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Titan's Lakes of Methane and Ethane

Rob Carr writes "During the most recent Cassini fly-by, the surface-mapping radar spotted what appear to be lakes in the high northern latitudes of Titan. From the article: 'The channels have a shape that strongly implies they were carved by liquid. Some of the dark patches and connecting channels are completely black, that is, they reflect back essentially no radar signal, and hence must be extremely smooth. In some cases rims can be seen around the dark patches, suggesting deposits that might form as liquid evaporates.' At Titan's temperatures, water is a solid; the lakes would be comprised of methane and ethane. The fluids are different, as are the temperatures, but these lakes cement Titan's status in the solar system as the place with the most earth-like weather — except for Earth, of course."

53 comments

  1. No ethanol? by FST777 · · Score: 0

    Please?

    --
    Free beer is never free as in speech. Free speech is always free as in beer.
    1. Re:No ethanol? by Anonymous Coward · · Score: 2, Funny

      bring oxygen!

  2. Re:Grammar Nazi by Whiney+Mac+Fanboy · · Score: 1, Informative
    "is composed of" or "comprises"... not "is comprised of"

    You are correct, but:

    1) The meaning is quite clear.

    2) The American Heritage Dictionary sez:
    Even though careful writers often maintain this distinction, comprise is increasingly used in place of compose, especially in the passive: The Union is comprised of 50 states. Our surveys show that opposition to this usage is abating. In the 1960s, 53 percent of the Usage Panel found this usage unacceptable; in 1996, only 35 percent objected. See Usage Note at include.


    Let's get the slashdot editors to fix basic grammar & spelling before we start worrying about edge cases of grammar :-)
    --
    There are shills on slashdot. Apparently, I'm one of them.
  3. Re:Grammar Nazi by 192939495969798999 · · Score: 1

    Hmmm, me not know what you're talking about... Basic grammar & spelling has never been issues here. /ha

    --
    stuff |
  4. Spore! by NsOmNiA91130 · · Score: 1

    I think it'll be a while before we get any humans there anyway. Why don't we grow the moon, Spore-style?

  5. Re:Grammar Nazi by creepynut · · Score: 2, Funny
    Hmmm, me not know what your talkin' aboot... Basic grammer & spelin has never been issue hear. /ha
    Fixed:)
  6. Fluid by MichaelSmith · · Score: 5, Interesting

    I remember that when the Huygens probe landed there were lots of pictures of dark areas presumed to be lakes with channels leading into them from higher ground. But the probe landed close to a channel and didn't see any liquid.

    Later the consensus was that the channels seen from Huygens were dry channels left over from flows in the past.

    The evidence in this case seems to be the darkness (in radar) of the "lakes", which imply that we are seeing liquid Methane or Ethane. So why are these areas different from the Huygens landing site? It is in a polar area (gee I wish we had a second probe now) but most of the heat on Titan comes from internal sources anyway so having the sun close to th horizon won't make it much colder.

    In any event Arthur Clarke is looking more right then wrong at the moment, We should be on the lookout for a Methane Monsoon.

    1. Re:Fluid by Tablizer · · Score: 2, Informative

      I remember that when the Huygens probe landed there were lots of pictures of dark areas presumed to be lakes with channels leading into them from higher ground.....Later the consensus was that the channels seen from Huygens were dry channels left over from flows in the past. The evidence in this case seems to be the darkness (in radar) of the "lakes", which imply that we are seeing liquid...So why are these areas different from the Huygens landing site?

      The darkness in the areas where Huygens landed was photographic darkness, not radar darkness. I don't know if they used radar on the Huygens area yet. But the dark area near Huygens extended quite far so perhaps they've already radared that area and found it radar-light.

  7. Titan is amazing by GreggBz · · Score: 5, Interesting

    We are pretty certain it has liquid lakes, but it may
    have caves as well.

    We know so little about our solar system.

  8. It's cold, but there are no caribou by ssk77077 · · Score: 0, Offtopic

    I say we drill up there and pipe that methane directly into my Hummer's tank.

    Peak oil, ha, who cares?

  9. And the hand-wringers say there is no reason by popsicle67 · · Score: 1, Informative

    None at all to explore the solar system. We are wasting money that would be better spent feeding people who are too lazy too feed themselves. I just love democrats, I just got through being berated by my ex-mother in law for being excited about this story and space exploration in general. I guess she doesn't get that we'll have to move out there one day because this planet will be too crowded. She says people need to wise up and stop breeding so fast so we can achieve a stable population with zero growth. What say all of you? Do you wanna give up screwing so smarter-than-thou intellectuals will be comfortable? Just what I thought,Fat Chance.

