Talk:Jupiter/Archive 1

message: The overview image is not accurate at all:  http://en.wikipedia.org/wiki/Image:Jupiter-Earth-Spot_comparison.jpg  You can visually tell it would take more than 10 or 11 of those Earths to make the diameter of Jupiter.  I re-created the image from the same two source images, and I uploaded it, but I am unsure of how to replace this image.  I am unsure how to maintain the same copyright information.  Anyone willing to help? JasonAD 17:39, 6 May 2006 (UTC)
thread_title: Overview Image

message: The section with the above title is out of date as it doesn't refer to the many new moons discovered in the last ten years. I'm not sure if the simple division of four groups is still tenable. Someone who knows a bit more about the subject should check this section and correct it. The Singing Badger 21:25, 7 Oct 2004 (UTC)
replies: text: Was vandalism, been reverted. Femto 18:34, 9 January 2006 (UTC)
thread_title: Classification of Jupiter's moons

message: The following line doesn't seem to make any sense:
It has been known since prehistoric times.
How is it possible to know what humans knew before recorded history? If they didn't write it down, it's not there for us to read!
:As far back as historical records go, Jupiter has been recorded as being known. Therefore, it makes sense that it msut have been known before records began.
Another oddity: "Jupiter has a very large and powerful magnetosphere. In fact, if you could see Jupiter's magnetic field from Earth, it would appear five times as large as the full moon in the sky despite being so much farther away." 
What does it mean? Magnetic fields aren't blobs in the sky - how can you talk about how big they would be 'if you could see them'? Theres just 1 magnetic field and it's everywhere!! This comment seems to make no sense!
:I don't get that one either.  Where does Jupiter's magnetic field end?  Where other magnetic fields drown it out?  --Doradus 19:33, 27 April 2006 (UTC)
replies: text: The magnetosphere defines the space within which the magnetic field generated by the planet dominates over that carried by the Solar Wind, known as the Interplanetary Magnetic Field. Magnetospheres protect planets against the Solar wind and can be measured. Satellites such as Cluster around Earth and Cassini around Saturn carry magnetometres which can measure the changes in field strength. Look at related articles on wiki about all this stuff. Other magnetic fields drown out Jupiter's at the Magnetopause. The magentosphere looks a bit like a windsock, with a tail extending away from the sun like the ion tail of a comet. --MilleauRekiir 21:51, 8 May 2006 (UTC)
thread_title:  huh? 

message: I've taken some info from NASA's text at http://vesuvius.jsc.nasa.gov/er/seh/jupiter.html --GeneralPatton 23:58, 26 Jul 2004 (UTC)
thread_title: PD info

message: The full disc image of the planet at the top of the page is a bit ....well.....sucky. The vidicon tubes of the 70's are simply not capable of showing the atmosphere in all its majetsy. I think this  image from cassini's ccd is jaw droppingly good ....but it's not a full disc. What do we think? Leave image as is, or replace?--Deglr6328 05:57, 28 Mar 2005 (UTC)
thread_title: intro pic

message: I've never been thrilled with this statement:
:Jupiter is ... so massive that its barycenter with the Sun actually lies above the Sun's surface
The distance of the barycenter is proportional to mass times distance, so it would be equally valid to say that Jupiter is so distant that its barycenter is above the Sun's surface.  In other words, the barycenter's position is not the least bit significant in getting a feel for a planet's impact on the Sun.  For instance, Mercury's barycenter would also be above the Sun's surface if Mercury were in the Oort cloud.  --Doradus 16:17, Apr 27, 2005 (UTC)
:I agree, the statement doesn't really seem relevant and certainly should not be in the 'Overview' section. 81.98.47.57 15:46, 2 November 2006 (UTC)
thread_title:  Barycenter 

message: This statement seems out of place, especially the part after the semi colon which has nothing to do with Jupiter.  I think it should be left to the reader to click on the Galileo link to find out more about Galileo.  Thoughts?  Jryden 16:24, 25 July 2005 (UTC)
thread_title:  Odd statement 

