Talk:Jupiter/Archive 3

Gradual transition between gas and liquid
In its current state, the article says "there is probably a smooth gradation from gas to liquid" between upper and lower levels. I don't think there is any question about this. You can only have a liquid surface below the critical temperature for that liquid. The critical temperature for hydrogen is 33 K. What sources I can find indicate that the atmospheric temperature bottoms out at around 110 K in the stratosphere, and gets steadily warmer as one goes deeper. These temperatures have been measured by the Galileo probe, so one can be fairly confident of them.

Many sources, such as, talk about an "ocean" of hydrogen, but they are making the point that the hydrogen is compressed enough that it is reasonable to think of it as a liquid. At those pressures the distinction is unclear anyway.

Can somebody say why doubt should be expressed about the transition from gas to liquid? Mark Foskey 03:02, 6 November 2007 (UTC)
 * You need an equation of state for high-pressure hydrogen to decide this question. There is no easy answer, since we can't measure it directly. Michaelbusch 05:11, 6 November 2007 (UTC)
 * I'm still confused. The critical temperature and pressure for molecular hydrogen are about 33 K and 13 bars, right?  Is there some possibility of a phase transition reappearing between gaseous and liquid molecular hydrogen at high pressures?  I've never seen a phase diagram like that, but I haven't seen that many.  I realize that there is uncertainty about the existence of a plasma phase transition between the molecular and metallic levels (although the article right now acts as if that is known).  Mark Foskey 03:32, 8 November 2007 (UTC)

Gravity
Could someone please tell me what Jupiters average gravitational field strength is. I don't think it actually states it in the article. It says the field strength at the equator is ~2.4 times greater than Earth because of centripetal forces, but if its mass is 300 odd times greater, then shouldn't the average field strength be ~300 times greater? Thanks. ArdClose (talk) 14:01, 19 December 2007 (UTC)
 * But its radius is 11 times greater, so the average gravity acceleration is $$318/11^2\approx 2.5 $$ earth's. Ruslik (talk) 14:39, 19 December 2007 (UTC)
 * The "Orbit and rotation" section discusses the equatorial acceleration in a little more detail. I'm not sure that it makes sense to list the "average" gravitational strength for a planet as oblate as Jupiter.&mdash;RJH (talk) 16:41, 19 December 2007 (UTC)


 * Ah ok, thanks for clearing that up. ArdClose (talk) 17:26, 19 December 2007 (UTC)

The values shown in the infobox for the "Equatorial surface gravity" are 24.79 m/s^2 (which is 2.52787649 g, being g=9.80665 m/s^2) and 2.358 g, so they differ in ~0.17 g. In my opinion if they express different facts, as the account of the centripetal acceleration, it should be made clear with an additional footnote. Otherwise the reader will assume they are equivalent. —Preceding unsigned comment added by 79.147.39.120 (talk) 11:54, 31 December 2007 (UTC)
 * I went ahead and removed the 2.358 g value as it lists no source for the conversion. The 24.79 is from the Jupiter Fact Sheet ref. Thank you for pointing it out.&mdash;RJH (talk) 18:16, 1 January 2008 (UTC)


 * It seems that the removed 2.358 g value came also from the Jupiter Fact Sheet, where it is stated as: "Acceleration (eq., 1 bar) (m/s2)  23.12" (we have to divide it by 9.80665).
 * In that Fact Sheet, "Gravity" tells about the strength of the gravity field at the equator, while the lower "Acceleration" value is given for a point fixed to the rotating equatorial surface or atmosphere. Actually both values were correct and the consequences of being different are shown in the "Orbit and rotation" section of this article.
 * However, according to http://en.wikipedia.org/wiki/Surface_gravity, the surface gravity is "the gravitational acceleration experienced at its surface"; therefore there's no account for other accelerations experienced -such as the one derived from rotation- and I think that the infobox's gravity is correct after the removal. The equatorial acceleration is an interesting data to include as well, but it would require an additional footnote or its own label.
 * Thank you all for your wikiwork. —Preceding unsigned comment added by 81.34.102.93 (talk) 17:52, 3 January 2008 (UTC)

Reduce precision of elements in infoboxes?
I reduced the precision in the table, but I wonder if we could reach a consensus here on these infoboxes in general. (Or should I revert?) The MoS says ''Avoid over-precise values where they are unlikely to be stable or accurate, or where the precision is unnecessary in the context. (The speed of light in a vacuum is 299,792,458 metres per second is probably appropriate, but The distance from the Earth to the Sun is 149,014,769 kilometres and The population of Cape Town is 2,968,790 would usually not be, because both values are unstable at that level of precision, and readers are unlikely to care in the context.)'' I'm guessing that this consensus was reached after the template was created, and the template now conflicts with wiki policy. Saros136 (talk) 19:21, 31 January 2008 (UTC)


 * I think that 7-8 digits, as you have it, is plenty for most measurement purposes. Eight will allow you to convert years to seconds, for example. Rounding an orbital distance on the order of 108 kilometers to the nearest hundreds will still put you inside the radius of the planet.&mdash;RJH (talk) 18:21, 1 February 2008 (UTC)

Proposed Change
"Jupiter (pronounced /ˈdʒuːpɨtɚ/[9]) is the fifth planet from the Sun and the largest planet within the solar system."

