Talk:Lunar water
{{WikiProject banner shell}}
to this page and add the quality rating to that template instead of this project banner. See WP:PIQA for details.![]() | Astronomy C‑class High‑importance | |||||||||
|
Rename
I suggest we rename this article "Water on the moon", or "Lunar water", or some other title that uses the word "water" rather than specifically "ice". This would be a better reflection of its contents now. Any thoughts? 86.133.245.56 (talk) 23:26, 6 October 2009 (UTC).
- I agree, as it refers to the water element whether bound or in free form, not to the state of it as liquid, ice or vapor. BatteryIncluded (talk) 17:26, 9 October 2009 (UTC)
- I third the idea Water on the moon is probably much easier to identify.Moonus111 (talk) 03:24, 11 December 2010 (UTC)
Dubious
I assume that the claim in the opening sentence that lunar ice is "known to exist" refers to the recent Chandrayaan findings. I'm no expert, but my understanding is that what Chandrayaan found is not what most people would call "ice". My understanding is that it found either H2O or OH chemically bound to moon rocks -- nothing like "ice" at all, in fact.
Later on, the article also has a section headed "Confirmation of lunar ice" which seems equally dubious to me.
I think the article needs a full review of the choice and use of words "water" and "ice". Notwithstanding the media headlines, is it even reasonable to say that Chandrayaan discovered "water" on the moon? 86.152.242.223 (talk) 00:16, 11 October 2009 (UTC)
Also, "Lunar water is water ice..." seems an odd and confusing opening to me. If we're including water of hydration in minerals in the discussion then it's not true, is it? In the opening I think we need a better explanation of the forms in which "water" might exist on the moon. —Preceding unsigned comment added by 86.152.242.223 (talk) 00:22, 11 October 2009 (UTC)
Detection of water ice
The article has been amended recently to cover the recent LCROSS discoveries, and the text is now written throughout from the perspective that water ice has definitely been found. However, the main supporting reference, http://www.nasa.gov/mission_pages/LCROSS/main/prelim_water_results.html, does not actually say this. It says that water was detected in the ejecta but not that it came from free water ice on lunar surface. Are we sure it did come from water ice -- that is, pieces of frozen water that you and I would recognise as "ice" -- and not from hydrated minerals or similar? 86.134.9.62 (talk) 15:17, 16 November 2009 (UTC).
- Although "additional confirmation" came from an emission in the ultraviolet spectrum that was attributed to hydroxyl, the reference you indicate does not say 'hydrated materials' but "water":
- "LCROSS, indicates that the mission successfully uncovered water..."
- "water, which could be more widespread and in greater quantity than previously suspected."
- "The team concentrated on data from the satellite's spectrometers, which provide the most definitive information about the presence of water.
- "Multiple lines of evidence show water was present in both the high angle vapor plume and the ejecta curtain created by the LCROSS Centaur impact."
- "The concentration and distribution of water and other substances requires further analysis, but it is safe to say Cabeus holds water."
- We were only able to match the spectra from LCROSS data when we inserted the spectra for water. No other reasonable combination of other compounds that we tried matched the observations."
- Cheers, --BatteryIncluded (talk) 19:15, 16 November 2009 (UTC)
- Sure, I understand all that, but if you smash a large mass into rock or dirt, generating lots of heat and energy, and you then detect water in the ejecta, does that necessarily mean that there was water ice in the rock or dirt? Or could all that energy have liberated water that was chemically bound to the rocks? I don't know the answer, but I can't find any source that absolutely explicitly states that the water detected must have come from free water ice at the Moon's surface. 86.134.30.157 (talk) 20:14, 16 November 2009 (UTC).
