Talk:Neptune/Archive 3

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Thanks

This featured article was helpful in my research, this is how more articles here should be done.VisioNaryD (talk) 04:33, 17 January 2009 (UTC)

Unit Disagreement

There seems to be an ongoing disagreement about whether to use British-English or American-English in the article. I believe the policy is to stick to the original form the article was written in and to be consistent within the article. PhySusie (talk) 11:43, 5 July 2008 (UTC)

Here is a link to the Wikipedia policy Wikipedia:Manual of Style PhySusie (talk) 11:47, 5 July 2008 (UTC)

The original form was American English. It was later switched to British English, per a very weak consensus. It was my misunderstanding, and it has been properly reverted back to British English. (There really ought to be a comment at the top of the edit page to let you know.)—RJH (talk)

There is no evidence whatsoever of any consensus here on the talk page, not even a "very weak" one. If the original form was American English, it would not be "properly reverted back to British English". Gene Nygaard (talk) 04:03, 13 January 2009 (UTC)

Great Dark Spot

Do you know Great Dark Spot is not a permanent storm? See commons:Category:Neptune (atmosphere), sometimes the great dark spot wears outwhen the disc is greener, most often the disc is rich blue.--Freewayguy ^{What's up?} 23:38, 22 August 2008 (UTC)

The lifetime of Dark Spots is only a few years. Since 70-th several such spots appeared/disappeared in southern and northern hemispheres. Ruslik (talk) 08:43, 23 August 2008 (UTC)

Discovery section POV

Hi, I think the current version of the Discovery section is a bit POV because there is only one image, and that is of Urbain Le Verrier. I will propose to add one image of Adams (who co-discovered the existence and position of the planet) and one image of Galle who was the first to knowingly observe it, thus confirming its existence. Since the credit of the discovery belongs to three persons, two other images are also necessary. Otolemur crassicaudatus (talk) 17:30, 10 December 2008 (UTC)

Adams's role in the discovery of Neptune has been overplayed. We now know that Adams's predictions were very wide of the mark, and that LeVerrier really deserves sole credit. All??? Galle and D'Arrest did was confirm LeVerrier's prediction. Serendi^podous 17:32, 10 December 2008 (UTC)

Th dark spot on Neptune is really a storm. It will never go away, no matter how much you want it to. —Preceding unsigned comment added by Zachattack966 (talk • contribs) 15:10, 12 February 2009 (UTC)

Neptune#Atmosphere

I've wikilinked "gravity wave" to Gravity wave. Is this right, or should it be Gravitational wave? --Milkbreath (talk) 13:57, 12 January 2009 (UTC)

Gravity wave is not the same as gravitational wave. In this case it is gravity wave. Ruslik (talk) 14:48, 12 January 2009 (UTC)

Neptune#Climate

I'm tempted to put an extra set of quotation marks around "skin effect" just to be sure. What's that supposed to mean? --Milkbreath (talk) 15:24, 12 January 2009 (UTC)

It looks like the authors meant "surface effect", but the word surface is ambiguous for a gas giant. Skin effect implies a thin outer section of the entire planet, as indicated by the succeeding text in that sentence. But having double quotes there is probably a good idea.—RJH (talk) 18:05, 12 January 2009 (UTC)

Regarding your other mass edits to the article, you may have introduced some serial commas. Please be careful that the article does not stray from the wikipedia style guidelines.—RJH (talk) 22:31, 12 January 2009 (UTC)

Without even looking first, I'm going to claim that the guidelines say to stick with the style prevalent in an article as you find it. I do try to do that, and if I did put in such commas, it was in the belief that I was enhancing the consistency of the page. In fact, when I looked it over a second time, I saw one missing in the lead. Feel free to go through the article and set it to "serial" or "no serial" as you see fit. It's a matter of complete indifference to me unless it creates an ambiguity or lends a false meaning. And I don't do "mass edits". Are you a journalist? I edit the entire article, and this one needed it.

Nope I'm not a journalist, but I do take note of reviewer complains during the FAC process and try to take them into consideration. Serial commas is one such issue, and there are a couple more that I found in your edits; some will undoubtedly be fixed by periodic bots that sweep through these pages. =) The page has been reviewed on multiple instances by experienced reviewers, but there is always room for improvement. Entropy is also a factor in maintaining these pages; minor edit changes can introduce inconsistencies and peculiarities. Thanks.—RJH (talk) 18:31, 13 January 2009 (UTC)

What???! There are comma bots? Give me their names so I can go kick their asses. Seriously, a bot can't decide whether to use a comma or not. Very few humans can, and none of them are programmers. As for creep or entropy or whatever, I know what I'm doing. I kill inconsistencies and peculiarities the instant I find them. I kill them with extreme prejudice. I am the champion of the people, at least of the people who just want to read in peace. So, let me ask you, which way do you want to see it, serial comma or no serial comma? I'll go through and make them all the same at your whim, just to be Wikinice. --Milkbreath (talk) 18:59, 13 January 2009 (UTC)

Sheesh. There's a saying in the computing biz: "Be nice, or I'll replace you with a very small shell script." Anyway, I dealt with the issue. ;-) Thanks.—RJH (talk) 17:37, 8 February 2009 (UTC)

So, what the heck is "skin effect"? Nobody seems to know, exactly, and when Wikilinked it goes, of course, to the electronics one. A search of Wikipedia yields nothing, too. --Milkbreath (talk) 23:52, 12 January 2009 (UTC)

There is only little difference between "skin effect" on Neptune and one in electronics. "Skin effect" means that something happens just in a thin outer layer of a planet (in the atmosphere, for instance) or in a thin layer near the surface of a conductor in electronics. Ruslik (talk) 19:26, 13 January 2009 (UTC)

Dubious

"The magnetic field at the equatorial surface of Neptune is estimated at 1.42 μT, for a magnetic moment of 2.16×10¹⁷ Tm³."

Please provide, if possible, a citation for both that specific number "2.16×10¹⁷ Tm³" and for its characterization as the "magnetic moment".

This is dubious for several reasons

1. The units of "magnetic moment" are not cubic terameters
   1. There are two ways in which magnetic moment is expressed in SI, both mentioned in the article linked to in that extract: joules per tesla, or the equivalent in terms of the base units, ampere-square meters. The dimensions of "magnetic moment" are not L³, but rather I·L²
   2. It is a bad choice of prefixes; 2.16×10¹⁷ Tm³ would be better expressed as 0.216 Em³ or 2.16×10⁻¹ Em³ or 2.16×10⁸ Pm³ or best, simply 2.16×10⁵³ m³.
2. But this number wouldn't be square terameters in any case. It is actually 10r³μ, where r is the equatorial radius of Neptune (24,760,000 m) and μ is 0.00000142 T.
   1. So what was intended wasn't really 2.16×10¹⁷ Tm³, , but rather 2.16×10¹⁷ T·m³, which has entirely different units, teslas times cubic meters.
   2. The factor of 10 is likely spurious, an calculation error that is just a mis-placement of the decimal point somewhere in the calculations.
      1. If it wasn't spurious, is it a dimensionless number, or some other quantity not necessarily exactly 10 which has dimensions?
   3. That doesn't have dimensions of magnetic moment, either; it has dimensions of M·L³·T·I⁻¹

I'm wondering if this xr³μ quantity is meaningful, if it is generally measured in this context.

