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NASA Moon Space Science

Radio Telescopes on Moon to Study Cosmic Dark Ages 118

Posted by Soulskill
from the ye-olde-moone dept.
The Narrative Fallacy brings news that NASA has awarded a $500,000 grant to develop plans for an array of radio telescopes to be located on the moon. The telescopes would be used to gather data from the earliest stars and galaxies, observations of which are difficult from Earth due to the ionosphere and terrestrial broadcasts. The grant was part of NASA's sponsoring of 19 "Next Generation Astronomy Missions." Quoting: "The Lunar Array for Radio Cosmology (LARC) project ... is planned as a huge array of hundreds of telescope modules designed to pick up very-low-frequency radio emissions. The array will cover an area of up to two square kilometers; the modules would be moved into place on the lunar surface by automated vehicles. The new lunar telescopes would add greatly to the capabilities of a low-frequency radio telescope array now under construction in Western Australia, one of the most radio-quiet areas on Earth."
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Radio Telescopes on Moon to Study Cosmic Dark Ages

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  • Hrm. (Score:4, Funny)

    by KublaiKhan (522918) on Thursday February 21, 2008 @06:13PM (#22509190) Homepage Journal
    Just a bit far to go on a LARC, ain't it?

    < /british >
  • Outstanding (Score:5, Interesting)

    by Protonk (599901) on Thursday February 21, 2008 @06:14PM (#22509196) Homepage
    The moon makes for an excellent platform for automated telescopes. People are going to bring up the tired "appolo for diamonds" argument but it doesn't have any bearing on this. The moon has no atmosphere to speak of, little radio interference from the earth and ample room to set up a large array.

    This requires less investment than manned missions (which dictate a return and have a HUGE space/safety cost). It will allow us to see other things than what is suggested in the grant--Changra, hubble and the like all have been used for things that were not conceived of during the design phase.

    • by CRCulver (715279)
      Once we start putting radio telescopes, human colonies, and massive solar arrays up there, that little rock is going to be covered pretty fast.
      • by Protonk (599901)
        Not really. 3.793 × 10^7 sq. km is a lot of space. And if it is covered, so what? All the better.
      • by fred fleenblat (463628) on Thursday February 21, 2008 @06:37PM (#22509426) Homepage
        (a) the cost of transit to/from the moon per pound is so high that only the lightest, skinniest people like paris hilton will be allowed in space. in fact they should be required to be sent into space.

        (b) the moon has no oceans, therefore 100% of land area is available for condominiums, hotels, highrises, and shopping districts. Unlike the earth which of which only 20% or so is habitable land. Ideally we would launch the most habitable parts, like Washington DC, to the moon in their entirety to take full advantage of the economy of scale, then convert what was underneath Washington DC into higher value land, like a swamp.

        (c) as you could see from last wednesdays lunar eclipse, the educational value of viewing the lunar eclipse from the moon would have been greater than viewing it from earth. No child left behind and all that.

        What was the question?
    • Re:Outstanding (Score:4, Informative)

      by fred fleenblat (463628) on Thursday February 21, 2008 @06:19PM (#22509254) Homepage
      >> little radio interference from the earth

      Further, I suspect if you set it up on the far side of the moon, you'll get zero interference from earth at all. Maybe some 60 hz hum...but kilohertz and above should be clean.
      • by Protonk (599901)
        right. It is just easier to say "very little" than it is to say "none" and have to explain that I mean "practically none".
      • by sholden (12227)
        But that's where the alien moon base is...
        • Re: (Score:1, Funny)

          by Anonymous Coward
          if we land on the moon, aren't we the aliens?
          • Under the terms of the Galactic Confederacy, all these worlds are ours except Europa. Attempt no landing there.
        • Re: (Score:3, Funny)

