Talk:Pluto

Odd Object Out

In the opening paragraph in the article, it is cited that [Pluto] "was always the odd object out." This statement is vague and warrants clarification. Is this in reference to its size? If so, perhaps a reference to a source pointing Pluto out as unique would be warranted. — Preceding unsigned comment added by 146.229.255.21 (talk) 20:15, 15 September 2022 (UTC)

+1, this is really weird phrasing. 68.175.116.82 (talk) 16:09, 17 September 2022 (UTC)

It was common phrasing throughout the 20th century. It's not just size, but the fact that when classifying the planets, Pluto didn't fit in anywhere (now of course it does). There were the terrestrial planets, the gas giants, and then odd Pluto at the fringes of the SS. Part of the appeal of Pluto was that it was the oddball. — kwami (talk) 19:48, 17 September 2022 (UTC)

'common phrasing throughout the 20th century' doesn't cut it. We are in the 21st century, and that wording is biased and unscientific. — Preceding unsigned comment added by 2.103.111.118 (talk) 20:29, 16 September 2023 (UTC)

Perfectly irrelevant, considering that the words in question are describing the situation in most of the 20th century. Pluto only stopped being the odd object out once some actually large TNOs started being discovered, like Varuna or Quaoar. Double sharp (talk) 12:36, 17 September 2023 (UTC)

I do agree with this claim that this phrasing should at least be modified. The sentence even works without it; you could continue with "and its planetary status" without adding that statement about being the "odd object out." TIMBITS42 (talk) 20:32, 21 February 2024 (UTC)

When Pluto was closer to the sun than Neptune

I know that Pluto was closer to the sun than Neptune between 1979 and 1999, but this also happened between 1735 and 1749 and between 1483 and 1503. But what is interesting about this is that this phenomenon also happened in the year 1AD, according to my mental orbital calculations. Is that true? Ar Colorado (talk) 15:06, 19 October 2022 (UTC)

Could be, but I don't see why that would be any more interesting than 1999. 1 AD and 1999 are fairly arbitrary dates. — kwami (talk) 04:23, 16 February 2023 (UTC)

If you subtract 8 orbital periods from the perihelion date of 1989, you get 5.5 AD. That's a consequence of Pluto's orbital period being very close to a quarter millennium, but I don't know if it was closer than Neptune for 20 years in that orbit as it was in this orbit -- and that's assuming the orbit has been stable that long, which isn't yet known. — kwami (talk) 04:32, 16 February 2023 (UTC)

Certainly known now, given that the orbits of highly eccentric asteroids can be calculated very precisely. — Preceding unsigned comment added by 2.103.111.118 (talk) 20:31, 16 September 2023 (UTC)

Semi-protected edit request on 21 April 2023

I suggest adding a reference to the contribution of Elizabeth L. Willians to the discovery of Pluto. She did the necessary calculations for Lowell to predict the location, and in fact her calculations and predictions based on them led to Lowell capturing an image of Pluto in 1915, which went unnoticed. Eventually, finding Pluto by Clyde Tombaugh indeed relied on the work she did. Multiple references exist in Elizabeth's Wikipedia page: https://en.wikipedia.org/wiki/Elizabeth_Langdon_Williams and also in other sources, such as https://www.space.com/human-computer-elizabeth-williams-pluto-discovery.html (see more sources within).

Please change: Lowell and his observatory conducted his search until his death in 1916, but to no avail. Unknown to Lowell, his surveys had captured two faint images of Pluto on March 19 and April 7, 1915, but they were not recognized for what they were.

to: Lowell and his observatory conducted his search, based on the mathematical calculations made by Elizabeth L. Williams, until his death in 1916, but to no avail. Unknown to Lowell, his surveys had captured two faint images of Pluto on March 19 and April 7, 1915, but they were not recognized for what they were.