• If so, what it it normally called?

If someone knows the answers to that, and if it is in fact called magnetic moment, then whoever knows about this might consider editing magnetic moment appropriately. If such edits run into resistance, however, we'd need to look at it again. Gene Nygaard (talk) 00:14, 13 January 2009 (UTC)

Magnetic field is actually 14.2 μT, and magnetic moment is measured in Tesla•cubic meter, of course (not terameters). The later unit is quite common in planetary sciences. Ruslik (talk) 10:38, 13 January 2009 (UTC)

Well, let's see

1. some evidence that it is used outside Wikipedia,
2. the evidence to support your willy-nilly change of the first number (that number is now in the dubious class too),
3. a reference for the number given here, and
4. any evidence for what this quantity is properly called (like I said above, and like our Wikipedia article says, and every other source I find, magnetic moment is measured in "J/T" or in "A·m²", not in "Tm³" and not in "T·m³" either).

Note further that teslas start with a lowercase T like the names of all units, that it is improper to use a bullet as a mathematical operator between between spelled out words, and that the problem isn't in spelled-out words in the first place, but rather in the failure to use proper symbols separated by either a middot or a hard space (T·m³ or T m³). Gene Nygaard (talk) 13:38, 13 January 2009 (UTC)

As near as I can figure out, it looks like the calculations of magnetic moment should be using H (measured in units such as amperes per meter) rather than B (measured in units such as teslas). See magnetic field. They are related as follows:

$\mathbf {B} =\mu _{0}(\mathbf {H} +\mathbf {M} )$ (SI units)

$\mathbf {B} =\mathbf {H} +4\pi \mathbf {M}$ (cgs units),

where M is magnetization density of any magnetic material.

Using a field measured in amperes per meter (A/m), then multiplying it by the cube of the radius (m³), gives you the units of A·m² of magnetic moment. Gene Nygaard (talk) 15:15, 13 January 2009 (UTC)

There is a typo in Russell (ref 52). Russell actually uses information from Connerney, et.al 1991, where the dipole magnetic field is 0.14 G=14 μT. Magnetic moment (dipole moment) in Connerney is listed as 0.14 G R_N³, which can be easily converted to T m³. And Connerney is the most widely cited publication about magnetic field of Neptune.

And my change was not willy-nilly. Ruslik (talk) 17:05, 13 January 2009 (UTC)

You still haven't addressed why this is something different from the normal magnetic moment which is measured in joules per tesla or in ampere-square meters. Gene Nygaard (talk) 01:55, 17 January 2009 (UTC)

It is different because planetary scientists do not like SI units. Ruslik (talk) 09:42, 17 January 2009 (UTC)

Hubble image?

I believe all the photos in this article are from Voyager 2. Could the best image from Hubble Space Telescope be included? [1] is an example; and perhaps the best image that can be found that has ever been taken from an Earth telescope. I think a visual comparison would nicely illustrate the difficulties in observing Neptune from Earth. Tempshill (talk) 06:13, 17 January 2009 (UTC)

• [2] was Astronomy Picture of the Day in 2000, a Keck image using adaptive optics. I'm not at all sure if it's a NASA image, and don't know the rights situation. Tempshill (talk) 06:33, 17 January 2009 (UTC)

Congratulations!

Congrats to featurization, fellow astro-geeks. ... said: Rursus (bork²) 10:23, 17 January 2009 (UTC)

Dark Matter

A recent hypothesis posits that Neptune's and the other Jovian planets' internal heat is caused by interaction between the planet and a gravitationally bound dark matter cloud, which the planets are enveloped in. In this picture, the heat is derived from occasional scattering of dark matter WIMPs off atoms within the planets' interior, or from the self-annihilation of dark matter within the planet, provided the cross-section between dark matter and normal matter is low enough. All of the planets, including the Earth, would be then internally heated by this process. Uranus's anamalously low heat output could have been the result of the collision that knocked the planet to its present highly inclined axial tilt, which may have also knocked Uranus free of its associated dark matter cloud.(Adler 2008) -- 13:09, 2 June 2009 (UTC)

It's an interesting idea, but I'm not sure it is sufficiently well established to be covered anywhere except on the dark matter page.—RJH (talk) 16:07, 2 June 2009 (UTC)

I think I agree. (I have not read the reference). But I do think it should be kept somewhere that is why I moved it to the talk page so that it could be archived somewhere. We really don't know what processes heat the interior of the giant planets. -- Kheider (talk) 16:24, 2 June 2009 (UTC)

I don't see why this was removed from the main article. This hypothesis is just as good as a potential explanation to the Jovian planets' internal heat generation as any of the others in the article, particularly since they all rely on equally untested assumptions.JayMan (talk) 16:00, 4 June 2009 (UTC)

The big problem (for me at least) is that there is simply no evidence for dark matter at anything below galactic level, and since we don't even know if dark matter exists yet, I think it's a bit premature to start invoking it at the level of the Solar System. Serendi^podous 16:11, 4 June 2009 (UTC)

A suggestion would be to add a paragraph to the Planetary core article, then link that to the 'See also' section of this page. If the conjecture gains more credence and some sort of experimental evidence pertaining to Neptune, then we can always add it back in here.—RJH (talk) 18:33, 4 June 2009 (UTC)

None can be singular or plural

This edit changed "were" to "was" in "...though none of the planet's remaining 12 moons was located...". Being in the mood for a grammar war, I thought I would mention englishplus and reference and randomhouse as just three sources that support "none was" and "none were", depending on context. Accordingly, I plan to restore "were" but thought I'd get opinions first (don't really want a war). Johnuniq (talk) 04:50, 13 June 2009 (UTC)

I hate grammar geekery, but I thought I'd contribute this bit of pedantry by the luvverly Stephen Fry. Serendi^podous 05:20, 13 June 2009 (UTC)

Well I'm no grammar expert, but "were" does read better in this instance. Thanks.—RJH (talk) 16:46, 28 June 2009 (UTC)

Galileo

If Galileo didn't know what he was looking at, how can *we* claim that he discovered it? Even Galileo may not have considered the idea of large planets beyond Saturn being found so easily. To Galileo it was probably just a star that he may have simply miss plotted on his earlier charts. This is just a precovery sighting of Neptune. -- Kheider (talk) 17:59, 10 July 2009 (UTC)

Not necessarily Serendi^podous 18:03, 10 July 2009 (UTC)

Galileo was looking for secondary planets (moons). Galileo had no idea what he was looking at since he was surely suffering from information overload: Planets going around the Sun (phases of Venus), planets going around planets (the 4 Galilean moons), fixed moons (rings) around Saturn, etc. I don't think it can be proven that he thought it was a more distant primary planet orbiting the Sun. Knowing (suspecting?) that a star moved does not mean that he knew what it was or even gave it much thought given everything else he was busy studying. He did not follow up on it. -- Kheider (talk) 19:16, 10 July 2009 (UTC)

I reworded it to more accurately reflect the sources. Serendi^podous 19:26, 10 July 2009 (UTC)

Good update. Thanks.—RJH (talk) 20:22, 10 July 2009 (UTC)

Does it have a surface ?