Perhaps it would be better to change "solar system" to "Milky Way", since by saying "the solar system" it's very ambiguous as to which one you mean. —Preceding unsigned comment added by 70.55.138.55 (talk) 00:45, 4 March 2008 (UTC)


 * The Milky Way is a galaxy made up of thousands of Solar systems. Our Solar System consists of our sun and eight planets of which Jupiter is one.  The proposed option is not a valid fix since it talks about two completely different things. I guess we could change it to "our solar system."  Would that solve the question of ambiguity?   Jons63 (talk) 01:01, 4 March 2008 (UTC)


 * No, the Milky Way is made up of billions of stellar systems. The Solar system is one specific stellar system, that of the star Sol — our sun. kwami (talk) 03:26, 4 March 2008 (UTC)
 * Another problem with the proposal is that Jupiter is not the largest planet in the Milky Way. Saros136 (talk) 07:39, 4 March 2008 (UTC)
 * Perhaps, then, the Solar System should be capitalized in the intro sentence... Also, the lede refers to the 'rapid rotation' as if that is a known. Wikiak (talk) 07:18, 30 June 2008 (UTC)
 * Sol system is the term usually used to donate our own solar system --68.114.130.179 (talk) 19:41, 25 October 2008 (UTC)

Atmosphere Helium Mass percentage
I note that the mass percentage of helium in the article is based on helium 4 but the article states gas as a likely primordal material from the formation of the solar system. Isn't helium 3 the major isotope in space and helium 4 an Earthly artifact arising from alpha particles released in nuclear decay of radioactive minerals? Given this, mass percentage of the gas would be closer to 18% rather than 24% (Helium would be half again as dense as diatomic hydrogen rather than twice as dense.)

Howard Woods Eagle Idaho —Preceding unsigned comment added by 71.215.28.150 (talk) 12:40, 11 March 2008 (UTC)


 * 25% of the (atomic) matter in the universe was converted to Helium-4 during the Big Bang. By comparison, Helium-3 is just a trace element.&mdash;RJH (talk) 15:28, 11 March 2008 (UTC)

nieuws: het is juist gebleken dat jupiter GEEN planeet meer is!! Jupiter heeft een gaskern waardoord het GEEn planeet is! —Preceding unsigned comment added by 84.197.190.61 (talk) 17:48, 23 November 2008 (UTC)

nieuws : het is juist gebleken dat jupiter toch een planeet is ! —Preceding unsigned comment added by 81.245.211.169 (talk) 17:51, 23 November 2008 (UTC)

First photograph of Jupiter has distorted dimensions
Being an avid amateur astronomer who looks at it often through a telescope, I thought the first image of Jupiter in this article didn't look quite right. Based on how oblate Jupiter is (having an equatorial radius that is almost 7 percent larger than its polar radius), it didn't look as bulged out at the equator as I am used to seeing it.

I decided to do some simple pixel measurements of this photo. I was very surprised, and a bit disappointed, to find that the image has been made artificially circular. When I measure the apparent horizontal diameter in pixels (i.e. equatorially), I get a span of 783 pixels. Going vertically through the poles, I get 778 pixels. This is a ratio of 1.006, which is only 0.6 percent, instead of the 1.07 I was expecting.

I know the source of this photograph is NASA, but I wonder if we can find a photograph that is of comparable crispness and detail, but without the distortion of its true shape. This is not just aesthetics, but conveys something important about the science of the planet: it is huge, gaseous, and rotates once every 10 hours, making it bulge out more than any other planet.

Failing that, should note be made in the article that not only has the photo been processed for contrast and color, but the planet's aspect ratio has been altered as well?

CosineKitty (talk) 01:52, 3 April 2008 (UTC)


 * Good catch! Yes it is odd that NASA would do something like that. The egdes of the image also look as if they have been artifically masked out. The full-sized image lacks anti-aliasing along the edges, which seems like a dead giveaway that it was doctored. Compare, for example, to the image at http://photojournal.jpl.nasa.gov/jpegMod/PIA04866_modest.jpg which has a nice clean edge.
 * Here is NASA's photojournal of 303 images:
 * http://photojournal.jpl.nasa.gov/target/Jupiter
 * There are also a few images in the commons:
 * http://commons.wikimedia.org/wiki/Category:Jupiter_%28planet%29
 * Thanks.&mdash;RJH (talk) 22:13, 3 April 2008 (UTC)


 * Of those photos, I like http://photojournal.jpl.nasa.gov/jpegMod/PIA04866_modest.jpg the best. Because only part of Jupiter is illuminated, doing the oblateness calculations is much more challenging.  It's a fun Sunday project though.  I will post again here when I come to a conclusion.  If it turns out to be a more true-to-life depiction of Jupiter's shape, would other people here consider it OK to be the replacement for the distorted photo at the top of the article?  CosineKitty (talk) 22:28, 6 April 2008 (UTC)


 * Follow-up: I just realized that there is more than one use of the distorted photo I am complaining about in this article. Also, the suggested replacement already appears captioned as a Cassini photo.  So a simple replacement of the distorted photo would create a redundant experience for the reader.  I am still looking for non-copyrighted photographs of sufficient quality to nominate here. CosineKitty (talk) 22:34, 6 April 2008 (UTC)


 * This one also looks decent:
 * http://commons.wikimedia.org/wiki/Image:PIA02873.jpg
 * &mdash;RJH (talk) 22:52, 6 April 2008 (UTC)

Proposed addition: where can you see Jupiter now?
I'm a newbie to editing Wikipedia, and as such I thought it best to ask the opinions of those who know and love the Jupiter article for their thoughts. Don't want to step on anyone's toes.

It might be nice if the page included some information on where Jupiter could be seen in the sky. There is a small web module which does just this, displaying information as text in an iframe. I should disclose that I wrote this. There are some snippets of HTML here which show the info in a couple of different box geometries. Possibly a less obtrusive alternative might be to link to a page showing similar positional information for all the major planets, such as this.

