Talk:Titan (moon)
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Selected entry on Template:March 25 selected anniversaries (may be in HTML comment)
The adjectival form of Titan is either Titanian (which would include inhabitants) or Titanic. Titanian is shared with the moon Titania.
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False-colour image
(P3d0) Does it make sense to have a false-colour image as the image for this article?
- IMO, the "primary" image for a planet or moon should be as close to true-colour as possible. I recall there was a similar discussion over the image for Venus (planet) a while back, and while the current primary image isn't true-colour (it's in the ultraviolet, a true-colour image of Venus is pretty much featureless) it's still closer than the Magellan radar map that was there for a little while. Bryan 02:20, 28 Oct 2004 (UTC)
- I think the old image should be put back and the new false colour image should replace the older, low-quality one at the bottom which has now been superseded. I'd do it myself but I've got to go to work!! The Singing Badger 12:19, 28 Oct 2004 (UTC)
Done. Awolf002 14:26, 28 Oct 2004 (UTC)
"Significant atmosphere"
[no user login] - article refers to Titan as only N2 rich atmosphere. Believe Triton's atmosphere is almost pure N2
- It is a question of reification (¿when is a thing a thing?). Some gas is around Triton. ¿Is sufficiently thick to me an atmosphere? ¿Is our moon airless or does it have an extremely thin atmosphere of sodium-vapor? ¿Is Io airless or does it have an atmosphere of sulfur-vapor? ¿Is Europa airless or does it have a thin atmosphere of oxygen? ¿Is Mercury airless or does it have an atmosphere of helium? ¿Is intergalactic space airless or does it have an Hydrogen/Helium-atmosphere with a density of one atom per cubic centimeter? Most planetologists ask themselves, "¿Whether the world has weather?" Triton is a bordercase:
If the Nitrogen of Triton would just lie around, it would make support clouds. Triton has geysers. The nitrogen significantly slows the fall of particles from the geysers. One could argue it either way. Personally, I would say that Triton has an insignificant atmosphere. Titan, on the other hand has a very significant atmosphere (both in mass and density, the atmosphere of Titan is greater than that of Earth).
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Ŭalabio 02:10, 2005 Jan 15 (UTC)
Interior
I couldn't find anything in the article about the interior of Titan- did I miss it, or have we missed it out? This BBC report (http://news.bbc.co.uk/2/hi/science/nature/4196261.stm) suggests that the interior is a rather exciting place: "However, models of Titan's interior show there should be an ocean about 100km deep at around 300km below the surface." If the models are correct, this ocean would be composed mostly of liquid water with about 15% ammonia at a temperature of about -80C. Mark1 06:16, 26 Jan 2005 (UTC)
Methane Oceans
I know ESA talks a lot about methane oceans and lakes, but the fact is methane partial pressure in titan is insufficient for condensation, so methane is only stable as a gas and as a solid.
Ethane lakes can exist, and there is a lot of ethane around. Ethane can dissolve methane, so those lakes can be a mix of ethane+methane.
So, should this be mentioned in the article?
--Rnbc 18:52, 2005 Jan 28 (UTC)
- If those are true facts (not saying they aren't just that I don't personally know whether they are) then by all means they should be in the article. This is exactly the sort of information encyclopedia articles are for. :) Bryan 00:44, 29 Jan 2005 (UTC)
- Ideally, you'd also give a citation for your information. --P3d0 04:10, Jan 29, 2005 (UTC)
- Well, you can just grab your calculator and do some math yourself :-) Methane triple point pressure (taken from wikipedia) is 11700 Pa, so that's the absolute bare minimum partial pressure for condensation. Titan's average temperature seems just above methane's triple point (-182C), at -180C, so we are ok from a temperature POV. Now the problems start: The atmosphere has only 6% methaneand the pressure at the surface is about 160000 Pa, witch means methane partial pressure is only ~9600 Pa, below the bare minimum 11700Pa required for condensation. On Earth the atmospheric water content is much below 6%, but the triple point condensation pressure is only 611 Pa, so this is not a problem. For water condensation to occur on Earth only 0.6% of atmospheric water content is required since the normal pressure is about 101000 Pa. By comparison Ethane's triple point is at 1.1 Pa and -182C, so Ethane certainly condenses, despite being relatively rare. Methane is converted into Ethane by solar radiation. Now, I'm not a specialist, so I would like someone with better knowledge to review what I wrote here. --Rnbc 22:58, 2005 Feb 2 (UTC)