- I see. Water seems to be present only as a faint soil moisture. However: "The quantity of water found is equivalent to that found in the driest of desserts on earth, says Jim Garvin, Chief Scientist at NASA Goddard research center, but considering it was found on a planet without an atmosphere, surrounded by the vacuum of space, the amount is extraordinary and has NASA excited."[1] They started taking about a lander with a core drill and analytical capabilities. --BatteryIncluded (talk) 03:20, 17 November 2009 (UTC)
- I am very confused about what these reports of "moisture" and "humid soils" actually mean. I am still unclear whether the results of Chandrayaan-1, for example, definitely mean that there are molecules of free water abounding across large areas of the Moon. For example, one of the sources cited ([2]) says that "very fine films of H2O coat the particles that make up the lunar dirt". To me, this implies free water molecules. But another ([3]) says that the water is "tightly bound to minerals", which to me implies chemically bound, as in hydrated minerals, i.e., not in a form that you and I would recognise as "dampness" or "moisture". I'd love for an expert to come along to this article and really nail all these points. 81.129.130.64 (talk) 14:30, 17 November 2009 (UTC).
- And, while we're at it, I am not at all happy* about relying on sources in the popular media (The Times newspaper, for example) to support the technical aspects of the article. The popular media cannot be relied upon to use scientifically accurate language or understand with scientific precision exactly what it is they are talking about. 81.129.130.64 (talk) 14:35, 17 November 2009 (UTC). *Sorry, re-reading that, it kind of sounded as if I was criticising you. Absolutely not. In fact, it's quite possible that I added The Times reference.
- No biggie. Your concerns and questions are valid. Yes there seems to be some contradiction on whether it is 'moist soil' or chemically-bound hydrated minerals, and I think that NASA is working it out slowly. The data will be published in scientific journals and shared with teams around the world, then, new physical models will be proposed and will be compared to the observed data. It is a matter of keeping an eye in the subject and updating the article as the months and years go by. Please feel free to update the article now as you see fit. Cheers, --BatteryIncluded (talk) 21:42, 17 November 2009 (UTC)
- Hi again, BatteryIncluded, I see you've made some edits and added some caveats. I like what you've done. Another thing I wonder if we should change is the following statement in the lead (which I originally patched together when redoing the lead section post-LCROSS):
- "Inconclusive evidence of such water ice was accumulated from a variety of observations, until, in November 2009, NASA finally confirmed that its LCROSS space probe had detected a significant amount of water in the material thrown up from a south pole crater by an impactor."
- This sentence implies that the LCROSS observations turn inconclusive evidence into conclusive, and thereby prove that (free) water ice is definitely present on the surface -- a claim for which I can find no solid source. It now also contradicts the later statement that "what was actually detected was the chemical group hydroxyl ( · OH), which is suspected to be from water, but could also be hydrates, which are inorganic salts containing chemically-bound water molecules." Since you've been researching this, I wondered if you had any ideas on how to reword this part of the lead? 86.134.43.29 (talk) 03:50, 20 November 2009 (UTC).
- There is no doubt in my mind that NASA is puting the most positive spin to the interpretation because of politics, as financing for many important projects depends on the discovery of usable amounts of accessible water on the Moon. The hard fact is that scientific papers are more precise than press releases, so the hydroxyl article has precedence: Hydroxyl was detected, and it could be water. --BatteryIncluded (talk) 06:29, 20 November 2009 (UTC)
- Can't read it without a subscription but the impact occured on 9th October whereas that article is dated 24th September ~ R.T.G 11:53, 20 November 2009 (UTC)
- The LCROSS science instrument payload consisted of nine instruments: one visible, two near infrared, and two mid-infrared cameras; one visible and two near-infrared spectrometers; and a photometer. Yes, the paper was published before the impact.
Latest articles
"There's not one flavour of water on the Moon; there's a range of everything from relatively pure ice all the way to adsorbed water," said the mission's chief scientist Anthony Colaprete, from Nasa's Ames Research Center. [4]. --BatteryIncluded (talk) 04:03, 9 March 2010 (UTC)
- In the March 18, 2010 press release by NASA they speak of the "discovery of 600 million metric tons of water", however, this is very misleading and imprecise. As explained above and in this Wikipedia article, what they found is hydroxyl group, and in NASA's press release (image caption) you can read:
- "The Mini-SAR has imaged many of the permanently shadowed regions that exist at both poles of the Moons. These dark areas are extremely cold and it has been hypothesized that volatile material, including water ice, could be present in quantity here."
