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Hi, I am working to encourage implementation of the goals of the Wikipedia:Verifiability policy. Part of that is to make sure articles cite their sources. This is particularly important for featured articles, since they are a prominent part of Wikipedia. The Fact and Reference Check Project has more information. Thank you, and please leave me a message when you have added a few references to the article. - Taxman 17:43, Apr 22, 2005 (UTC)

On Jeopardy today there was a clue where the answer (question) was "What is IO?" but the guy said "What is EO?" and they accepted it. This made me wonder if there was another pronunciation. I looked around and found this PBS webpage that says the 4 moons are "Eo, Europa, Ganameta, and Callisto". Is Eo an alternate spelling? What's the deal? -- 1 July 2005 06:01 (UTC)

No, but it's an alternate pronunciation. I assume that the Jeopardy answer was spoken, not written? I also notice that the PBS page is a transcript, and transcribers have to write down a lot of stuff they know nothing about; especially with proper names, they often just make a guess at the spelling. Note that 'Ganymede' is also spelled wrong. From the transcription, I'd guess that guy they were interviewing was trying to recreate the Classical Greek pronunciations. (Each of the moons in Wikipedia is listed with its Greek source, if you want to check it out, although a few are missing stress markings.) The Galilean moons would be pronounced [iː.ˈɔː] for Io (Îô), which with an English accent would come out as EE-oh; [ew.ˈrɔː.pɛː] for Europa (Eurôpê); [ga.ny.ˈmɛː.dɛːs] for Ganymede (Ganymêdês); and [kal.li.ˈstɔː] for Callisto (Kallistô). —kwami 2005 July 1 07:11 (UTC)

P.S. A couple months ago, the various moon names were a hodgepodge of pseudo-Greek and naturalized English pronunciations, with no indication of what was what. They should now all have naturalized pronunciations, but for those who wish to pronounce Titan as tee-TAHN, the Greek (or Latin) is there as well.

Oops, I take back part of my comment. The 'Classical' pronunciations are sometimes an attempt to recapture the Latin version of the names, not the original Greek. (They were borrowed by the Romans from the Greeks, and we got 'em from the Romans.) In these cases the stress would be the same as in English: Io would be EE-oh rather than ee-OH, and Titan would be TEE-tahn. kwami

Galileo himself noted that Marius used the Julian calendar while Galileo used the Gregorian one. This is not made clear as it is. Of course, the two calendars and the different parties using them are well known. — Preceding unsigned comment added by 92.26.0.234 (talk) 14:26, 22 September 2014 (UTC)[reply]

The date of Galileo's publication, 1610, is not logical proof that he made any observations before Marius. Galileo's direct argumentation should be used. I think his argumentation is indeed proof that he did have priority, not that it is very important. — Preceding unsigned comment added by 92.26.0.234 (talk) 14:34, 22 September 2014 (UTC)[reply]

Logical or not, publication was traditionally used to determine priority as it was the first evidence that was available to people in general (and possibly because it encouraged people to publish?)

IceDragon64 (talk) 23:06, 20 January 2019 (UTC)[reply]

The introduction states that Io has the least amount of water of any celestial body; that would include the Sun, planet Venus and the tiniest asteroids. A user held a hot debate about that topic on Tbayboy's talk page and this link provided by the user states there might a sub-surface ocean on Io just like on the other Galilean moons. Maybe the introduction should better say Io has the least water out of all moons, that would certainly be true (if the assumption of a sub-surface ocean is wrong), but not every celestial body. Come on! Io can't have less water than the Sun or tiny asteroids, can it? -- 12:34, 6 May 2019 (UTC)

Some more context: There's a statement in Surface Composition saying "Io has the least amount of water of any known body in the Solar System", with a reference to a published textbook. It's also repeated in the lead.