Does Neptune have a surface - in the sense that Earth, Mars, Venus and Mercury have a surface ? Or is it (along with Uranus, Saturn and Jupiter), just a ball of gases ? No one ever these important layman questions. And if it has no surface, then how can a ball of gas be a planet ? If you can't land on it then it's no different to a cloud. —Preceding unsigned comment added by 116.25.180.26 (talk) 08:17, 2 August 2009 (UTC)

It could be that scientists don't yet know, and/or there is no well-defined solid surface.—RJH (talk) 22:22, 6 August 2009 (UTC)

Surface gravity

What defines the unknown surface of a gas giant? The top of the clouds? According to Saturn: Facts & Figures the surface seems to be defined as the cloud tops. Does this fact add value to the article? -- Kheider (talk) 16:50, 11 August 2009 (UTC)

I think the "surface" is either based on the altitude where the pressure is at the 1000 millibar point or at a certain level of opacity along the horizon.—RJH (talk) 19:33, 11 August 2009 (UTC)

The "surface" of all giant planets is defined as 1 bar pressure level. Ruslik_Zero 19:36, 11 August 2009 (UTC)

Moons

According to the following NASA webpage (http://nssdc.gsfc.nasa.gov/planetary/factsheet/neptuniansatfact.html) the last five discovered moons of Neptune, discovered in 2002/2003, are named:

Name (temp name)

Halimede (NIX, S/2002 N1) Sao (NXI, S/2002 N2) Laomedeia (NXII, S/2002 N3) Psamathe (NX, S/2003 N1) Neso (NXIII, S/2002 N4) —Preceding unsigned comment added by WAAtkins (talk • contribs) 19:22, 6 August 2009 (UTC)

Discoverers

I'm not debating Adams now, but if he is listed for his effort, then why is only Johann Galle and not Heinrich Louis d'Arrest listed in the discovery list? He also partook in the search AFAIK. ... said: Rursus (^mbork³) 09:48, 23 September 2009 (UTC)

And if I defined a list, the discoverers should be Galle and d'Arrest, while Adams and Le Verrier were computers preparing for the discovery. ... said: Rursus (^mbork³) 09:50, 23 September 2009 (UTC)

That depends how you define "discovery". Galle was not doing what Clyde Tombaugh did, manually searching the entire zodiac until he stumbled across something that moved. He simply pointed his telescope where Le Verrier told him to, and confirmed what Le Verrier had already calculated. If physical observation alone is the same as discovery, then Galileo deserves credit for discovering Neptune as well. d'Arrest didn't observe Neptune. All he did was confirm that Neptune was not on the star chart. Serendi^podous 10:33, 23 September 2009 (UTC)

I define "discovery" as discovery, the literal meaning. The first to detect/reveal/affirm. I think your description is not quite accurate, AFAIK, Galle was searching a restricted area, comparing it with a star map that they, Galle and d'Arrest had available, and that d'Arrest pointed out was there. But this is of very little import, since computing the position of a never-seen planet, and making it fairly right, is no less honorable than discovering it. By tradition a "discovery" means providing measures to finding a planet or literally finding it, as a "honorable deed", but I'm just erecting a new "honorable deed" by pinpointing that preparative computing was important in this case. ... said: Rursus (^mbork³) 12:04, 23 September 2009 (UTC)

And how did Le Verrier not "provide measures to find the planet"? His calculations detected Neptune. All Galle did was confirm his calculations were correct. His "search" lasted less than half an hour. If you take your argument to its logical conclusion, then no extrasolar planet discovered via radial velocity can be counted as a discovery, because detection by gravitational perturbations doesn't count. Serendi^podous 12:11, 23 September 2009 (UTC)

First to suggest a perturbing planet

I haven't been able to run down a source for this statement:

Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesize that an unknown body was perturbing the orbit through gravitational interaction.

Sources credit him with the discovery of the discrepancies in the orbit of Uranus. However, the credit for the idea that the differences may be caused by an unknown perturbing body usually goes to Reverend Dr. T.J. Hussey of Hayes, who on November 17, 1834 wrote a letter to the Director of the Cambridge Observatory, Airy, suggesting the idea.[3]

Can this be confirmed and/or clarified? Thanks.—RJH (talk) 17:27, 26 October 2009 (UTC)

Never mind, I found a suitable reference.—RJH (talk) 18:06, 26 October 2009 (UTC)

Naked-eye visibility of Neptune

As I pointed out here, it is puzzling why no one has ever seen Neptune with the naked-eye. It should be a borderline naked-eye object. Count Iblis (talk) 16:20, 12 December 2009 (UTC)

Also keep in mind that Neptune would require (4) important things: Perfectly dark skies (Bortle Dark-Sky Scale class 1), some of the best eyes in the world, proper experience using averted vision, and Neptune would need to be at opposition so that it would be at maximum brightness. -- Kheider (talk) 17:24, 12 December 2009 (UTC)

Neptune orbit Eccentricity

The Eccentricity of Neptune's orbit according to JPL data for epoch 2000 was 0.00895439, not 0.011214269 as indicated in the Wikipedia article. The error (125%) is significant. Verification: JPL Keplerian Elements page http://ssd.jpl.nasa.gov/?planet_pos and, in particular, "Keplerian elements for 3000 BC to 3000 AD" at the bottom of that page, as well as Heavens-Above.com http://www.heavens-above.com/neptune.asp, and other on-line ephemeris pages. In addition, the value of "Argument of of Perihelion" should be -85.10477129 or +274.8952287 instead of the indicated value 265.646853. Larry McNish, Calgary Centre of the Royal Astronomical Society of Canada. 68.144.133.105 (talk) 14:15, 17 December 2009 (UTC)

NASA's Neptune factsheet gives 0.0113, while its Solar System Exploration factsheet gives 0.00859. Looks like they can't agree with themselves. Wouldn't be the first time. But, given that JPL has to know the precise orbital data for each planet or their missions can't work, I'd side with them. Serendi^podous 15:36, 17 December 2009 (UTC)

The NASA factsheet actually lists both 0.0113 and 0.00858587 for the orbital eccentricity.—RJH (talk) 17:29, 17 December 2009 (UTC)

Solex 10 shows Neptune with an instant eccentricity of 0.0112 for 2000-01-01. The 0.00858 is a long-term mean number. -- Kheider (talk) 19:48, 17 December 2009 (UTC)

Ah okay. In that case perhaps the {{infobox planet}} template documentation needs to indicate the appropriate (or preferred) value to use.—RJH (talk) 20:23, 17 December 2009 (UTC)

Keep in mind that with asteroids it is much easier to get instant Epoch values than a mean value. -- Kheider (talk) 21:05, 17 December 2009 (UTC)

No reason minor planets can't use a different criteria. Or we could just list both values in this article's infobox and label them accordingly.—RJH (talk) 22:40, 17 December 2009 (UTC)

I have re-worked Orbital_eccentricity#Examples to better explain some of this. -- Kheider (talk) 05:05, 18 December 2009 (UTC)

Neptune

The statement "Discovered on September 23, 1846,[1] Neptune was the only planet found by mathematical prediction rather than by empirical observation." is misleading. It may be more accurate to say that "Discovered on September 23, 1846,[1] Neptune was the first planet to be found by mathematical prediction rather than by empirical observation." In the last ten years or so many planets have been found outside our solar system by mathematical prediction .

