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Enceladus "Sea" Mystery Deepens

Posted by kdawson on Tue Dec 18, 2007 10:59 PM
from the who-moved-my-sodium dept.
Smivs writes "The BBC reports that an ocean may not be the source of the jets emanating from Saturn's moon Enceladus. Controversial research questions the moon's promise as a target in the search for life beyond Earth. A chemical analysis of Enceladus, led by University of Colorado planetary scientist Nick Schneider, failed to detect sodium, an element scientists say should be present in any body of water that has been in contact with rock for billions of years. Spectral analysis with the Keck Telescope found no sodium in the plumes or in the vapor in orbit around the moon. At stake is whether Saturn's moon could support alien life and is thus a worthy target for a NASA exploratory mission to detect it. Such a mission to Enceladus is one of four currently under review for further development."

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[+] Spacecraft to Fly Through Geyser Plumes On Saturn Moon 80 comments
Riding with Robots writes "Today the robotic Saturn probe Cassini will make its closest buzz ever over the surface of the enigmatic ice moon Enceladus, whose surprising giant water geysers hint at a hidden ocean of liquid water. The spacecraft will fly right through the tops of the geyser plumes in order to sample the material that originated beneath the surface. NASA is offering a video, interactive guide and image gallery in advance of the event."
[+] Cassini 'Tastes' Organic Material at Enceladus 4 comments
Riding with Robots writes "As previously reported, the robotic spacecraft Cassini recently flew through the mysterious geyser plumes at Saturn's icy moon Enceladus. Today, NASA released the preliminary results of the flyby, including some intriguing findings, such as organic materials 20 times denser than expected and relatively high temperatures along the fissures where the geysers emanate. 'These spectacular new data will really help us understand what powers the geysers. The surprisingly high temperatures make it more likely that there's liquid water not far below the surface,' said one mission scientist."
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  • The Tiger Stripes are not Cracks (Score:3, Interesting)

    by pln2bz (449850) * on Tuesday December 18, @11:01PM (#21747696)
    • Informative to whom? (Score:4, Informative)

      by TapeCutter (624760) on Wednesday December 19, @01:15AM (#21748490) Journal
      A link to the electric universe nonesense posted by slashdot's #1 EU fanboy is about as informative as "The DaVinci Code", "State of Fear" or "The Panda's thumb".
      [ Parent ]
        • Re:Informative to whom? (Score:4, Insightful)

          by Iron Condor (964856) on Wednesday December 19, @03:09AM (#21749036)

          The earth is NOT flat because one can fly around it.

          Now this is not an easy undertaking -- quite a bit of time, money and effort has to be expended to fly around the earth.

          But after you've done it, after you've flown around the earth yourself, you do not have to give "equal time" to the notion of a flat earth anymore.

          [ Parent ]
    • 1. The discoverer pitches the claim directly to the media.
      Check

      2. The discoverer says that a powerful establishment is trying to suppress his or her work.
      Check

      3. The scientific effect involved is always at the very limit of detection.
      Check

      4. Evidence for a discovery is anecdotal.
      Check

      5. The discoverer says a belief is credible because it has endured for centuries.
      Check

      6. The discoverer has worked in isolation.
      Check

      7. The discoverer must propose new laws of nature to explain an observation.
      Check.

      [ Parent ]
          • Re:Moderator on Crack (Score:4, Funny)

            by SL Baur (19540) <sl.baur@gmail.com> on Wednesday December 19, @03:59AM (#21749270) Homepage
            Oh thank you, thank you, thank you. I'm soooo glad to have someone reliable and unbiased like Wikipedia to do my thinking for me.

            The sad fact of science is that scientific knowledge comes in waves and only advances past a certain point when the main proponent of a previous world model is dead.

            Shame on you, the electric universe guys who flame (and mod down here) everyone who does not agree with you. Shame on you wikipedians for being unable to keep your own bias out of wikipedia.

            I was inclined to be sympathetic to the electric universe guys just on general principles (magnetism is a huge effect), but no more, thank you. Anyone who has to make an argument by silencing opposition (or apparent opposition) just does not have a leg to stand on, in my opinion.

