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Enceladus "Sea" Mystery Deepens

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."

14 of 166 comments (clear)

  1. Sodium Depletion Due To... by haakondahl · · Score: 5, Funny

    ...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.

    --
    Don't trust anyone under thirty.
  2. Re:Assumption check, please by CastrTroy · · Score: 5, Insightful

    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.

    --

    Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
  3. Re:Assumption check, please by Cairnarvon · · Score: 4, Informative

    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.

  4. Re:Obligatory by Anonymous Coward · · Score: 5, Insightful

    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.

  5. Re:Obligatory by Telvin_3d · · Score: 4, Informative

    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.

  6. Waste of Money by mothlos · · Score: 5, Interesting

    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.

    1. Re:Waste of Money by Anonymous Coward · · Score: 5, Insightful

      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...

    2. Re:Waste of Money by rve · · Score: 5, Insightful

      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.

  7. Re:How do you know? by wizardforce · · Score: 4, Informative

    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.

    --
    Sigs are too short to say anything truly profound so read the above post instead.
  8. Informative to whom? by TapeCutter · · Score: 4, Informative

    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".

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  9. Re:Solubility at low temps by Ruie · · Score: 5, Informative

    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.

  10. Think of it like distillation by Composite_Armor · · Score: 4, Interesting

    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.

  11. Re:Moderator on Crack by GTMoogle · · Score: 4, Insightful

    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)

  12. Re:Moderator on Crack by APODNereid · · Score: 4, Insightful

    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?