Good point. Serendi^podous 15:42, 6 March 2009 (UTC)

Wouldn't "the only solar planet found" make more sense, I actually found the new wording more confusing. As in this article I'd take planet to mean a solar planet unless otherwise specified or obvious from context. 82.132.136.201 (talk) 20:47, 13 March 2010 (UTC)

Good counter point. Is the average reader going to assume "only planet found" to mean "only planet found, including extrasolar planets"; or is it more likely the average reader is going to assume "first planet found" to mean there were other solar planets discovered by this method? I propose reverting back to "only planet found..." In this context most readers, I believe, will safely assume this to mean "only solar planet found...".Racerx11 (talk) 22:20, 3 August 2010 (UTC)

Naming Section

Umm.. "The demand for a mythological name seemed to be in keeping with the nomenclature of the other planets, all of which, except for Earth, were named for Roman deities.[33]"

Isn't Uranus a greek deity not a roman one? —Preceding unsigned comment added by 69.63.50.213 (talk) 10:04, 6 March 2009 (UTC)

Well spotted! :-0) Serendi^podous 10:33, 6 March 2009 (UTC)

What is the Roman name for Uranus? --116.14.26.124 (talk) 03:50, 27 June 2009 (UTC)

Ah, I just found out. It's Caelus. --116.14.26.124 (talk) 05:30, 30 June 2009 (UTC)

Shouldn't the naming section include a brief mention that "Neptune" was chosen (and Oceanus proposed) due to the planet's blue colour? Glaurung quena (talk) 01:28, 19 January 2010 (UTC)

Yes I think it would, but a reliable source is needed.—RJH (talk) 17:10, 15 March 2010 (UTC)

Earth also has a name derived from classical mythology, although it is rarely used in common parlance: Gaia, the wife of Uranus (Ouranos).82.176.209.52 (talk) 06:14, 4 January 2011 (UTC)

Hebrew Name?

Why was the sentence about a Hebrew name thrown in as an afterthought in the English Language Wikipedia? I'm sure other countries have given Neptune their own names in their own languages but Israel played no part in the discovery of this planet. Do we need to add the lines that Neptune is called Haiwangxing in Mandarin, ket in Thai and the Greeks stubbornly call it Poseidon? . 97.85.185.160 (talk) 08:37, 8 April 2010 (UTC)

Odd. The planet's Chinese/Japanese/Korean name should be mentioned. It is for every other non-classical planet. I believe it's "sea king star" or "water king star". Serendi^podous 09:06, 8 April 2010 (UTC)

Added. I know this site's aversion to nineplanets.org, but given the nature of the fact being sited, I don't think it's an issue here. Serendi^podous 09:20, 8 April 2010 (UTC)

The Chinese/Japanese/Korean name makes some sense in the cultural/mythological context for the classical planets. I'm not so clear they are appropriate for more recent discoveries like Neptune. In the latter case it's just a name translation and would appear to provide no other value.—RJH (talk) 14:59, 8 April 2010 (UTC)

The site you just used has the line: Hebrew Shemesh Kochav Chama Nogah Eretz Yareach Ma'adim Tzedek Shabtay Uranus Neptune Pluto. So in Hebrew it is still 'Neptune'! Why have the added WP:Cruft of it's various names added in as afterthought to a paragraph focused on it's original naming and discovery? Just remove the whole line. If any of the relevant personalities were Jewish and it was documented as important to their faith; I could see the inclusion but it more belongs in a trivia section. 97.85.185.160 (talk) 10:43, 8 April 2010 (UTC)

Obviously that page hasn't been updated since before 2009. The fact that the planet has a Hebrew name is worth noting, I think, as much as its Chinese name is. And Uranus and Pluto both have their Chinese names listed. Pluto even has its Gujerati name listed. Serendi^podous 11:03, 8 April 2010 (UTC)

I disagree about the notability of adding a name from another language to a English article in the section about the original naming of the planet. What happens on other articles or other websites isn't really relevant to this page. The paragraph in mention is all about the original discovery and naming not later naming. Alatari (talk) 12:25, 8 April 2010 (UTC)

Why do you feel it is not notable? Why should this article be Anglo-centric, just because it's in English? Serendi^podous 12:35, 8 April 2010 (UTC)

This planet was unknown till modern times and these names are popular namings in 2009 by non-science sources. This is a first rate, front page featured article and those lines read as afterthoughts and are completely unrelated to the discovery and naming of the planet. You start adding each individual countries choices to not use the Anglo name then you open up the article to a crufty laundry list trivia section. The other older planet articles were written from history and the other new planets articles have had the same crufty looking lines added. The sources cited are not reliable science sources. If we add in the choice of name from Israel then we need to start adding the name (in their native script) from India, Bhutan, Indonesia, Iran, Russia and whoever else want's to not go with the English version. If you can point out a scientific journal of international renown catering to the various other names then I'll remove my objection. Otherwise I'm sticking with a deletionist-cruft-protectionist stance. Alatari (talk) 13:42, 8 April 2010 (UTC)

I have to agree. Non-English names make sense when they are relevant to mythological beliefs, provide an etymology or have some other cultural significance. Otherwise it's just serving as a translation dictionary, and we all know that Wikipedia:Wikipedia is not a dictionary. :-) —RJH (talk) 15:02, 8 April 2010 (UTC)

So are we to remove those names from the Uranus and Pluto articles as well? Seems like a pointless loss of information. Serendi^podous 17:29, 8 April 2010 (UTC)

Yeah, this is kind of a nit-picker. But if the names are not solidly referenced, then it's another argument for their removal.—RJH (talk) 19:16, 8 April 2010 (UTC)

It is poor style to just throw that sentence in at the end of a history of the planets naming. It looks like an afterthought or maybe wiki vandalism when I find a single tossed in fact with no transition. If there is a cultural jealousy of the Europeans getting the sole rights to name Neptune and Uranus then that is notable and would be an excellent angle to include this information with. For years we were supposed to believe that Columbus found the new land first but we find out now that Scandinavians had made their way there. The land bridge was supposed to be the sole way humans entered the Americas but now we find that people made their way in boats along the Atlantic ice pack. It seems possible that Neptune or Uranus had some name in some ancient culture as a roaming star and that would make a notable addition here. Whatever I just don't want to see a growing list of all the cultures that decide to use other names for Neptune/Uranus added her for like was said above Wikipedia:Wikipedia is not a dictionary. And please, please if you're going to take the time to include the Hebrew script for the name then be respectful of the Asian cultures and use their scripts in the sentence. Alatari (talk) 07:21, 15 April 2010 (UTC)

I removed it, though I still think the removal was unnecessary. No one has yet complained that Uranus and Pluto have their alternate Asian names included. I don't see why this issue is so controversial. Isn't it good enough that the information fills a hole in people's knowledge- what do cultures with no ties to Neptune the sea god call the eighth planet? Seems like information worth knowing to me. Serendi^podous 09:25, 15 April 2010 (UTC)

I agree that this is information that should be included, for the reason you've given: it provides insight into cultures with no ties to Neptune as a sea god. Please add it back. --Gyrobo (talk) 14:58, 15 April 2010 (UTC)

As long as its not just listed as the non-English equivalent name and provides some tidbit of cultural interest (such as the meaning or etymology of the name), it's probably of some value to the article.—RJH (talk) 15:08, 15 April 2010 (UTC)

I restored the Sinospheric name, in keeping with the other articles.

