Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Moon Science

Shadowed Lunar Craters May Be Coldest Spot In the Solar System 108

sciencehabit writes "Science reports: 'What's the coldest spot in the solar system? For now, that distinction belongs to permanently shadowed craters near the moon's south pole, according to the first results from the Lunar Reconnaissance Orbiter (LRO) spacecraft announced today at a NASA press conference. Another instrument has returned hints of water ice in some of these cold spots, ... but it also showed signs of water ice in impossibly hot places, too.'"
This discussion has been archived. No new comments can be posted.

Shadowed Lunar Craters May Be Coldest Spot In the Solar System

Comments Filter:
  • by Anonymous Coward on Friday September 18, 2009 @08:55PM (#29473267)

    And here I thought it was my exwife.

  • Sterling Engine! (Score:1, Informative)

    by Anonymous Coward
    I RTFA and Pluto is 44 Kelvin. This is the average temperature, no doubt there is some crevasse on Pluto, but it hasn't been measured.
  • Really? (Score:4, Informative)

    by Useful Wheat ( 1488675 ) on Friday September 18, 2009 @09:00PM (#29473291)

    Since nobody is going to read it, the coldest temperature is 33K. The reason they care is because they'll probably find a lot of ice there.

    I'm not sure how I feel about this. I was of the understanding that space was on the order of 3K due to the cosmic background radiation. 33K is positively warm compared to this.

    • According to wikipedia even pluto is 43 degrees kelvin. the sun shines enough even out that far that pluto is 40 degrees warmer than the CBR.

      • According to wikipedia even pluto is 43 degrees kelvin. the sun shines enough even out that far that pluto is 40 degrees warmer than the CBR.

        In the winter when the atmosphere freezes I bet parts of pluto get colder than 33 kelvin.

    • Re: (Score:2, Informative)

      by G33kGuy ( 1152863 )
      Space isn't really cold as there isn't anything to be cold. As for tiny particles in space, their temperature would vary greatly depending on their distance from the sun (or other heat source).
      • Re: (Score:3, Funny)

        by dkleinsc ( 563838 )

        Are you saying Khan Noonien Singh was wrong when he told Kirk that "It is very cold in space"?

    • Re:Really? (Score:5, Interesting)

      by MartinSchou ( 1360093 ) on Friday September 18, 2009 @09:20PM (#29473401)

      Well, there could be some other reasons for wanting to know.

      If you build a moon base, you could use these spots for some interesting stuff. Like infra-red observatories, which I think need to have a cold sensor to increase sensitivity.

      Additionally 33 Kelvin is low enough that you can use at least one iron based superconductor [wikipedia.org] for energy storage. That way you can have huge arrays of solar panels or similar, and just dump surplus energy into a superconducting magnetic energy storage [wikipedia.org].

      The superconductors would also give you essentially free cooling for particle accelerators, but I've no idea how large those craters are, nor if that'd even be useful.

      • Re:Really? (Score:4, Interesting)

        by quercus.aeternam ( 1174283 ) on Friday September 18, 2009 @09:55PM (#29473539) Homepage

        A look at the energy storage option was very interesting - One side effect is the generation of an extremely large magnetic field:

        "The biggest concern with SMES, beyond possible accidents such as a break in the containment of liquid nitrogen, is the very large magnetic fields that would be created by a commercial installation, which would dwarf the magnetic field of the Earth."

        If this is the case, even a small installation could be extremely good from a health standpoint, especially in the context of colonization. Though they would still be without the protective effects of the atmosphere, they would probably be protected from a significant amount of radiation.

        • ...One side effect is the generation of an extremely large magnetic field:

          "The biggest concern with SMES, beyond possible accidents such as a break in the containment of liquid nitrogen, is the very large magnetic fields that would be created by a commercial installation, which would dwarf the magnetic field of the Earth."

          Would that enable the potential to 'install' an atmosphere there and keep it? [given a practical way to do so in the near future]
          If so, that would be way too cool! [pun not intended, implied, nor endorsed...YMMV]

          My understanding of the whole magnetic field around a planetary body/moon is that the MF is what enables the keeping/holding an atmosphere...using Mars as an example.