          by gardyloo (512791)
          Not true! The only thing there is a "sound"stage where the aliens faked their Earth landing.
        • You may only be joking, but Buzz Aldrin, an astronaut on the Apollo [first moon landing] mission has clearly stated in an interview that they were approached and observed by at least one Unidentified Flying Object on their historical moon mission, while on the way to the moon.... Here's the interview on YouTube [youtube.com]
      • by mikael (484)
        Only yesterday, they were proposing to send some telecommunications satellites to orbit the Moon so that there would be all-over lunar coverage for astronauts with satellite phones.
      • by cnettel (836611)
        I wonder what the low-frequency observators will make of the fact that the emissions from a body orbiting Sol has remarkable signals in the 50-60 Hz range, and that the linear components of the two distinctive signals changes distinctively with a 24-hour period. (or: not all countries use 60 Hz, you insensitive clod! Try growing up with 50 Hz PAL CRTs and you would also be touchy about it!)
    • Re: (Score:3, Interesting)

      by Dr. Eggman (932300)
      Alright, but what happens when something breaks down? With no atmosphere to burn them up, smaller space debris may impact the surface near the telescope (and stirring up the soil) or the device itself. We already have hear of that the extremly abrasive qualities of the lunar soil. That soil that will find its way into the telescope (especially bad for any moving parts.)

      I too, however, am optimistic. Not so much about what the telescope will grant us, but rather the challenges to material science. Solution
      • We already have hear of that the extremly abrasive qualities of the lunar soil. That soil that will find its way into the telescope (especially bad for any moving parts.)

        Too bad we don't know how to design and build phased-array radars... oh, wait.
      • Re:Outstanding (Score:5, Interesting)

        by CodeBuster (516420) on Thursday February 21, 2008 @07:22PM (#22509800)

        We already have hear of that the extremly abrasive qualities of the lunar soil. That soil that will find its way into the telescope (especially bad for any moving parts.)
        I was going to mention the exact problem and it does has the potential to be a problem because, as you mention, lunar dust is extremely abbrasive and fine (imagine sub micron rock particulate with razor sharp and hooked edges because it has never been eroded by wind or water) so it tends to damage or compromise any softer materials that it comes into contact with. However, upon further reflection I believe that the problem, in this case, would be manageable for the following reasons:

        (a) The telescopes and related equipment, or at least the parts directly in conctact with the lunar surface, will not be moving around after touchdown so the amount of dust that gets disturbed should be minimal and landing air bags (ala the mars missions) should help shield any sensitive parts during the landing cycle. the parts that do move will not disturb the dust because they will not be in direct contact with the lunar surface AND there are no air currents or other atmospheric effects on the moon to whip up dust from parts moving around (even if they are only millimeters above average surface elevation) which are not in direct contact with the lunar surface.

        (b) radio telescopes can be made out of metals and durable plastics without the need for sensitive optics such as finely ground glass lenses so the danger from abbrasive lunar dust could be minimized in this regard by judicious use of durable and hardened parts.

        The micrometeorites are a more serious issue. There have been subsequent pictures taken by probes of known Apollo landing sites which reveal new small craters (i.e. craters which occurred near the landing sites in between the time when the probes took the pictures and when the Apollo astronauts left the moon on the ascent stages of their landing vehicles). It is possible that many smaller meteorites have struck the Apollo lander descent stages that were left behind on the moon (although nobody can be sure because they are too small to resolve individually on the lunar surface by telescope and nobody has gone back since to check on their condition). However, even with this potential problem the radio telescope offers an interesting solution.

        The individual telescope elements of the radio telescope are less important than the network of them which makes up the whole. This why radio telescopes on earth, such as the very long baseline array [wikipedia.org], with stations on different continents aggregated together into a single "picture", are distributed rather then building one VERY large singular dish (i.e. one half the size of earth). The individual telescope elements on the moon could be replaced with new ones as needed if individual units, for whatever reason, become non-operable.
      • by ceoyoyo (59147)
        Radio telescopes aren't like optical ones - they're mostly wire mesh, or tinfoilish stuff. A few holes in it aren't critical. The sensitive electronic bits don't make up much of the surface area.

        The parts of the telescope that will move are unlikely to be either large or anywhere near the surface. If there are any moving parts at all.
  • Yeah right (Score:2, Offtopic)

    by antifoidulus (807088)
    everyone knows they are just going to use the telescope to watch the Amazon women change clothes.
    • by geekoid (135745)
      And there's a problem with that?

