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Moon Space

Unbelievably Large Telescopes On the Moon? 292

Posted by CmdrTaco from the thats-no-moon dept.
Matt_dk writes "A team of internationally renowned astronomers and opticians may have found a way to make "unbelievably large" telescopes on the Moon. 'It's so simple,' says Ermanno F. Borra, physics professor at the Optics Laboratory of Laval University in Quebec, Canada. 'Isaac Newton knew that any liquid, if put into a shallow container and set spinning, naturally assumes a parabolic shape, the same shape needed by a telescope mirror to bring starlight to a focus. This could be the key to making a giant lunar observatory.'"
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Unbelievably Large Telescopes On the Moon? More

Unbelievably Large Telescopes On the Moon?

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  • Ob (Score:5, Funny)

    by Hognoxious ( 631665 ) on Thursday October 09, 2008 @07:50AM (#25312203) Homepage Journal
    Actually, it just seems large because the moon looks so small. My guess is you're holding the telescope the wrong way round.

    • Re: (Score:3, Informative)

      by Probie ( 1353495 )
      no one can hold the telescope....didn't you read? It's "unbelievably large"!

      • Re:Ob (Score:5, Funny)

        by ozphx ( 1061292 ) on Thursday October 09, 2008 @09:17AM (#25313343) Homepage

        I have a certain amount of... shall we say... practice.... in this area.

      • Re: (Score:2)

        by GweeDo ( 127172 )

        But at 1/6 earth gravity can I lift it?

        • Re: (Score:2, Interesting)

          by Probie ( 1353495 )
          if the strongest man on the planet can lift aprox. three times his own weight, then on the moon he should be able to lift 18 times his own (earth) weight.... so i guess the question is: does the telescope weigh less than that? And are you the strongest man on the planet?

  • No Way!!! (Score:2, Funny)

    by naz404 ( 1282810 )
    I can't believe it! Do you? *gasps*

    • I can't believe it! Do you? *gasps*

      By definition, no one can. If I could believe it, it wouldn't be "unbelievably big."

  • I'm Being Followed By A... (Score:4, Funny)

    by Illbay ( 700081 ) on Thursday October 09, 2008 @07:52AM (#25312225) Journal
    ...n unbelievably large telescope on the moon.

  • Wow (Score:2, Interesting)

    by ekimd ( 968058 )
    As with many ideas, this is so simple I can't believe we haven't thought of this before.

  • Summary is completely misleading... (Score:5, Insightful)

    by argent ( 18001 ) <peter&slashdot,2006,taronga,com> on Thursday October 09, 2008 @07:59AM (#25312289) Homepage Journal

    When I saw the summary I actually HOPED it would be misleading, because it makes it sound like nobody had thought of liquid mirror telescopes before. Now it's possible that they were just copying a similarly misleading article, but no... even has a nice photo of the Large Zenith Telescope to spice things up. Space Fellowship 1 - Slashdot 0.

  • "It's so simple," (Score:3, Funny)

    by CubicleView ( 910143 ) on Thursday October 09, 2008 @08:00AM (#25312297) Journal
    Yeah, building stuff on the moon is a doddle.

  • New? (Score:4, Informative)

    by Kythe ( 4779 ) on Thursday October 09, 2008 @08:00AM (#25312311)

    Hmmm...as the article notes, the idea of liquid mirror telescopes isn't new, so it seems a tad odd that this is being trumpeted as a breakthrough.

    The ionic liquid coated with silver is cool, though.

    • Re: (Score:3, Insightful)

      by Thelasko ( 1196535 )
      I think the break through is the part where they build it on the moon. I understand how building a massive telescope on the moon will be difficult, and although this may be slightly easier, I don't consider it a massive breakthrough.

      I would consider a massive breakthrough building the telescope out of moon dust, or some other material readily available on the moon. That way, we don't have to transport massive amounts of equipment to the dark side of the moon.

      • Not Dark Side (Score:5, Insightful)

        by camperdave ( 969942 ) on Thursday October 09, 2008 @08:31AM (#25312677) Journal
        we don't have to transport massive amounts of equipment to the dark side of the moon.

