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Lake On Titan Winks From a Billion Kilometers Away

The Bad Astronomer writes "NASA's Cassini spacecraft took an image of Saturn's giant moon Titan earlier this year that serendipitously provides proof of liquid (probably methane) on its surface. The picture shows a glint of reflected sunlight off of a monster lake called Kraken Mare (larger than the Caspian Sea!). Scientists have been getting better and better evidence of liquid methane on Titan, but this is the first direct proof."

37 of 139 comments (clear)

  1. billion kilometers by g0dsp33d · · Score: 4, Interesting

    Its called a terameter. What is the point of the metric system if you don't use the other scales?

    --
    lol: You see no door there!
    1. Re:billion kilometers by Anonymous Coward · · Score: 5, Funny

      Mod parent +1E0 Informative but Pedantic.

    2. Re:billion kilometers by selven · · Score: 3, Informative

      Just be glad it's not "Lake on Titan Winks from 621 Million Miles Away"

      Or "Lake on Titan Winks from 4.97 billion Furlongs Away"

      Or "Lake on Titan Winks from 10^-12 Diopters Away"

    3. Re:billion kilometers by BadAnalogyGuy · · Score: 3, Informative

      Depends on whether those are British billions or normal billions.

      http://www.askoxford.com/asktheexperts/faq/aboutwords/billion?view=uk

    4. Re:billion kilometers by Tablizer · · Score: 2, Funny

      Its called a terameter. What is the point of the metric system if you don't use the other scales?

      That unit would scare away readers. "Yikes! A terameter-high terrorist!"
           

    5. Re:billion kilometers by stuffman64 · · Score: 2, Informative

      Even if Diopter was a proper measure of length (and it isn't), it would actually be 1/(10^-12 Diopter) as Diopter is the reciprocal of a focal length to measure optical power. Still, it's an interesting way of putting it.

      --
      --- At my sig, unleash hell.
    6. Re:billion kilometers by ctmurray · · Score: 2, Funny

      Its called a terameter. What is the point of the metric system if you don't use the other scales?

      Because then everyone would have to look up teramer and google would crash under the /. rush.

    7. Re:billion kilometers by Anonymous Coward · · Score: 2, Informative

      I'm afraid you are being pedantic. Both are acceptable. The "-re" suffix is an influence from French. If you look at French words for measuring devices as well as units of measure, you will understand this.

    8. Re:billion kilometers by ozmanjusri · · Score: 2, Funny
      Both are acceptable.

      Of course. And so is "1 inch = 25.4 millimeters"

      Let's face it, this isn't rocket science, is it?

      --
      "I've got more toys than Teruhisa Kitahara."
    9. Re:billion kilometers by Alarindris · · Score: 2, Insightful

      The point of the metric system is consistent units of 10, not the naming conventions. They prefixes are basically as arbitrary as 12 in = 1 foot, as no one speaks latin anymore.

    10. Re:billion kilometers by dsoltesz · · Score: 4, Informative

      No matter how you say it, it's wrong. It winks from 200,000 kilometers away. The rest of the distance was just data transfer.

    11. Re:billion kilometers by g0dsp33d · · Score: 3, Interesting

      It is generally accepted to try to use the prefix that will best keep the number of units between 1-999. More people might still speak parts of Latin if people used the correct terms. Also Slashdot is a technical crowd and I would bet that less than 1% doesn't know what a Tera means.

      --
      lol: You see no door there!
    12. Re:billion kilometers by noidentity · · Score: 2, Interesting
      Heh, reminds me of I think it was Enterprise episodes where they were talking of thousands and tens of thousands of meters from the ship. I kept wondering why they didn't say for example 3.5 kilomoeters, 20 kiliometers, etc.

      Just be glad the headline wasn't "Lake On Titan Winks From a Giga Kilomoeter Away"

    13. Re:billion kilometers by Herve5 · · Score: 4, Informative

      Actually it's one and a half hour away. At light' speed, I mean.