message: Do we know why jupiter spins so fast ?
:The simple answer is "because it can". And that's not as facetious as it reads. If you start with a blob of matter (mostly hydrogen gas), it is bound to have some rotation, even if almost negligible (differential revolution about the galaxy's centre is bound to induce a slight rotation, for example). As the blob contracts, the rotation increases as rapidly as the radius shrinks. So what is unusual is when an object does not spin, such as Venus. Urhixidur 14:18, 2005 August 20 (UTC)
::As for why it spins so much faster than the other planets, and than the sun, perhaps this is due to the enormous mass of planetesimals and debris that it's swept up, especially early on? This was a much larger amount than any other planet. The orbital momentum of all the impacting objects would have affected to Jupiter's rotation. But I would intuitively expect the effect to slow down Jupiter's rotation, since objects inside Jupiter's orbit would be moving faster than Jupiter but against its rotation, while those outside its orbit would be moving with its rotation, but slower than Jupiter; and objects hurtling in from the outer Solar system could strike either side of the planet and therefore should have no net effect. But by that same principal I'd expect the planets to rotate clockwise, so I'm obviously missing something. (Unless each planet formed from a small contracting nebula like the sun, and sped up as it contracted? But that's not the current model.) Maybe someone who knows what they're talking about can answer this 3-month-old question? kwami 23:46, 18 November 2005 (UTC)
thread_title:  Jupiters rotation 

message: Does that follow some particular philosphy, guideline, or practice ?
:No, it's just an oversight. I've added a little summary and wikilink to Trojan asteroids. I don't think they're technically considered moons, but I don't think they deserve a whole section to themselves either. --Dhartung | Talk 20:29, 19 August 2005 (UTC)
replies: text:  I put them in their own section for now because I don't think they belong with the moons. Maybe we need a section on 'Jupiter's gravitational effects on the solar system' to cover the Trojans as well as all the comets that get deflected by it? The Singing Badger 21:04, 19 August 2005 (UTC)
replies: text:  On second thought that's not so bad (I just hate articles with endlessly proliferating top-level sections, it usually speaks to poor organization). Since we know that Saturn and Earth have Trojans, now, it's almost like a separate standard category. --Dhartung | Talk 03:01, 20 August 2005 (UTC)
thread_title:  No Mention / Link of Trojans on this page 

message: I've just updated the sidereal period of Jupiter (and will shortly do the same to the remaining planets) to be consistent with the JPL data set. The change has also slighlty changed the orbital speed and synodic period entries, naturally.
First off, the value now in there (4,333.2867 d) is for the mean orbital elements. It was retro-computed from the well-established semi-major axis (and the JPL value for the AU), the JPL value for the solar GM product (avoiding the nastiness related to JPL's value for G being different from the most recent CODATA one, I think), and takes into account the Sun/Jupiter mass ratio. I used the JPL-supplied value for Jupiter's mass, which is slightly incoherent with JPL's value for the Sun/Jupiter-system ratio; such is life.
The "barycentric correction" is most prominent with Jupiter, as one would expect:
\omega^2 = \frac {GM} {R^3(1+m/M)^2} = \frac {GM(1+m/M)} {a^3} where M is the Sun's mass and m is the secondary's mass (in this case Jupiter). \omega is, of course, the angular frequency. Note that the semi-major axis is for the heliocentric orbit.
The value reported for Jupiter's sidereal period by other sources (such as IMCCÉ, NSSDC, etc.) is 4332.589 d, still different from the JPL-computed 4333.287
d. Maybe the former value is for the instantaneous orbit at epoch?
Urhixidur 20:54, 11 October 2005 (UTC)
thread_title:  Revising the sidereal period 