      I wonder, what did you find buggy about the OS-X server?
      Just curious, I never used it myself.
    • by phrostie (121428)
      that must have been what that one they shot down was for
  • "The Lunar Array for Radio Cosmology (LARC) project
    The "lark" project? Oh, please. You're making this too easy.
  • this telescope can't be pointed anywhere near earth without the same disruptions. So we have a whole part of the universe unexplored.

    Here's an idea. For one hour there will be a total blackout on earth. Thats not to much to ask for the advancement of science. And think of the population explosion. I need somebody to pay for my SS. It could be done as part of a new holdiday called Festivus.
    • Re: (Score:3, Informative)

      by usul294 (1163169)
      The moon goes around the Earth, one face always faces the Earth. Over the course of 28 days the dark side of the moon will see the entire sky with a giant ball of rock in between the observatory and Earth
      • by rijrunner (263757) on Thursday February 21, 2008 @07:27PM (#22509856)
        Well, not quite.

        This type of observatory requires a lot of smaller units that add up to a total resolution of the receiving surface. The best resolution is directly overhead of the site. As you try to observe items that are low on the horizon, you lose a great deal of the quality of the observation as the effective size of the array is diminished.

        For example:

                                **** (what you are observing)

                                ^^^^ (The array).

        The array is effectively as wide as its deployment diameter.

        Now, suppose you are observing from a couple other angles:

                                          ****

                                ^^^^

        From that angle, the array is apparently smaller. You can angle them to make sure you have the same strength, but you have to increase the size of the array as a direct function of the observation angle to give equivalent baselines for the observation.

        So, yes, you can see in any direction around the Moon, but placement on the Moon is not a simple matter.

        Consider that you don't want it pointing towards the sun either. Or, maybe you do. That's an interesting argument right there. You'll get data from the sun, but you'll also have periods where you have nothing *but* data from the sun. Similarly, Jupiter kicks out a lot of radio signals. A lot of design decisions end up still needing a fairly complex shield to make sure that you're getting only the radio waves you are searching for.

        Arguably, you would want to place it near the lunar poles. Not for any of the BS arguments about the potential for water there, but because they have the least interference from Earth and the Sun. It also means you can survey the same stretch of sky for longer periods as out-of-plane bodies there are a lot easier to track and remain in the same cone of observation irrespective of the current lunar position. (ie, something that is at zenith over the lunar pole is not going to vary more than about 6 degrees from being overhead over the course of a year. Even something 25 degrees, or so, would still be visible pretty much all the time). If you go to lower latitudes, then it gets closer to a 14-day non-observation lineup followed by a 14 day period of variable observation from minimal to optimal and back as the object traverses the sky. The closer you get to the lunar equator, the more of the sky you will see, but the less the observation time and the more variable the quality of the observation.

        Ideally, they design a small inexpensive setup which can be done a few times on various areas of the Moon. Just choosing one set of criteria is going to be interesting. This is not like Hubble which can be pointed in any direction. There are a lot of rocks in the way.
        • How do you get data to/from the Earth? You'll need a satellite or repeaters or something. But if you stick it at the pole, maybe you can peek back over :)
          • How do you get data to/from the Earth? You'll need a satellite or repeaters or something. But if you stick it at the pole, maybe you can peek back over :)

            My intuition suggests that it would be cheaper to use relay satellites than to locate the observatory at the pole, if returning data was the only issue that affected where the observatory was placed (IIRC there's a slight delta-v advantage in landing near the lunar equator). However, other people have already pointed out some other good reasons why a lunar pole would be a good place to put it.