      I happen to have been tech resp. of the european Huygens probe that Cassini brought to Titan, and what I remember the most from the time of Huygens descent and landing years ago, is this feeling that all the active descent has *already* happened, while here on Earth we didn't yet have received the first bits of info, radiowave that were still into the travel.

      Indeed that was a very real way of measuring distance. Saturn definitely is not close...

      Hervé S. (now back on more conventional Earth observation spacecraft designs ;-)

      --
      Herve S.
    14. Re:billion kilometers by Alarindris · · Score: 2, Insightful

      That's my point, metric's usefulness is the math part. The prefixes could be called anything, they could be iimeter, imeter, meter, Imeter, IImeter, etc.

      That part you still have to memorize just like 5280ft in a mile.

    15. Re:billion kilometers by selven · · Score: 2, Informative

      Both work

      I, at least, prefer reducing the sheer number of irregular verbs out there.

  2. Where do the hydrocarbons come from? by BadAnalogyGuy · · Score: 2, Interesting

    Methane is an organic material. Organics are one of the key building blocks of life. In fact, it is one of many byproducts of life processes. An abundance of organic material bodes well for finding life (probably bacterial) on Titan.

    The question is whether life arose there on its own or was seeded by wayward asteroids and comets.

    1. Re:Where do the hydrocarbons come from? by CheshireCatCO · · Score: 4, Informative

      Methane is the precursor to organic molecules, in a more general sense, not the result of biological processes. When you're the simplest combination of carbon (what, the fourth most abundant element in the universe?) and hydrogen (the most abundant element), it's hard to argue that your existence requires biological processes. (Particularly as methane is found everywhere volatiles can be found in our solar system and outside of it.)

      Perhaps you're confused by the fact that methane on Earth is usually the result of biological activity? That's because in our peculiar atmosphere, methane can't survive long before oxidation.

    2. Re:Where do the hydrocarbons come from? by dumuzi · · Score: 3, Informative

      The methane is believed to come from geological processes and not from life.

    3. Re:Where do the hydrocarbons come from? by pclminion · · Score: 5, Interesting

      Methane is an organic material. Organics are one of the key building blocks of life. In fact, it is one of many byproducts of life processes. An abundance of organic material bodes well for finding life (probably bacterial) on Titan.

      I doubt it. "Organic" is an artificially created classification. It just means anything that is prevalently composed of carbon atoms. There happen to be a lot of carbon atoms in the universe, due to its relatively low atomic mass. There's also a ton of helium. It is not really surprising that these common elements might be found, in combination, in large quantities. We have large deposits of hydrocarbon here on Earth as well. Yes, these compounds are, according to our own definitions, "organic", and in fact originated from living matter, but we do not see organisms thriving in the deep oil wells.

      I do not see how an excess of methane would indicate the likelihood of finding "bacterial" life. What would the cell walls be composed of? It would have to be something like a lipid bi-layer, so that the membrane wouldn't just dissolve into the methane. But then, what's INSIDE the cell? Probably, it would be more hydrocarbons. These non-polar materials are ill-suited as stages for complex, biological chemical reactions. They cannot dissolve ions. Without soluble ions, hell, without soluble polar compounds, there isn't a whole hell of a lot of interesting chemistry that can take place.

      If we found tons of water that would be far more indication of the potential for life. Water has dozens of extremely unusual properties all of which make it conducive to life.

    4. Re:Where do the hydrocarbons come from? by pclminion · · Score: 2, Informative

      Lets try to find life that has nothing to do with the life we know and endure on this planet and would die if it tried to live amongst us.

      No. What you are saying is basically, "We should be looking for something we can't imagine." I'd like to point out that this is basically the same as saying "Let's find some shit," and doesn't help whatsoever in directing us WHERE we ought to be looking for life. If you want to find life, you need some kind of strategy to narrow down the billions of possible places to look to something that's likely to turn up some results. Looking for something that, by definition, you have no idea how to look for, is not a fruitful use of resources.

