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Space Science

Prototype Telescopes Complete Key Test 78

Posted by CowboyNeal
from the if-this-trend-continues dept.
Matthew Sparkes writes "Two prototype antennas for the world's largest array of millimeter-wave telescopes have passed a key test, working to track and image Saturn for more than an hour. Ultimately, ALMA (Atacama Large Millimeter/submillimeter Array) is expected to resolve details 10 times finer than the Hubble Space Telescope when it is completed in 2012."
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Prototype Telescopes Complete Key Test

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  • Server isn't responding to me. So I ask google. cache [209.85.165.104]
    • Text (Score:3, Informative)

      by Anonymous Coward
      Two prototype antennas for the world's largest array of millimetre-wave telescopes have passed a key test, working together to track and image Saturn for more than an hour on 2 March. Ultimately, ALMA (Atacama Large Millimeter/submillimeter Array) is expected to resolve details 10 times finer than the Hubble Space Telescope when it is completed in 2012.
      ALMA will use up to 64 antennas and will be located in the Atacama desert, 5 kilometres above sea level in the Chilean Andes. Designed to look through dust
    • well, (Score:1, Funny)

      by Anonymous Coward
      apparently, you've slashdotted Google.

      ---
      brought to you by the CAPTCHA "flamers"
    • by Chris6502 (857915)
      You could also go to the horses mouth: http://www.alma.nrao.edu/almanews/ [nrao.edu] Chris
  • by Anonymous Coward
    Ah, but can it image... Cassini?

    That would rock.
  • Will they.. (Score:2, Interesting)

    Censor the raw data coming from out of this too, like they have with the Hubble?

    I'm a ham operator, and the signals coming from the Hubble are a jumbled mass of unintelligible garble. Further research shows they are using military hardware for secure connections.

    I do understand that control codes are administered via ground, however, public key signing would allow transparency while providing a secure platform.

    Why do they hide the whole data stream? What do they not want us to see?
    • by Firethorn (177587) on Saturday March 10, 2007 @01:30PM (#18300550) Homepage Journal
      I have no problems believing that the control data is encrypted for the hubble. For one thing, you don't want others taking it over.

      As for the data, I'd imagine that it'd be compressed, encoded, and multiplexed to the point that you'd need special equipment that no normal HAM operator* would have, much less the settings needed to sort it all out and make sense of it.

      For public key stuff - that's more computationally intense than private key military encryption methods. Remember, we're talking about systems where a 386 would be considered 'high end'.

      *I'm not saying that you're a 'normal' Ham operator, Crawler, but we're talking the space industry here.
      • by Creepy Crawler (680178) on Saturday March 10, 2007 @02:05PM (#18300756)
        ---I have no problems believing that the control data is encrypted for the hubble. For one thing, you don't want others taking it over.

        No, of course you dont want some random joe to take Hubble over. However, they could implement in which "packets" are signed. The data would be separate from the authenticated signature. Along with that, they would want to implement a proper timecode to prevent replay attacks.

        But controlling is aside the issue.

        And I do hate to mince words but "normal HAM operator"... There isnt such a thing as a normal ham operator these days. Many hams specialize in one or two distinct fields of RF study. I like examining digital commms and remote communications (EME and meteor scatter).Along with my interests, I have bought that A/D board recommended by GnuRadio (normal HAM operator). All I needed was a RF front end and just to downsample to the range of the AD board (0-20 MHz).

        I asked for help from some people at NASA and they said the connection was encrypted, and it does seem to be the case.

        It doesnt really matter what Im required to build for receiving gear. It's all multi-purpose for us hams. And I do like the idea of splitting the transmitters from the receivers (well, you do have 2 antenna then per kit).

        ---I'm not saying that you're a 'normal' Ham operator, Crawler, but we're talking the space industry here.

        Too true. No offense taken. Still, I can decode the majority of transmissions (the old freq shift Symbol cards are really neat under a scope) and can transmit on quite a few bands. I dont know if you've ever been in a Ham's shack, but the amount of gear they can have (and I too) is pretty immense. I just focus on the digital side a bit more :-) .
        • Correction: recommended by GnuRadio (normal HAM operator). All I

          Damn clipboard. It was SUPPOSED TO BE (Measurement Computing PCI-DAS4020/12 A/D card).

        • Why dont you buy a telescope and see what they are trying to hide yourself?
        • Re: (Score:3, Insightful)

          by Firethorn (177587)
          Hmm... My extent of satellite experience was working with 8" floppies and multiplexors at Schriever AFB years ago, and more recently training in how to configure slightly more modern multiplexors for field applications. Fun time: spending three hours troubleshooting while in chem gear only to have the instructors realize that their satellite simulator(couldn't get real sat time for the exercise) had been jarred out of position.

          No, of course you dont want some random joe to take Hubble over. However, they
          • I hate to respond to a dead article, but you are spot on.