    1. Re:And the hand-wringers say there is no reason by TapeCutter · · Score: 1

      Have you ever heard the term "family planning" or do you just keep screwing until someone shouts "I'm pregnant"?

      I was born the year after sputnik was launched and have lived through the history of space exploration, the hubble pictures are worth every cent. Space exploration has shown mankind that we all live on what Carl Sagan called a pale blue dot. It has also shown us that it is all we have got, it's our collective "bird in the hand".

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    2. Re:And the hand-wringers say there is no reason by Alexandra+Erenhart · · Score: 0, Offtopic

      sex != reproduction, since the birth control pill and even counting days.

    3. Re:And the hand-wringers say there is no reason by mcsnee · · Score: 1

      Yeah. Those stupid Democrats. Why, if it were up to Democrats, we never would have gone to the moon!

      Fortunately, we have a wise, fiscally responsible Republican administration in office--one that would never waste money entrusted to it by the taxpayers of this country on anything irresponsible.

    4. Re:And the hand-wringers say there is no reason by popsicle67 · · Score: 1

      Not Democrats, John Kennedy. To the chagrin of his own party he managed to keep his promise to get to the moon despite strenuous efforts to derail the program by democrats who were already mad about the tax cuts he pushed through. Read a history book sometime, it may open your eyes.

    5. Re:And the hand-wringers say there is no reason by Tablizer · · Score: 1

      I don't think it matters much. I expect that machines be smarter than us in a generation.

    6. Re:And the hand-wringers say there is no reason by Melllvar · · Score: 1

      If Kennedy was the only thing keeping the Democrats from KO'ing the moonshot/space program, then how come NASA's Houston command post is called Johnson Space Center?

      And listen, mac. Maybe you don't want him to be one, but that still doesn't change the fact that JFK was a Democrat. Not a single history book I've ever read attempts to claim otherwise. If you judged a President's party affiliation by how in sync he was with the rest of the gang, then this country hasn't had a Democratic President since Andy Jackson. That party has just never worked that way; remember what Will Rogers said?

      And I found a history article here that sez:

      Dealing with the origins of the Apollo program, Kay points to the lack of any direct, proven relationship between the failed Bay of Pigs invasion and Kennedy's decision to go to the Moon. He does, however, note that in early 1961 the new administration suffered one blow after another, including Gagarin's first manned flight. The author also explains how, for once, the White House and Congressional leadership were in agreement. This gave the Moon program powerful political momentum that allowed it to survive the inevitable crises and loss of Congressional and public enthusiasm.

      So if Congressional favor for the space program eventually waned, it was more a reflection of growing voter cynicism in general than a knee-jerk Democratic Party hatred of all things space-related. Such an attitude clearly wasn't there at the beginning; and with a full five years of post-Kennedy full Democratic control of the government, you'd think they would have gotten around to shutting the program down sometime, if they'd really wanted to.

      In fact, the (Democratic Party nominated) Kennedy-Johnson ticket campaigned on a pro-space platform, and against the Eisenhauer-Nixon Administration's (unjustifiably) perceived ineptitude at it -- if only as a sideshow to the "Missile Gap" Big Dog issue of the 1960 elections.

    7. Re:And the hand-wringers say there is no reason by popsicle67 · · Score: 1

      It's a fact that we will be dumber than the machines that we use. I don't se it taking more than 5 years though. Right now our only edge is imagination, and from what I see that is becoming a rare commodity.

  10. Just throw a rock at it by Anonymous Coward · · Score: 0

    and see if there's a splash.

    1. Re:Just throw a rock at it by CogDissident · · Score: 2, Funny
      And god help you if that rock strikes a spark against another one.

      WHOOM! Oops, half the planet is on fire...

      Yes, I know that it wouldn't burn without oxygen in the atmosphere, but work with me here people.

    2. Re:Just throw a rock at it by rah1420 · · Score: 1

      Arthur C. Clarke noted this in his book "Imperial Earth."

      (Imperfectly quoted) "On Earth, they light a jet of hydrocarbon and let it burn in the oxygen atmosphere. Here, we light a jet of oxygen and let it burn in our hydrocarbon atmosphere."

      Pretty good book.