message: When astronimers are taking into account Jupiter's massive size, are they recording just the rocky center, or the hydrogen liquid/gasses that surround it as well? If they are including the liquids/gasses, would Jupiter still be considered so large if they were to only measure the rocky center? Thanks! —The preceding unsigned comment was added by 68.81.182.9 (talk • contribs) 2005-11-07 00:09:46.
:I'm sure the vast majority of calculations (for example, trying to put satellites in orbit around it) take into account both the solid core and the liquids and gasses. Jupiter would not be nearly as large (or massive) without its outer layers. —HorsePunchKid→龜 05:27, 7 November 2005 (UTC)
replies: text: Compared to the planet (318 Earth's mass), Jupiter's core is really tiny, maybe 15-20 Earth's mass -- if the core even exists! As HorsePunchKid implied, every layer of Jupiter is taken into account when its mass is measured.--Jyril 17:37, 7 November 2005 (UTC)
replies: text: I believe the radius and volume estimates are to the visible cloud tops (the "surface" you see in the Cassini images). kwami 08:31, 15 December 2005 (UTC)

text:  The 'surface' of Jupiter for the sake of radii and other measurements is the point at which the atmospheric pressure falls to that on the surface of Earth, the 'one atmosphere' level where atmosphere is a measure of pressure --MilleauRekiir 21:57, 8 May 2006 (UTC)
thread_title:  Quick Question 

message: How did the Romans know that Jupiter was the largest planet, naming it after the king of their Gods?
--Bannus 14:08, 18 November 2005 (UTC)
replies: text: Yeah, you'd think it would be Venus. But I doubt they thought Jupiter was larger. Perhaps because it's the brightest regular planet? The Morning Star/Evening Star may be brighter, but isn't as constant, and it would have taken a while even to recognize that they're the same object. kwami 23:54, 18 November 2005 (UTC)

text: I think it's because the slower planets seem older and more majestic.  Hence, Saturn (the slowest known planet) was named after a titan, and titans are older than the Gods.  Jupiter was naturally named after the king of the gods.  Mars is red, evoking blood, hence the god of war.  Venus is a natural "opposite" to Mars.  Mercury orbits the fastest, so it's named after the super-fast messenger god.  --Doradus 02:03, 28 April 2006 (UTC)
thread_title:  Romans' Name? 

message: The "Io, Richard, Europa, and Ganymede" on the section on Jupiter's satellites is probably vandalism. I did not find Richard on the list of Jupiter's satellites. Rintrah 08:19, 26 November 2005 (UTC)
thread_title: Problem

message: Dear NASA,
Why not send weather satellites to Jupiter?  Then we could put them on TV, for a Jupiter Weather Channel akin to the current (Earth) Weather Channel.  I'm sure lots of people would be interested to see up-to-the-minute pictures and video of Jupiter.  oneismany 11:44, 29 November 2005 (UTC)
replies: text: What? There's no point in sending a satellite to extraterrestrial planets?  Helloooo!  How about measuring the distances to the stars and galaxies, the most fundamental task of astrophysics?  Currently our best way of measuring the parallax of nearby stars against background stars is to measure at the perihelion and at the aphelion of Earth's orbit!  But that's only a distance of 2 AU!  So why should we only use Earth-orbiting telescopes?  Jupiter, for example is 5 AU away from the Sun!  The closest we could ever come to Juputer is 4 AU!  With telescopes located at the planets, and the asteroids, we could vastly improve our ability to measure the distances to stars.  I don't know if it would help to measure the distance to galaxies (would telescopes in the Oort cloud even be far enough to measure parallax for a nearby galaxy?), but hell, we can do better than 2 AU! oneismany 13:56, 25 January 2006 (UTC)

text: And anyway, who says people don't want to see the planets close up?  We've been looking at them by telescopes and other means for thousands of years, but we don't want to see them close up?  oneismany 13:56, 25 January 2006 (UTC)
replies: text: Please note that this page is here to discuss the Wikipedia article on Jupiter, not to discuss Jupiter in general.  It's not a blog, and (interesting as it may be) it's not the place for an open letter to NASA.  --Doradus 02:41, 28 April 2006 (UTC)
thread_title: Dear NASA