            ---Remember what I said about military private-key encryption being cheaper computationally?

            I remember seeing special chips when I was with my dad at a naval reserve center (he's a retired chief).. One of the things Im interested in is TEMPEST and such technology dealing with EMP. What I saw was impressive: Ceramic CPUs. They wernt made out of silicon (or that look anyways) but instead they were pearlish white and said to be immune to EM pulses.

            From w
      • by Tablizer (95088)
        control data is encrypted for the hubble. For one thing, you don't want others taking it over.

        I am kind of curious to see what Mr. Goatse would do with it for a day. (But tell me about it instead of show me.) Cue the Uranus jokes...
                           
    • by jpellino (202698) on Saturday March 10, 2007 @02:11PM (#18300784)
      Hubble releases public images, but much of the research is just that - research - done by labs who are trying to maintain the integrity and proprietary nature of their work. Hubble data is supposed to go to the researcher first and the public second. IIRC it's a default six month delay unless overridden by the lab collecting the data. It's not censorship so much as embargo, and it's really no different from what any researcher does in order to not be scooped on the research they're doing.

      • Re: (Score:3, Interesting)

        ---Hubble releases public images, but much of the research is just that - research - done by labs who are trying to maintain the integrity and proprietary nature of their work.

        I want you to realize that I am a US citizen and who pays his taxes. I speak from my American view: WHY is governmental science proprietary? Above all other things, science done by the government or by government money should be either 100% public domain, or the % of profits should be returned to the people (Im thinking of public uni'
        • Re: (Score:3, Insightful)

          by Teun (17872)
          It seems you forget that your tax money bought more than just the Hubble Telescope, the deal includes the scientific institutions that add value to the raw data.
          Many of these institutions bring their own budget and they want Value for Money, they need, for a period of time, to have some exclusive access.

          I'm sure that when you bring a juicy enough budget and the credentials for high-level research you can have a set of keys to decrypt the data first hand.
        • by Gerzel (240421)

          --I want you to realize that I am a US citizen and who pays his taxes. I speak from my American view: WHY is governmental science proprietary? Above all other things, science done by the government or by government money should be either 100% public domain, or the % of profits should be returned to the people (Im thinking of public uni's here). --Creepy Crawler

          Unfortunetly being a US citizen and paying taxes does not give you the government's consideration. You didn't pay for the politician's election camp
        • by Greg Lindahl (37568) on Saturday March 10, 2007 @04:57PM (#18301792) Homepage
          The astronomy community does exactly what you're asking for, you're just not listening:

          * The data is made available to everyone after a short time delay

          * The software to reduce the data is given away for free

          * Our papers are generally available for free at http://lanl.arxiv.org/ [arxiv.org]

          The point of the short delay is that the person who made the effort to write the proposal to get the telescope time deserves a reward: a short time to write the first paper about the results.

          If you look at other branches of science, they aren't nearly as good. But you're flaming your friends.
          • Re: (Score:3, Interesting)

            by Cid Highwind (9258)
            * The data is made available to everyone after a short time delay

            We *assume* that the data are made available after a short time, but because of the encryption there's no way to correlate released data with observed transmissions from HST. Some people accept NASA's word on this, others don't.

            Let me put it this way: Given the present theocratic leanings of the US government, if NASA found something that fundamentally challenged our notion of our place in the universe (like, say, one of the Mars rovers found
            • It wasn't clear that you're a nut until this posting; now it's overly clear. Shame on me, I suppose.
              • by fifedrum (611338)
                really, cripes the guy had a point until that rant exposed the tin foil wrapping his head.
              • Actually I just play one on the internet.

                Anyway, learn to read, I'm not the same poster you were arguing with above.
        • They do share it. But they worked hard to be able to use it and they get to be in line ahead of you.

          Scientists doing basic research do in fact collaborate, cooperate and compete, as it best serves the task at hand. That would explain the whole peer review process, not to mention the rampant cross-pollination of people between labs, projects, funding sources, large scale projects, etc.

          The vast majority of the results do get back to the public, you benefit from them, and they are shared.

          I pay my taxes too -
    • I don't know the reasons why hst uses an encrypted data stream, but it is in line with their policy regarding the public release of data. The principal investigator for the observations has a 1 year proprietary period on the data. This is because it represents a lot of work to plan in detail how the observations should be carried out and to justify the observations to the time allocation committee - so if you do the work of figuring out how the observations are to be done and why they should be done, you ge
    • by Chris6502 (857915)
      You are comparing apples with oranges here. The entire "data stream" is available to anyone with a suitable dish and receiver. Unless of course the targets decide to encrypt their natural RF emissions.

      Once the data has been captured it will become available after a proprietary period during which the principal investigator will have exclusive access to it. I believe this period will be one year.