          I am open for corrections and education on this...it seems too simple, but...

          • Re: (Score:2, Informative)

            by perrin ( 891 )

            No, you need gravity to hold an atmosphere, much more than the Moon currently has. A strong magnetic field helps, but is not necessary, as in the case of Venus.

            • Re: (Score:3, Funny)

              by rts008 ( 812749 )

              Damn! You are correct!
              Gravity is a stone cold bitch, and I know this first-hand! *facepalm*
              Thanks for the prompt reply and reminder that I need to think stuff all the way through. :-)
              I should not have overlooked that, and now feel foolish for my short-sightedness.
              Thanks for the "get a grip on reality" slap to the face for the half-baked question.
              Really, no sarcasm intended- I can't believe I missed that basic principle!

              *starts writing on chalkboard:
              "rts008 is a premature ejaculating dumbass" one hundred ti

            • by DoninIN ( 115418 )
              The moon has enough gravity to retain a significant atmosphere, for a long long time, even a geologically significant amount of time. Millions of years by some calculations, look at google groups, check out rec.arts.science possibly you can show me I'm wrong, if so nifty. The moon does not have enough gravity to have captured, or to have retained whatever atmosphere it would have had after it's capture, or more likely creation after the impact that probably formed the moon and changed the earth into the pla
        • by khallow ( 566160 )
          The problem here is that this is a local not global effect. Any magnet capable of lifting iron nails dwarfs the magnetic field of the Earth at a small scale.
      • We use superconductors for energy storage on earth. The refrigeration is not the limiting factor nor is it the most expensive part of the whole design. I don't see why they'd be any more useful on the moon really.

    • Re: (Score:3, Informative)

      by rm999 ( 775449 )

      See http://www.wisegeek.com/what-is-the-temperature-in-space.htm [wisegeek.com]

      It says that space is ridiculously empty *on average*, so a molecule floating around in the middle of nowhere probably has virtually no energy (except the cosmic background radiation). This is why the average temperature of space is so low.

      On the other hand, a molecule in our solar system gets hit by all sorts of radiation if it had direct line of sight with the sun, heating it to >40 kelvin.

    • Re: (Score:3, Informative)

      The 3K temperature comes from the background radiation in `empty' space (mostly photons, but longer wavelengths than visible light). If you are close to a star like the sun, you clearly get a lot more radiating heat than that. Satelites, for example, have heat shields to protect them from getting too hot and melting. Similarly, the surface of the moon that is in direct sunlight gets quite warm, about 75 degrees Fahrenheit (about 125 degrees C, so above the boiling point of water, if it was at standard pr
      • Re: (Score:3, Interesting)

        by cratermoon ( 765155 )

        125 degrees C is indeed above the boiling point of water at 1 atm. However, 125C is NOT 75 degrees F. More like 257F.

        We should all be glad that 75F is not above the boiling point of water, otherwise our bodies would turn to puffs of steam.

        • Good point. I'm not from the USA, so I converted it with google from celsius, for the benefit of the Yankees ;-) Not sure how I managed to mess it up, obviously 75 fahrenheit is not that warm!
    • by oatworm ( 969674 )
      I was of the understanding that revenge is a dish best served cold... and it's very cold... ON THE MOON!
  • Personally, I would have guessed it would be farther away like a moon of Jupiter or Pluto. To have a very cold place so close to us is pretty cool(the cheese is burning me).

    But does this have any practical use? Can we use this place for experiments of any kind or is it just pure knowledge?

    • But does this have any practical use? Can we use this place for experiments of any kind or is it just pure knowledge?

      Radiotelescopes (IR mainly) would have a great spot there. I suppose.

    • > But does this have any practical use?

      Yes. Mining water.

    • by Potor ( 658520 )

      really. just read the article and then ask an intelligent question.

      fta:

      Shivering in at a mere 33 degrees above absolute zero, the regions are likely places to find deposits of water ice, a resource that would be in demand if astronauts ever live on the moon.