      Water, carbon, nitrogen, these are not rare materials in the universe. Chances are pretty good that if life could form from these materials here, it could form elsewhere. And we know WHAT to look for to recognize the signs of life as we know it. Only if we look long and hard, and find no signs of life as we know it anywhere in the measurable universe, should we turn to such vague propositions as "Let's look for something we can't imagine."

    5. Re:Where do the hydrocarbons come from? by hughperkins · · Score: 2, Informative

      > There's also a ton of helium. It is not really surprising that these common elements might be found, in combination, in large quantities.

      I don't think you'll find helium combining with anything much ;-) I think you meant 'hydrogen' :-P

  3. And given the possibility of life... by JoshuaZ · · Score: 4, Informative

    Prior to this, the main evidence that Titan might have liquid methane was based on the reflection of radio waves detected by the Cassini probe. In particular, there were discrepancies between what one would expect and what was observed in the percentage of reflection in the ELF range (about 2 to 30 Hz). This discrepancy suggests some form of boundary layer, such as a boundary between liquid and solid methane or between liquid methane and some other solid substance. There's also a lot of evidence for a large internal methane sea under the solid surface. We still know very little about Titan. We've only sent a single probe (Huygens) actually dedicated to investigating it. However, even Huygens wasn't much and was just a part of the larger Cassini mission. The next scheduled mission is the TSSM (Titan Saturn System Mission) (http://en.wikipedia.org/wiki/Titan_Saturn_System_Mission http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=44033) which will focus a lot more on Titan. Hopefully a lot of the mysteries about the moon will then be answered.

    Titan is routinely used as an example of a moon that might have life. Unfortunately, if there is any life, it is almost certainly microbial. So no one is appreciating the view from the planet.

    1. Re:And given the possibility of life... by Tablizer · · Score: 3, Informative

      The Huygens probe was actually designed to float in liquid in case it encountered a pond, lake, or ocean. It would have been interesting if it did, but alas it landed on just dry land (or at least frozen-solid land). However, the rocks (possibly water-ice) it imaged at the surface were rounded off, suggesting that they used to be embedded in liquid.

  4. Re:How do they know it's methane by JoshuaZ · · Score: 4, Informative

    We know that Titan has a lot of methane. The main reason is that the radiation it gives off is consistent with methane. In particular, we can use spectroscopy to confirm that the light given off is highly consistent with methane reflecting light from the sun. See http://en.wikipedia.org/wiki/Spectroscopy. We have evidence for the methane nature both in the visible range, infrared range and certain other ranges that is consistent with methane and not much else. Moreover, methane is very stable and fairly common (as chemicals go) so even if we didn't have very good spectroscopic data, it would be the most likely guess.

  5. Fossil Oxidisers by MichaelSmith · · Score: 2, Interesting

    If it was possible to mine or drill for oxidizers under the surface of Titan, then you would have a complete energy economy.

    Frozen Nitrous Oxide anyone?

    1. Re:Fossil Oxidisers by BadAnalogyGuy · · Score: 2, Funny

      Frozen Nitrous Oxide anyone?

      Pssshh. Don't make me laugh.

  6. Re:Proof by MichaelSmith · · Score: 2, Insightful

    A bright light out around Saturn has to be the sun. So if your camera is not pointing at the sun it must be pointing at a reflection of the sun.

  7. Re:Proof by JoshuaZ · · Score: 3, Informative

    This image was taken by Cassini, the US probe currently orbiting Saturn. http://www.nasa.gov/mission_pages/cassini/multimedia/cassini20091217.html Issues in our own atmosphere thus could not impact this. And if you meant that Titan might have strange atmospheric behavior causing this, that's almost as unlikely. The size of this event is much larger than almost any weird atmospheric event (which are normally at most a few hundred meters large at the very largest, rather than many kilometers across. Moreover, this picture isn't the only data point. The data was consistent with specular reflection over all observed wavelengths (both visual and near infrared). So you would need to posit an extremely large event that happened to precisely duplicate what we'd expect to see in reflection. That's remotely possible, but not at all likely. There's never "proof" in science. Proof is for mathematics and alcohol. But this is very strong evidence for the presence of a large body of liquid methane on the surface of Titan.