If the consensus is that this would make a worthwhile addition, then please feel free to add it in either form.

Thanks!

Mrchutney (talk) 06:16, 17 April 2008 (UTC)


 * Sorry but wikipedia is not an ephemeris; in the past, comparable information has been removed from the Solar System articles (such as some of the asteroid pages). My personal preference is that we don't keep including information that is time-dependent, as that needs steady upkeep. There is an example of this in the Observation section (but others seem to differ.) You can always go to the "HORIZONS System" reference for ephemeris information. If there is a better site for an ephemeris, it can always be added to the External links.&mdash;RJH (talk) 15:28, 17 April 2008 (UTC)

Zodiacal "sweep"
I find the description that Jupiter's 11.86-year orbit corresponds to the twelve zodiacal constellations somewhat misleading. That's apparent superficially, but my understanding is that there are thirteen constellations in the Zodiac used in astronomy--Ophiuchus being the "thirtheenth"--rather than the classical twelve derived from astrology. Of course, the modern plots on the sky of any constellation were developed out of convenience--perhaps arbitrarily and haphazardly--but all major Solar System objects pass through Ophiuchus. Correct? Just suggesting some clarification on this part the article might be helpful. 68Kustom (talk) 02:47, 19 April 2008 (UTC)
 * Do you have some evidence that the Babylonian (not the Greeco-Roman or Druidic) zodiac used 13 constellations? All the references I check seem to indicate they used 12. (For example)&mdash;RJH (talk) 21:26, 19 April 2008 (UTC)


 * No, I didn't mean that. Ancient cultures plotted the ecliptic along 12 constellations. Modern astronomy added Ophiuchus probably in order to fill a 'gap'--it's really only a small area that juts down to the ecliptic.  But Jupiter still should pass through Ophiuchus; 13 constellations, currently. 68Kustom (talk) 22:43, 21 April 2008 (UTC)


 * I changed a "the" to "their". Hopefully it is sufficiently clear now.&mdash;RJH (talk) 15:46, 22 April 2008 (UTC)

1953 experiment
If someone's bored, the 1953 experiment's conditions are now thought to be non-representative of the atmosphere of primordial Earth. —Preceding unsigned comment added by 64.222.149.167 (talk) 16:22, 1 May 2008 (UTC)
 * Do you have a source, per chance? Thanks.&mdash;RJH (talk) 14:49, 30 June 2008 (UTC)

GRS
the great red spot on jupiter is made up of swriling winds and gasses that are harmful if yiu breathe them —Preceding unsigned comment added by 142.25.147.98 (talk) 17:24, 23 May 2008 (UTC)
 * Sounds like some of the park service outhouses I've visited. Glad I don't live there. ;-)&mdash;RJH (talk) 20:07, 23 May 2008 (UTC)

Hilfe, Hilda!
the schematic with 'Trojans' (in Interaction with the Solar System) shows 'Hildas', as yet another group of asteroids. Who are they? :-) Wikiak (talk) 07:39, 30 June 2008 (UTC)
 * There's an article about them at Hilda family. :) --Patteroast (talk) 12:38, 30 June 2008 (UTC)
 * kewl! By Jove, add a link! :-) Wikiak (talk) 10:19, 1 July 2008 (UTC)
 * There is a discussion of asteroid groups and families that have orbital resonances with Jupiter at Asteroid_belt.&mdash;RJH (talk) 15:03, 1 July 2008 (UTC)

Erratum
<< [...] comet Shoemaker-Levy 9 [...] collided with Jupiter and gave informations about the structure of Jupiter. >>

Someone please change "informations" into "information". It's an uncountable word (no plural) in most English uses, such as this one. Thanks! 81.44.142.232 (talk) 22:59, 1 July 2008 (UTC)
 * Done. Thank you for the catch.&mdash;RJH (talk) 17:14, 2 July 2008 (UTC)

Inaccuracy
In the Magnetosphere section, the image is not the aurora borealis; it's the moons trailing through the magnetosphere. —Preceding unsigned comment added by 72.160.132.159 (talk) 00:02, 13 July 2008 (UTC)
 * The image is described on an Astronomy Picture of the Day caption as Jovian aurorae. Yes the display is caused by the interaction of the moons with the magnetosphere, but they don't actually show the moons in this image.&mdash;RJH (talk) 14:31, 25 July 2008 (UTC)

Grammer fix
"Jupiter, along with Saturn, Uranus and Neptune, is classified as a gas giant."

This sentence doesn't read properly and should be modified to something along the lines of:

"Jupiter is classified as a gas giant, along with Saturn, Uranus and Neptune."
 * A resonable suggestion. The text has been updated.&mdash;RJH (talk) 15:04, 27 July 2008 (UTC)

JUPITER
what is the average temperature of jupiter? is jupiter has an atmosphere? —Preceding unsigned comment added by 161.139.212.162 (talk) 04:17, 27 July 2008 (UTC)
 * Temperature can vary by latitude, season, depth and weather conditions. I'm not sure how we would come up with an average temperature for all of those factors. Yes there is an atmosphere on Jupiter.&mdash;RJH (talk) 15:02, 27 July 2008 (UTC)

Merger proposal
Jupiter's magnetosphere has not improved significantly since it was created in 2006. Most of its material is unsourced and it could probably be merged back with this article.  Serendi pod ous  15:46, 7 August 2008 (UTC)
 * It looks like there is already more about Jupiter's magnetosphere in the current article and it is cited here, so I'm not sure whether it would be worth merging. (No offence intended to the editors, of course.) But I do think it's a topic worthy of expansion.&mdash;RJH (talk) 16:47, 7 August 2008 (UTC)