          • Re: (Score:3, Interesting)

            by rijrunner (263757)
            The observatory does not have to be directly opposite the Earth. Just behind the edge would work. You could then run a fibre-optic cable to a location nearby that is visible to Earth.
          • by khallow (566160)
            Halo orbit around the L2 point of the Earth-Moon system. In somewhat more understandable English, you can put a relay in orbit around one of the five equilibrium points where the forces of Earth's and the Moon's gravity keep an object in a fixed position with respect to the two bodies. The L2 point is on the far side of the Moon where the combined gravity of the Earth and Moon counters the centripetal forces of an object placed there. Technically the orbits there are unstable, but a relay with sufficient ma
  • Telescope[] MoonTelescopeArray;
    • Re: (Score:1, Offtopic)

      by clem (5683)
      Just be sure you use the delete[] operator when you're done using the telescopes.
      • I find it sad to see not only one, but two programming jokes modded offtopic. If you find them to be not funny, ignore it. And if you don't understand it, again ignoring is a much better policy than downmodding.
        • by tgd (2822)
          I think its because the moderators recognized the flaw in his suggestion to call delete() -- clearly the grandparent did not take into account the substantial object creation overhead, or he would've made a point of ensuring the telescopes were pooled and left for later generations.
  • by Grandiloquence (1180099) on Thursday February 21, 2008 @07:06PM (#22509680)
    Like most of NASA's programs, this basically amounts to a jobs program for scientists/engineers. Notice that the funding is for the plans for an array of telescopes, not for the actual construction of said array. Building an array of telescopes on the Moon would likely require astronauts to spend months on the Moon, even if most of the telescopes came pre-assembled. Without any infrastructure on the Moon to support those astronauts, building an array of telescopes there is a pipe dream, and will remain so for the foreseeable future.

    If any plans end up being actually produced, they'll likely be filed away in a drawer and forgotten. Pessimistic? Sure. But, that's the way NASA has worked for decades now.
    • At this point in time we don't even have a Manned Moon Mission in the planning horizon. It's Mars first right now. Of course the same launch vehicle can be used for both but we don't have a Lunar Lander (revive the old one and modernize?) nor do we have a way for astronauts to stay on the moon more than a week or so. Neither one of those is insurmountable but they are essential precursors to building a large structure manned or unmanned on the Moon.
    • by Abcd1234 (188840)
      Building an array of telescopes on the Moon would likely require astronauts to spend months on the Moon

      Good lord, did you even read the summary? Here, I'll quote the relevant bit for you:

      "the modules would be moved into place on the lunar surface by automated vehicles"

      See? No humans involved. You just land 'em on the lunar surface, and robotic vehicles are used to deploy them.

      Of course, that's not to say this isn't still a pipe dream. I'm willing to bet nothing will really come of it. But it's not a co
  • by QuantumG (50515) <qg@biodome.org> on Thursday February 21, 2008 @07:06PM (#22509684) Homepage Journal
    Why not just put the telescopes in a geostationary orbit around the Moon so they are always on the dark side and therefore shielded from the Earth? Soft landing telescopes of any significant size is hard work. The only reason lunar telescopes makes more sense than space telescopes in lunar orbit is if you build the lunar telescopes from lunar materials... and we're not anywhere near that capability yet.

    • by phrostie (121428)
      interesting. you'd get a cleaner signal but there would be other obsticals.

      wouldn't you need some form of communications system im place to route the signals?

      possible a satellite in a lunar polar orbit?
    • by Fëanáro (130986) on Thursday February 21, 2008 @07:29PM (#22509892)
      There are no geostationary orbits that stay behind the moon. But we could maybe put a satellite in a Lissajous orbit around the lagrange point [wikipedia.org] L2 behind the moon.

      To send signals back you would need a relay satelite thougth
      • by kryten_nl (863119)
        What a great idea and so original too. I'll help by thinking of a snazy name for the satellite .... got it. How about James Webb Space Telescope [wikipedia.org]?
      • by Steneub (1070216) on Thursday February 21, 2008 @08:20PM (#22510316)
        Logged in to post exactly this. Putting a telescope in a lagrange point solves the problem of not being able to directly communicate with it due to it being on the other side of the moon. Another advantage of direct communication is getting visual confirmation of any movements or adjustments made. Sensors are great, but I don't care how good the tech is - something will always go wrong that you didn't think of.
      • A halo orbit about the Lagrange 2 point in the Earth-Moon system would be sufficient. From Earth it would appear as a ring behind the moon. Keep in mind that the L2 point is in unstable equilibrium. That type of orbit would require about 100 m/s delta V maintenance per year. I have not read the proposal but perhaps a trade study showed a significant mass savings over the long term by landing your equipment. Maintaining an array of satellites might *actually* be more expensive
    • by rijrunner (263757)
      Because there is no stable geo-synchronous orbits around the Moon?