At first I was in favor of retaining the Hebrew as well, but then I noticed that Hebrew WP is still at "Neptune". There are all sorts of proposals for what to call things; that doesn't mean they're notable. I do think it's interesting that other languages may substitute a native equivalent for Neptune; Greek does that with Poseidon. But other than Chinese et al., everyone else appears to be just borrowing the name Neptune, even in India, though it's a bit distorted in Celtic. But this is worth exploring further: Although Bengali just calls it "Neptune", in Hindi WP the article is listed at Varuna, though in the article itself (which is just a stub) it's "Neptune" again. I have no idea how relevant that is. But in Chinese, Japanese, Korean, etc, the sinospheric name is the only one that's current, and is not in competition with the Latin name. kwami (talk) 18:11, 15 April 2010 (UTC)

Maybe we need a vote to obtain consensus. There is a larger issue here. I believe that having a list of names of any important object in different languages is part of the human knowledge of that object, and as such belongs in an encyclopedia, at least for some selected set of important objects.

To me, that information is not trivia and not just dross relevant to a few readers (fancruft). It may be relevant that we currently have kid's bilingual cartoons in Mandarin and Spanish on TV. Languages are as valuable as astronomy to a rounded education.

For example, a child doing research in elementary school could find her imagination and desire to learn stimulated by exposure to concrete examples of many languages for a thing about which she is learning. Creating links between separate fields of study can literally add a new dimension to education.

That will almost never happen in school, so it is a potentially valuable contribution by her online encyclopedia. Within limits, a multidisciplinary approach to education (in the old pedagogical meaning) makes good sense.

David Spector (talk) 13:43, 1 June 2010 (UTC)

The issue you are raising is more general than the topic of the planet Neptune, so I think it should have a broader perspective and a wider discussion. If you are going to include a few language translations, then by extension you need to include every language for comprehensiveness. You will also need pronunciation information, etymology for each language and so forth. Personally I'm against such a significant expansion of scope. That's what the wiktionary is for.—RJH (talk) 15:41, 1 June 2010 (UTC)

Related

The chemical element Neptunium, discovered by Edwin McMillan and Philip H. Abelson in 1940, was named after the planet Neptune. In the periodic table of the elements it lies between Uranium and Plutonium, which were named after Uranus and Pluto respectively.<ref name="pr57">{{cite journal | title=Radioactive Element 93 | year=1940| author=Mcmillan, Edwin | journal=Physical Review | volume=57 | page=1185 | doi=10.1103/PhysRev.57.1185.2 }}</ref>

—RJH (talk) 21:03, 20 April 2010 (UTC)

Where did this line come from? This article or Neptunium? Alatari (talk) 06:10, 14 May 2010 (UTC)

I'm not sure where to put it. There isn't an "in culture" section and given the fight we've had over the additional names, I'm a bit wary of adding it to the name section. Serendi^podous 18:22, 21 April 2010 (UTC)

The elements being named in conjunction with the planet was already in the articles last I looked. Maybe it's missing from this one? It's notable that scientists decided to name new elements after the planets since that's how the elements got their names. Alatari (talk) 19:01, 21 April 2010 (UTC)

Don't get me wrong; I want this to be included. Problem is that I've got into various fights over their inclusion, similar to the one above. I had to find an additional historical reference to include Uranium, and Plutonium only snuck in behind Pluto the Pup. Serendi^podous 11:08, 12 May 2010 (UTC)

It is unfortunate that Classical planet doesn't cover Uranus, Neptune or Pluto. We could perhaps do with a "Planets in culture" article where we could file this type of information.—RJH (talk) 18:42, 12 May 2010 (UTC)

Pronunciation

Why are there two pronunciations?
I thought Wikipedia used only one diaphonic transcription per article name, which is not to specify any one dialect, but a generic transcription for them all. And yet we have a non-North American transcription first and a North American transcription second. This is inconsistent with the other planet names which only have one for each planet name, not to mention other generic articles. --124.180.44.40 (talk) 05:55, 28 May 2010 (UTC)

Probably because the recording was of GA. But you're right: we don't transcribe the dialect of the recording elsewhere. — kwami (talk) 06:57, 28 May 2010 (UTC)

Trojans

The discovery of the first L5 Neptune Trojan was reported in Science (Science 10 September 2010: Vol. 329. no. 5997, p. 1304). The corresponding section in the article needs to be updated. Siravan (talk) 01:56, 23 September 2010 (UTC)

Vandalism

The summary syayes "Temperatures at the planet's centre, however, are approximately 5,400 K (5,000 °C)". The 2 references are unreachable, and this claim is not substantiated in te section of the article devoted to the planet core. Stephen Charles Thompson (talk) 05:03, 23 September 2010 (UTC)

I had no problem reaching the Suomi, Limaye and Johnson (1991) article. The illustration in that article confirms the statement. I'm not sure what the problem is with the other citation; perhaps their web server is malfunctioning?—RJH (talk) 18:56, 23 September 2010 (UTC)

Google works wonders: "Interior Models of Jupiter, Saturn and Neptune" -> https://www.gsi.de/informationen/wti/library/plasma2006/PAPERS/TT-11.pdf -- Kheider (talk) 19:06, 23 September 2010 (UTC)

Infobox image

Is there a reason why File:Neptune.jpg is used instead of the higher resolution File:Neptune Full.jpg? Nergaal (talk) 19:55, 11 October 2010 (UTC)

I don't think it matters; in either case the image downloaded is at the resolution specified on the page. I.e. you don't get the full image in the download. Also, I don't think either image is correct, color-wise. But the first one looks a little more natural.—RJH (talk) 21:35, 11 October 2010 (UTC)

OK, let's settle this once and for all

Uranus: cyan or aquamarine?

Personally, I vote aquamarine. Keraunos obviously votes cyan. Anyone else wish to contribute to this hugely important debate? Serendi^podous 10:14, 20 December 2010 (UTC)

I was having the same debate with myself after seeing his edit. See PIA00032: Uranus in True and False Color (as human eyes would see it): http://photojournal.jpl.nasa.gov/catalog/pia00032 -- Kheider (talk) 11:55, 20 December 2010 (UTC)

Many sites report either light blue or blue-green. Schmude (2008) notes that the color varies with telescope aperture. For what it's worth, I get 10,700 ghits for color uranus aquamarine, 7,900 ghits for color uranus cyan, 302,000 ghits for color uranus "light blue" and 351,000 ghits for color uranus "blue-green".—RJH (talk) 21:14, 21 December 2010 (UTC)

"Blue-green" redirects to cyan on Wikipedia, though I'm not sure whether it should. After all, viridian is blue-green, and no one would confuse it with cyan. Serendi^podous 22:38, 21 December 2010 (UTC)

Perhaps it could says something like, "The color of Uranus is considered light blue or blue-green (cyan), with the hue being dependent on the aperture of the telescope used to observe the planet." Citing Schmude above.—RJH (talk)

Well, the only reason this is an issue is to distinguish the colour of Neptune from the colour of Uranus. Neptune is blue, Uranus is blue-green. So I suppose we could just say that. Serendi^podous 17:57, 22 December 2010 (UTC)

Adams

The account of John Couch Adams in the Discovery section differs markedly from the cited references and also other Wiki pages. I'm not an astronomer so hesitate to plunge in. However..