77.127.190.148 (talk) 05:26, 21 April 2023 (UTC)

Done, with a link. — kwami (talk) 22:32, 21 April 2023 (UTC)

Semi-protected edit request on 9 May 2023

More of a suggestion than a request, but I think the "Quasi-satillite" subsection should be moved from the "Orbit" header to the "Satellites" header. I know why it's currently under Orbit, but I think it'd make sense under Satellites as well. 47.20.182.16 (talk) 12:57, 9 May 2023 (UTC)

agree, it makes more sense. moved. Artem.G (talk) 16:15, 9 May 2023 (UTC)

"Pluto." listed at Redirects for discussion

The redirect Pluto. has been listed at redirects for discussion to determine whether its use and function meets the redirect guidelines. Readers of this page are welcome to comment on this redirect at Wikipedia:Redirects for discussion/Log/2023 November 6 § Pluto. until a consensus is reached. Gonnym (talk) 12:18, 6 November 2023 (UTC)

Add "Trans-Neptunian object" link

to: https://en.wikipedia.org/wiki/Trans-Neptunian_object Sisu-agape (talk) 07:45, 29 November 2023 (UTC)

It's already in the lede. Click on "bodies beyond the orbit of Neptune". Double sharp (talk) 09:06, 29 November 2023 (UTC)

Pluto's Northern Hemisphere should be Southern Hemisphere?

Pluto rotates by 122.53° from the Plutonian ecliptic plane, meaning Pluto is "upside down" and rotates backward relative to 6/8 of our major planets.

According to NASA's "Eyes in the Solar System" planet viewer, this would make the "Heart of Pluto" actually "upside down" compared to the 6 major planets and the orbital directions of all planets. Do you think we should change the caption of the main photo from Northern Hemisphere to Southern Hemisphere. IapetusCallistus (talk) 12:01, 21 January 2024 (UTC)

Per Axial tilt#Standards, the standard is to say that the north pole is the one on Earth's north side of the invariable plane. Everyone's using it, so let's stick to it. (In IAU terminology, what's going on is just that the positive pole of Pluto is its south pole, whereas the positive pole of Earth is its north pole.) Double sharp (talk) 13:20, 21 January 2024 (UTC)

Wouldn't that mean Pluto's rotation is retrograde? We seem to be somewhat inconsistent in our usage. — kwami (talk) 20:50, 21 January 2024 (UTC)

I suppose so, since its tilt is >90°. Double sharp (talk) 03:59, 22 January 2024 (UTC)

is Pluto still considered a planet?

???? 71.212.121.60 (talk) 19:58, 7 February 2024 (UTC)

Depends on your definition of "planet". Our planet article covers the issue. — kwami (talk) 00:03, 8 February 2024 (UTC)

Mass and Size

"On July 13, 2015, images from NASA's New Horizons mission Long Range Reconnaissance Imager (LORRI), along with data from the other instruments, determined Pluto's diameter to be 2,370 km (1,470 mi), which was later revised to be 2,372 km (1,474 mi) on July 24, and later to 2374±8 km."

Unfortunately, 2370 km is (1472.6 mi), not (1470 mi). It really jumps out because the next diameter given is only 2 km more than 2370 km but the conversion jumps up by 4 miles. I didn't change anything because I didn't have time to go through all the source material to see if the mistake is on the Wikipedia page or in the source material. But if someone does have time, please have at it. 2600:1002:B039:3FA9:CD58:FAE6:35C1:3C6C (talk) 06:23, 21 February 2024 (UTC)

I was originally going to comment that this was probably a matter of significant figures. But then I noticed that the source gives Charon to single-kilometer precision, so presumably Pluto also was and just had the bad luck to end in 0. So, corrected to 1473 mi according to the source. Double sharp (talk) 06:36, 21 February 2024 (UTC)

Suggestion for hyperlink

Hello, new user here. In the first paragraph of this article, the term "Trans-Neptunian object" is used to describe Pluto. As someone who was unfamiliar with the term, I went and found information about what that is on another page here on Wikipedia. I think it would bring clarity to link that page explaining what a trans-Neptunian object is. K74HM86 (talk) 21:28, 21 February 2024 (UTC)

@K74HM86 Thanks for the suggestion. We currently have a link to that article for the phrase "bodies beyond the orbit of Neptune". I do think linking trans-neptunian object would be effective in removing confusion but am unsure how we should approach it given the previously mentioned link. —Panamitsu (talk) 21:46, 21 February 2024 (UTC)

The rotation period is wrong

The time it takes for Pluto to complete one full rotation is 6.387 days and not 6.386 days. OrangeAedan (talk) 14:41, 22 March 2024 (UTC)

The article does say 6.387 days. Double sharp (talk) 16:49, 22 March 2024 (UTC)

It says 6.386. Look: [[Pluto#:~:text=Synodic rotation period,[8]]] OrangeAedan (talk) 17:25, 23 March 2024 (UTC)

You're looking at the synodic rotation period, which is different from the sidereal rotation period. ArkHyena (talk) 21:28, 23 March 2024 (UTC)