    • by mysidia ( 191772 )

      It's like a giant refrigerator... we could store things that need to stay cold to be preserved, instead of wasting energy to refrigerate them. Elimiante the ongoing cost of continued refrigeration

      We just gotta get them there. :)

  • Another instrument has returned hints of water ice in some of these cold spots, ... but it also showed signs of water ice in impossibly hot places, too.'" I wonder how much of that water is actually hydrated/hydrogen impregnated minerals and hydroxide compounds which probably are not lost as easily as water. Especially considering that their instruments detect the signature of hydrogen and the assumption is that it is chemically bound in water ice.

  • by Scorpinox ( 479613 ) on Friday September 18, 2009 @09:26PM (#29473425)

    The coldest spot in the universe would be in Boulder Colorado where they do absolute zero experiments.

    [source: http://www.smithsonianmag.com/science-nature/phenom-200801.html ]

    • Re: (Score:2, Funny)

      by Cheesetrap ( 1597399 )

      http://www.smithsonianmag.com/science-nature/phenom-200801.html

      The speed of light, as we've all heard, is a constant: 186,171 miles per second in a vacuum. But it is different in the real world, outside a vacuum; for instance, light not only bends but also slows ever so slightly when it passes through glass or water. Still, that's nothing compared with what happens when [Lene Vestergaard] Hau shines a laser beam of light into a Bose-Einstein condensate: it's like hurling a baseball into a pillow. "First, we got the speed down to that of a bicycle," Hau says. "Now it's at a crawl, and we can actually stop itâ"keep light bottled up entirely inside the BEC, look at it, play with it and then release it when we're ready."

      O.O

      Since my boggled eyes probably won't constitute a worthy post, I guess I should add this [xkcd.com]. :) (it's a tiny bit relevant lol)

    • by Criliric ( 879949 ) <Shane.belaire@gmail.com> on Friday September 18, 2009 @10:10PM (#29473597)
      no where on that page does it say that they have made it to absolute zero... infact:

      Physicists acknowledge they can never reach the coldest conceivable temperature, known as absolute zero and long ago calculated to be minus 459.67F.

      • Re: (Score:2, Informative)

        by Anonymous Coward

        That doesn't mean they can't do experiments related to absolute zero including attempts at approaching it.

        He didn't say they did experiments "at" absolute zero.

  • The coldest place in the solar system is obviously inside the heart of my ex-wife. And probably other Slashdotter exes!
  • by gmuslera ( 3436 ) on Friday September 18, 2009 @09:56PM (#29473541) Homepage Journal

    The moon is a frigid mistress

  • any ice there?

  • by argent ( 18001 ) <peter@slashdot . ... t a r o nga.com> on Friday September 18, 2009 @10:28PM (#29473669) Homepage Journal

    Back when we though Mercury was tidally locked to the Sun (instead of being tidally locked to the Sun and Venus) Larry Niven wrote a short story "The Coldest Place", in which the backside of Mercury, always facing away from the Sun, was the coldest place in the solar system.

    Good guess, Larry. Not quite right, but ... good going.

    • by AJWM ( 19027 ) *

      That was actually Niven's first sale, and the news that Mercury wasn't locked in a 1:1 resonance came out between acceptance and publication. They decided to go ahead with it anyway. It's still a good story, it just takes place in a slightly alternate universe.

      • by argent ( 18001 )

        It's still a good story, it just takes place in a slightly alternate universe.

        Since Vermont was supposed to have passed the first organ bank laws in 1993 (The Jigsaw Man) and the first Mars landing was in 1996 (Eye of an Octopus) I think that's a given.

        Pity, really. I was looking forward to learning what Hard and Soft Plith was.

        On the other hand, it's probably a good thing that we've gotten past the attitudes displayed in How the Heroes Die.

        • by AJWM ( 19027 ) *

          Pity, really. I was looking forward to learning what Hard and Soft Plith was.
          On the other hand, it's probably a good thing that we've gotten past the attitudes displayed in How the Heroes Die.