The history page cited says that the 1843 letter to Airy was a request for data on Uranus not the results of his calculation. His claimed letter was to James Challis, not Airy in Sept 1845 and the cited 1846 paper in RAS Noticies doesn't contradict this. Chris55 (talk) 17:51, 19 January 2011 (UTC)

Actually, I think he says he did both. He first requested observations, which he received in February 1844. He then says he communicated the results of his first calculations Challis in September 1845, then sent slightly refined calculations to the Astronomer Royal (Airy) the following month.

"After obtaining several solutions differing little from each other, by gradually taking into account more and more terms of the series expressing the perturbations, I communicated to Professor Challis, in September 1845, the final values which I had obtained for the mass, heliocentric longitude, and elements of the orbit of the assumed planet. The same results, slightly corrected, I communicated in the following month to the Astronomer Royal."

—RJH (talk) 19:41, 19 January 2011 (UTC)

You don't get my point: the current article claims he had some results in 1843. That appears to be false and misleading. In fact, it appears that in Sept 1845 he was still investigating Biela's comet - whether he thought this was responsible for Uranus's perturbations I'm not sure. It would seem that neither he nor Le Verrier got very close to the truth in 1845 - the real action happened in 1846. Chris55 (talk) 19:56, 19 January 2011 (UTC)

I should perhaps clarify about your quotation: the account you quote by Adams is the historical one made in 1847 that has been widely questioned. If they were convinced about it in September 1845 why was it not seen by others at that time? In addition, the calculations by Adams seem to have been much less accurate than those of Le Verrier. Chris55 (talk) 23:46, 19 January 2011 (UTC)

No problem. I understand that the issue was controversial and any improvements are appreciated, if you can find suitable sources. Thanks.—RJH (talk) 23:56, 19 January 2011 (UTC)

A problem with your edits is your statement that begins, "After reviewing the documents, historians suggest that...". It appears that the text is claiming that all historians agree with this view, whereas only the authors of the cited source make that statement. You pretty clearly made that assertion by removing the "some" from the previous wording, so you'll need additional citations to affirm that statement.—RJH (talk) 16:49, 20 January 2011 (UTC)

you're right - the word "historians" is entirely redundant in that sentence now, I've removed it. Chris55 (talk) 18:36, 20 January 2011 (UTC)

That works for me. Thanks.—RJH (talk)

Neptune should be visible to the naked eye

While Brian Skiff failed to see it from Arizona, he says that it should be "straightforward with patience from Chile or elsewhere in the south."

If it is in opposition and high in the sky and from a location like Chili where you often have Bortle class 1 skies with limiting magnitude of +8 (if you have good eyes), then it should be visible. Count Iblis (talk) 01:13, 12 April 2011 (UTC)

That is really pushing the limit. Brian Skiff glimpsed HD 85828 (calling it mag ~8), but SIMBAD shows it as only mag 7.7. Bottom line is that even a professional failed to see Neptune with the naked eye. -- Kheider (talk) 01:32, 12 April 2011 (UTC)

Well, perhaps there aren't enough of these "star parties", like the Oregon star party in the Southern Hemisphere. Count Iblis (talk) 14:28, 12 April 2011 (UTC)

Edit request from 204.113.118.138, 6 May 2011

The beginning of the article says "Neptune is the eighth and farthest planet from the Sun in our Solar System." Shouldn't it say "the Solar System" instead of "our Solar System?"

204.113.118.138 (talk) 19:54, 6 May 2011 (UTC)

Yes indeed. Very well spotted. :) Serendi^podous 19:56, 6 May 2011 (UTC)

 Done by serendipodous. Monkeymanman (talk) 22:07, 6 May 2011 (UTC)

Typo in math markup of reference #12 mass ratio with earth

The '\b' in begin and the '\f' in frac are causing an error in reference 12 mass ratio with earth

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "http://localhost:6011/en.wikipedia.org/v1/":): {\displaystyle �egin{smallmatrix}�rac{M_{Neptune}}{M_{Earth}} \ =\ \frac{1.02 \times 10^{26}}{5.97 \times 10^{24}} \ =\ 17.09\end{smallmatrix}}

Should be

${\begin{smallmatrix}{\frac {M_{Neptune}}{M_{Earth}}}\ =\ {\frac {1.02\times 10^{26}}{5.97\times 10^{24}}}\ =\ 17.09\end{smallmatrix}}$

Not sure how to report this so I'm trying this Talk page thing. Please delete and accept my apologies if I goofed.

96.235.180.16 (talk) 18:22, 11 May 2011 (UTC)

I fixed the error. Ruslik_Zero 19:12, 11 May 2011 (UTC)

Calculation of position

I thought I remembered hearing once that the theoretical calculation of Neptune's position was actually done incorrectly, and it was only through a piece of good fortune that the prediction was anywhere close to the actual position where the planet was discovered. The article doesn't seem to mention this, though, so am I remembering it incorrectly? 86.160.208.15 (talk) 20:14, 17 May 2011 (UTC)

Yes I believe you're correct.[4]—RJH (talk) 20:52, 17 May 2011 (UTC)

Thanks. If this is verified I think it should be mentioned in the article. It seems fairly important. 86.181.168.97 (talk) 11:11, 18 May 2011 (UTC)

Note that there is a article Discovery of Neptune that this section summarizes. Hence, I think this should be mentioned there first. I'm not sure whether this point is at a high enough level for mention in a summary. Regards, RJH (talk) 14:48, 18 May 2011 (UTC)

Inconsistencies in date of completion of first orbit

There seem to be some discrepancies regarding the date of 12th July 2011 quoted for the completion of Neptune's first orbit since its discovery on 23rd Sep 1846, and the orbital period given in the info box: 60190 days or 164.79 years.

Firstly, 60190 days from the discovery date is 10th July 2011, not the 12th. (I'm fairly confident I've done that right, but please check my calculation. There were 40 leap years between those dates: every 4th year excluding 1900).

Secondly, the Nasa source cited for the figures in the info box has a few internal inconsistencies of its own, one of which is that the ratio of the orbital period given in Earth days and in Earth years is 365.2500, suggesting that one has been calculated from the other using this naive conversion factor. Both are given to a suspiciously high number of significant figures. The correct ratio is 365.2422 days per year, so at least one of the figures for the period from this source is not correct.

365.25 days is the length of the Julian year, which is used in astronomy. Saros136 (talk) 22:23, 20 May 2011 (UTC)

Really? Ok, my bad. I didn't realise that. But still... if they're saying Neptune's sidereal period is 60190.03 days, why do they say on the next line this is 164.791 x Earth's sidereal period, rather than 164.78845? The numbers given are not consistent. But that's a more understandable (minor) error than what I originally thought. Thanks. Bobathon (talk) 00:40, 21 May 2011 (UTC)

A second source by kpheider is given for the 12th July date which appears to be data output from ephemeris software – it's not clear what figures have been assumed in generating this output.