The Jupiter article is big enough, it would be good to keep a separate article for more detail on the magnetosphere. Graeme Bartlett (talk) 02:32, 8 August 2008 (UTC)
 * Since I'm trying to get a Jupiter subtopic for the Solar System FT off the ground, I would prefer it if that article weren't there. So if it's all right with everyone I'll just redirect it to the magnetosphere section. Unless someone wants to get it up to GA level within the next month or so.  Serendi pod ous  08:10, 8 August 2008 (UTC)
 * Jupiter's magnetosphere needs its own article of course, but I agree that it can be redirected as a temporal solution. Ruslik (talk) 08:46, 8 August 2008 (UTC)


 * If the Featured Topics system discourages the existence of valid but insufficiently developed forked topic articles, I'm unclear about the benefit of even having FTs.&mdash;RJH (talk) 15:52, 8 August 2008 (UTC)
 * The system is designed to prohibit what they call "cherry picking", which basically means that EVERY SINGLE article related to a specific topic must be of GA or higher or the topic won't be considered. This makes nominating an FT a difficult proposition.  Serendi pod ous  09:06, 9 August 2008 (UTC)
 * I suppose that is of some value in the process, although I'm still not sure the process itself is beneficial. What happens if an editor should decide to start working on a Jupiter magnetosphere article and that won't be complete for many months? But, it's not really important. Thanks.&mdash;RJH (talk) 23:33, 9 August 2008 (UTC)

Great Red Spot
The GRS is a low orbit moon
 * May I say, that is quite possibly the oddest Solar System-related hypothesis I have ever seen, and I've read Worlds in Collision AND The 12th Planet!  Serendi pod ous  15:09, 19 November 2008 (UTC)

Jupiter's color
I thought Jupiter's global disc is multicolor on the planet's disc, it sometimes have blue purple, pink, green, magenta, alot more than just orange white and brown. Jupiter I thought have yellow sometimes. Can I include this somewhere in the article? jupiter just spin too fast for spacecraft to see colors changing, that's why.-- Freewayguy What's up? 22:49, 26 August 2008 (UTC)


 * Well, it would be good to have, but color stuff can be tricky, see f.ex. Talk:Stellar classification where color is a major issue and angry D65 standard guys may walk in and change every color, so it would also be nice to have external sources, amateur astronomers would be best, because the professionals just use some electronic stuff and apply some filters, and out comes false-color images, nice to behold, but the colors are false . Said: Rursus (☻) 18:25, 15 October 2008 (UTC)

God
May we declare Jupiter, the planet, being a god? For those who prefer other gods or no god, one may optionally add the epithet "false". Said: Rursus (☻) 18:33, 15 October 2008 (UTC)


 * Another interesting option would be Galactic Center. Said: Rursus (☻) 18:36, 15 October 2008 (UTC)


 * Neither. This would be a violation of NPoV.&mdash;RJH (talk) 20:13, 15 October 2008 (UTC)


 * NPoV on the talk page? Oh, come on. Where's the fun in this place? Said: Rursus (☻) 07:42, 17 October 2008 (UTC)


 * Well I assumed that you were discussing the article. Otherwise, it would seem to be off topic.&mdash;RJH (talk) 16:31, 18 October 2008 (UTC)

constellation, or sign?
I hesitate to add anything about astrology to this article, but in this case I think it may be justified. The article currently states that Jupiter's 12-year orbit corresponds to the dozen constellations of the zodiac. That is incorrect: it corresponds to the dozen signs of the zodiac, which were named after nearby constellations. Jupiter's orbit, like astrological signs, has nothing to do with the stars. In fact, AFAIK the signs were defined by Jupiter's orbit, so they do more than just correspond.
 * Yes, that change makes sense to me.
 * Okay, added it in. kwami (talk)

I also added a 'dubious' tag about Jupiter's orbit being about two fifths that of Saturn. If it's about two fifths, then they are not in a 5:2 resonance, as the following line states. kwami (talk) 08:22, 27 October 2008 (UTC)
 * I added a reference. The abstract states the planets are "near the 5 : 2 mean-motion resonance".&mdash;RJH (talk) 14:45, 27 October 2008 (UTC)


 * Then they are not in resonance? kwami (talk) 18:21, 27 October 2008 (UTC)
 * I don't have access to the article, but it looks as though they are in resonance. The word "about" would be inappropriate in that case, so I removed it. (The difference from an exact two fifths is negligible.) kwami (talk) 18:28, 27 October 2008 (UTC)


 * Okay. It's unfortunate that Icarus does not post their older articles for public reading. I think they would be invaluable for Solar System articles.&mdash;RJH (talk) 18:39, 27 October 2008 (UTC)

New core model
I believe the following is the paper being reported in the news story about "Jupiter Has Large, Rocky Core Surrounded By Layer Of Ice":



&mdash;RJH (talk) 20:01, 26 November 2008 (UTC)

Radio emissions
The section "Ground-based telescope research" claims that there are three types of radio emissions from Jupiter, lists two, then mentions the emission of heat. Heat is not a radio emission. 62.30.249.131 (talk) 09:28, 5 December 2008 (UTC)


 * Thermal radio emission from Jupiter and Saturn.&mdash;RJH (talk) 19:00, 5 December 2008 (UTC)

Future probes
Explanation of replacement of JIMO and JEO information with EJSM:


 * JIMO was cancelled 4 years ago. It should not be in a section called Future probes.