  • Call me back when they complete the Turing test.
  • Apples and oranges (Score:5, Insightful)

    by $RANDOMLUSER (804576) on Saturday March 10, 2007 @01:30PM (#18300556)

    Ultimately, ALMA (Atacama Large Millimeter/submillimeter Array) is expected to resolve details 10 times finer than the Hubble Space Telescope when it is completed in 2012.
    Except that one is a radio telescope and one is an optical telescope.
    • Re: (Score:3, Informative)

      by jcorno (889560)
      Except that one is a radio telescope and one is an optical telescope.

      So what? Stars and other black bodies radiate in both visible and microwave. If you're trying to resolve nearby objects (like binary stars or planetary systems), either one will work. Resolution is resolution. And besides, the angle resolved by a telescope is proportional to wavelength, so that just makes it MORE impressive. This telescope has a better resolution than the Hubble, even though it's working with 1000 times the waveleng
      • by strider44 (650833)
        The difference is that radio telescopes don't have to be a mirror - they can even just be a mesh. Radio telescopes are relatively really easy to make - there's no real precision to them, an interferometer is easy to make so resolution is usually not a problem. Optical telescopes on the other hand, do require mirrors and they must be almost perfectly flat. To complicate things, you can't just get a mirror like those in your bathroom because glass is a liquid and this means that if you make it out of glas
        • by strider44 (650833)
          Apologies in clicking reply too soon. The last line should read:

          So in other words, we already have radio telescopes (or rather telescope arrays) with larger resolutions than hubble, and the level of technology required in building large optical telescopes is simply miles ahead of the radio telescopes.
    • Re: (Score:3, Interesting)

      Except that one is a radio telescope and one is an optical telescope.

      So? ALMA images the universe in different wavelengths than Hubble/Spitzer at al, but can do so at very high resolution. What really matters is how many wavelengths your aperture is. An 18 km baseline at a 1 mm wavelength is more wavelengths across than a 2.2 meter mirror at 600 nm. A lot of the highest resolution imaging is done with aperture synthesis nowadays, whether it's astronomers doing long-baseline interferometry, or using synt

  • by N3wsByt3 (758224) <Newsbyte&freenethelp,org> on Saturday March 10, 2007 @01:32PM (#18300568) Homepage Journal
    I'm actually beginning to wonder if space-telescopes still have their use (in regard to costs/benefits). I mean, thanks to interferometry one can get the resolution (equal or better) with earth based telescopes for a fraction of the price of space-telescopes like hubble and consorts. And thanks to adaptive optics there is hardly any atmospheric blurring which smears out the pictures anymore, neither. And, since the mirrors can be bigger then those send into space, the light-gathering power is way superior for earth-based telescopes.

    The only advantages left are for specific wavelengths (like near-infrared), because the atmosphere absorbs most of that, but even that is more and more debatable, now that new instruments and detectors are becomming so sensitive that they can detect and use it on Earth too. I'm wondering, with the multi-billion costs of space-telescopes, if it's really worth the money? With the same amount of money, one could make a huge interferometer-telescope with a diameter of the Earth (though it would need to consist out of many 10-meter telescopes for light-gathering purposes). I'm all for space-exploration, but what still justifies the expense of a space-telescope, if earth-bound ones can do as well for a fraction of the price?

    • Re: (Score:3, Insightful)

      by Falladir (1026636)
      The people who design and build these telescopes don't have unlimited budgets. If they use up their grant money sending a telescope into space, they can't hire as many graduate students, for instance. While saving money isn't the primary concern for the principal investigator, it's certainly a priority.

      The reason WMAP was a space telescope was, as you said, so that it wouldn't have to look through the water-vapor in the atmosphere. ACT [princeton.edu] and ALMA will be earth-based because it's impractical to send tele
    • by Tablizer (95088) on Saturday March 10, 2007 @01:44PM (#18300632) Homepage Journal
      I'm actually beginning to wonder if space-telescopes still have their use

      It is hard to separate hype from reality. Hubble is used as the benchmark in many claims because of its popularity. But as you partially pointed out, there are some rough-spots in Earth-based techniques:

      * Spectrum coverage: some important frequencies are blocked by the atmosphere.
      * Ecology: Earth scopes are accused of messing up mountain peaks and views and "sacred lands".
      * Guide-stars: Some earth-bound techniques require bright guide-stars near a scene to compensate for atmospheric distortion. This limits their use in dim portions of the sky.
      * Southern hemisphere: It is hard to see all portions of the sky well from any given point on Earth.
      * Newness: Many of the hi-res earth-scope techniques are new and complicated. Without a reference point, such as Hubble images, they may be collecting unintended artifacts of the technology.

      But it is an interesting issue to consider.
             
