accurate, but reasonably accessible. Please let us know about any further concerns or whether it can be promoted now. Jehochman Talk 00:57, 15 December 2018 (UTC)[reply]

More comments from Jens Lallensack

  • ecliptic is explained, but I would move this explanation up to where the term is first mentioned.
  • Upon further analysis, Trujillo and Sheppard observed that the arguments of perihelion, the angle between where the orbit crosses the ecliptic plane and where an object makes its closes approach to the Sun, of 12 eTNOs with perihelia greater than 30 AU and semi-major axes greater than 150 AU were clustered near zero degrees. – I'm confused. The linked article "arguments of perihelion" tells us that An argument of periapsis of 0° means that the orbiting body will be at its closest approach to the central body. This means that the eTNOs are closest to the sun when they cross the ecliptic (and the orbital plane of the planet they want to avoid). How does that fit with passing "well over or under the planet"?
    (1) Trujillo and Shepherd's analysis was tainted by including objects influenced by Neptune. (2) Planet Nine is inclined. Jehochman Talk 02:52, 16 December 2018 (UTC)[reply]
  • Upon further analysis, Trujillo and Sheppard observed that the arguments of perihelion, the angle between where the orbit crosses the ecliptic plane and where an object makes its closes approach to the Sun, of 12 eTNOs with perihelia greater than 30 AU and semi-major axes greater than 150 AU were clustered near zero degrees. – Again this one; perhaps add what this means in easy words (e.g., "meaning that they cross the ecliptic when they are closest to the sun"), perhaps instead of the explanation for the term "arguments of perihelion"? Not sure.
  • so that they would pass well over or under the planet when at the same radius from the Sun – radius of what? I would have expected the word "distance" instead of radius.
  • resulting in a clustering of their longitudes of perihelion, the directions where they make their closest approaches to the Sun – why "directions", why not "locations"?
  • have argument of perihelion 0–40° – "have arguments of perihelion between 0 and 40°"? --Jens Lallensack (talk) 11:49, 15 December 2018 (UTC)[reply]
  • and sorry for asking these probably stupid questions, but I think it helps to know what a lay reader like me does not understand. --Jens Lallensack (talk) 12:08, 15 December 2018 (UTC)[reply]
Yes it does. Thank you. I will work on them. Jehochman Talk 13:55, 15 December 2018 (UTC)[reply]
  • semi-major axis scattered disk objects – that means scattered disk objects with large semi-major axes?
  • I would link and explain "scattered disk objects" at first mention.
  • same with "anti-aligned".
  • co-planar groups – link to coplanarity? Or couldn't we even find easier words for it, such as "with similar inclinations" or something?
  • sculpted into roughly collinear and co-planar groups of spatially confined orbits – Being collinear and co-planar already means they are spatially confined, right? Why then stating "spatially confined"? Are they confined in yet another way?
  • Objects beyond 250 AU semi-major axis are strongly anti-aligned – I guess, "Objects with semi-major axes beyond 250 AU are strongly …"?
  • If Planet Nine was on this orbit during the planetary instability described in the Nice model these objects would form a roughly spherical cloud centered on Planet Nine's semi-major axis with a current mass of 0.3–0.4 Earth masses, roughly 10 times that of the Kuiper belt. – I tried, but this is incomprehensible to me. Not sure what "these objects" is referring to; are you talking about the initial configuration assumed by the Nice model? How is "centered around the semi-major axis" to be understood? Maybe briefly explain "Nice model"?
    I judge this to be a non-sequitur sentence and have removed it. It's just not helping and very likely to confuse. Jehochman Talk 02:52, 16 December 2018 (UTC)[reply]
  • Other possible orbits were also examined – this paragraph lists the results of various studies. I get an idea, but I lack the background to guess what that could mean for the Planet Nine hypothesis. I mean, I was not able to get anything from this section. Perhaps add some explanation?
  • that the population captured was smaller in simulations with a planet in a circular orbit – what do you mean with "population captured"? These are simulations, one controls the population anyways?
  • Simulations have shown that the Planet Nine hypothesis successfully predicts the observed configuration of objects in the Solar System. – maybe a slight article structure problem here. This would include everything, also the tilt of the sun, which has not been discussed yet. --Jens Lallensack (talk) 20:21, 15 December 2018 (UTC)[reply]
Thank you for these detailed comments. They are very valuable for improving the article. I have addressed each one. When you have time, please check and see if the article is now easier to understand. Jehochman Talk 02:58, 16 December 2018 (UTC)[reply]