 * Likewise the Jovian Europa Orbiter is now past tense. It was part of ESA's "Technology Reference Studies", which was superceded in 2007 by ESA's "Cosmic Vision":http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=33170 which includes the Europa Jupiter System Mission.Charvest (talk) 07:27, 23 January 2009 (UTC)


 * Thank you for the explanation. Some of us tend to be a little conservative about the removal of material, mainly because of past vandalism and such.&mdash;RJH (talk) 20:11, 24 January 2009 (UTC)


 * That was why I deleted JIMO and JEO, but I've rewritten the section now, and retained references to JIMO and JEO as being superceded by EJSM. Charvest (talk) 22:48, 24 January 2009 (UTC)
 * Thanks.&mdash;RJH (talk) 17:49, 21 February 2009 (UTC)

Issue with "physical characteristics" box
I noticed something which may be potentially confusing. In the Physical characteristics box, the following information can be seen:

Equatorial radius 	71,492 ± 4 km[4][5]

11.209 Earths

Polar radius 	66,854 ± 10 km[4][5]

10.517 Earths

My issue is measuring this in terms of "Earths". Because here, the equatorial radius of Jupiter is in fact equal to 11 times the Earth's radius, not its diameter. If you're just talking about "Earths" as a measurement, people would tend to take this as a visual aid and consider the entire Earth, meaning its diameter, as opposed to just its radius. This makes it unclear if Jupiter itself [diameter] is 11 times the size of Earth, or if its radius is 11 times the size of Earth.

Its technically appropriate to list the radius instead of the diameter, and I'm a big fan of comparing measurements to Earth as a visual aid. So I'm not sure on how to change this, so I'll just mention it to you guys instead. Harley peters (talk) 00:05, 26 January 2009 (UTC)
 * Yes I agree that it would be less ambiguous to say "Earth radii" rather than "Earths".&mdash;RJH (talk) 21:01, 26 January 2009 (UTC)

number of moon
I think Jupiter has more than 63 moons. Isn't the number of moons close to 10,000 or so? —Preceding unsigned comment added by 67.137.31.66 (talk • contribs)
 * I'm guessing that you are referring to Jupiter's ring system? It probably depends a lot on how you define the word 'moon'. Perhaps there needs to be a definition of 'moon' (vs. 'moonlet' vs. ring system) along the same vein as how the IAU defines a planet? C.f. Natural_satellite.&mdash;RJH (talk) 17:47, 21 February 2009 (UTC)

Equatorial gravity
I think that since of very high equatorial rotation speed centrifugal force can not be neglected when calculating equatorial gravity. I have calculated the centrifugal accelaration to be something like 2-2.5 m/s2! Also i would like someone smarter than me to exactly calculate polar gravity(I got ~28m/s2). —Preceding unsigned comment added by IvanStosic (talk • contribs)
 * If you had read the article, you would have probably discovered the third paragraph of this section: Jupiter.&mdash;RJH (talk) 19:48, 22 February 2009 (UTC)

Twin system
As the article already mentions, Jupiter's barycenter with the Sun actually lies above the Sun's surface. Should we expand on that, and say that because of that, Jupiter doesn't technically orbit the sun, and the solar system might be considered a twin system of the sun and Jupiter? - Shaheenjim (talk) 12:31, 1 March 2009 (UTC)


 * Thank you again, Shaheenjim, for your references in the Moon article. And I responded to your thoughts about a Sun/Jupiter twin system here.  --Paine Ellsworth (talk) 17:15, 1 March 2009 (UTC)

juipiter
hi why is juipiter so big —Preceding unsigned comment added by 90.219.151.229 (talk) 15:38, 14 March 2009 (UTC)
 * To answer your question, you might take a look through formation and evolution of the Solar System.&mdash;RJH (talk) 18:35, 30 March 2009 (UTC)

The sun having a mass of about 1050
Jupiters is context that readers would appreciate and I think it should be in the article.Instead of being bold, I'm suggesting it here in deference to article's protection status.Rich (talk) 02:44, 10 May 2009 (UTC)
 * The mass ratio is mentioned on Jupiter mass, but I think it would be of value to mention this in the Mass section. It would provide some perspective (even though the end of the Mass section already does this to some degree).&mdash;RJH (talk) 21:11, 11 May 2009 (UTC)

Sun/Jupiter barycenter
Not sure what citation would be needed for the claim about the location of the Sun/Jupiter barycenter. It's just a matter of knowing the formulas, the equations, as shown in this section of the "Center of mass" article. See the examples in the table. On the far right at the bottom is the r1/R1 value - 1.07. So the barycenter is outside the surface of the Sun by 1.07 times its radius. That .07 figure above the radius represents the 7% used in this article. Here's a source for the equations needed, but the actual Sun/Jupiter mass ratio is not used there. What precisely does editor RJHall require? .`^) Painediss`cuss (^`.  02:37, 19 May 2009 (UTC)
 * PS. It might also be interesting to note that since Jupiter follows an elliptical track around the Sun, the position of the barycenter is sometimes closer to and sometimes farther away from the Sun.  Here's a quote from the CofM article...


 * The calculations above are based on the mean distance between the bodies and yield the mean value r1. But all celestial orbits are elliptical, and the distance between the bodies varies between the apses, depending on the eccentricity, e. Hence, the position of the barycenter varies too, and it is possible in some systems for the barycenter to be sometimes inside and sometimes outside the more massive body. This occurs where:


 * $${1 \over {1-e}} > {r_1 \over R_1} > {1 \over {1+e}}$$


 * Note that the Sun-Jupiter system, with eJupiter = 0.0484, just fails to qualify: 1.05 ≯ 1.07 > 0.954.