      • by SeaDour (704727)
        Not to mention the increasing prevalence of light pollution and radio wave interference. Aside from asking everyone to turn everything off, space-based observatories are the only way to counter this problem.
        • by Tablizer (95088)
          Not to mention the increasing prevalence of light pollution and radio wave interference. Aside from asking everyone to turn everything off, space-based observatories are the only way to counter this problem.

          But "floating" space junk has been pelting Hubble, so space is polluted also.
               
    • by Gil-galad55 (707960) on Saturday March 10, 2007 @01:52PM (#18300682)
      Land-based telescopes are gaining much ground, especially when it comes to data volume. The dataset for the LSST (Large Synoptic Survey Telescope) will most likely be measured in exabytes when all is said and done, and it simply isn't possible to send that volume of data home via telemetry. However, space-based telescopes most definitely have their place.

      Two exciting ones are Planck, which will make extremely precise measurements of the CMB (Cosmic Microwave Background) and--if we're lucky--LISA, a gravity wave telescope that will open a completely new part of the universe to us. The science prospects for LISA are staggering, and it is simply impossible to build an interferometer with a 5 million km arm length on the ground!

      • Re: (Score:1, Interesting)

        by Anonymous Coward
        One point to consider. Radio-frequency and ligth polution. If you look at a map from the earth at nigth
        you see almost no free spot in the northern hemisphere for an optical telescope. Also, radio-frequency polution
        will give the VLA and similar a hard time in years to come. This could be justification to go to space
        (maybe the moon?). So far, Chile is the best place to put a telescope.
      • The science prospects for LISA are staggering, and it is simply impossible to build an interferometer with a 5 million km arm length on the ground!

        Um, the circumference of the earth at the equator is 40,076 km. The average distance to the Moon is 382,500 km. I'm not sure this LISA can be built, in space or not. I know it supposed to be three probes hovering 5 million km apart with no physical connection, but keeping their positions reletive to each other accurate over those kind of distances would be no
        • It's absolutely non-trivial to do, but well within current capabilities. Just to blow your mind a bit, LISA must be sensitive to changes in arm length on the order of picometers... when the spacecraft are so far apart that round trip time for the light is 33 seconds! The only really tricky part in all of it is eliminating systematic errors from interactions with the LISA test masses and the spacecraft, but there has already been some testing done on test mass/spacecraft interaction, and they show the nois
    • Re: (Score:2, Interesting)

      by ajpr (921401)
      In a lot of bands you can't see anything through the atmosphere.

      Also if you are looking for chemical signitures (oxygen, methane) etc then you will have problems with the atmosphere again.

      Space also gives you 24 hour observation, obviously not possible on the earth during the day. Apart from that you get a free vaccuum which will help in keeping the instrument cool. This is useful for all observations, not just infra red (although it is particularly good for that). Ground based telescopes are more suited to
    • Re: (Score:3, Informative)

      by Nyeerrmm (940927)
      The idea of using interferometry is really interesting. The idea of an earth sized telescope is great. In fact, in Texas there is an attempt to build a Texas-sized interferometer with amplitude interferometer based on the Hanbury-Brown-Twiss effect. Basically the goal is to have universities or other entities across the state erect their own telescopes (we're using 16-inchers) which they will own and operate on their own, and then have a network set up where anyone can take over and run them. Hopefully
    • Re: (Score:2, Insightful)

      by thrawn_aj (1073100)
      You forget light pollution, which is a major problem for ground-based telescopes. That's precisely why LISA and LIGO can work on the ground - they're not measuring light, they're trying to measure gravity waves, which (we hope) are strong enough to show up in the interferometer. Space is better for another important reason, especially for new telescopes: it is VERY cold in space (~2.7K). This means you can use superconducting wires with impunity and without the need for a coolant. That itself should be a si
    • I'm all for space-exploration, but what still justifies the expense of a space-telescope, if earth-bound ones can do as well for a fraction of the price?

      I'd like to see an array of space based telescopes set out in a pattern much bigger than the Earth, perhaps at the L2 LaGrange point. That should allow us to see planets in other solar systems quite well.

      I don't see how you can do that on Earth.
  • Why not put a bunch of little telescopes in space. Best of both worlds.
  • Here's the real question: Which will roll out first, the completion of all US television broadcasts in high definition or this thing being launched, orbiting, and operating?
  • Ultimately, ALMA (Atacama Large Millimeter/submillimeter Array) is expected to resolve details 10 times finer than the Hubble Space Telescope when it is completed in 2012.
    Great. It'll be completed just in time for the end of the world [wikipedia.org]!
  • How cheap/easy would it be to make a distributed radio telescope if we had lots of small systems scattered around?

    I was envisioning a small unit that plugs into a PC and has GPS location ability so we know where it is in the array, and the software reports data and location back to the central system. If everyone interested in astronomy picked one up we'd soon have a big array, and it would be reasonably low cost too if everyone paid to cover some of the cost of their antenna.

    I suspect if we have enou

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