|Wikipedia CD Selection|
|WikiProject Solar System||(Rated C-class, Top-importance)|
|Giant planet has been listed as a level-4 vital article in Science. If you can improve it, please do. This article has been rated as C-Class.|
|WikiProject Astronomy / Astronomical objects||(Rated C-class, High-importance)|
- 1 modified paragraph
- 2 Merge with Sudarsky classification system
- 3 Liquid Helium???
- 4 Mass gap?
- 5 Floating cities
- 6 To scale or not to scale?
- 7 Moons
- 8 Ice Giant
- 9 Uranus and Neptune
- 10 What causes the atmospheric banding exactly?
- 11 Discovery
- 12 Gas planet size
- 13 The Color Spectrum Seen in the Jovian Planets
- 14 Question
- 15 Ice Giants vs. Gas Giants, Again
- 16 Super??
- 17 Redundancies in the "See Also" section
- 18 Should Jovian be capitalized?
- 19 Requested move I
- 20 Ice Giants and "molten ice"
- 21 Requested move II
- 22 Ice giants as subset of gas giants
- 23 Requested move III
I modified this paragraph beyond recognition:
Many of the extrasolar planets which have been discovered have masses of several times Jupiter's mass, and on the basis of this it has been suggested that these may be gas giants. However, it is important to note that the detection techniques that have been used to identify extrasolar planets so far (detecting doppler shift in the star's spectrum due to the wobble induced by the planet's orbit) are much more adept at detecting giant planets than smaller ones and therefore this sample may be biased. In addition, with a few exceptions, the actual composition and structure of extrasolar planets have not been observed and many of the extrasolar planets are much closer to their parent stars and hence much hotter than gas giants in the solar system, making it possible that some of those planets are a type not observed in the solar system.
I think the new version is better, but ymmv. Mark Foskey
This article could be clearer about the difference between gas giants and brown dwarves. The latter article says: "Density is a clear giveaway. Brown dwarfs are all about the same radius and volume; so anything that size with over 10 Jupiter masses is unlikely to be a planet" while this article says gas giants are planets and can exist up to ~70 Jupiter masses. Horatio 12:09, 30 July 2005 (UTC)
Merge with Sudarsky classification system
The article has gotten long and I do not want to jump in while it is changing in so many places, but I feel that this statement: "the name is defensible because their compositions are dominated by hydrogen and helium, which are gases in the outer solar system when not under pressure." is misleading. Helium will be in gaseous state anywhere in these planets, I believe, because it has to be cooled so much to liquefy. I also thought hydrogen could be in a metalllic state in Jupiter (helping explain the magnetic field). So I think "gas giants" refers mainly to the paucity of rock. Carrionluggage 17:43, 10 February 2006 (UTC)
- Hi, I created that sentence, but I was just copyediting for clarity and have no scientific background, so if you think it's wrong you should change it. The Singing Badger 18:34, 10 February 2006 (UTC)
OK - I fixed it so it is correct, but the section is much too long now and refers to "misnomer" or a synonymous phraseology twice. It might have been OK as it was before - do not know why S.B. changed it. By the way, I linked in a page that briefly discusses "critical point" because the Wikipedia page Phases_of_matter containing critical phenomena is quite verbose, with too much in it, and the phase diagram showing a critical point is way down the page.Carrionluggage 04:53, 11 February 2006 (UTC)
"Interestingly there appears to be a mass gap between the heaviest gas giant planets detected (about 10 times the mass of Jupiter) and the lightest red dwarfs." - is there? The missing objects would presumably be brown dwarfs, of which we now know a fair few. And there doesn't seem to be much of a gap between the brown dwarfs and large planets either - OTS 44 and Cha 110913-773444 seem to bridge the gap between planets and brown dwarfs. Am I missing something or is the article statement now outdated? Chaos syndrome 22:44, 13 March 2006 (UTC)
To scale or not to scale?
There are two pictures in the article, one "to scale" the other "not to scale". Yet both have pretty much the same relative sizes of the 4 planets. Maybe they are both "to scale"?--345Kai 22:09, 24 August 2006 (UTC)
I noticed there is a small comment about moons in the article, but perhaps we should elaborate. Maybe we should discuss the debris cloud that surrounds the gas giants when they are being formed and how the cloud matter can build moons and rings.