 * I would appreciate it if you could provide a source that satisfies the policy at Citing sources, so as to avoid claims of WP:NOR. Per the latter, a routine calculation is allowed, as long as a source is provided for the calculation. Usually what I do in that case is add a note showing the derivation (based on already cited values) and listing a source for the formula. But I think it would be preferable to have an authoritative source that shows the final result. Thank you.&mdash;RJH (talk) 17:13, 19 May 2009 (UTC)


 * Yes, I would also like a source that shows the final result. I looked for over an hour last night and was unable to locate one.  Are we on the right track in accepting the idea you have about using the math source I found coupled with an added note showing the derivation?  If so, then I must ask you to incorporate the information into the article, because I have no expertise in this.  I would like to learn how it's done, though.    .`^) Painediss`cuss (^`.   03:18, 20 May 2009 (UTC)


 * Okay, now I'm a bit confused. Did I miss something?  In the new reference you found, section 3.4 as cited states only that, "It is a curious coincidence that the barycenter of the Sun-Jupiter system lies almost exactly at the solar surface, . . ."  I am unable to find anything there that's more precise.  What have I missed?    .`^) Painediss`cuss (^`.   04:43, 21 May 2009 (UTC)
 * It gives a diameter of 1.5 million km for the orbit of the Sun around the barycenter with Jupiter, which is 7% more than the 1.4 million km diameter of the Sun.&mdash;RJH (talk) 16:46, 21 May 2009 (UTC)
 * Ah, thank you! If you're happy, RJ, then I'm happy.    .`^) Painediss`cuss (^`.   19:35, 22 May 2009 (UTC)
 * Thanks. I was hoping for a more consise reference, but that at least confirms the info.&mdash;RJH (talk) 17:24, 23 May 2009 (UTC)

Is there a grammar problem
in:"It is a gas giant with mass slightly less than one thousandth that of the Sun and two and a half times more massive than all of the other planets in our Solar System combined." ?It sounds funny.75.45.106.99 (talk) 01:04, 11 June 2009 (UTC)

Jupiter
i need info —Preceding unsigned comment added by 220.239.250.47 (talk) 07:26, 16 June 2009 (UTC)
 * That's kinda what the page is for.  Serendi pod ous  11:19, 22 June 2009 (UTC)

In fiction
The category Jupiter in fiction includes 62 articles. All that stuff should merit some mentioning in this article. It seems an arbitrary choice to include a good section on religion and nothing about fiction. --Ettrig (talk) 07:27, 11 July 2009 (UTC)
 * Jupiter's impact on culture goes so far beyond mere fiction that to merely mention fiction is to trivialise the issue. What about religion, history, poetry, philosophy, astrology?  Serendi pod ous  07:36, 11 July 2009 (UTC)
 * That is one person's view, yours. Who are we to disregard all those who wrote those 62 articles. --Ettrig (talk) 08:34, 11 July 2009 (UTC)
 * They are no longer being disregarded, Ettrig. The cat has been added to the article for those readers who are interested in planet Jupiter's utilization in fiction.  The article is getting a bit long, and this also must be considered when contemplating additions.  Also, I have checked, and there are no existing cats nor articles yet for the other specific possibilities mentioned by Serendipodous.  If interested, this may be an avenue to pursue?    .`^) Paine Ellsworthdiss`cuss (^`.   08:45, 11 July 2009 (UTC)
 * The article Jupiter in fiction covers the topic, but is badly undercited. It could be mentioned here using WP:SS, but I would urge that the main article on the topic be brought up to wikipedia standards first. Unsourced material can be challenged and removed. In this case, the material is so poorly cited that it may be removed mercilessly from this FA article in order to keep it up to the Featured article criteria standard.&mdash;RJH (talk) 18:49, 12 July 2009 (UTC)

Possible impact
There may have just been an asteroid or comet impact similar to the Shoemaker-Levy impacts. JCDenton2052 (talk) 05:06, 20 July 2009 (UTC)
 * Perhaps. But this article doesn't mention it yet, so it doesn't document a current event. Might need its own article over on Google News; will need more documentation before it comes here.  Serendi pod ous  06:40, 20 July 2009 (UTC)

I've added mention of the impact to the Jupiter main page now, as there are pictures of the impact site and corroboration by JPL. Violentbob (talk) 14:39, 20 July 2009 (UTC)

JPL confirms: http://www.jpl.nasa.gov/news/news.cfm?release=2009-112 Add info to the article. 63.245.144.68 (talk) 05:32, 21 July 2009 (UTC)

2009 Jupiter impact
As this is a recent event, I suppose I can understand why it has received an inordinate amount of coverage on this page; greater even than the more significance comet Shoemaker-Levy 9 impact. However, because it now has a separate article, I think it should be trimmed way back to a single sentence per WP:SS, and the redundant descriptions merged.&mdash;RJH (talk) 17:20, 24 July 2009 (UTC)


 * As to other impacts, I have added two sentences summarising a survey of historical records suggesting a possible 1690 impact. That could also be reduced to just one sentence.
 * That's an interesting addition. Thanks.&mdash;RJH (talk) 18:47, 27 July 2009 (UTC)


 * Meanwhile there is an interesting diagram of estimated comet impact rates at Jupiter and Saturn in a 2003 paper (Cratering rates in the outer Solar System, Icarus 2003, page 268, link). Their estimates have very wide error bars (for example 1 km comets impact Jupiter at a mean rate of once every 8 to 100 years). -84user (talk) 11:42, 26 July 2009 (UTC)
 * More impact observations at different latitudes may be interesting for comparison studies. Thanks.&mdash;RJH (talk) 18:47, 27 July 2009 (UTC)

Broken Source Link #102
Source #102 is a broken link, but it's summarized in other locations with information pertinent to the current article.