message: I removed the huge table of (basically incomprehensible) numbers from the article. It is a highly specialized dataset in which only a very few readers could have an interest (certainly none of the casual ones). Wikipedia isn't just an infodump. —ZorkFox 03:07, 28 December 2005 (UTC)
replies: text: Certainly it doesn't belong to an encyclopedic article. However, occultation data is valuable information and I recommend adding it to the Wikisource.--Jyril 11:00, 28 December 2005 (UTC)
thread_title:  List of occulted stars 

message: --From the intro "some have described the solar system as consisting of the Sun, Jupiter, and assorted debris". Does this really make any sense? Saturn is 9.5 times the size of earth, while Jupiter is 11.2, hardly debris by comparison. I think this statement gives the wrong impression about the relative sizes of the planets. Just my two cents... --Jleon 20:56, 1 February 2006 (UTC)
replies: text: I think the problem comes from your use of the word "size" which is ambiguous in this case.  True, Jupiter's diameter is 11.2 times that of Earth, but it's mass is 1,321.3 times that of Earth.  The descriptions of the other planets as debris is perhaps in the nature of hyperbole, but I find it an amusing paraphrasing of what is possibly the best-known work of fiction focusing on Jupiter (that is, 2001: A Space Odyssey and its sequels), and as such find it rather appropriate. —ZorkFox 04:51, 2 February 2006 (UTC)
replies: text: The quote is from Asimov's essay "By Jove!", which can be found in the collections View From a Height and Asimov on Astronomy.  The actual quote is "four planets, plus debris". --Johnny Pez 06:32, 27 September 2006 (UTC)
thread_title:  Other gas giants assorted debris?  

message: Is it really necessary to introduce Vedic Astrology into this article? --DannyZ 07:27, 5 February 2006 (UTC)
replies: text: Is there a reason not to?  --Doradus 17:00, 19 May 2006 (UTC)
replies: text: No and yes. Having a short mention in the Historical observations section is only balanced. Anything beyond that should go into Jupiter in astrology from the See also section. Femto 17:49, 19 May 2006 (UTC)
thread_title:  Vedic Astrology? 

message: Jupiter now has two red spots.  See this. — Hurricane Devon ( Talk ) 18:03, 4 March 2006 (UTC)
thread_title:  Red, Jr. 

message: why is the jupiter symbol  appearing way below the end of the page for me? the same effect can be seen on each of jupiter's moon's pages (that i checked, anyway), such as Adrastea (moon) - in fact, on that page, the the link to the image mysteriously isn't even in the code! it might be a wacky template thing, but i couldn't figure it out... Mlm42 15:10, 15 March 2006 (UTC)
replies: text: So i figured it out after all.. it's the Template:Jupiter that's doing it.. event on the template page the image is in a wonky place off the bottom of the screen.. and after many attempts, i don't see how to fix it, short of removing the image.. Mlm42 17:28, 16 March 2006 (UTC)
thread_title:  jupiter symbol appearing way below page 

message: Do you think it would be a good idea to add the minimum, maximum, and average distance between Jupiter and Earth. --Ephant 00:22, 5 April 2006 (UTC)
thread_title:  Distance between Earth and Jupiter 