        It's FAR SIDE people! Far Side, Far Side, Far Side. Like the cartoon. The Moon is tidally locked to Earth, so there's a Near side and a Far Side. If it were tidally locked to the Sun, then you'd have a light side and a dark side. But it's not, so we don't. There is no dark side of the moon, except for the ever changing half that's facing away from the sun at the moment.

        • Re:Not Dark Side (Score:4, Funny)

          by Anonymous Coward on Thursday October 09, 2008 @08:38AM (#25312775)

          Oblig. "There is no dark side of the moon. It's all dark."

        • Re:Not Dark Side (Score:5, Insightful)

          by MBGMorden ( 803437 ) on Thursday October 09, 2008 @08:42AM (#25312827)

          While I generally wouldn't use the term "dark side" myself, you do realize that a lot of terms are just terms because that's what they've traditionally been called right? Just as not everyone who says "Ooh, a falling star!" really believes that it's LITERALLY a falling star, I'd hazard a guess that a lot of people who perfectly well understand that the other side of the moon isn't actually dark, would still call it the "dark side" because it's been called that for so long.

        • Re:Not Dark Side (Score:5, Insightful)

          by wooferhound ( 546132 ) <.moc.dnuohrefoow. .ta. .mit.> on Thursday October 09, 2008 @09:02AM (#25313117) Homepage
          There is a Dark Side . . .
          but it's at the top, and inside of a crater as suggested in TFA

        • Re: (Score:2, Informative)

          by fmstasi ( 659633 )
          It may be interesting to know that in Italian it's the "hidden face" of the moon (la faccia nascosta della luna) - personally I have always been confused by the English terminology.

          I'd love to know the terminology used by other languages...

        • Re:Not Dark Side (Score:5, Funny)

          by Chris Burke ( 6130 ) on Thursday October 09, 2008 @09:40AM (#25313785) Homepage

          It's FAR SIDE people! Far Side, Far Side, Far Side. Like the cartoon.

          So... you're saying it's populated by bipedal cows and mad scientists?

        • Re: (Score:2)

          by trongey ( 21550 )

          ...is tidally locked to Earth, so there's a Near side and a Far Side...

          So what do you call that side when you're in a spaceship that's orbiting the Moon? What if you're living in a telescope lab on that side? It would be kind of dumb to call the side you're on the far side now wouldn't it?

    • To be fair, TFA doesn't "trumpet this as a breakthrough". It's the ionic liquid coated with silver which is new and the breakthrough that would make lunar liquid telescopes feasible.

  • It WILL happen one day (Score:4, Interesting)

    by $RANDOMLUSER ( 804576 ) on Thursday October 09, 2008 @08:01AM (#25312319)
    Since the "dark" side of the moon is protected from the radio emissions from Earth, I think it's inevitable that the dark side will one day be "the" spot for big radio telescope arrays. Why not put our biggest optical telescope there as well?

    • Re: (Score:3, Funny)

      by Anonymous Coward

      there is no dark side of the Moon really... as a matter of fact it's all dark

      • Re:It WILL happen one day (Score:5, Informative)

        by Speare ( 84249 ) on Thursday October 09, 2008 @08:28AM (#25312643) Homepage Journal

        The so-called "dark side of the moon" does not refer to the lack of sunlight or nighttime conditions. All parts of the moon go through the same kind of night/day cycle that the Earth does, only 29.53x slower.

        The phrase refers to radio darkness. The moon spins at the same rate it orbits the Earth, so the same familiar craters are always facing us. Anyone standing amongst those craters is being bombarded by the radio noise chatter of the whole Earth population. Anyone standing on the opposite side of the moon can pick up none of that.

        One potential problem with setting up bases on the dark side is how to communicate with them. To maintain the radio silence, you can't just stick a radio-based communication moon-satellite out there. It would be very expensive to maintain a cable or laser hookup for any significant distance along the moon surface. So you're left with small windows of time you can communicate, or you work on a focused laser-based comm link with a moon-satellite. That reminds me... what's the "geosynchronous" radius for moon-satellites?

