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UK Upgrades Radio Telescope Network

armacc writes "From the BBC, work has started to use optical fibres to link up the giant radio telescope at Jodrell Bank with five others that are scattered across England. The telescopes comprise an array called Merlin that combines the data from each so they perform as a larger telescope. The telescopes are currently linked by microwaves but replacing them with optical fibres will be a revolution. Astronomers say the new project, e-Merlin, will be a great leap in Jodrell Bank's ability to look out into space."

21 comments

  1. Jodi's listening by Anonymous Coward · · Score: 3, Funny

    Jodi Foster's listening. She's going to hear something and build a giant flimsy gyroscope just so she can see dear ol Dad again.

  2. But even with the upgrade by Eevee · · Score: 4, Funny

    They still won't notice the Vogon constructor fleet.

  3. How far back... by Mick+Ohrberg · · Score: 2, Interesting

    ...(or how far out) will they be able to spy with this puppy? I find it very interesting that we've come so far in the understanding of space, but we still have but scratched the surface. I would love to be able to hibernate for say 100 years, and then find out where we're at in technology, space flight and exploration...

    --

    Quidquid latine dictum sit, altum sonatur.

    1. Re:How far back... by Mick+Ohrberg · · Score: 0, Offtopic

      Ugh, mod parent down -200 please. :/

      --

      Quidquid latine dictum sit, altum sonatur.

    2. Re:How far back... by Jon+Chatow · · Score: 1

      From the radio programme covering the story (it was part of the Leading Edge broadcast on Radio 4 thie evening), 10 billion (10^9) light years (and hence, obviously, 10 billion years).

      --
      James F.
  4. How far back... by Mick+Ohrberg · · Score: 0, Redundant

    ...(or how far out) will they be able to spy with this puppy? I find it very interesting that we've come so far in the understanding of space, but we still have but scratched the surface...

    --

    Quidquid latine dictum sit, altum sonatur.

  5. Current and future telescopes. by Christopher+Thomas · · Score: 2, Informative

    ...(or how far out) will they be able to spy with this puppy?

    The ability to see great distances requires a large number of photons to be collected (to pick up faint signals and better separate signal from noise), which requires a large aperture area. They're not getting that here, so they won't be able to see much farther.

    What they _do_ get by using radio telescopes in tandem is a much larger effective aperture _diameter_, which lets them resolve finer details. What was once a blob or a point source of radio waves, now resolves into jets from an active galaxy, or what-have-you.

    This doesn't require a fiber link (they're using microwave links to exchange data between the Merlin telescopes now), but a fiber link lets them transfer more data and so do the data processing a bit more efficiently. Same telescope array, better throughput (so more of the captured data can actually be analyzed).

    I find it very interesting that we've come so far in the understanding of space, but we still have but scratched the surface. I would love to be able to hibernate for say 100 years, and then find out where we're at in technology, space flight and exploration.

    For telescopes, you won't have to wait more than 50 years, tops. Optical intereferometric telescopes have been built that do much the same kind of thing that these radio telescopes do (huge effective aperture diameter from many smaller telescopes, letting you see relatively bright objects in fantastic resolution). Space-based ones are in the planning stages now, and will be launched well within your lifetime. This will allow us to do detailed surveys of nearby solar systems.

    A sun-orbiting array of radio telescopes would also be useful, for similar goals (and to make really accurate maps of our own galaxy's interior, and give a better idea of the structure of nearby galaxies). No idea if anything like this is on the drawing board just yet. If anything, it'd be much easier than an optical array.

    Technology-wise, we're likely to have mature materials and fabrication technology 100-150 years from now, either through nanotech or through more conventional synthesis techniques. That will let us build just about anything we want to that's within the theoretical limits of materials built from ordinary matter. We'll also likely have true AI. Whether the world looks like an updated version of our current one, or whether we go through a Vinge-style singularity into a very different type of world, is something our grandchildren will find out (I'd like to live that long, but I'm not going to bet on it just yet).

    1. Re:Current and future telescopes. by Mick+Ohrberg · · Score: 1

      Development of technology is amazing. I read somewhere a long time ago about and engineer (I think) who said his mother (I think) was afraid that we will lose control over the computers in a near future. His reponse was that this was very unlikely to happen, but he did believe that we already have lost control over development and technology advancements. Along those lines - how long until we have a telescope that can see far out/back enough that we can "see" the events even closer to da big boom?

      --

      Quidquid latine dictum sit, altum sonatur.

    2. Re:Current and future telescopes. by Christopher+Thomas · · Score: 1

      Development of technology is amazing. I read somewhere a long time ago about and engineer (I think) who said his mother (I think) was afraid that we will lose control over the computers in a near future. His reponse was that this was very unlikely to happen, but he did believe that we already have lost control over development and technology advancements.

      Once we can reliably produce computers that are smarter than we are, it's only a matter of time before they dominate society's workings. This isn't necessarily a bad thing, but there's no guarantee we'll particularly like the resulting state of affairs either. It could also just as easily end up being us who are the computers (using AI technology to enhance our own thinking as readily as we build self-contained thinking machines). Whether we'd still count as "human" under these conditions is a matter of philosophy, not science.

      Very murky waters, and very difficult to predict which of the myriad of possibilities will actually happen.