- I think you underestimate your own level of knowledge. Verifying what you have just said requires more than just math; it requires a level of chemistry and physics knowledge that the typical reader (such as myself) would be unable to verify. So I'd still feel more comfortable with an authoratative reference for this, especially if we're going to contradict NASA experts. However, if others find your reasoning convincing, then that's fine by me. --P3d0 17:30, Mar 24, 2005 (UTC)
- Just out of curiousity, where did you get the amount of methane in Titan's atmosphere from? In particular, is it pre-Huygens, and is it based on the upper atmosphere? According to this ESA website [[1] (http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36396)], the concentration of methane increases nearer to the surface. This page also claims that the main liquid on Titan's surface would be methane. If the methane abundances are higher at the surface, it may be possible that the total of amount of methane in Titan's atmosphere has been underestimated. In that case, near the surface, the amount of methane may be enough to rise above the tripple point. I've been looking for an actual numerical result from Huygens, though no success so far. (There is also the question of how sensitive the triple point is to impurities. By adding some salt to water, for example, the freezing point can be lowered; could some minor impurities lower the amount of partial pressure needed enough for methane to condense on Titan's surface?) The Reflection 00:42, 25 Mar 2005 (UTC)
Here's a link to a better picture of the titan "shoreline." I'm not sure if it's in the public domain:
Magnitude
Is the magnitude mentioned Apparent or Absolute? Just wondering...
The magnitude is apparent. For the absolute magnitude (using the definition for planets, not stars), I get something around 3. The Reflection 04:15, 22 Mar 2005 (UTC)
Wikipedia:WikiProject Fact and Reference Check
Some useful sources for this article:
- http://www.nasa.gov/mission_pages/cassini/media/cassini-0703.html
- http://saturn.jpl.nasa.gov/science/titan.cfm
- http://saturn.jpl.nasa.gov/science/titan-atmosphere.cfm
- http://saturn.jpl.nasa.gov/science/titan-surface.cfm
- http://www.solarviews.com/eng/titan.htm (Is this a usable source?????)
- http://www.esa.int/SPECIALS/Cassini-Huygens/
Some more sources:
- http://huygensgcms.gsfc.nasa.gov/Titan.htm - physical data, mainly.
JesseW 22:08, 29 Mar 2005 (UTC)
Another is http://nssdc.gsfc.nasa.gov/planetary/factsheet/galileanfact_table.html. Which is also mainly physical and orbital data. The data there is slightly different (Looks like entirely due to significant digits or rounding) from what is in the article. Does anyone know where the data in the article's table is from? It seems we can add footnotes to every physical fact in the table to this NASA site. I also don't know how to format that as a reference. Any ideas? - Taxman 17:46, Mar 30, 2005 (UTC)
- Just put it as a footnote from the table section headings. Mozzerati 20:21, 2005 Apr 1 (UTC)
This article is no longer the biweekly special article for Wikipedia:WikiProject Fact and Reference Check. In the two weeks that it was, this article got 22 references! -Frazzydee|✍ 18:10, 13 Apr 2005 (UTC)
I love the work done on this article! Look at all the facts that were referenced. Wikipedia might become the most verified and authenticated source of information ever created. It is very exciting, and even if someone can only do one fact reference it is an effort well worth the trouble :)). --ShaunMacPherson 21:37, 16 Apr 2005 (UTC)
Errors
A positive consequence of referencing facts in an article is that it is easy to spot errors. Below is a list of errors found by the Fact and Reference Check team.
- Saturni Luna: I believe that Titan was called Luna Saturni, and not Saturni Luna when first discovered. There's a NASA site and a book reference on the article page. There was one PDF file (titled 'mythology of titan') that claimed it was 'saturni luna', but a google search seems to show more for luna saturni. Also, another NASA page writes it as Luna Saturni, and a published book also has it as Luna Saturni. I think it's fairly safe to say that Wikipedia was wrong, but please correct me if you disagree, because the answer is not completely clear. -Frazzydee|✍ 05:23, 31 Mar 2005 (UTC)
- Without disagreeing, it's worth noting that in Latin it doesn't matter which way round the words go, so astronomers could have used either name without being 'wrong'. The Singing Badger 17:13, 1 Apr 2005 (UTC)
Featured article?
I think with a few minor changes this is a good featured article candidate. Just a suggestion—something to consider for the people who have been editing this article (and editing it so well). Hydriotaphia 13:24, May 11, 2005 (UTC)