        • Re:It WILL happen one day (Score:5, Interesting)

          by interiot ( 50685 ) on Thursday October 09, 2008 @08:39AM (#25312797) Homepage
          Stick at relay satellite at the Earth-Moon L4 or L5 [wikipedia.org]. That means the telescope couldn't be exactly opposite Earth, but if there's still a lot of room where it's shielded from Earth but still in view of L4 or L5.

        • Re:It WILL happen one day (Score:5, Informative)

          by CXI ( 46706 ) on Thursday October 09, 2008 @08:41AM (#25312813) Homepage
          Dude, the grandparent was making a reference to a Pink Floyd album. *sigh* Kids these days... http://en.wikipedia.org/wiki/The_Dark_Side_of_the_Moon [wikipedia.org]

        • Re: (Score:3, Interesting)

          by Anonymous Coward

          Don't be ridiculous; the moon is both smaller, less geologically active and less populated that any place on earth.

          It would be a simple thing to install a fiberoptic "lunar telegraph" from one side to the other,.

          It's not like you have to dig under peoples houses and get easements, after all :)

          • Re: (Score:2, Funny)

            by Anonymous Coward

            Don't be ridiculous; the moon is both smaller, less geologically active and less populated that any place on earth.

            Not so, my house is smaller, less geologically active, and more populated than the moon.

          • Re: (Score:2)

            by Speare ( 84249 )
            Travel across the surface is expensive and cumbersome and dangerous. Multiple landings here and there is expensive and cumbersome and dangerous. The moon is not geologically active on its own, but in case you hadn't noticed, rocks hit the moon all the time. You'd have to harden ALL that cable length against hard solar radiation and also significant meteorite damage, or you'll be out there every week fixing some crack that's developed.

            • Re: (Score:2)

              by T-Ranger ( 10520 )
              It was dangerous in the '60s because you had zero chance of rescue if you get in trouble. If humanity is going to be building telescopes on the moon, that means moon bases. And moon tow trucks. Or at least other rovers around.

              Fiberoptics would be unaffected by solar radiation.

              Getting the cable even 6" under the surface would be pretty protective of most threats, I think.

              The alternate would be what.. A radio relay satellite? What are the relative odds of something hitting a satellite and a cable 5cm wide x 5

        • Re: (Score:3, Interesting)

          by ari_j ( 90255 )
          Would that by cynthiosynchronous? I'm not sure, although I know that pericynthion is to the moon as perigee is to the Earth. At any rate, I suspect that the month-long rotational period of the moon means that a synchronous orbit would be outside of the moon's influence to the point it would be picked off by the Earth. In fact, rough figuring with my calculator shows that the radius of a moon-synchronous orbit is 230 times the distance of the moon from the Earth. You'll have to just play around with Lagr

          • Re: (Score:2)

            by Speare ( 84249 )
            Thanks, that's why I put "geosynchronous" at orbit-- we know what it means but it's not the right word exactly. I also thought that such an orbit might be unworkable due to the low rotational speed, but appreciate the math you gave. I don't think we've injected anything into body-synchronous orbits for any body other than Earth, have we? I can't be bothered to figure out the portion of "dark side" real estate is inside or outside the line of sight of L4 and L5.
        • Er... by "geosynchronous", do you mean lunasynchronous, i.e. remaining over one spot on the moon? There isn't one -- the moon's rotational period is so slow that at the distance required, the earth's gravity has more effect than the moon's. You'd need a set of lower orbiting satellites.

    • Since the "dark" side of the moon is protected from the radio emissions from Earth, I think it's inevitable that the dark side will one day be "the" spot for big radio telescope arrays. Why not put our biggest optical telescope there as well?

      Because for close to half the time the far side of the moon is completely blinded because it is looking towards the sun.

    • Re: (Score:3, Insightful)

      by sp332 ( 781207 )

      Um, how will it transmit images back to earth, with the entire moon blocking radio transmissions?

      • Re: (Score:2)

        by evanbd ( 210358 )
        Burst transmissions to a satellite while not observing? Optical focused beam links to a relay satellite also work. As another commenter pointed out, the L4 / L5 points are the obvious spots. Longer term, you could consider laying optical fiber.
  • Too big to fit into our current spaceships is nowhere near unbelievable.