The scientific community has adopted the term "ice giant" to describe Uranus and Neptune, since they differ in both composition and evolution from their fellow giant planets Jupiter and Saturn. This term is quickly gaining common usage; a separate article should be established for Ice Giant, preferably written by someone within the astrophysics field, and the link for such should no longer redirect to this page.PJtP 21:58, 18 January 2007 (UTC)
- If this article is renamed giant planet, and gas giant and ice giant are broken out as separate articles... 188.8.131.52 22:47, 25 April 2007 (UTC)
Uranus and Neptune
Is Uranus really the most foul smelling gas giant?Astroman1111 11:52, 11 August 2007 (UTC)
What causes the atmospheric banding exactly?
I have ascribed this to tidal force for the time being - rapid rotation does not explain it fully. It makes sense given that Jupiter has extremely turbulent bands (closest to the sun) while Uranus has very weak banding. I do not understand exactly how tidal forces can account for this at the mechanical level, but it seems reasonable. Comment please, and perhaps we can get some citations for it.--ChrisJMoor 00:50, 16 September 2007 (UTC)
- Thank you for trying to improve Wikipedia. Unfortunately, ascribing the banding on Jupiter to tidal forces based on it seeming reasonable is original research. The bands are caused by a combination of the Coriolis force and convection, the same mechanism that produces the jet streams and trade winds on Earth. Neitherday 05:02, 16 September 2007 (UTC)
Asking for a bit of info I've never been able to find anywhere: When was Jupiter found to be a gaseous planet? this page was created by marysa--184.108.40.206 22:18, 24 October 2007 (UTC)
Gas planet size
Technical question: Allowing for variations in gas-mixture composition (ie relative quantities of hydrogen, helium, methane "and all other possible components") what is the smallest size a gas giant could be and be persistant on an astronomical scale? Jackiespeel (talk) 17:16, 29 July 2008 (UTC)
- Do you mean geometrical size, or mass of a planet? Sometimes people say "size", but actually mean mass. Ruslik (talk) 18:36, 29 July 2008 (UTC)
- You need to consider Ruslik's question to find the answer. Neptune, for example, is only about 31 times smaller in diameter, but 16,000 times smaller in volume, and 19,000 times smaller in mass (weight) than the Sun. Also, your question belongs at the answer desk, not on an article's Talk page. David Spector (talk) 13:03, 31 May 2010 (UTC)
The Color Spectrum Seen in the Jovian Planets
Has anyone ever noticed that the color of the Jovian planets rougly matches the color spectrum: 1. Red - Jupiter is somewhat reddish/orangish/brownish, especially towards the middle. 2. Yellow - Saturn is yellowish/tanish. 3. Green - Uranus is greenish-blue. 4. Blue - Neptune is deep blue.
- But even if you could get fusion started (with a giant much much much more massive than Jupiter), it would turn into a star, not blow up.
- There's a reference desk to ask questions like this. kwami (talk) 20:58, 24 October 2008 (UTC)
Ice Giants vs. Gas Giants, Again
I notice that somebody was pointing out this distinction well over a year ago. It's true -- Uranus and Neptune are not currently regarded within the astronomical community as gas giants. They are ice giants. Only Jupiter and Saturn, among the 8 Solar planets, are true gas giants. The distinction between Jupiter-type planets (gas giants) and Neptune-type planets (ice giants) is regularly made in the literature on extrasolar planets. I see the same two possibilities that were suggested previously: 1. Rename this article "giant planets" and separate it into two sections, one for gas giants and one for ice giants; or 2. Limit this article to true gas giants, and create a new article about ice giants. Option 1 would be easier, but it would also be less scientific, because, as I'm saying, planetary astronomers no longer lump the four Solar System giants into one category. What is the chain of decision-making here?Thuvan Dihn (talk) 23:48, 30 November 2008 (UTC)
Two years have now passed since User:PJtP pointed out that Uranus and Neptune are no longer regarded as "gas giant planets." I just did a little research to back up this claim.