      Also, for the wavelengths they are looking at, you need something that is kilometers wide and able to be effectively controlled.

      They are not talking about some telescope with a mirror and camera. This is closer to a huge array of dish antennas that are linked together and point in a given direction. They actual dish can be fairly small and moved about to change the size of the baseline.

      • Actually, they appear to be talking about LOW frequency Radio astronomy. That is, from 1Hz to probably 30..60 MHz.

        Parabolic dishes need to be several wavelengths across to exhibit significant gain. EG: 1MHz has a wavelength of 3e8/1e6 = 300 metres. So for 1MHz, a single dish would probably need to be at least 1kM in diameter. This is a big ask, even for NASA. (and, in the kHz range, even the whole moon isn't big enough!)

        The type of astronomy that can leverage reasonable size parabolic reflectors is at a muc
    • I would not build them on earth and transport. I would simply build them out of the material on the moon. It really is the only way. Far cheaper and it will leave an infrastructure in place to build other things.
    • You could make a lunar telescope array far, far larger than anything you could park at the Earth-Moon L2.

      • by QuantumG (50515)
        But we won't.

        • Why do you say that? (Score:3, Interesting)

          by WindBourne (631190)
          If done in the right way, this could be used to build infrastructure on the moon. It seems to me, that if we BUILD a radio telescope on the moon, then the same machinery used to build that will go into building other structures such as a regular scope. In addition, if this is outsourced to somebody like bigelow, they will use that as a means of constructing a lunar base.
          • by QuantumG (50515)
            It's a chicken and egg problem. You need to have a large industrial base on the Moon before you can build anything significant and a large industrial base is significant.

            • I think that a few projects will kick start this. In particular, I think that bigelow will be there by 2016 (maybe 2015). I know that sounds like a wag, but I suspect that there will be strong financial encouragement for him to do so. In particular, I believe that the DOD will push us there, and will offer up incentives to bigelow to do it. Keep in mind that bigelow is expected to be out next year in some of the interesting x-prizes. From what I understand, they will be at the lunar digging one. That one co
              • by QuantumG (50515)
                Most no-one thinks the Google Lunar X-Prize will be won.. and that's just soft-landing a rover on the Moon by 2015.

                So a lunar base by 2015? Don't think so.

                Some sort of lunar resource utilization? No chance.

                If shit doesn't go down hill between now and 2050, we might expect there to be a "permanent" base on the Moon by then.. with two or three astronauts being replaced every 6 to 12 months - in other words, the ISS on the Moon.

                • Most no-one thinks the Google Lunar X-Prize will be won.. and that's just soft-landing a rover on the Moon by 2015. Hummmm. Everybody swore that America's space prize was un-winnable. And yet, I think that Musk will win it, with the remote possibility that several others could still do it. By the same token, I would be surprised to not see musk pursue the Lunar X-prize. The easy way is work with armadillo or perhaps blue origin. Why use one of those? Because they make a very nice lunar transporter.

                  Bigelow
                • by VENONA (902751)
                  But if you could somehow double that headcount, Starbucks would open a shop. That would drive launch costs down, allowing further expansion, etc. A virtuous circle.
    • The problem with high altitude lunar orbits is that they are unstable. The earth/sun tend to perturb them such that satellites would require significant orbit maintenance (aka lots of fuel, which eventually runs out).
  • by AIFEX (1036394)
    The universe is a huge place, what makes NASA think that our telescopes are able to see the "earliest stars and galaxies"? Or is this one of those "We are in the center of the universe" ideologies again?
    • by TrekkieGod (627867) on Thursday February 21, 2008 @07:50PM (#22510084) Homepage Journal

      The universe is a huge place, what makes NASA think that our telescopes are able to see the "earliest stars and galaxies"?

      The cosmic microwave background left over from the big bang as measured by WMAP [wikipedia.org] tells us the approximate age of the universe. Red-shift measurements tells us the distances of the stars we observe. The speed of light tells us how long it takes for the light of those stars to get here. Ta-da.