- So, what they found is cold dark spots, and are working on hypotheses. The Moon teams in NASA are putting the best possible spin to this so that they get funding to go back to the Moon, so these releases may be politically motivated. Let's place more importance to the published scientific articles. --BatteryIncluded (talk) 15:21, 21 March 2010 (UTC)
- Thanks for your observation. I guess I was suckered. I have modified the text to make the hypothetical nature of the discovery more explicit. --Ben Best (talk) 17:34, 21 March 2010 (UTC)
- The end result of several edits seems to have been to remove all mention of the Mini-SAR results from the lead section. Was that the intention? 86.133.54.12 (talk) 21:58, 21 March 2010 (UTC)
- The purpose should be to state what is known (hydroxyl group detected) and include some of the hypotheses. --BatteryIncluded (talk) 23:43, 21 March 2010 (UTC)
- I'm not sure if Mini-SAR is capable of distinguishing "hydroxyl". To quote NASA:
- "Mini-SAR is a lightweight (less than 10 kg) imaging radar. It uses the polarization properties of reflected radio waves to characterize surface properties. Mini-SAR sends pulses of radar that are left-circular polarized. Typical planetary surfaces reverse the polarization during the reflection of radio waves, so that normal echoes from Mini-SAR are right circular polarized. The ratio of received power in the same sense transmitted (left circular) to the opposite sense (right circular) is called the circular polarization ratio (CPR). Most of the Moon has low CPR, meaning that the reversal of polarization is the norm, but some targets have high CPR. These include very rough, fresh surfaces (such as a young, fresh crater) and ice, which is transparent to radio energy and multiply scatters the pulses, leading to an enhancement in same sense reflections and hence, high CPR. CPR is not uniquely diagnostic of either roughness or ice; the science team must take into account the environment of the occurrences of high CPR signal to interpret its cause."
- I take on board the cynicism that NASA are bigging up the results for political/funding reasons, but they really do seem quite definite that the instrument has detected ice deposits near the moon's north pole (See http://www.nasa.gov/mission_pages/Mini-RF/multimedia/feature_ice_like_deposits.html). Unless there's something I'm missing, this is important enough to go into the lead section. 86.134.115.202 (talk) 03:37, 26 March 2010 (UTC).
- The hydroxyl determination or discovery was done with other instruments. I have no time now but I can describe it later. Cheers, --BatteryIncluded (talk) 18:52, 26 March 2010 (UTC)
- Yes, I'm aware of that. As I have tried to make clear throughout this exchange, I am talking about the Mini-SAR experiment. 86.137.136.203 (talk) 21:58, 26 March 2010 (UTC)
Now NASA is claiming 5.6 - 8.5% pure water ice crystals (not hydroxyl bound) in the Cabeus crater, should we updte the article?:
"the water is in the form of almost pure ice grains mixed in with the rest of the soil, and is easy to extract. The ice is about 5.6 percent of the mixture, and possibly as high as 8.5 percent of it, Dr. Colaprete said." (source here) --BatteryIncluded (talk) 21:52, 21 October 2010 (UTC)
- Updated Main Article To Latest (definitive) Findings re Detected Water Concentration -> A later definitive anaylsis found the concentration of water to be "5.6 ± 2.9% by mass."[1] Drbogdan (talk) 20:11, 22 October 2010 (UTC)
Moonwater
A Moonwater article has appeared, I believe this should redirect to this much fuller article. What do others think? Graeme Bartlett (talk) 02:17, 19 March 2010 (UTC)
- Agreed. My bad for not thinking to check for "Lunar water", I'll redirect. — Aldaron • T/C 03:55, 19 March 2010 (UTC)
- ^ Colaprete, A.; Schultz, P.; Heldmann, J.; Wooden, D.; Shirley, M.; Ennico, K.; Hermalyn, B.; Marshall, W; Ricco, A.; Elphic, R. C.; Goldstein, D.; Summy, D.; Bart, G. D.; Asphaug, E.; Korycansky, D.; Landis, D.; Sollitt, L. (22 October 2010). "Detection of Water in the LCROSS Ejecta Plume". Science. 330 (6003): 463–468. doi:10.1126/science.1186986.
{{cite journal}}
: CS1 maint: multiple names: authors list (link)