  8. Re:How do they know it's methane by daveime · · Score: 4, Funny

    ALL THESE FARTS ARE YOURS. USE THEM WISELY, AND DON'T LIGHT ANY NAKED FLAMES.

    EXCEPT TITAN. ATTEMPT NO LANDING THERE, BECAUSE IT BLOODY STINKS.

    Filter error: Don't use so many caps. It's like YELLING. Yes, right, I'm sure Stanley Kubrick told Arthur C. Clarke the same thing when they were finalizing the screenplay. So now I'm reduced to typing a lot of mindless garbage just to get around the lousy Slashdot filter.

  9. Re:Liquid Methane Eh? by Tablizer · · Score: 2, Funny

    Where's the TMI mod when you need it?

  10. Re:Liquid Methane Eh? by ozmanjusri · · Score: 3, Funny
    Thats what I call it when it doesn't come out as ass gas.

    Read the name of the "lake", - Kraken Mare.

    It's just a big puddle of sea-monster piss, nothing exciting at all.

    --
    "I've got more toys than Teruhisa Kitahara."
  11. Fake. by mopomi · · Score: 3, Insightful

    We all know it's faked. Those slimy scientists will do anything to guarantee their funding for another year. Last year it was a decoupled lithosphere on Titan, now it's lakes of liquid hydrocarbons? Sure! Next it'll be seasonal rivers of liquid hydrocarbons, jets of water escaping from Enceladus, volcanism on Io, meteorites on Mars, people on the moon, etc., etc., etc. We really need to reign in these people.

  12. Titan life bleak. by tjstork · · Score: 3, Insightful

    The odds for life on Titan are bleak because it is so damned cold. How cold is Titan? Well, when your methane is liquid, as in, liquified natural gas, that's pretty damned cold. The other problem, I think, is a lack of oxygen. I think the basic blocks for life would be nitrogren, oxygen, hydrogen, carbon and I think a splash of sulfur, plus some form of energy. When you really think about it, life is basically a set of chemical reactions that go against the grain of entropy and produce a set of molecules that arrange things in a higher energy state. Like, the outcome of most dead things is to easily burn.

    Mercury is big metal blob and way too hot.
    Venus has too much carbon.
    Earth is nice.
    Mars is missing nitrogen.
    Jupiter / Saturn / Uranus / Neptune big hydrogen blobs.
    Pluto, other deep objects, are near absolute zero.

    Maybe Jupiter's moon Europa might luck out.

    But honestly, I would bet that if you included some terms in Drake's equation to allow for the probability of having all the elements in the right mix at the right distance from a star, then, it may well turn out that we are certainly alone in at least a 100 light year radius.

    --
    This is my sig.
    1. Re:Titan life bleak. by Shooter6947 · · Score: 2, Informative

      The other problem, I think, is a lack of oxygen.

      There's plenty of oxygen on Titan. The whole crust is made out of water ice. True there is no free molecular oxygen, but neither was there on Earth before about a billion years ago.

      As for life on Titan, the suggestion is that there might be an opportunity when the liquid water beneath Titan's 50-km-thick ice crust bubbles to the surface (a "cryovolcano"), or when a meteor impact leaves a patch of melted local bedrock (which is water ice, so the patch would be a lake). When liquid water from one of these sources combines with the organics in the atmosphere, who knows what happens. But it better happen fast -- the whole thing freezes over in 10^4 years!

  13. Re:Liquid Methane Eh? by Anonymous Coward · · Score: 2, Funny

    Way to explain the joke, asshole.

  14. Re:How do they know it's methane by Herve5 · · Score: 2, Informative

    indeed on Titan the ground rocks are constituted of almost pure water ice, and over there ice just will be rock-hard forever.
    The pebble on these Cassini-Huygens lander photos are ice: http://www.esa.int/SPECIALS/Cassini-Huygens/SEMEMY71Y3E_0.html (visible on the orange vertical image that is the "last photo" Huygens took once on ground)
    Hervé

    --
    Herve S.