message: This line is in the Jupiter entry:
"Jupiter is usually the fourth brightest object in the sky (after the Sun, the Moon and Venus); however at times Mars appears brighter than Jupiter."
In the Mars entry we have:
"Mars can be seen from Earth by the naked eye with a brightness of up to -2.9 magnitude, only surpassed by Venus, the Moon and the Sun."
The two seem to contradict each other.
Anyone know which is correct? Ajkgordon 17:03, 29 May 2006 (UTC)
replies: text: Both are correct, in context.  The magnitude of -2.9 is the highest Mars is seen as, which would make it brighter than Jupiter at that time.  The sentence is stating that Mars' brightest magnitude is "only surpassed by Venus, the Moon and the Sun."  The sentences do not contradict. - CobaltBlueTony 17:02, 30 May 2006 (UTC)
replies: text: Agreed. Ajkgordon 13:51, 31 May 2006 (UTC)
replies: text: "Brightest object in the sky" statements for the planets, the sun and the moon tend to be judged at their brightest, so either the statement about Mars or Jupiter is wrong. I can't find a source for the brightness of Jupiter. -- JamesHoadley 12:38, 1 June 2006 (UTC)
thread_title:  Fourth brightest object? 

message: This article says the Spot was first seen by Galileo, the Red Spot article says Cassini in 1665.
Which is it?--Skeev 19:39, 1 June 2006 (UTC)
thread_title:  First seen by....? 

message: Anyone object to altering the third paragraph of the overview?
Most of it seems to be a tangent on the subject of extrasolar planets and not on Jupiter.
Only the last two sentences really seem to deal with the subject of the article. LordNorth 22:46, 2 June 2006 (UTC)
thread_title:  Overview  

message: Did you know that the big red spot in Jupiter,there is a storm every millisecond(however,I don't know the spelling),and it lasted up to 225 million and 2000 years ago(that was when the world started(began.)User:Dark-hooded smoker
:Well, the Great Red Spot is a storm and has been around for quite some time but nobody knows how long. It was first observed around 300 years ago - I'm not sure where you get the 225 million figure from. Even if that was correct, the Earth is a lot older than that - around four and half billion years old. Ajkgordon 08:43, 14 June 2006 (UTC)
thread_title:  Did you know this?(Don't insult me because you already know it) 

message: ::Jupiter is composed of a relatively small rocky core, surrounded by metallic hydrogen, surrounded by liquid hydrogen, which is surrounded by gaseous hydrogen. There is no clear boundary or surface between these different phases of hydrogen; the conditions blend smoothly from gas to liquid as one descends.
Article should mention here: How big is the core, and how big are each of the hydrogen 'shells'? Tempshill 15:24, 17 June 2006 (UTC)
thread_title:  Sizes 

message: Just one question, does the second picture show in the southern section of the planet shows a series of white circles. Could this be the remenents of the schumacher-levie comet? Or is it a storm front like the red spot?Celtic Harper 17:14, 24 June 2006 (UTC)
thread_title:  Impact of Comets 

message: hey everyone,i'm the guy who created about the great red spot lasted since the beginning of the world and the article of jupiter doesn't show when it was discovered.i wanna know when it was discovered,and if someone doesn't edit it and write that when jupiter was discovered,then i ain't gonna be happy with everyone unless someone edits and write when it was discovered.
:Jupiter has been known to man since prehistoric times; it's visible with the naked eye.  Nobody can say exactly when it was discovered. siafu 12:55, 28 June 2006 (UTC)
replies: text: Jupiter was not "discovered" by Galileo, though he was apparently the first to observe it with a telescope, and he did discover the four largest satellites.  Jupiter was also known to Copernicus, for example, even though he didn't have a telescope, and features prominently in quite a few astrological systems from the ancient world. siafu 13:12, 29 June 2006 (UTC)
thread_title:  When was Jupiter discovered? 

message: Maybe this article could make more discussion on what is thought to lie underneath the cloudy surface of Jupiter. Is it a rocky surface like that of the moon. Or is there no surface at all, and maybe there is just a bunch of choatic vapors swirling around forever. I am sure like alot of people, I am fascinated by the planet Jupiter. I am sure the atmosphere is poisonnous to a human being. But if a human being could stand on Jupiter. What would the atmosphere of Jupiter be like. I imagine very heavy and foggy clouds with little or no useful visibility. And how about the gravity in the air. I would like to see much more intimate data be added to the article area for Jupiter over the course of many months. www.geocities.com/berniethomas68 15:48, 1 August 2006 (UTC)
replies: text: There is, technically, believed to be a rocky core of Jupiter, but not a solid surface.  Outside the rocky core are two layers of liquid hydrogen (one metallic), and at these levels the gravity and pressure would crush anything currently buildable by man. siafu 16:07, 1 August 2006 (UTC)
thread_title: Discussion