Another Nasa site referenced here gives a period of 60189 days or 164.79 years, which at least is internally consistent. The date for the completion of the first orbit since discovery by these data would be the 9th July 2011.

I'd be interested to know if anyone can confirm a more accurate figure for the sidereal orbit period of Neptune. But either way, unless I'm missing something, 12th July does not appear to be correct. Bobathon (talk) 03:23, 20 May 2011 (UTC)

Without double checking my work (I am kpheider), the orbital period of an object changes on a daily basis as a result of perturbations by the other gas giants. You can not just assume a single fixed value for the orbital period. -- Kheider (talk) 12:31, 20 May 2011 (UTC)

The definitive source for the July 12, 2011 date seems to be Dr. William Folkner at JPL/Caltech. He's using Neptune's return to the same heliocentric longitude as the defining date. There's a decent summary here. Regards, RJH (talk) 14:49, 20 May 2011 (UTC)

Thanks. I understand that the orbit period is subject to fluctuations, but it seems to me that there are two relevant quantities that can be clearly defined and presented in this article. The first is the mean sidereal orbital period of Neptune (the mean time taken to return to a given heliocentric longitude), and the second is the actual duration of this current orbit (time taken to return to the same heliocentric longitude as the defining date).

For Earth, the mean sidereal period is given as 365.256 363 004 in this reference. Although the uncertainty is not stated, a quantity is never given to twelve significant figures unless it has some meaningful value measurable to at least ten or eleven.

I find it hard to believe that we're not yet able to pinpoint the mean orbital period of Neptune to one part in 100,000. But even if we are, we should be able to present it within error bars, in the form 60189.0 ± 1.2 days, so that the state of knowledge on this quantity is made clear. I haven't seen a recent reference that clearly gives such a figure.

Regarding the second quantity – the duration of the first orbital period since discovery that RJH is referring to – from the source it's not clear if this is a definitive date. The period quoted in the article is 164.8 years; 164.8 years from the discovery date is indeed the 12th July 2011 ±18 days, which is not especially precise. If Dr Folkner has calculated the date of Neptune's return to the same heliocentric longitude and found it to be the 12th July, then that would be the date of the completion of the first period, which is the date I'm interested in, and I think is also the date relevant to this article. Currently it seems that the definitive source is a claim on twitter by Luke Dones that quotes Bill Folkner as saying it was the 12th July! It's hardly encyclopedic.

I'd like to know if anyone is aware of better information than this. Bobathon (talk) 18:47, 20 May 2011 (UTC)

I just double checked my heliocentric values (look at the bottom of the reference, and I still get the same values for RA/DEC.) I originally made the reference in 2007 to correct some mistakes on Wikipedia. -- Kheider (talk) 21:14, 20 May 2011 (UTC)

Thanks, Kheider. I'm sure the JPL ephemeris will be reliable and on the ball. Still, objectively there's no indication of what goes in or what degree of accuracy one can expect on anything that comes out. Is the conclusion that the first period is taking perhaps 3 days longer than an average period? Is that kind of variation about the mean (~0.005%) to be expected for a distant planet?

Still the same questions: when will the first period be completed and what's the degree of uncertainty on that; what's the mean sidereal period of Neptune and what's the degree of uncertainty on that. The ephemeris gives an answer to the first part of the first question, and that's all I wanted to know personally, so thanks for that. If anyone can clarify the other questions, that would be great – I think the article needs it. Bobathon (talk) 22:01, 20 May 2011 (UTC)

I'd like to add an additional comment the reliability of the JPL ephemeris dates. Following Kheider, I used their HORIZONS ephemeris to find the dates of the completion of the 1st, 2nd, 3rd and 4th orbits of Neptune since discovery, and found the duration of these orbits to be 60192, 60197, 60206 and 60208 days respectively. (Running backwards, the duration of the orbits prior to discovery were 60184, 60176 and 60174 days respectively.) I don't believe these large increases are anything like the orbital period variation that Neptune can be expected to exhibit. I would suggest from this that their extrapolation is not designed to be reliable to less than several days over a period of centuries. The ephemeris for July 2011 may be precise, as extrapolation is minimal, but those of 23 Sept 1846 are not reliable to the nearest day. As these are required for the suggested date of 12th July, this date appears to be questionable.

This paper by E.M. Standish of JPL presents some indication of the degree of precision involved in the JPL ephemeris, and figure 8 suggests reliability of heliocentric longitude for Neptune to ±0.5" (=0.03" R.A., I assume) over the period 1600-2200, which would make the ephemeris accurate to within one day for that whole period, and within a few hours over the period since 1846. I'm not sure how this tallies with the dates actually given by the ephemeris for the orbital periods of Neptune.

FYI, the dates the ephemeris gives for heliocentric R.A. of 22 05 40.444 are 1352-06-03 0:30, 1517-03-02 12:48, 1681-12-12 18:54, 1846-09-23 23:00, 2011-07-12 20:57, 2176-05-04 19:07, 2341-03-07 20:14, 2506-01-09 13:30. I based them around 23:00 UT on date of discovery because Galle made the discovery "shortly before midnight" ("The Neptune File", Tom Standage, Berkley Trade 2001, p.121) in Berlin (local mean time UT+0:53). Apologies for the excessively detailed discussion entries, but I felt it was important to establish whether there's any real reason to believe that the date of 12th July 2011 isn't based on duff data, especially if the world is intending to celebrate it in a few weeks' time. So far I don't believe that there is. Bobathon (talk) 14:17, 22 May 2011 (UTC)

I've done some thorough calculations using HORIZONS data, and presented the results here. The correct date should be 11th July 2011, not the 12th as cited in the article. The difference is due to the motion of the Sun during Neptune's orbit (0.0033 A.U. at 70º to the radial vector to Neptune) which throws out the coordinates used in the calculation done by Kheider (and Bill Folkner, who I've had some communication with). I'm too wary of the issues around use of own work / citing blogs / etc. to change the article, but there it is. :) Bobathon71 21:50, 1 July 2011 (UTC)

The problem with this approach is Wikipedia's WP:OR policy. Regards, RJH (talk) 15:57, 3 July 2011 (UTC)

Interesting way to look at it Bobathon71. But I am not sure a barycentric solution is any more proper than a heliocentric solution. I might try and play with this later if I get a chance. -- Kheider (talk) 16:04, 3 July 2011 (UTC)

Thanks for identifying the policy, RJH. It's one I'm very supportive of. Kheider, I'd be interested in what you can find. To me, heliocentric solution seems very sensible for any definition in which the role of the sun is dominant, such as equinoxes, perihelion or anything from the frame of reference of the planet itself; but it doesn't make a lot of sense for anything describing the orbit, or for sidereal years. But I agree, if something like this is defined at all then it will be by some convention that has some degree of arbitrariness about it. Perhaps we could go with '10th-12th depending on definition' as you suggested elsewhere. Bobathon (talk) 01:26, 4 July 2011 (UTC)

Here are a couple of images that might be more convincing: Neptune-Sun distance and Neptune-barycentre distance. Bobathon (talk) 16:23, 4 July 2011 (UTC)