            Oh my god. I've offended both sides. Better moderate me into oblivion so no one else can hear since you can't delete this post.
            [ Parent ]
            • Re:Moderator on Crack (Score:5, Insightful)

              by GTMoogle (968547) on Wednesday December 19, @09:14AM (#21750468)
              There's also the sad fact that there are a number of scientists who have a stroke of what they assume is brilliance and ignore the inadequacies of their theory and any contradictory evidence. The momentum of scientific thought, as much as it hurts revolution, also protects science from a lot of inane BS.

              That's not to say I think either side is right or wrong. But we shouldn't assume that the underdog is right *just because* he's fighting the establishment.

              "To be a persecuted genius, you not only have to be persecuted; you also have to be right." (Asimov)
              [ Parent ]
                • Re:Moderator on Crack (Score:4, Insightful)

                  by APODNereid (1203758) on Wednesday December 19, @03:00PM (#21754570)

                  The idea that electricity flows through space is not at this point inane BS. It's already accepted that electrical flows occur from the Sun to the Earth.
                  One of the many advantages to operating within the standard (plasma physics, space science) scientific paradigm is that key terms are clearly defined, and connections with the underlying (physics) theory easily traced.

                  One of the disadvantages to operating outside this paradigm is that key terms lose their precision, communication becomes fuzzy, misunderstandings all too common, and so on.

                  If by the above you are referring to the solar wind, then of course you're right, and we can turn to any number of standard textbooks and scientific papers to explore the topic in as much depth as any reader wishes.

                  However, if by the above you mean something like Juergen's currents, or the idea that the Sun is powered (largely) by a giant inter-stellar current, then we are adrift without a paddle ... we have no minimal mutual understanding on which to base further dialogue.

                  Is it so insane to include as a *possibility* that they are being etched by plasmas? Not really.
                  Quite right.

                  However, the difficulty comes once you accept that *possibility* ... how do you begin to test it? For what you've written these last few days, in SD, it is clear that:

                  a) you reject - out of hand - any testing done within the standard scientific paradigm of plasma physics or space science;

                  b) you offer no alternative means by which any such testing could be done.

                  I'm just trying to have a conversation, really, because I honestly don't trust the establishment to admit that it is wrong on this issue. What they're going to do is work their way to the same conclusions the hard way, by fighting tooth and nail to avoid considering the possibility that electricity does things of importance in space, and people like you and I will probably be dead by the time it happens.
                  Ah, the eternal excuse - I can't tell you anything about my electromachining (or whatever you call it) idea, nor can I suggest any way anyone could even *begin* to draft a programme to test it, because I honestly don't trust the establishment to admit that it is wrong on this issue!

                  Would you mind explaining the logic here please?

                  The plume on Io, for god's sake, looks *exactly* like the output of a plasma gun.
                  It does? '*exactly*'?

                  How did you come to that conclusion?

                  In what - quantitative - sense is it *exact*?

                  Images from Kristian Birkeland's terrella experiments from 100 years go are so identical to eclipsed shots of Io (with its hot point sources) that the two images are literally impossible to distinguish.
                  They are?

                  I thought Birkeland's 'images' are on photographic emulsion, and 'images' of 'eclipsed shots of Io (with its hot point sources)' are the result of an extremely complex chain of processing, using many, detailed, mathematical models (the spacecraft to ground station commslink alone is a marvel of modern technology). Am I mistaken?

                  People who argue that we should not investigate these things are basically assuming their way to their own conclusions.
                  Who so argues? Certainly not the dozens of PhDs who write papers on the landforms of Mars, etc!

                  These ideas should not be judged within the assumptions of papers.
                  Not even - Flying Spaghetti Monster forfend! - within the assumptions of 'EU Theory' papers (should any ever get written)?

                  We should evaluate the concept of electrical terraforming instead within the conclusions.
                  What does this mean? What 'conclusions'? Reached how? Using which parts of plasma (or related) physics?
                  [ Parent ]
  • Sodium Depletion Due To... (Score:5, Funny)

    by haakondahl (893488) on Tuesday December 18, @11:12PM (#21747778)
    ...overmining by the Europans. Yes, the sole hyperpower in far solar orbit is exploiting the resources of honest, hard-working, frozen Enceladans. Don't buy Morton Salt.
  • so (Score:3, Funny)

    send the probe to enceladus anyways

    just put a salt shaker on it

    problem solved

    sheesh these scientist types and their "problems"
  • Off the map? (Score:3, Insightful)

    by CraftyJack (1031736) on Tuesday December 18, @11:34PM (#21747900)