message: It says that there have been other planets discovered with greater size and mass even than that of Jupiter. And I thought to myself, wow, they have discovered planets that are even bigger than Jupiter. Are these planets outside of our solar system. Maybe someone can shed light on this. I knew the sun was about 600,000 miles around the equator. But I did not think any other planet could have possibly been known to be bigger than Jupiter. www.geocities.com/berniethomas68 15:56, 1 August 2006 (UTC)
replies: text: Several extrasolar planets are believed to be larger than Jupiter, including the one orbitting PSR B1620-26, which is about 2.5 times as massive as Jupiter. siafu 16:01, 1 August 2006 (UTC)
thread_title: In the article

message: I simply failed this article because of the lack of references in the section "Exploration of Jupiter" and after. Find more references, then renominate, because otherwise, it is a fine article.Some P. Erson 23:26, 15 August 2006 (UTC)
thread_title:  Failed GA nomination. 

message: Suppose you wanted to extract hydrogen from Jupiter and ship it around the solar system - how do you get to it? There is no solid footing to land on, any spaceship with tripod legs would sink very very deep before hitting that metallic hydrogen core, and just get crushed and supercompressed to "metallic metal" on the way. One workable way though might be by using a balloon such as the Goodyear Blimp or the Hindenburg, filled with pure hydrogen. As Jupiter is composed of a mixture of hydrogen and helum, a hydrogen filled balloon would float, though not by much. The upper layers are probably richer in the less dense hydrogen, but still containing significant amount of helium, which is twice as dense as hydrogen in gaseous state. You might find it better to locally separate and extract hydrogen via some energy source (such as solar) to keep blowing up larger and larger balloons as platforms for new stuff to land down onto. Another way would be a continuous helicopter-type suspension, but that would require a sustainable fusion engine, which would feed off the atmospheric hydrogen and convert it to helium, but such fusion-based engine is still a far dream for humanity. Any other fuel based engine method (such as nuclear submarine engines with high energy to mass ratio) would have to rely on fuel carried to Jupiter from other, solid astronomical bodies, such as Jupiter's moons or the asteroid belt, and because of the huge gravity and small atmospheric density, it would be very energy-cash prohibitive.  But on Earth we have solar powered airplanes, perhaps one might be able to float in Jupiter too - though solar radiation intensity is much less there. A combo based on a big baloon with a little bit of  thin solar panel powered helicopter nudge to stay afloat may work too. It also might be that filtering that 5 hydrogen atoms per cc in interplanetary space/solar wind may be more feasible than climbing out with hydrogen cargo from Jupiter's immense gravity. Sillybilly 07:05, 16 September 2006 (UTC)
replies: text:  Forget about vacuum filled containers, or even low Earth-pressure filled containers  - the walls would have be too thick and heavy for the required strength. I'm not even dreaming of humans landing on Jupiter, because the gravity there is so great, you'd probably end up with heavy skeletal disorders. I'm thinking about remote controlled robots landing, even that's a very difficult difficulty. We can easily generate artificial gravity where there isn't any, by centrifugal force - rotating space stations, huge merry-go round type Moon and Mars station buildings, but there is no way I can think of to undo gravity, to generate negative gravity or negative centrifugal force, negative acceleration, other than freefalling, but that's not sustainable for too long. Sillybilly 07:20, 16 September 2006 (UTC)
replies: text:  I never mentioned a single thing from that entire reply.. please do not read stuff into what i post -- Nbound 07:23, 16 September 2006 (UTC)
thread_title:  How do you land on Jupiter?