I've made the change given that there are also now notable sources quoting the 11th. And because it's correct :) Feel free to let me know if I'm out of line there. Bobathon71 19:40, 10 July 2011 (UTC) — Preceding unsigned comment added by Bobathon71 (talk • contribs)

I disagree that July 11th is a better solution. I think most people think in heliocentric terms. Neptune physically orbits the Sun, even if the barycenter is outside the surface of the Sun. I will allow the barycentric solution first since it comes a day earlier, but I do not agree that it is a better solution. -- Kheider (talk) 21:28, 10 July 2011 (UTC)

Surely the two plots I referenced earlier (Neptune-Sun distance and Neptune-barycentre distance), as well as the laws of gravity, make it incontrovertible that Neptune takes a far, far more periodic, smooth and Keplarian trajectory around the solar system barycentre than it does around the Sun. Is it the job of an encyclopaedia to reproduce what most people think, or what is in line with the laws of planetary dynamics? The Solar System is a gravitationally bound set of objects, and the Sun is one of them. Neptune doesn't orbit the Sun for precisely the same reasons that it doesn't orbit the Earth. Sorry, I don't mean to sound confrontational at all; I'm interested if you actually have a reason for disagreeing rather than just an opinion... Bobathon (talk) 21:44, 10 July 2011 (UTC)

Neptune orbits the Sun, first and foremost. Yes, the barycenter is outside the surface of the Sun. But you MUST define what "orbit" you are quoting. Now the article defines a barycentric solution and a heliocentric solution. If the heliocentric solution came before the barycentric one, I would list it first. -- Kheider (talk) 21:56, 10 July 2011 (UTC)

I haven't argued against defining what orbit is being quoted, that's fine. The original version didn't define what orbit was in use, so I followed what was there.

I gave reasons why it's clear that Neptune follows a far more typical orbit around the barycentre than the torturous path it follows in its motion relative to the Sun, and you restated an opinion. I'm still curious as to whether you have a reason for your view. You might also want to take issue with the introductory definition of orbit and the references it's based on.

Also, forgive me if I restore something of the two sentences from a previous edit, which were making two separate points, one of which was lost in your alterations. Bobathon71 (talk) 22:56, 10 July 2011 (UTC)

The point of the second sentence is that if you look from the point of view of the Sun at Neptune on 23/9/1846 and again on 11/7/2011, it will appear to be at a different longitude. The reason for this is nothing to do with perturbations: it is because the Sun (from which you are viewing Neptune) has moved. Bobathon71 (talk) 23:36, 10 July 2011 (UTC)

The references I added were definitions of orbit, not barycentre. I added them because the section is on the orbit of Neptune. Please, Kheider, don't act as if you own this page. Bobathon71 (talk) 23:36, 10 July 2011 (UTC)

This article is about Neptune. This is not the article to define and directly reference what an orbit/barycenter is. -- Kheider (talk) 23:41, 10 July 2011 (UTC)

Well, approximations are fine in casual writing but an encyclopedia is about truth. Neptune orbits the barycenter. The Sun orbits the barycenter. It's just considerate enough to stay near it. 12.196.0.56 (talk) 03:15, 11 July 2011 (UTC)

The Sun orbits the barycenter of our galaxy if you want to get that technical. The Sun stays near the barycenter of the solar system because it is 1,047x more mass than Jupiter. -- Kheider (talk) 04:20, 11 July 2011 (UTC)

If you want to get technical, then it's the barycentre of the Solar System, not than the Sun, that smoothly orbits the barycentre of the galaxy. Like every other member of the Solar System, the Sun's dynamics are dominated by its motion within the Solar System. It is continuously being pulled towards Jupiter over a thousand times more strongly than it is towards the centre of the Milky Way. And the pull towards the Milky Way is not only tiny, but it affects everything in the Solar System in precisely the same way, so has no effect on any of the dynamics within the Solar System - at least none we could ever hope to measure. There are very good (and fairly obvious) reasons why the International Celestial Reference System doesn't employ the barycentre of the galaxy as the origin of coordinates. Bobathon71 (talk) 12:19, 11 July 2011 (UTC)

The galactic tide likely effects the Oort cloud. -- Kheider (talk) 15:04, 11 July 2011 (UTC)

True dat. Bobathon71 (talk) 15:55, 11 July 2011 (UTC)

I'm a bit confused by your concerns about the motion of Neptune relative to the barycentre. That's what a barycentric orbit is. Bobathon71 (talk) 15:58, 11 July 2011 (UTC)

Your blog entry shows that in 2011 Neptune was 347,750 km closer (0.0077% closer) to the Solar System barycentre than it was in 1846. (Using heliocentric distances on 1846-Sep-23 23:00 UT Neptune was 30.011455AU from the Sun and on 2011-Jul-11 22:00 30.00795AU from the Sun, for a movement of ~524,000km towards the Suns physical centerpoint.) As you know this movement is also the result of perturbations of Neptune in addition to the Sun going around the barycenter. I still am not sure "the motion of the Sun in relation to the barycentre" is a better statement than "the motion of the Sun and Neptune in relation to the barycentre". -- Kheider (talk) 17:24, 11 July 2011 (UTC)

Ah, I see. When Neptune returns to its discovery longitude, it is at a different radial and perpendicular-to-plane co-ordinates, but neither of these have any impact on the date of completion of its first orbit, no matter whether you're using barycentric or heliocentric coordinates. It will have some minuscule effect on the difference between the two events, because of the tiny change in parallax, but no more than that. So it's not relevant to the paragraph on the date of completion of the first orbit; but it may be worth mentioning in a different paragraph as a general point about the nature of the orbit itself.

The reason the two dates (11th & 12th) are different is because of the tangential displacement of the Sun relative to the barycentre between 1846 and 2011. If you displace yourself sideways, the bearing you take on a distant object will change; whereas if that object moves a similar distance towards you (or vertically), that will have no effect at all. Bobathon71 (talk) 17:48, 11 July 2011 (UTC)

Largest known Kuiper belt object

Where the article has "the largest of the Kuiper belt objects, [[Pluto]]" it should have "the largest known Kuiper belt object, [[Pluto]]." Is there a reliable source that says that people are not likely to find any Kuiper belt objects larger than Pluto? - Fartherred from an untrusted terminal 207.224.85.91 (talk) 17:57, 1 June 2011 (UTC)

The statement about KBOs is questionable in any event, since Eris (dwarf planet) probably has more mass than Pluto. From what I've read, speculation about larger objects beyond 50 AU continues, so the answer to your question may be a qualified "no". Regards, RJH (talk) 18:58, 1 June 2011 (UTC)

I modified the sentence according. Thank you for your observation. Regards, RJH (talk) 14:41, 26 June 2011 (UTC)

Didn't we decide aeons ago that "the Kuiper belt" was defined as the classicals plus the resonants? If so then Pluto is the largest known Kuiper belt object. Serendi^podous 15:09, 26 June 2011 (UTC)

You are correct. My bad. Regards, RJH (talk) 21:59, 6 July 2011 (UTC)

That is one more small error disposed of. User:Fartherred from 207.224.85.91 (talk) 09:37, 9 July 2011 (UTC)