    The range of unbelievable scale starts at 1000m. This idea could work for a rotating mirror that large, but not on the moon unless you're willing to lay rather a lot of maglev track to support the weight of the outer edges of the mirror, or to take a ludicrous amount of support structure to the moon.
  • That's great. When they want to look at a different patch of sky, they can just just swivel the moon.

  • Read TFA, sounds fundamentally flawed. (Score:4, Interesting)

    by plasmacutter ( 901737 ) on Thursday October 09, 2008 @08:20AM (#25312539)

    The "liquids" to be used are less dense than water, and being placed on the lunar surface, which is covered in dust several times finer than baking powder.

    I'd give it about 3-5 days (depending on the size) before the "revolving liquid mirrors" become revolving lunar mud pies.

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      couldn't possibly be a lid on it to protect it from lunar dust/solar winds/micrometeorites. No possible way they'd think of that. Absolutely implausible that they'd use a static charge to repel ionized particles either, just fucking inconceivable.

    • Re:Read TFA, sounds fundamentally flawed. (Score:5, Insightful)

      by mlush ( 620447 ) on Thursday October 09, 2008 @08:30AM (#25312659)

      The "liquids" to be used are less dense than water, and being placed on the lunar surface, which is covered in dust several times finer than baking powder.

      I'd give it about 3-5 days (depending on the size) before the "revolving liquid mirrors" become revolving lunar mud pies.

      How? Is the wind is going to blow the dust onto the mirror??

      • Re: (Score:3, Informative)

        by budgenator ( 254554 )

        The solar wind. It "blows" which actually causes a static charge to build up twice a month as the Moon move into and out of the Earth's magnetosphere. This causes the dust to levitate because of electrostatic repulsion.

  • Ha (Score:5, Funny)

    by Daimanta ( 1140543 ) on Thursday October 09, 2008 @08:21AM (#25312547) Journal

    This is total lunacy!

  • Spin it & freeze it (Score:5, Interesting)

    by Alain Williams ( 2972 ) <addw@phcomp.co.uk> on Thursday October 09, 2008 @08:26AM (#25312615) Homepage
    If they spin it up, let is settle and then freeze it they would have a perfect steerable mirror. Any reason why this would not work, perhaps the crystals that form on freezing making imperfections ?

    It would mean having to choose the right material (solid at moon temperature, liquid at not too much more, small/no surface crystals on freezing, ionic so that it can be coated with silver, ...). Making something like this on the moon would be much cheaper than taking it up there.

    OK: I understand that they might not want to steer if far off vertical to keep things cheap but I would have thought that a little directionality would be a boon.

    • Re:Spin it & freeze it (Score:4, Insightful)

      by actionbastard ( 1206160 ) on Thursday October 09, 2008 @09:07AM (#25313183)
      In order for the 'mirror' to maintain its shape it would have to be continuously spinning during the 'freezing' phase. If it were to stop and 'settle' you would end up with a useless, slightly convex, mirror. Also, whether you find the materials necessary to manufacture the mirror on the Moon or not, the machinery to produce the mirror and the rest of the observatory need to be sent from Earth, first, which makes this a totally unfeasible, insanely expensive. proposal.
      Smart science type guys do it again. "Hey, we can make 'X' for really cheap on the Moon. The only problem is that we have to get to the Moon to make it really cheap."

      • the machinery to produce the mirror and the rest of the observatory need to be sent from Earth, first, which makes this a totally unfeasible, insanely expensive.

        But under the proposal they would have to do that anyway - to create a spinning liquid mirror; the only extra cost would be the heating equipment and whatever to steer the telescope a bit. I agree that making it highly steerable might need costly kit, but to just tilt it 10 or 20 degrees might be cheaper.

    • Well, people use liquid telecopes here on Earth because they are perfectly parabolic. Solidifying it will probably change that.

    • its the moon after all, cheaply and bountifully available

  • If this would have been a "steampunk" telescope on the moon, then this article would have made boingboing.