    At stake is whether Saturn's moon could support alien life and is thus a worthy target for a NASA exploratory mission to detect it.
    I can think of plenty of outer planet exploration missions that don't have detection of life as a goal. I think the presence of liquid water will keep a mission to Enceladus on the roadmap. Astrobiology is strapped for cash anyway.
  • Waste of Money (Score:5, Interesting)

    by mothlos (832302) on Wednesday December 19, @12:10AM (#21748124)
    Although a lack of salt is a fine excuse to not send a mission here, the better reason is that these missions are a tremendous waste of taxpayer resources. While I am no free market capitalist, it is waste like this which give fire to those who say that government can't make financially sound decisions. Lets focus our space program on useful tasks such as orbital solar energy collection and leave the fruitless search for extraterrestrial life to the hobbiests.
    • Re:Waste of Money (Score:5, Insightful)

      by Anonymous Coward on Wednesday December 19, @12:31AM (#21748224)
      It's really not a total waste of government money, because once alien life is found it will be a great tool for controling the masses through fear. Just think - instead of fearing another country we could now fear life from other planets. That should keep us busy for a couple of generations...
      [ Parent ]
    • Re:Waste of Money (Score:5, Insightful)

      by rve (4436) on Wednesday December 19, @02:20AM (#21748842)
      It costs very little. The entire NASA funding is less than half of a percent of the government budget, it really is a pittance. Only a very small percentage of the NASA budget is used for space exploration.

      One Iraq war for example costs (so far) about a thousand times as much as putting robots on mars.

      Spending a very small amount of money on building a legacy isn't useless.
      [ Parent ]
  • Think of it like distillation (Score:4, Interesting)

    by Composite_Armor (1203112) on Wednesday December 19, @03:09AM (#21749038)
    Someone needs to look at this from a thermodynamic perspective. If there is in fact water on Saturn's moon, it must come from the surface. I am not sure why orbiting clouds of frozen water vapor (which i believe must have sublimated from the icy surface) are expected to contain Sodium. Thermodynamically speaking, species with low mass, and high activity (The light elements H, N, O, C, F) tend to undergo phase change before more heavy elements. These low density gases would exit into the moons atmosphere more readily than a sodium atom, even if the surface contained equal concentrations of all. (on wiki it says the atmosphere is Water, 4%Nitrogen, 3.2%CO2, and 1.7%CH4) makes sense so far, Also, i believe that if there was an ocean on this moon, the surface must be ice of near pure water. If water is going to freeze, it will do so first with minimal sodium. The sodium content in the ice will increase when the ocean concentration rises, eventually precipitating solid sodium compound when a saturation limit is reached. This only means that the outer shell of the moons frozen surface might be mostly clean ice I believe any sodium that could be detected in orbit must first diffuse to the surface through this concentration gradient. And then gain sufficient activation energy from the suns rays to enter the gas phase for an instant. I think these scientists could be looking for the wrong indicator. If we are searching for water, shouldn't we be searching for water? It is possible they have the right idea, but our instruments are not precise enough to measure such a small Sodium concentration. And i'm not sure the Seas of Saturn will follow our earthbound concepts of oceanography.
    • Re:How do you know? (Score:5, Informative)

      by wizardforce (1005805) on Wednesday December 19, @12:35AM (#21748260) Journal
      it's not sulfur, it's sodium and it's common enough in everything else that we've found in regard to rocks that sodium is a good bet for a relatively easy target for determining if there is indeed a liquid ocean under the surface. it's already suspected that ganymede has a liquid ocean under the surface with dissolved salts that cause the ocean to be conductive and conductive fluid interiors lend themselves to forming magnetic fields, thus it is also suspected that Enceladus has a similar ocean. Although in this case, the fact that Sodium wasn't detected doesn't fit the hypothesis that Enceladus has a liquid, saly ocean underneath.
      [ Parent ]
      • Re: (Score:3, Insightful)

        Maybe sodium it isnt so very soluable at such cold temps.
         
        Maybe, but thats something you could test here on Earth.
          • Re: (Score:3, Informative)

            solubilities are well know and tested for all common elements.
            • Re:Solubility at low temps (Score:5, Informative)

              by Ruie (30480) on Wednesday December 19, @02:38AM (#21748916) Homepage

              solubilities are well know and tested for all common elements

              Indeed ! Some tests are done more often then others.

              Solubility of sodium chloride (or calcium chloride) in water is commonly used to prevent it from freezing (application - cleaning sidewalks).