OK, did read the two sections again:

  • For similar semi-major axis objects – again, sounds like "semi-major axis object" is a term
  • This was out of alignment with how the Kozai mechanism would align these orbits, at c. 0° or 180° – but the Kozai mechanism also assumes an unknown planet? How the Kozai mechanism would align the orbits would simply depend on the orbit of that unknown planet?
  • However, Trujillo and Sheppard's theory has been supplanted by further analysis and evidence. – maybe "hypothesis" is more accurate? And what exactly has been supplanted? The idea that there is an unknown planet (but that would be Planet nine by any definition?). The existence of the Kozai mechanism? This is still not clear to me.
  • the plane of the Solar System – I would decide whether to use "ecliptic" or "plane of the Solar system", and do it consistently. Do not use different terms if you mean the same thing, as the reader assumes that different terms have different meanings.
  • I would link first appearance of the word "co-planar"
  • Investigations by Cáceres et al. showed that a planet with a lower perihelion led to a narrower confinement of orbits of the eTNOs, with a perihelion of 90 AU or higher being consistent with the distribution of the classical Kuiper belt objects. – first "lower perihelion", then higher perihelions: Somehow contradictory, so are these two alternative hypothesis, how do they relate?
  • I would link "resonance" at first mention, and maybe "orbtial resonance" a second time. --Jens Lallensack (talk) 10:22, 16 December 2018 (UTC)[reply]
 Done Thank you. Jehochman Talk 20:54, 16 December 2018 (UTC)[reply]

Round 4 edit

Please support or identify any remaining issues. Jehochman Talk 21:03, 16 December 2018 (UTC)[reply]

  • Hey Jens Lallensack, what do you think of the lead? It seems kinda small for an article of this size but I don't wanna recommend increasing it if there's really nothing much more that should be said. I haven't even read beyond the Evidence section so I wouldn't know very well if the lead's a good summary right now or not. I notice there's nothing about alternate hypotheses   User:Dunkleosteus77 |push to talk  21:31, 16 December 2018 (UTC)[reply]
The alternative hypothesis could be summarized in the lede. I'll look at that. Jehochman Talk 14:06, 17 December 2018 (UTC)[reply]
  • Are you sure quotes are the best way to go in the Reception section? I feel it reads like a news article, but then again that just might be me and my personal preferences. My brain automatically skips over anything in quotes   User:Dunkleosteus77 |push to talk  21:31, 16 December 2018 (UTC)[reply]
There section is about reactions. Rather than paraphrase and possibly alter them, it seems least risky to use quotes. Jehochman Talk 14:06, 17 December 2018 (UTC)[reply]
Naming can't happen until there's a discovery. Naming should probably be last until a name is chosen, at which point it will get merged into history. In essence, past things come first, and future things come last. I had considered placing Origin earlier, but it didn't read right. I will look again. Jehochman Talk 14:06, 17 December 2018 (UTC)[reply]
I will consider merging those. Jehochman Talk 14:06, 17 December 2018 (UTC)[reply]
I've reorganized it a bit. Please check again. Thank you. Jehochman Talk 14:17, 17 December 2018 (UTC)[reply]

Coord note edit

I realise this nom is still getting attention but after more than a month without any support for promotion, it's effectively become a Peer Review and really I think that's where it should continue, rather than at FAC, so I'm going to archive it. When the remaining points have been worked through, when Cas and perhaps others have had a change to add further commentary, it can be brought back here as a re-nom and the reviewers invited to return for another look. Cheers, Ian Rose (talk) 00:57, 22 December 2018 (UTC)[reply]

Sir, could you move this instead of disabling productive ongoing discussions? Have you ever heard there is no deadline? This is a bit of a catch 22. Questions were raised and addressed, fully as of Dec 17. Things are a bit slow this time of year due to holidays and year end business that all of us have to deal with. Jehochman Talk 03:35, 22 December 2018 (UTC)[reply]
The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.