- In an article in the October 1999 issue of Science, Tristan Guillot was already employing the distinction gas giant/ice giant in his discussion of the Solar System's four giant planets (T. Guillot, "Interiors of Giant Planets Inside and Outside the Solar System," Science, 1999: vol. 286, pages 72-76). Jupiter and Saturn are gas giants; Uranus and Neptune are ice giants.
- A search of the Smithsonian/NASA Astrophysics Data System (query form at http://adsabs.harvard.edu/abstract_service.html), using the keyword "gas giant planet" and limited to the years 2007 to 2009, yields 135 results. In all 135 cases, "gas giant planet" refers to Jupiter, Saturn, or an extrasolar planet of comparable or greater mass. "Ice giant planet" refers to Neptune, Uranus, or an extrasolar planet of comparable mass.
Is it important for a scientific article in Wikipedia to conform with current scientific research? If so, Wikipedia's handling of giant planets needs a major overhaul. Thuvan Dihn (talk) 22:24, 12 January 2009 (UTC)
- This is now under consideration, see #Requested move I -- 220.127.116.11 (talk) 14:44, 20 November 2011 (UTC)
Superjovian planet and kin redirects here but the string "super" doesn't occur in the article. I cannot remember exactly where or what, but I think there is a definition (somewhere) of what constitutes a superjovian as opposed to jovian. It should then be noted that the maximum radius (and hence volume) of a superjovian approx equals that of Jupiter, with the exception of hot jupiters, whose atms are heated so that they inflate. ... said: Rursus (bork²) 09:08, 22 April 2009 (UTC)
- There was something about superjovians/superplanets/supergiant planets being more massive than the mass of the planet with the largest volume possible for a cold planet (roughly the size and mass of Jupiter)  ... more massive planets being smaller than this most large cold planet. PDF (p126). According to PDF (section4) the limit is 500 M⊕. The calculations are based on the 1969 paper. 18.104.22.168 (talk) 00:02, 18 February 2011 (UTC)
Redundancies in the "See Also" section
I don't know if anybody's noticed, but the first two items in the See Also section link to the exact same place. Specifically, "Appearance of extrasolar planets" and "Sudarsky extrasolar planet classification" both link to "Sudarsky extrasolar planet classification." Since the Sudarsky extrasolar planet classification is simply a way to classify the appearance of extrasolar planets, I would suggest the "Appearance" link be removed. 22.214.171.124 (talk) 11:13, 15 May 2010 (UTC)
Should Jovian be capitalized?
I'm under the impression that "jovian" (lowercase) can refer to any gas planets, while "Jovian" (uppercase) usually refers specifically to Jupiter and its system of moons. Jovian, when used to mention all gas giants, should be lowercase in the article here much in the same way terrestrial, when referring to rocky planets, is lowercase in the same manner. Would I be out of place to edit the article's mentions of the word "jovian" when pertaining to gas giants and not the Jovian system?126.96.36.199 (talk) 06:46, 8 November 2011 (UTC)
Requested move I
Ice Giants and "molten ice"
The following sentence caught my eye: "...Uranus and Neptune which are sometimes called ice giants, as they are mostly composed of water, ammonia, and methane molten ices." What is a "molten ice"? The only other mentions of molten ice I can find on Wikipedia refer to fiction. Ischaldirh (talk) 23:18, 4 March 2012 (UTC)Ischaldirh
Requested move II
Ice giants as subset of gas giants
From the Neptune article, which is currently a featured article. Astronomers sometimes categorise Uranus and Neptune as "ice giants" in order to emphasise these distinctions. Neptune and Uranus are often considered a sub-class of gas giant termed "ice giants", due to their smaller size and higher concentrations of volatiles relative to Jupiter and Saturn. Note these sources do not exclude Neptune from the category of gas giant, although they suggest that ice giant as a sub-category.Limefrost Spiral (talk) 01:02, 30 January 2013 (UTC)
- The term is evolving and I can see it both ways. Can we find a wording that leaves it somewhat open? Definitions for a planet, dwarf planet, meteoroid, or gas giant should have some wiggle room. -- Kheider (talk) 01:30, 30 January 2013 (UTC)
- More fuzziness. Are super-Earths really mini-Neptunes? (Royal Astronomical Society 04 February 2013) -- Kheider (talk) 22:51, 4 February 2013 (UTC)