      --
      Mit der Dummheit kämpfen Götter selbst vergebens.
  11. Re:Grammar Nazi by 19061969 · · Score: 1

    Huh, you grammer looser...

    Oh, btw, just in case a mod thinks this is a flame: ;-) - that's a wink meaning that I'm joining in on the joke. Sheesh! The things you have to do to for post-modern irony!

    --
    bang goes my karma... again...
  12. we can have zero population growth by r00t · · Score: 1, Troll
    That's 2 or 3 surviving children, on average, where "surviving" really just means that they go onto reproduce and thus have families included in the average. Castration and death are equivalent.


    So how is this:

    At age 3, we execute the kids that can't walk and talk. At age 7, we execute the kids that can't read and do basic math. At age 11, we execute the kids who can't do algebra, geometry, 10 sit-ups, 2 pull-ups, 3 push-ups, a quarter-mile run, enough vision for safe driving, and able to carry out a phone conversation. At age 13, we execute the kids who are unable to do basic statistics, basic economics, reasonable analysis of common contracts (credit card agreement, DSL agreement, home lease, car loan...), or any of the age 11 requirements. Also, at any time prior to having children, we execute people for diabetes, blindness, significant asthma, etc.

    Like that? It certainly pushes evolution in a nice direction. It changes out fitness evaluation function to once again strongly disfavor the sick and feebleminded, rather than favoring the welfare mom.

    1. Re:we can have zero population growth by Philomathie · · Score: 0

      While I have to agree with you that your way is the "logical" way, it is certainly not the humane way.

    2. Re:we can have zero population growth by Tim+C · · Score: 1

      It's not even the logical way. Arbitrary measures risk disposing of people with a great talent or potential who otherwise do not make the cut.

    3. Re:we can have zero population growth by AdmiralWeirdbeard · · Score: 1

      Nah, I like our current model of selecting women with hips too narrow to bear children and increasing survival rates for terminal illness such that everybody can survive long enough to pass on genes for early onset cancers, diabetes, effective blindness, and all the other wonderful things we have developed once we started living past 35.

      Seriously tho. I'm the only person in my circle of friends with 20/20 vision. And none of them have light prescriptions. None of them can drive without their glasses. how fucked up is that, evolution?

      --
      Come read my stupid blagablog. Rants and Giggles
    4. Re:we can have zero population growth by Anonymous Coward · · Score: 0

      sign me up!

    5. Re:we can have zero population growth by PateraSilk · · Score: 1

      > Seriously tho. I'm the only person in my circle of friends with 20/20 vision.
      > And none of them have light prescriptions. None of them can drive without their
      > glasses. how fucked up is that, evolution?

      This is a fallacy that many people like to use as a proof of the (genetic) degeneracy of these End Times. If someone could show me statistics that prove that bad eyesight (or another supposed modern degenerate trait) was actually selected against in a way that affected breeding populations before the advent of modern medical science, then I'll agree with this take on evolution. I'm pretty sure that people with bad eyesight back in the day just coped, and went about their lives, because they had no other way to imagine things being.

      --
      Danke tres mucho, tovarishch.
    6. Re:we can have zero population growth by AdmiralWeirdbeard · · Score: 0, Flamebait

      Uh... care to support your claim that it *is* a fallacy?
      we could just play the "no the burden of proof is on *you*" game back and forth, wouldnt that be fun.
      Do I have proof? obviously not. Nor do you, or you'd have included it rather than just being a trumped up negative nancy.
      but...
      I am, however, equiped with powers of reasoning, so I'll just work them a bit. If you're basically blind, you're more likely to trip and fall, and therefore more likely to be injured walking around. You're less likely to see the sabre-tooth tiger crouching behind that bush, or the poisonous snake or spider siddling up next to you.
      I'd say that increased risk of accident and predation might constitute pressures capable of negatively selecting the trait of bad vision in human populations before modern times.

      Also, way to go, demanding statistical proof for the contrary notion, while supporting your own theory with "I'm pretty sure that..."
      You're pretty sure are you? Well, fanFUCKINtastic. I'm equally sure that 'they just coped with it' is the lamest explanation of anything ever. They could 'just cope with it' and still not see well enough to get killed before procreating.

      Now, if there were somethign that showed a genetic correlation between bad eyesight and say, hotness, which is clearly selected for evolutionarily, this would be a different thing. but all other things being equal, an allele that makes it more difficult to reach procreation age and so procreate, than a different allele for said trait, will, to some extent be selected against.
      If you would like to explain how bad eyesight is survival neutral with good eyesight, I'm all ears. Tho, as hinted at earlier, the "they'll just cope with it" argument is flawed at best.