My own comments:

• The German page above doesn't seem reliable: Given Io's constant volcanism, any sub-surface ocean would be coming out with the eruptions and would be spewed across the surface or in the plumes. It would be easily seen. I think the author got confused reading about Io's possible sub-surface magma ocean and its comparison with the water oceans of the other moons.
• Does the source say Io has the least total mass of water, or the least fraction? It's hard to believe that Io, dry as it is, has less water than some little asteroid.
• If it's water fraction, wouldn't the Sun have less? Or was it implicit in the source that the Sun was excluded?
• Most importantly, is there any data on the quantity/fraction of water in all known bodies for this statement to have any meaning? I find it hard to believe they even know how much water Io has at all, if you include possible internal supplies.

It's certainly worth noting how dry Io is, but saying it has the least water seems a stretch. Could somebody with access to the source (Seeds, Michael A.; Backman, Dana E. (2012). The Solar System (8th ed.). Cengage Learning. p. 514. ISBN 9781133713685) please check it? Tbayboy (talk) 15:36, 6 May 2019 (UTC)[reply]

Sub-surface MAGMA ocean, not water. Based on spectroscopic measurements going back to the 1970s all the way through Galileo NIMS have found no evidence for water ice on Io beyond some evidence for hydrated minerals north of Gish Bar Mons, though other molecules are possible candidates including SO3 and S2O (or other polysulfoxydes) (Doute et al. 2004). Is it possible there is water locked in Io's interior? Sure, I guess anything is possible, but this is a world that literally spits its interior out into space and back onto its surface. If there was water in its interior, it should have been observed either through spectroscopy of surface frosts and volcanic plume deposits or by observing Io's plumes as they transit a star. At least water vapor has been found at the Sun... Volcanopele (talk) 20:20, 6 May 2019 (UTC)[reply]

The source claims there might be a water ocean beneath Io. On the Sun, where does the water vapor come from? -- 06:41, 7 May 2019 (UTC)

I think that source is wrong: they confused magma ocean with water ocean. It's just a pop-sci website, and I couldn't find anybody else making that claim with a quick google. On the Sun, there's lots of hydrogen and a bit of oxygen, and they cool enough to combine for a while in sunspots. Tbayboy (talk) 11:53, 7 May 2019 (UTC)[reply]

The source might err, but I still don't believe that Io has less water than 10-feet-long meteoroids. 212.186.0.174 (talk) 13:52, 7 May 2019 (UTC)[reply]

10-feet long meteoroids can have a lot of water. Ruslik_Zero 06:20, 8 May 2019 (UTC)[reply]

More than Io has? 212.186.0.174 (talk) 08:28, 8 May 2019 (UTC)[reply]

If you see my question why don't you respond? If you don't know, say that you aren't sure. 212.186.0.174 (talk) 11:04, 10 May 2019 (UTC)[reply]

We (obviously) don't know the hard numbers. There may not even be any numbers. But Wikipedia goes by sources, not what we surmise, and all the reliable sources say Io is about as dry as it gets. Asteroids, generally, aren't that dry (water is bound up in the rock). Without any reliable sources to the contrary, we go with what the one referenced in the article says. I would like to check that the statement here matches the source, but don't have access to the source. Tbayboy (talk) 12:06, 10 May 2019 (UTC)[reply]

I think it's anyway unwise to mention the absolute amount of water rather than the amount relative to the size of the body. If one mentioned the latter one I think Io has a higher percentage of water than the Sun or Venus. 212.186.0.174 (talk) 17:07, 10 May 2019 (UTC)[reply]

If you can find a reliable source stating the moon Io has water, or any facts about the amount of water on IO, then link it and edit the article, but if we can't find a reliable source , we can't add it. MaximusEditor (talk) 09:25, 24 September 2020 (UTC)[reply]

There are some issues with the article including over a dozen cn tags, some ^{[better source needed]} issues (the ones that I found are marked in the article), and some verifiability issues with page ranges of 20 pages or more. (t · c) buidhe 08:31, 13 February 2022 (UTC)[reply]