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Space Science

Lake On Titan Winks From a Billion Kilometers Away 139

Posted by timothy
from the next-time-send-chocolate dept.
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."
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Lake On Titan Winks From a Billion Kilometers Away

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  • Thats what I call it when it doesn't come out as ass gas.
  • billion kilometers (Score:5, Interesting)

    by g0dsp33d (849253) on Thursday December 17, 2009 @09:57PM (#30483006)
    Its called a terameter. What is the point of the metric system if you don't use the other scales?
    • by Anonymous Coward on Thursday December 17, 2009 @10:06PM (#30483050)

      Mod parent +1E0 Informative but Pedantic.

      • I think ‘terameter’ (or Tm in short) sounds cool.

        I think we should start to expect from others, to know, what a Tm, a Gm, a Pm, etc, are. I will certainly, from now on. :)

    • by selven (1556643) on Thursday December 17, 2009 @10:10PM (#30483082)

      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"

      • by g0dsp33d (849253)
        Actually I might place more trust any of those. They have the sound of a extremely quirky scientist (1/2 NASA still uses miles, remember). Especially with decimal places.

        A billion kilometers sounds like it went through a news source and was dumbed down for someone who doesn't understand powers of 10 (eg That's a one followed by 12 zeros!).
      • Re: (Score:3, Informative)

        by stuffman64 (208233)

        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.

      • by dsoltesz (563978) <deborah.soltesz@gmail.com> on Friday December 18, 2009 @12:14AM (#30483826) Homepage Journal

        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.

      • by Herve5 (879674) on Friday December 18, 2009 @03:57AM (#30484722)

        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 ;-)

        • by bokmann (323771)

          Had it really happened by then? If it hadn't been observed, wasn't the lander really a 'Schodinger's cat', although in a really really big box?

          • You are raising a very interesting question, at least for the average engineer I am :-)

            What you are suggesting is, while Schrödinger was dealing with microscopic events (the cat's box was explicitly only an analogy), one may turn it large scale by replacing the request for isolation by a request for distance only.

            Now, I'm not sure an actual quantum physicist wouldn't answer you that because of the presence of possible alternate observers, the Huygens module quantum state probably would have to collapse

    • Re: (Score:3, Informative)

      by BadAnalogyGuy (945258)

      Depends on whether those are British billions or normal billions.

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

      • Re: (Score:1, Informative)

        by Anonymous Coward

        Exactly; if they used a metric prefix, there would not be that ambiguity.

      • by g0dsp33d (849253)
        Its 1024 ^ n. Everyone knows that!
      • by mike2R (721965)

        Depends on whether those are British billions or normal billions.

        Thankfully the British billion is well and truly dead now.

    • Re: (Score:2, Funny)

      by Tablizer (95088)

      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!"
           

    • Re: (Score:1, Funny)

      by ozmanjusri (601766)
      Its called a terameter.

      A terameter is a tool for measuring teras.

      A terametre is a unit of distance.

      • Re: (Score:2, Informative)

        by Anonymous Coward

        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.

        • Re: (Score:2, Funny)

          by ozmanjusri (601766)
          Both are acceptable.

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

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

        • by mqduck (232646)

          I'm afraid you are being pedantic. Both are acceptable.

          If both are correct, it's not really pedantic, is it?

          • I'm afraid you are being pedantic. Both are acceptable.

            If both are correct, it's not really pedantic, is it?

            That's pretty pedantic.

    • Re: (Score:3, Funny)

      by ctmurray (1475885)

      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.

    • by besalope (1186101)
      Why use meters at all? It's in space, it should be measured in AU (astronomical units).
    • by pitchpipe (708843)

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

      Plain ol' familiarity. Same reason that I would say that I weigh 90 kilograms instead of 0.09 megagrams. Well, maybe that and what it implies. :-O

    • Re: (Score:3, Insightful)

      by Alarindris (1253418)
      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.
      • by g0dsp33d (849253) on Friday December 18, 2009 @12:32AM (#30483898)
        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.
        • Re: (Score:3, Insightful)

          by Alarindris (1253418)
          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.
          • by selven (1556643)

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

            At least you don't have to memorize the names 3 times, once for distance (inch, foot, mile, etc), once for mass (ounce, pound, etc) and once for volume (fluid ounce, pint, gallon, etc).

        • by euxneks (516538)

          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.

          True, however, it's best to often represent a measurement in terms of what people already know. I know roughly how long it takes me to get through 1 km, but there is still the calculation, however quick, of changing a terameter into something I would be able to relate to easily, which is a billion km.

        • by lewiscr (3314)

          I would bet that less than 1% doesn't know what a Tera means.

          Of course we know what it means. 2^40.