      --
      Come read my stupid blagablog. Rants and Giggles
    7. Re:we can have zero population growth by kimvette · · Score: 1
      Seriously tho. I'm the only person in my circle of friends with 20/20 vision. And none of them have light prescriptions. None of them can drive without their glasses. how fucked up is that, evolution?


      I don't know, let's take a look at the first thousand years (in Biblical terms) shall we?

      Genesis 27
      1 It happened, that when Isaac was old, and his eyes were dim, so that he could not see, he called Esau his elder son, and said to him, "My son?" He said to him, "Here I am."

      Hmm, it seems that right from the get-go things were all screwed up. Is evolution true? If so we'll never know, but in a couple hundred generations if humanity develops wings or loses the little toe then eventually our distant descendents will know, but we (our current generation) never will. If the creationism is right we'll all find out sooner or later. In the meantime making fun of evolution on such a basis is just, shall we say, flawed, since the "evidence" for creation suggests that humanity was flawed from the earliest of days. You can't blame poor eyesight on entropy on the basis of genetics breaking down any more than one can with absolute certainty prove evolution or disprove the existence of God.

      Nice troll, though! ;)
      --
      The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
    8. Re:we can have zero population growth by AdmiralWeirdbeard · · Score: 1

      Um, I'm not entirely sure what you're really saying. I was not advocating creationism, nor attempting to weaken evolution. I was merely pointing an area in which i believe we have eliminated a mechanism of negative selection. Namely: if you cant see the bison about to run you over, you dont progress to passing on the genes that caused you to be unable to see said bison.
      I was not "making fun" of evolution, I was personifying evolutin to join me in making fun of humanity.
      and yes, bad eyesight has been around for a long time, i was commenting on the prevalence of really bad eyesight, like my friends literally are not allowed to drive without glasses, or literally cannot tell brown from green, etc.
      so yeah... not really a creationist troll... not really sure what you were responding to...

      --
      Come read my stupid blagablog. Rants and Giggles
    9. Re:we can have zero population growth by PateraSilk · · Score: 1

      One fallacy here is that humans have been susceptible to sabre-tooth tigers until the near past. (Haha, that's a joke.) If we look at humans as a wild population, non-norm eyesight might be a detriment. But we're talking about humans in their natural setting, that is, within bands or tribes that have division of labor.

      Let's look at the breakdown of possible eye problems. Presbyopia, or "far-sightedness", precludes easy detail work because the eye cannot focus closely but excels at focuses near infinity. Myopia, or "near-sightedness", precudes distance vision but provides magnified detail vision. Those with neither problem have no specialization but no handicap.

      So, let's construct a thought-experiment, similar to your thought-experient of tigers and spiders, to illustrate the point. Those with presbyopia were selected for jobs within the social structure that required such eyesight: hunting, fighting, etc. Those with myopia were selected for jobs that didn't require perfect distance vision: butchery, making arrows, making armor, or working as scribes. Those with normal vision could do either, which gave them a slight advantage.

      However, myopia and presbyopia cancel each other out when mixed, so any given person could have children with any range of eyesight. If an individual excelled at his or her role within the group, near- or far-sighted, he or she would have an excellent chance of progeny, who would have a decent chance of decent eyesight. If not, they could always specialize as their progenitor had. Plus, many times vision problems do not manifest until puberty, which would keep the children so afflicted plenty of time to avoid spiders and tigers until they were mature enough to learn coping skills.

      This is why I think that conflating eyesight with diabetes or cystic fibrosis, two diseases that definitely will kill in childhood if not infancy, to be specuous. But even those two diseases, which on the face of it look like genetic dead ends, may provide adaptations for surviving famine and tuberculosis. Natural selection is never easy to tease out.

      Is that better?

      --
      Danke tres mucho, tovarishch.
    10. Re:we can have zero population growth by AdmiralWeirdbeard · · Score: 1

      but we're also talking about the survival rate of a given allele over competitor alleles for a given trait, which means that we're speaking about individuals. yes, individuals agregated over a mating population as whole, but individuals nonetheless. One given allele may make individuals with it more societally valuable, but that does not really inform their status of biological fitness. So the presyobic would make better guards for the fort than the myopic. That in no way aids them in avoiding life-threatening dangers that require near-distance focus. I realize that humans are social animals, and we do things like, making sure blind johnny has someone with him to keep him from walking off the ramparts, but that does not undo blind johnny's predisposition to walking off the ramparts.
      Even if you think that the negative pressure on selection was outweighed by other social factors (I'm neutral on this judgment, btw) removing whatever negative pressure there was *will* have the effect of shifting the balance away from negative selection toward positive selection on a that given allele.