          Agreed. And on the gripping hand, it doesn't prove that the core of our galaxy hasn't already exploded (although the central black hole makes that unlikely).

    • OTH the lunar poles might be a good place to "wait it out".

  • by Tablizer ( 95088 ) on Friday September 18, 2009 @10:58PM (#29473789) Journal

    So, Minnesota got bumped to 2nd?

  • by BoldAndBusted ( 679561 ) on Friday September 18, 2009 @11:04PM (#29473821) Homepage

    So, THIS is where the data centers in 2150 will be.... Will Amazon be selling "Moon Computing" then? :)

  • What about craters in kuiper belt objects?

    I would have thought these to be colder due to the distance from the sun.

    • Yeah if they have a nice stable rotation perpendicular to the sun. The microwave background should be very slightly warmer in close to the sun because it gains energy falling down hill. OTH dust close in to the sun may slightly obscure the background, making shadowed places a bit cooler. Then the moon has a warmer core than a kuiper belt object, so maybe that is the biggest factor. Less heating from below.

  • by Tablizer ( 95088 ) on Saturday September 19, 2009 @12:45AM (#29474269) Journal

    But the sun don't shine in Uranus either

    • Re: (Score:3, Interesting)

      by petrus4 ( 213815 )

      Uranus needs to be renamed back to Herschel, after the guy who discovered it. Stupid jokes come up every time the planet is mentioned.

      • You can call Uranus whatever you want.
      • by Tablizer ( 95088 )

        Uranus needs to be renamed back to Herschel, after the guy who discovered it. Stupid jokes come up every time the planet is mentioned.

        Then you'd get "Herschy bars are coming out of Uranus", or "My Uranus Herschels really bad".
             

    • Lets leave my bathing habits out of this, shall we?

    • Uranus doesn't get sunlight, but I'm sure the turbulent gasses generate some heat.

      What? That was a serious statement!

  • I wonder how practical it would be to tap a thermal gradient for energy on the moon, considering the surface temperature ranges from -153 C to 107 C.

  • First, craters faced and pock marks, cellulite like cottage cheese, and to top it off FRIGID. A "honeymoon" indeed. "One small step for man.....
  • ...I thought the coldest places in the solar system were the moons of Neptune. You know, how like they're much further away from the Sun than our moon, and how they're highly reflective. They have volcanoes of liquid nitrogen on those moons for pete's sake.
    • Re: (Score:3, Informative)

      by AJWM ( 19027 ) *

      They have volcanoes of liquid nitrogen on those moons for pete's sake.

      But nitrogen freezes at 63 K, so that liquid nitrogen is at least twice as warm as the 33 K found on the Moon. Now, if those moons have craters at their poles that are permanently shielded from sunlight....

      (Actually there are other factors in play, like the thermal conductivity of whatever the moon in question is made of, heating effects of tidal friction, etc.)

  • Oort Cloud? (Score:3, Interesting)

    by bryan1945 ( 301828 ) on Saturday September 19, 2009 @06:18AM (#29475403) Journal

    Does the Oort cloud count as part of the solar system, or is it beyond the heliosphere? Either way, it's gotta be a tad chilly out there.

  • I understand the expense. I don't want all sorts of 'hub bub" about that.

    Wouldn't it be handy to be able to use some of these naturally occurring spots within our solar system for experiments? Granted getting to these locations is tough and expensive, but that could be overcome with focus.

    Then again societal focus has been missing from this country for about 30+ years.

  • I'm no astrophysicist, but I remember seeing a video a couple years back that said Pluto gets much less light than the moon gets from earthshine. Earthshine should be warming up those crevices two weeks out of every four. So, does anybody know why that wouldn't make the crevices warmer than Pluto?
    • The crater is a mormon, it does not consume earthshine.

      • by WH44 ( 1108629 )

        The crater is a mormon , it does not consume earthshine.