      • by DoninIN (115418)
        The point of the metric system was for a bunch of pretentious jerks, including the french, to re-invent the wheel, then a bunch of pointy-headed science types, who loved it's utility for things like physics and... Well probably just that. Convinced the world it was a good idea to "switch" so now half the world has two or three types of tools, trillions of dollars have been wasted on the pointless duplication of hardware that perfectly functional, and the perfectly functional and in some ways superior for th
    • It's called scientific notation. Nobody really uses metric prefixes.

    • Re: (Score:2, Interesting)

      by noidentity (188756)
      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"

  • How do they know it's methane, couldn't it be any liquid?

    • by JoshuaZ (1134087) on Thursday December 17, 2009 @10:11PM (#30483090) Homepage
      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 [wikipedia.org]. 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.
      • by daveime (1253762) on Thursday December 17, 2009 @10:20PM (#30483168)

        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.

        • Re: (Score:1, Informative)

          by Anonymous Coward

          The text parent is paraphrasing belongs to 2010: Odyssey Two, directed by Peter Hyams. No Kubrick around.

        • by jo_ham (604554)

          Although to be pedantic, methane doesn't smell.

          The purest farts are silent, and not deadly, unless lit.

    • by zoom-ping (905112)
      Spectrum analysis? Didn't RTFA.
    • How do they know it's methane, couldn't it be any liquid?

      At that temperature, anyway. It can't be water.

  • 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.

    • by CheshireCatCO (185193) on Thursday December 17, 2009 @10:38PM (#30483278) Homepage

      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.

    • Re: (Score:3, Informative)

      by dumuzi (1497471)
      The methane [spaceref.ca] is believed to come from geological processes and not from life.
    • by pclminion (145572) on Thursday December 17, 2009 @10:51PM (#30483344)

      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.

      • In addition to the hydrocarbons, there is quite a bit of nitrogen available on Titan that gets fixed into a wide variety of molecules by UV radiation and cosmic rays in the upper atmosphere. It has been suggested that life could make a go of it on Titan with ammonia, nitriles, azides, and amines to provide reactivity. It would have to be a form of biochemistry that treats oxygen as a trace element, but the variety of reactive species you can form with just C,H, and N might be enough to substitute for mos
      • 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.

        Carbon in chemical combination with helium would be exceptionally interesting. Unfortunately, what we have here is carbon and hydrogen in the form of methane [wikipedia.org] and ethane, a combination that would hardly raise an eyebrow except for the observation that it's in liquid form. If it were frozen solid like the tonnes of water ice on Titan, things would look much less likely for any sort of complex chemistry. As it is now there are at least some possibilities.

      • Re: (Score:2, Informative)

        by hughperkins (705005)

        > 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

    • Titan life bleak. (Score:4, Insightful)

      by tjstork (137384) <todd.bandrowsky@gm a i l.com> on Thursday December 17, 2009 @11:32PM (#30483586) Homepage Journal

      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.

      • About Drake’s equation: Obligatory xkcd [xkcd.com].

      • Re: (Score:3, Informative)

        by Shooter6947 (148693)

        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

      • Venus has too much carbon.

        No more than Earth has. The problem with Venus's surface is that it's just too hot and it has lost its water. The fact that the carbon (dioxide) is more in the atmosphere than Earth is a by-product of these facts.

        Mars is missing nitrogen.

        It's not clear you need much and I don't think Mars actually lacks nitrogen in particular. It's just quite chilly and has a thin, thin atmosphere. It lacks everything, really.

        You seem to have defined "habitable" as "just like Earth", which yields predictable results. The more generally accepte

      • by molo (94384)

        Mercury is a big metal blob? WTF? Its a rocky planet.

        -molo

        • Mercury has a large iron core. Larger than a small planet should, in fact, have. This doesn't particularly alter the surface composition (which is rocky), but it can be fairly characterized generically as "metallic".

          "Blob" however is silly.

      • by Hatta (162192)

        it may well turn out that we are certainly alone in at least a 100 light year radius.

        Which is still pretty small on the scale of the galaxy.

    • Due to the frigid temperatures on Titan, scientists are not very optimistic about finding life there; without the heat input of the sun to speed up chemical reactions, it would take an incredible amount of time, if ever, for even the simplest structures to develop.

      • by Herve5 (879674)

        indeed the reason for the Cassini/Huygens mission over there was to analyse what was called a "frozen Earth" at the prebiotic stage.
        Titan's size and atmosphere thickness is definitely comparable to ours (and the only one in the solar system), it just never got the necessary energy to start things up...

  • by JoshuaZ (1134087) on Thursday December 17, 2009 @10:04PM (#30483036) Homepage

    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 [wikipedia.org] http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=44033 [esa.int]) 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.

    • Re: (Score:3, Informative)

      by Tablizer (95088)

      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.

    • by dmomo (256005)

      > Unfortunately, if there is any life, it is almost certainly microbial. So no one is appreciating the view from the planet.
      UNFORTUNATELY? Uggh. I'd call it a relief. I'm quite happy here on Earth with no natural predators. Sure, it's just because we humans taste aweful, but aliens may have a different sense of taste.