      Natural selection is, of course never easy to figure out. I maintain, however, that it is in no way specious reasoning to say that over the whole population, higher % with perfect vision through correction, will avoid a higher percentage of mortality that can be attributed to poor vision, and increase the % of the breeding population that is sensitive, in terms of survivorship, to poor vision. Given my assumption that the parts of the breeding population sensitive to mortality as a result of poor vision are those with poor vision, i.e. that people with poor vision get themselves killed more than they get people with perfect vision killed, this will lead to a larger presence in the resulting generations of alleles responsible for poor vision. Obviously this assumption could be debated, thats why its an assumption, not a "fact."

      I know you would like to argue societal roles of people manifesting poor vision vs perfect vision, I am, however more concerned with the genetics of it. There are plenty of ways to blind yourself in childhood and still pass on genes for 20/15 vision.

      --
      Come read my stupid blagablog. Rants and Giggles
    11. Re:we can have zero population growth by PateraSilk · · Score: 1

      I hear what you're saying. However, IMHO, from what I've read, a trait that confers a genuine disadvantage on individual members will be weeded out rather quickly in a population. Those that confer slight disadvantage or are survival neutral will persist. In modern society, granted, our superior medical care will convert many afflictions to survival neutral, but the prevalence of things like cystic fibrosis or Tay-Sachs are much much less than simple myopia or presbyopia. In other words, the prevalence of bad eyesight is much much higher than could be supposed if it was truly deleterous.

      In other words, the genes for bad eyesight had to come from somewhere, i.e., the population that existed before modern science. For bad eyesight to manifest itself at the level it does in modern populations, either it was prevalent before or it is controlled by a single (or very few) mutation(s) on one (or very few) susceptible gene(s).

      I think it's possible that another modern invention, affluence, may have made it more obvious that the population has a range of eyesights. Before a certain time (maybe WWII? Maybe the 1920s?) eyeglasses were too expensive to be readily available to the masses, or were expensive enough to warrant their use only when absolutely necessary. After incomes went up, or manufacturing costs went down, everyone could afford them and suddenly a bunch of people had glasses. OMG!! EVERYBODY PANIC!! ; )

      --
      Danke tres mucho, tovarishch.
    12. Re:we can have zero population growth by PateraSilk · · Score: 1

      Uh, Admiral Weirdbeard wasn't trolling, and he wasn't talking about entropy or any other creation science red herrings.

      Yes, you can mod me "Troll" for this.

      --
      Danke tres mucho, tovarishch.
    13. Re:we can have zero population growth by AdmiralWeirdbeard · · Score: 1

      slight disadvantage is obviously what I was talking about.
      poor eyesight is obviously nowhere near negatively selected trait as cystic fibrosis, or that condition, whose name i cannot remember where kids age to like 100 before they turn 10.
      My point was merely that we have removed the negative-feedback cycle which contributed to whatever equilibrium point poor eyesight existed in the population.

      --
      Come read my stupid blagablog. Rants and Giggles
    14. Re:we can have zero population growth by r00t · · Score: 1

      It's no different from them randomly not being born, unless you have reason to believe that genes for "great talent" or "potential" are significantly associated with traits that will cause someone to not make the cut.

      It's rather clear that the opposite is true, unless you have an inverted idea of "great talent" or "potential".

  13. Re:Oh, great! by MobileTatsu-NJG · · Score: 1

    "How long till Bush tries to stick a goddamned american flag on that rock ?"

    Though I get the political commentary here, but wouldn't we all be happy if Bush funded a mission to stick a rock on that moon?

    --

    "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

  14. What Methane? by p33p3r · · Score: 0, Interesting

    I say that the oil companies will launch an exploratory probe and then report that no methane exists. Therefore the gas prices will remain at their artifically exorbitant high levels.

  15. Re:Oh, great! by p33p3r · · Score: 0

    The W would first determine that weapons of mass destruction exist and then send an expeditionary military force to promulgate a regime change sympathetic to American oil interests.