I've never edited a Wiki source before, so I just thought I'd mention the broken link here instead. Here's a location that can probably be used as an alternate source. —Preceding unsigned comment added by Jambeeno (talk • contribs) 12:34, 26 July 2009 (UTC)
 * Thank you for identifying the broken link. In the course of checking the secondary source, I found that a primary source is available. Thus I substituted that journal article instead of the news story. Thanks again.&mdash;RJH (talk) 18:43, 27 July 2009 (UTC)

Does it have a surface ??
I asked this in 'Neptune' as well. All of the entries for the Jovian Planets neglect to say whether they have a surface. Why isn't this question EVER addressed ?? Talk of Metallic Hydrogen and what not ? It still doesn't sound like something that has a surface that can be landed on. Why doesn't the article explain why Jovian Planets are classified as planets - and not a tiny core with a shit load funny coloured clouds ?
 * Jupiter's surface is officially designated as the point at which atmospheric pressure = 1 bar. It is mentioned in the Atmosphere of Jupiter article.  Serendi pod ous  14:52, 2 August 2009 (UTC)
 * I suspect it might not have a well-defined solid surface below the gas layers, even though it may definitely be solid further down. I.e. for all we know it could be a graded transition with steadily increasing viscosity. See the phase transition article, for example.&mdash;RJH (talk) 17:20, 2 August 2009 (UTC)

Planet's size
This article says the following:

"Jupiter is 2.5 times more massive than all the other planets in our Solar System combined"

This wording is incorrect, it should say "..2.5 times as massive as...".

I can't edit this myself because I'm not a 'confirmed' member. —Preceding unsigned comment added by 76.91.100.103 (talk) 19:26, 16 August 2009 (UTC)

...also just noticed the wording is used twice in the article. Once in the first paragraph, and again under the 'Mass' subheading. —Preceding unsigned comment added by 76.91.100.103 (talk) 19:33, 16 August 2009 (UTC)
 * Good point. Fixed. Also, for future reference, new topics go at the bottom of the page, not the top.  Serendi pod ous  06:43, 17 August 2009 (UTC)

The word mass appears in the first sentence.
Should it be linked?Rich (talk) 23:40, 21 August 2009 (UTC)
 * Linked. Also corrected a grammar flub.  Serendi pod ous  02:23, 22 August 2009 (UTC)

Great Red Spot
In the section on storms, it states that the Great Red Spot is permanent. In numerous articles online, notably this one, it is stated that the spot is actually shrinking. —Preceding unsigned comment added by 198.73.131.132 (talk) 15:20, 3 September 2009 (UTC)
 * It is shrinking, but it is still Jupiter's most visible feature.  Serendi pod ous  18:36, 3 September 2009 (UTC)
 * I don't know that shrinking would necessarily mean it is going away. It may just be an intermediate term variation and it could grow back again later.&mdash;RJH (talk) 20:04, 3 September 2009 (UTC)

Should Jupiter mass be merged with this article?

 * The following discussion is archived. Please do not modify it. Subsequent comments should be made in a new section.

Jupiter mass deals with a notable unit of measurement common in extrasolar planet research, but it only really contains one or two sentences of useful information. I've added a reference to the Jupiter mass unit into Jupiter (where I think it should be anyway), but there has always been some resistance to my merging it completely. Is the topic notable enough to sustain an article of only a few sentences?  Serendi pod ous  07:01, 5 September 2009 (UTC)


 * A Jupiter mass is used in the def. of Exoplanet and on the Brown dwarf page, so I agree that there's no need for a separate article on Jupiter mass.
 * &mdash;  .`^) Paine Ellsworthdiss`cuss (^`.   07:15, 5 September 2009 (UTC)


 * Jupiter mass deserves a separate article as this mass unit is commonly used to measure the masses of extrasolar planets and brown dwarfs, and is linked to from many of our articles on individual extrasolar planets (e.g., WASP-11b.) So, we need to explain what it is.  Merging into Jupiter is a step for the worse as it dumps the reader into the middle of a large sea of text, most of which (e.g., "its barycenter with the Sun actually lies above the Sun's surface...Although this planet dwarfs the Earth (with a diameter 11 times as great) it is considerably less dense...") is relevant to the planet but not to the mass unit.  It is better to have a separate, focussed article on the mass unit.
 * As an aside, I do not understand the comment of User:Paine Ellsworth above. Jupiter mass is indeed mentioned on the pages he describes, but how does that justify its merge?
 * Spacepotato (talk) 17:33, 5 September 2009 (UTC)


 * Resistance is based on common sense. What reasons can be given, other than Jupiter mass being a stub, for a unit of measurement to be merged into an article about a planet? HarryAlffa (talk) 17:23, 18 September 2009 (UTC)
 * The fact that not only is it a stub, but it has never been anything but a stub, and is unlikely to ever be anything more than a stub.  Serendi pod ous  17:29, 18 September 2009 (UTC)
 * Resistance is based on common sense.
 * Other than Jupiter mass being a stub, what reasons can be given for a unit of measurement to be merged into an article about a planet? HarryAlffa (talk) 17:38, 18 September 2009 (UTC)