    • Saying that Huygens "wasn't much" and "was just a part of the larger Cassini mission" is pretty misguided thinking and borders on insulting the scientists and engineers who put this amazing probe together, IMHO.

      Are you saying that designing a probe that survives, dormant, for almost 7 years in interplanetary space and then turns on perfectly "isn't much"? Are you saying that making a fully-autonomous descent and soft landing on an outer planet's moon and sending back a stunning image of the surface "isn

  • The picture, even in "full resolution" is fuzzy. It reminds me of the original Quake logo. Considering that our atmosphere has strange phenomena causing glowing orbs that can be seen from space, I would see this "proof" as suspect.
    • Re: (Score:3, Insightful)

      by MichaelSmith (789609)

      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.

    • Re:Proof (Score:4, Informative)

      by JoshuaZ (1134087) on Thursday December 17, 2009 @10:18PM (#30483152) Homepage
      This image was taken by Cassini, the US probe currently orbiting Saturn. http://www.nasa.gov/mission_pages/cassini/multimedia/cassini20091217.html [nasa.gov] 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.
    • by Tablizer (95088)

      I suspect it merely looks fuzzy because of haze rather than distance or camera movement. Even close up, the photos of the atmosphere usually appear fuzzy or hazy clear back to the Voyager days. Its atmosphere extends pretty high into space because of low gravity.

      • by g0dsp33d (849253)
        Its not really a "camera", it does have a CCD, but apparently it uses diffraction grating and a mirror rotating along a single plane to make images. My guess is that this allows super-accurate mapping of light frequencies, but hurts the resolution. Also at this kind of distance the slightest imperfections in the lens would have much bigger impact, as would uneven gravitation fields. I just kind of expect clearer images from NASA by this point (especially after the upgrades to Hubble). Dually so for "proof".
    • by grcumb (781340)

      The picture, even in "full resolution" is fuzzy.

      That's because Titan wasn't winking at Earth. He was winking at Venus, who is, like, way hotter.

  • Fossil Oxidisers (Score:3, Interesting)

    by MichaelSmith (789609) on Thursday December 17, 2009 @10:12PM (#30483104) Homepage Journal

    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?

    • Re: (Score:2, Funny)

      by BadAnalogyGuy (945258)

      Frozen Nitrous Oxide anyone?

      Pssshh. Don't make me laugh.

    • by stoicio (710327)

      You actually don't need an oxidizer.

      If you just take the methane, and a big solar reflector, you should be able to
      cook the methane molecules (like ants under a magnifying glass).

      Then use the expansion to drive turbines on zero g.
      Transmit the energy back to Earth or moon for storage and distribution.

      We wouldn't need to use any energy resources from Earth after that.

      Using the moons of Jupter or Saturn as gravitational generators would probably be more efficient though....

      • by JoshuaZ (1134087)
        This would require a lot more infrastructure than the OP's proposal. Far out at Saturn the amount of light you get is much less than you get near the Earth because of the inverse square law. Saturn is about 9 times as far away from the sun as Earth is. So Saturn has less sunlight by a factor of 1/81. That's a lot. That means that any solar based energy system would be very inefficient compared to building it just around near planets like Earth. Indeed, that's one major reason probes like Cassini (the probe
        • Re: (Score:1, Interesting)

          by Anonymous Coward

          Wouldn't that depend on if you were collecting the radiant energy from the sun?

          As I understand it, Saturn and Jupiter emit lots of blackbody infrared energy from their own gravity causing atmospheric friction events.

          Failing that, one could also utilize the tidal forces of the gas giant as an energy source, since even at it's distance from it's parent planet, the gravitational mass-energy of the system would be immense. (Saturn may be smaller than Jupiter, but it's no midget either. It's got plenty of mass.)

      • by Hatta (162192)

        Wouldn't it take as much (or more) energy to boil the methane as you would recover from the turbines? The laws of thermodynamics apply on Titan too.

    • Geologically, Sulfate is most likely as far as oxidizers are concerned. NOw in so far as reacting the two together, you'd have to have a very well insulated system that uses the reaction its self to bring the reactants to a high enoug htemperature that chemical reactions can take place efficiently. Then there's the problme of mining the materials: THe reaction probably doesn't give out enough energy to make mining Sulfate as an oxidizer energy efficient.

  • The Kraken! The name of a lake on the moon of Titan, no less.
  • The Winston Sea, the Niles Sea, or the Rumfoord Sea?
  • Fake. (Score:4, Insightful)

    by mopomi (696055) on Thursday December 17, 2009 @11:24PM (#30483526)
    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.
    • by Toonol (1057698)
      You joke, but if exogeologists ever got to a point where they were dictating major governmental policies, you bet they probably would need reigned in.
    • Or intelligent life on earth! Now that would be serious bullshit! ^^

      Your friendly dimensional overlord.

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