              The mixture of salt and water freezes at -21 Celsius = 272K or sooner, depending on purity. When salt water freezes it separates the salt which is why Antartic ice is not salty.

              From Wikipedia, the surface temperature of Enceladus is at most 145K, so it is likely that surface ice is pure and it is possible that the liquid water is kept liquid by tidal forces (water in motion freezes at lower temperature). One can even imagine how period crystallization and melting of water by tidal forces has separated out salt somehow.

              That said, sodium is extremely easy to ionize. To see that put a few salt crystals into gas or alcohol flame - it will turn yellow from the small quantity of sodium atoms that evaporated from the crystals. Thus, if liquid water was in direct contact with rock it would contain trace amounts of sodium which, when launched into space with the jet, will provide pronounced yellow line.

              What is possibly happening is that two ice sheets (pure H20) collide, melt ice with the pressure and spray the resulting water into space. TFA mentions two more possibilities - as well as a speculation that Sodium atoms could be frozen inside water crystals.

              [ Parent ]
    • Re:Assumption check, please (Score:5, Insightful)

      by CastrTroy (595695) on Tuesday December 18, @11:22PM (#21747840) Homepage
      Isn't Lake Michigan, along with all the other lakes, refilled every so often (on a geological time scale)? Seems to me that any salt that eroded from the rocks would eventually flow downstream and end up in the oceans. And it would get filled up again by rain water, which doesn't contain salt. That is my completely made up reason as to why lakes don't have salt, while oceans and seas do. Anybody know whether or not it makes any sense.
      [ Parent ]
    • Re:Assumption check, please (Score:5, Informative)

      by Cairnarvon (901868) on Tuesday December 18, @11:42PM (#21747962) Homepage
      Lake Michigan may be a freshwater lake, but it still contains salt. According to my internets, a cubic foot of Lake Michigan water contains about a sixth of an ounce of salt.
      [ Parent ]
    • Re: (Score:3, Funny)

      >"If you have a long-lived ocean, it's going to have salt in it,"

      Just like Lake Michigan?

      Yes, [palomar.edu] just like Lake Michigan.

      1 cubic foot of sea water evaporates it yields about 2.2 pounds of salt, but 1 cubic foot of fresh water from Lake Michigan contains only one one-hundredth (0.01) of a pound of salt, or about one sixth of an ounce. Thus, sea water is 220 times saltier than the fresh lake water.
    • Re:Assumption check, please (Score:4, Informative)

      by Jeff DeMaagd (2015) on Tuesday December 18, @11:56PM (#21748042) Homepage Journal
      A glacial lake is not the same as an ocean.
      [ Parent ]
    • Re:Obligatory (Score:5, Insightful)

      by Anonymous Coward on Tuesday December 18, @11:47PM (#21747990)
      Sodium existing as a requirement for life is not the issue here. I know this is slashdot and everything, but even TFS clearly states that the question is whether or not an ocean is the source of the water plumes that have been observed. It is the ocean we are looking for and it is the ocean that we believe is an indication of possible life.
      You may still take offense to the assumption that water is required, but when millions, nay, billions of dollars are on the line at NASA, you can be sure that greater and brighter minds than you or I have taken all the considerations and the great majority of scientists continue to believe that large bodies of liquid water are sufficient if not necessary conditions for life.
      Furthermore, if there is life, but not as we know it, then it is nigh unto impossible for us to begin looking for it. The most resources must necessarily be used in a manner which has the highest chance for success, and the small odds of finding life as we know it still compare favorably to the negligible odds that we find life as we do not.
      [ Parent ]
    • Re:Obligatory (Score:5, Informative)

      by Telvin_3d (855514) on Tuesday December 18, @11:51PM (#21748008)
      Who said anything about life needing sodium? The only real assumption going on is that life is more likely to occur in a liquid environment. Up until now, they signs have been that there was a liquid environment present, and as such it was a good place to look for life. Better than the alternatives at least. Now, the new research calls into question the existence of the large body of liquid that was thought to exist. So, if there is no liquid, the chances of life existing are lower and the reason for priority missions goes away.
      [ Parent ]
    • Re: (Score:3, Insightful)

      How can this be modded insightful? The absence of water suggests it is less likely to support life. How can you (and clearly a few mods) misread a summary? No one is arguing either that: a. Sodium is required for life or even b. That water is required for