  16. Liquid suggested as vital component of prelife by weemattisnot · · Score: 2, Interesting
    I just recently finished a fascinating article in "Artificial Life II" from the Santa Fe Institute in the Sciences of Complexity. The author used Cellular Automata (think Conway's game of life) to show that complex structures only occur when the rules of the Cellular automata fall within a certain range of the possible sets of rules.

    The range works like this (this is over-simplified btw):

    • If the rules tend too much towards the "quiescent state" (think all the cells turning black in conways game of life), then the automata is too simple, there is no way for any self-replicating order complex or even simple to develop.
    • If the rules don't tend towards the quiescent state enough, then the automata is too chaotic. Forms self-interfere in too chaotic a way, and it is impossible for order of any kind to develop.

    While examining the data from the different automata with different rule sets, he noticed a "phase change" in the patterns of artifial life that came to be given the different rule sets, and found the complex/interesting "creatures" only would exist at around this phase change. He then went on to suggest that the origin of _real_ life may also only come to be where there is the right balance of order and chaos, and suggests that the phase changes seen in physical systems (solid/liquid/gas) are analagous to the rule sets in the cellular automata (Solids = Order, Gasses = Chaos*, Liquids = Right Balance). Finally this puts forward my hypothesis that life may only require liquids to form (i.e. perhaps it's not necessary to have liquid _water_, but just liquid something).

    * The chaos of gasses and their simultaneous lack of informational complexity: Think about how with gasses: while there are shitloads of molecules flying about at insane speeds, the overall behaviour of the gas can be really simply summarized with a high degree of accuracy -- e.g. Pressure*Volume=Temperature

    Carl Sagan in Cosmos suggested that some where out there, there might be some sort of hard-wired life (e.g. an electronics based life that is a solid), but the theories I mentioned here would suggest that the solid-life forms would not come about (at least not with out an intermediate period of development in a liquid). Finally, it is interesting to think about how life even once it left the ocean has maintained its base in liquids. Are there any examples of life that are more solid than liquid?

    Hmmm..thinking I might get modded off-topic, but I think this is interesting and relevant enough to bring up.

    The article was titled "Life at the Edge of Chaos" and its by Christopher G. Langton.

    1. Re:Liquid suggested as vital component of prelife by Anonymous Coward · · Score: 0

      Are there any examples of life that are more solid than liquid?

      If we can make computers that replicate (on their own), there might be. But then I understand that lots of water (among other solvents) is used by the semiconductor industry in the production of the functional components of computers. So it seems likely liquid in great amounts at certain stages would remain necessary.

    2. Re:Liquid suggested as vital component of prelife by Anonymous Coward · · Score: 0

      Life also requires -instructions-, not just chaos and energy differential.

    3. Re:Liquid suggested as vital component of prelife by weemattisnot · · Score: 2, Insightful

      The article arguing that the ability to pass on information happens spontaneously given a system with a certain ratio of chaos and order. Unless I misunderstand what you're saying, this passing on of information is analogous to the "instructions" that you mentioned in your post.

  17. Strange comment on the NASA site by rotenberry · · Score: 1

    On the Cassini-Huygens Home page ( http://saturn.jpl.nasa.gov/home/index.cfm ) we read that:

    "These lakes appear to be filled with hydrocarbon liquids, possibly making Titan the only place other than Earth known to contain lakes."

    This statement is a bit misleading since there are lava lakes on both the Earth and on Jupiter's moon Io. The Earth's lava is primarily silicon, while Io's lava is primarily sulfur, but remember that on Titan water is considered a rock.

  18. Re:Grammar Nazi by Anonymous Coward · · Score: 0

    Who said he was Canadian?

  19. That's a pretty safe bet by dexter+riley · · Score: 1

    Finally this puts forward my hypothesis that life may only require liquids to form (i.e. perhaps it's not necessary to have liquid _water_, but just liquid something).

    Diffusion in solids is prohibitively slow. The common molecules that could form information-storing polymers are very, very insoluble in gases. That pretty much leaves liquids. I wouldn't say that life could never evolve without the benefit of liquids, but it could require timescales far longer than the current age of the universe.

    I highly recommend the book, "Life Beyond Earth" (the 1980 Gerald Feinberg version!) which discusses some exotic, but maybe not impossible ways that life could evolve (life in liquid hydrogen?)

    I myself make no predictions about life in plasmas, Einstein-Bose condensates, non-baryonic matter and so on, since my mother never let me play with them when I was a boy.