  • That's no moon (Score:3, Funny)

    by j00r0m4nc3r ( 959816 ) on Thursday October 09, 2008 @08:36AM (#25312741)
    This could be the key to making a giant lunar observatory

    Or a fully functional battle-station.

  • It just looks big because you're seeing it through a powerful telescope.

  • It'll never fly. (Score:5, Funny)

    by DeeVeeAnt ( 1002953 ) on Thursday October 09, 2008 @08:44AM (#25312855)
    Look, I don't care who you work for sonny, you are not flying with more than 100ml of liquid in your luggage, so hand it over. Bloody astronauts think they are so superior.

  • talked about making silvered-ice mirrors on the Moon in his 1981 story The Patchwork Girl [fantasticfiction.co.uk]. Not quite liquid, but it would certainly start out that way, and probably at least grossly shaped in the same method. (Figuring and finish would probably be done the traditional way, though.)

    And being solid, an ice mirror would be STEERABLE.

  • Put the telescope 550 AU out (Score:5, Interesting)

    by Anonymous Coward on Thursday October 09, 2008 @08:55AM (#25313015)

    ...at the sun's gravitational focus. You'd be able to resolve a planet halfway across the galaxy.

    First link I pulled from Google (but there are several others): http://www.centauri-dreams.org/?p=176 [centauri-dreams.org]

    • Ten times the Earth-Pluto distance? You'd better be banking on a long MTBF for that. And the time required to change the telescope's orientation would make Hubble look nippy. ;) You'd really want a vast constellation of telescopes out at that range, distributed for redundancy. Combining the various telescopes' signals could give you a mighty resolution, as a bonus. A proposal for a civisation making a Dyson sphere, perhaps.

  • Oblig. Futurama Reference (Score:3, Funny)

    by ari_j ( 90255 ) on Thursday October 09, 2008 @09:05AM (#25313151)
    Everyone, sing with me:

    We're whalers on the moon
    We carry a harpoon
    But there ain't no whales
    So we tell tall tales
    And sing a whaling tune

  • How in the world will they protect the device from micro & macro impacts?

  • would seem to be a problem. I mean, if you get a few strikes of dust particles whacking your liquid mirror every couple of hours, won't it always have a bad picture?

    • Doesn't happen that often.

  • Don't make big plans, 'cause you're broke... (Score:5, Informative)

    by Simonetta ( 207550 ) on Thursday October 09, 2008 @09:39AM (#25313757)

    Don't make big plans, 'cause you're broke...

    You can't have a trillion dollar bailout of the rich bankers, buy up every dishwasher's quarter-million dollar underwater mortgage, hold a permanent-endless war on the other side of the world, ... and have a giant telescope on the moon. It's not possible, it's science fiction.

        All the space exploration projects being talked about and planned for the 2020's may actually happen...in the 2120's or 2220's. Not in ten years from now.

        I know that you're all young and starry-eyed, but in the bankrupt USA, reality rules. And reality says that there isn't going to any giant new space program in the 2010's-2020's.

        Don't just mod me to -1 for simply telling you the truth. And don't tell me how small the giant new space program is compared to other absurd federal government programs. Those programs are toast also.

        My American friends...you are simply broke... you have dreams... but you have no money.

    • Re: (Score:2, Funny)

      by JordanH ( 75307 )
      We're not just broke, our debt is unbelievably large!
    • I'm not sure where you're getting "space exploration projects being talked about and planned for the 2020s". There is literally no timetable for a "return to the moon", let alone permanent occupation, let alone Big Science like a lunar telescope. The closest thing I can get to your "2010-2020s" estimate is that there's going to be a review of lunar habitation concepts around about 2011.

  • Exactly how would this work when Hubble's main mirror was 2.3 microns off, which in turn caused the Hubble to become useless until the mirror was replaced? Can you actually spin a liquid so precisely that you get a product that is worth the expense?

    • > Exactly how would this work when Hubble's main mirror was 2.3 microns off, which in turn
      > caused the Hubble to become useless until the mirror was replaced?

      They replaced the correcting plate, not the mirror.

      > Can you actually spin a liquid so precisely that you get a product that is worth the expense?

      It's been done.

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