 * Stub status is not, in and of itself, a reason to merge. WP:STUB: "Note that if a small article has little properly sourced information, or if its subject has no inherent notability, it may be deleted or be merged into another relevant article."  Neither criterion is present in this case. TJRC (talk) 19:02, 18 September 2009 (UTC)
 * Actually why is Jupiter mass labelled a stub? Is it just because it doesn't look complete? When in fact it is? Or is it? How much, quantity that is, can you say really about any of Earth mass, Lunar mass, Solar mass? If they are complete should the stub be removed? HarryAlffa (talk) 16:52, 19 September 2009 (UTC)

Perhaps, if it might be possible to be constructive with you for once, it could be merged with another article?  Serendi pod ous  18:43, 18 September 2009 (UTC)
 * Well I guess this is what makes horse races exciting. My first thought is that Jupiter mass should be a separate article, even though it is just a stub.  Many exoplanets link to the definition and I think the reader should get a concise definition that does not run off on potentially confusing tangents.  There is also an Earth mass stub. -- Kheider (talk) 18:48, 18 September 2009 (UTC)

Serendipodous attempted to force this through before on 18 September, 2008. A couple of days later User:Spacepotato reverted him. I can find no discussion of the merge in either article talk pages.

Serendipodous again force-merged this on 2 September, 2009 with no discussion on either talk page, Spacepotato reverted him later that day.

This discussion section didn't appear until 5 September, 2009.


 * Oppose. The Jupiter mass article is about the unit, not the planet.  It's better served by its own article.  If someone wants to know about the unit, he shouldn't have to go through another article looking for a small section that describes it.  Similarly, I wouldn't expect Astronomical unit, an article on a unit of measure, to be merged into Earth's Orbit, an article on the thing from which the unit is derived. TJRC (talk) 18:57, 18 September 2009 (UTC)
 * There are several astronomical units that are widely used and have their own article: astronomical unit, solar mass, solar radius, solar luminosity. Although it would seem common sense to merge, I think the term "Jupiter mass" is so widely used now that a separate article seems more appropriate. Sorry Serendipodous. Perhaps the article could discuss the mass in terms of planetary detection and stellar system formation? I'll see if I can dig up some material.&mdash;RJH (talk) 20:25, 18 September 2009 (UTC)
 * Oppose this is a widely used unit of measure. An article should exist on it. We have an article on solar mass. Even if it were to be merged, it should not be merged here, since this article is not about units of measurement. 76.66.196.139 (talk) 05:39, 19 September 2009 (UTC)
 * Oppose it is entirely illogical to merge a unit of measurement article with a planet article. Earth mass with Earth? Lunar mass with Moon? Solar mass with Sun? No. HarryAlffa (talk) 16:49, 19 September 2009 (UTC)
 * Oppose. What is needed, if there are stub articles proliferating everywhere, is a Mass units of planetary systems or some such article. Nice and useful for the extrasolar planet work: things are frequently referred to in units of M_Earth and M_Jupiter, along with (more infrequently) M_Neptune. (Someone needs to delete the invented M_Moon article, incidentally). Could possibly even add in the radius usage as well, for a more cohesive article: Measurement units of planetary systems. Then the fun discussion over how different groups use different R_Jupiter values can be discussed, etc... Iridia (talk) 00:05, 21 September 2009 (UTC)
 * I agree with Iridia that Jupiter mass (or a combined Jupiter/Earth/Neptune measurement article) would benefit from also covering radius measurements. This is why I expanded Jupiter mass to show an image of the rough relative sizes of Jupiter-Gliese 229B -Teide 1, mentioned COROT-1b and added the radius of a brown dwarf.  I also think the measurement Lunar mass is NOT common and perhaps should be deleted/merged. -- Kheider (talk) 03:31, 21 September 2009 (UTC)
 * Ok, well, I just realised HarryAlffa has started modifying Astronomical system of units to incorporate information, presumably in preparation for merging things there. Further discussion there, perhaps? Iridia (talk) 00:18, 22 September 2009 (UTC)
 * It's not clear to me that a Jupiter mass is an IAU standard. I didn't see it listed in the citation on the Astronomical system of units article. So a merge may not be appropriate unless the scope is expanded.&mdash;RJH (talk) 19:40, 22 September 2009 (UTC)

Alright, we have Physchim62 and TStein at Talk:Astronomical system of units, and here at Talk:Jupiter we have Kheider and myself in clear support of a merged planetary mass article, to merge Jupiter mass and Earth mass. I would say this is probably sufficient consensus: are there any other suggestions, or any objections? Iridia (talk) 00:37, 23 September 2009 (UTC)
 * The only objection I have is that this discussion has actually spurred editors to expand the Jupiter mass article out of stubhood, though it is still of "mergeable" size. Should solar mass be merged with Astronomical system of units?  Serendi pod ous  08:14, 23 September 2009 (UTC)
 * Technically, I was supporting adding radius info to the mass articles. As far as the mergers, I am still more-or-less sitting on the fence. -- Kheider (talk) 08:45, 23 September 2009 (UTC)
 * Physchim62 has made a nice start-class article at planetary mass. Iridia (talk) 02:20, 29 September 2009 (UTC)
 * I don't think there would be any problems in merging the recent material at Jupiter mass into planetary mass, as the prose at Jupiter mass seems to refer more to planetary mass in general rather than to he mass of Jupiter in particular. I haven't done it yet because I am waiting to see if there are any more objections, and using the time to do some separate tweaks on the planetary mass article. Adding in radius as well is more than possible, although it would take more work: I have sets of planetary radii, but we would also need some explanation of how they are obtained and what are the uncertainties. For most asteroids, the only estimate we have of the mass is a measured radius and an assumed density. Physchim62 (talk) 09:30, 29 September 2009 (UTC)


 * The above discussion is preserved as an archive. Please do not modify it. Subsequent comments should be made in a new section.