      Or is this one of those "We are in the center of the universe" ideologies again?

      We ARE at the center of the universe. So is everywhere else. The Big Bang wasn't an explosion that filled out existing space from which there's a center. Space itself expands from that point on, so the same infinitesimal point where the big bang started is the place where you're standing in now. The standard analogy is the surface area of a balloon as you fill the balloon up. There's just no preferred center.

    • Re: (Score:3, Interesting)

      Or is this one of those "We are in the center of the universe" ideologies again?

      From Ask an Astrophysicist [nasa.gov] :

      Question: If all the distant galaxies are flying away from us, does that mean that we're in the center of the Universe?

      Answer: Thanks for your question. Astronomers and physicists interpret the result that all distant galaxies are flying away from us as evidence for the uniform expansion of the Universe. In this case, any observer, at any location in the Universe, observes the same general motion: that the further a galaxy is from us, the faster its relative velocity with respect to the observer is. The famous (and very illustrative) example of this is to imagine a loaf of raisin bread as it is baking. The raisins in the bread spread away from one another as the loaf rises and expands during the baking. Pick any raisin and pretend you are standing on it (you're very small now!) and measuring the rate at which the other raisins are moving away from you. You will find that, no matter which raisin you choose, all other raisins appear to be moving away from you, with the furthest raisins receding the fastest.

      The current cosmological model of the Universe supposes that our position within the Universe is typical, not special. We are not located at the center of the Universe, but are rather taking part in its global expansion. I hope this answers your question.

      Regards,

      Padi Boyd
      for the Ask an Astrophysicist

      HTH.

  • ... different types of telescopes from quite a long way away.

    No. 1

    The LARC...The LARC.
  • are also being funded. Follow the last link [nasa.gov]

    I particularly like the idea

    Imaging nearby Earth-sized worlds using large telescopes with multiple instruments and separate spacecraft to block the light from these exoplanets' host star (Webster Cash, University of Colorado, Boulder; David Spergel, Princeton University, N.J.).

    This seems very cool - the idea is that you put a big screen out in space to block the light of the host star, but not that of the star's planet. This is not a new idea - the problem is diffraction around the screen (occulter). But it looks like Cash and Spergel have found a design that minimizes the diffraction.

  • NASA can't even afford to keep flying the shuttle, and they want to put a radio telescope on the moon? I guess they're allowed to dream.
    • That's kind of like saying I can't send the payments on my Honda because hiring a vintage limo to get to the post office is too expensive.

      Sorry, this discussion was strangely lacking in bad car analogies...
  • Why do they need to place the antenna? Could the build a thousand antenna in 'beachaballs' and just scatter them over the lunar surface. Then determine their positions by radar and compensate for the scatter in software.

  • Once the array is built, to help pay for the service, satelites will be placed in orbit around the moon to broadcast commercials every 15 minutes for rogaine, viagra, cialis and dietary supplements. For an extra $5 a month you can also get unlimited text messaging.
  • ...Oh wait, yes it is. My bad.
  • Some would say that the Earth is *our* Moon. But that would belittle the name of our moon, which is "The Moon".
  • Next Generation? (Score:2, Interesting)

    by His Shadow (689816)
    Didn't Sagan want this before the end of the Millennium? Could have been done, too.
  • Others have already pointed it out. Put the thing in an orbit of sorts, use relay satellite when behind moon. Use gyroscopes to perfectly smoothly track what you're looking at. No need to spend all that money landing on the moon. What a stupid idea, putting it on the moon. Obvious in your face money agenda. I guess the people buying it are stupid.
  • This interestingly reminds me of a book by Buzz Aldrin and John Barnes, "Encounter with Tiber" http://www.amazon.com/Encounter-Tiber-Buzz-Aldrin/dp/0446604046/ref=sr_1_6?ie=UTF8&s=books&qid=1203711161&sr=1-6 [amazon.com], which describes, among other things, getting normal citizens into space and putting a radio telescope on the dark side of the moon. It's good to see real life catching up with the SF authors.

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