        Sorry, a "mormon"? Is that a typo? I've never seen a crater going door-to-door in a suit. ;-)

        • No it wasn't a typo. You may not know that Mormons abstain from drinking alcohol. "Earthshine" was a play on the word "moonshine". (home-made corn whiskey).
          • by WH44 ( 1108629 )
            Ah! Of course, how could I have missed it! I know about Moonshine: great granddaddy made his own. I also know a lot about Mormons (the LDS Church) - I just don't generally associate them with being teetotalers: they are many other things, too. Full disclosure: I'm a Baha'i, and hence also a teetotaler.
    • These craters are at Luna's South pole. Their interiors are shadowed both from the sun and from the Earth. Think about it. If Earthshine could reach them so could sunlight.

      • by WH44 ( 1108629 )

        These craters are at Luna's South pole. Their interiors are shadowed both from the sun and from the Earth. Think about it. If Earthshine could reach them so could sunlight.

        You're right. I should have done my homework.

        However, you are wrong about shaded by from the Sun necessarily implying shaded from Earth, depending on orbit, rotation and tilt, up to half of the moon could be continually shaded from the Sun without being shaded from Earth.

        • > However, you are wrong about shaded by from the Sun necessarily implying
          > shaded from Earth...

          Not for the general case: consider the Earth-Sun L1 point. For the Moon specifically.

          • by WH44 ( 1108629 )

            > However, you are wrong about shaded by from the Sun necessarily implying > shaded from Earth...

            Not for the general case: consider the Earth-Sun L1 point. For the Moon specifically.

            Sorry, you lost me as to what the Lagrange Points have to do with it.

            I was thinking, if the Moon were tidally locked to the Sun instead of Earth (I know, not possible), or had one pole always tilted toward the Sun.

            • > Sorry, you lost me as to what the Lagrange Points have to do with it.

              An object at Earth-Sun L1 tidally locked to the Earth would see Earthshine only.

              > I was thinking, if the Moon were tidally locked to the Sun instead of Earth
              > (I know, not possible), or had one pole always tilted toward the Sun.

              There are all sorts of theoretical possibilities.

              • by WH44 ( 1108629 )

                An object at Earth-Sun L1 tidally locked to the Earth would see Earthshine only.

                Ah! I totally overlooked that possibility. There are two problems with that: it is L2, not L1; L2 is (just) outside the Earth's umbra. The Wikipedia article on Lagrangian points (L2) [wikipedia.org].

                • No. I said and meant L1.

                  • by WH44 ( 1108629 )

                    Urm? If it were at L1, the same thing would happen that happens at a solar eclipse. The Moon gets light from both sides. Nearly the whole Moon is illuminated. Unless the rotational axis of the Moon is near perfectly in the plane perpendicular to the line between Earth and Sun at that point, even the poles will be illuminated.

                    Is that what you mean, or do you mean something else?

                    If it were at L1, then tidal locking with the Earth would be unlikely, and so a well aligned axis would also be unlikely.

                    • Why would tidal locking be unlikely at sun-earth L1? (mind you, L1 and L2 are not quite stable, so it would be unlikely that a large object would be there at all) But there is no reason that such an unlikely object could not be tidally locked with the earth. (and sun)

                      But I think what you were getting it is that an object that is residing in the L2 point, and is tidally locked with the earth would have a far side that never sees light from the earth or sun, and thus could be very cold.
                    • by WH44 ( 1108629 )

                      Why would tidal locking be unlikely at sun-earth L1? (mind you, L1 and L2 are not quite stable, so it would be unlikely that a large object would be there at all) But there is no reason that such an unlikely object could not be tidally locked with the earth. (and sun)

                      I was somehow thinking, that with the balancing of the Earth's and Sun's gravitational pulls, that tidal forces would cancel, which is on a moments reflection, wrong. Sorry.

                      But I think what you were getting it is that an object that is residing in the L2 point, and is tidally locked with the earth would have a far side that never sees light from the earth or sun, and thus could be very cold.

                      I was thinking that if L2 were inside the umbra (it isn't), then none of the Moon would ever see the Sun or Earthshine (it would always be facing the dark side of Earth). Regardless of rotation or axis orientation.

Two can Live as Cheaply as One for Half as Long. -- Howard Kandel

Working...