      Re. technology development, we're definitely at a point where if something would be useful or even just interesting to do, someone will do it (look at human cloning). The resources required for research are readily available, and there is no practical way to establish ironclad control over all research in the world at this time. Couple this with national competitiveness, and you get relatively unhindered development. This may eventually change through any of several methods (we reach a brick wall where all research is expensive [unlikely], we finish researching everything that has a practical/commercial application [unlikely any time soon], we unify under a global government that can and does restrict research [unlikely any time soon]). Combine this with some technologies that drastically lower the bar to research and development (like nanotech, if it can work as well as hoped), and you get this state of affairs continuing or even getting more extreme.

      It will be interesting to see how it all works out.

      Along those lines - how long until we have a telescope that can see far out/back enough that we can "see" the events even closer to da big boom?

      There is a hard limit to how far back we can see - the point at which light and matter decoupled (when the whole universe was a plasma, it was opaque; when atoms formed, it became transparent). We can already see to this boundary in some bands. The cosmic microwave background, for instance, is the severely redshifted thermal radiation from this decoupling. Optically, if I remember correctly deep-field pictures went back a bit over 10 billion years, and the decoupling happened around 13 billion (or about 300k years after the big bang). So we're relatively close, but observation gets a lot more difficult at high redshifts (less energy reaches us, and there may not be bright, compact galaxies to see - though this itself would be a useful measurement to make).

      An astrophysicist/cosmologist can give you more detailed answers on this than I can.

    3. Re:Current and future telescopes. by barakn · · Score: 1
      The ability to see great distances requires a large number of photons to be collected (to pick up faint signals and better separate signal from noise), which requires a large aperture area. They're not getting that here, so they won't be able to see much farther.

      If you RTFAs you should have noticed numerous references to the increased sensitivity of the new system in addition to the increased resolution. Only 0.5% of the data can be transferred from one telescope to another over the current microwave link. The telescopes can't be effectively utilized together as one giant collecting area, thus limiting to the sensitivity to the collecting area of the individual telescopes. The microwave link wasn't for increasing the sensitivity, it was for interferometry. The fiber optics will allow the combination of all the data from all the telescopes, thus allowing increased sensitivity. That said, some of the new increase in sensitivity comes from improvement of the Jodrell Bank telescope's surface.

      --
      "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
    4. Re:Current and future telescopes. by Christopher+Thomas · · Score: 1

      If you RTFAs you should have noticed numerous references to the increased sensitivity of the new system in addition to the increased resolution.

      Unless they are linking thousands of telescopes, they are getting one *hell* of a lot larger boost in resolution than they are in light-gathering power by linking telescopes. S:N improves as the square root of light-gathering power, further reducing the resulting improvement in sensitivity.

      My point stands. Have a nice day.

    5. Re:Current and future telescopes. by R.Caley · · Score: 2, Insightful
      Unless they are linking thousands of telescopes, they are getting one *hell* of a lot larger boost in resolution than they are in light-gathering power by linking telescopes.

      If this was themlinking the telescopes up for the first time you'd have a pont, but they already have the resolution, they already to interferrometry on the array. They aren't, so far as I can see, adding extra, further away, telescopes to the array which is what would be needed for better resolution.

      --
      _O_
      .|<
      The named which can be named is not the true named
    6. Re:Current and future telescopes. by barakn · · Score: 1
      Your point stands? It doesn't have a leg to stand on.

      Dr. Philip Diamond, Director of the MERLIN/VLBI National Facility added: "In combination with the newly resurfaced 76m Lovell telescope, the upgrade will give a 30-fold increase in sensitivity.

      In fact, there are no references to the resolution increasing. This stems from the fact that the telescopes are already being combined together for interferometry and so the system is already at its max resolution. As /. user R_caley correctly noted, "They aren't, so far as I can see, adding extra, further away, telescopes to the array which is what would be needed for better resolution." Your confusion stems from the fact that the light-gathering area of two average scopes on the current network is only 1.005 times that of a single average scope (95.5% of the data from one is lost as it's transferred to the other), while you naively assume that the light gathering area is doubled.

      I'd say "have a nice day" if I didn't think you should have the kind of day you deserve.

      --
      "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
    7. Re:Current and future telescopes. by Christopher+Thomas · · Score: 1

      Your point stands? It doesn't have a leg to stand on.

      Let me spell this out for you.

      A data transfer bottleneck makes interferometry suck just as much as it makes light-gathering suck, because in both cases you're throwing away most of your data.

      An effective increase in signal-gathering capability by the factor of 30 you quote gives an increase in ability to distinguish signal from noise of about 5.5 (signal goes up as N, noise goes up as root N). This is piddling compared to the fact that, being no longer data-limited, you can take all of the interferometry measurements you like instead of having to play duty-cycle and array subset games to get around the network limitations.

      The article focused on photon-collecting capability. Good for it. Doesn't change the validity of my statements.

      Does this make things clearer?

  6. Use the things name Daggumit! by Syncdata · · Score: 2, Informative

    Rather than call it a "network of telescopes" or an array, call it by it's name, an interferometer.
    The state of science journalism is bad enough, but this is /., and I don't come here to have topics spoonfed to me with fourth grade vocabulary. Even the linked article refers to this "network of telescopes" by it's proper name.
    I know I'm nitpicking, but we have words for things, and we should use them!

    And in an effort to be ontopic, hooray for the efficient utilization of existing resources!

    --
    "Inattention makes clowns of us all" -Bean
    1. Re:Use the things name Daggumit! by Christopher+Thomas · · Score: 2, Interesting

      Rather than call it a "network of telescopes" or an array, call it by it's name, an interferometer.

      Calling it a "phased antenna array" is perfectly valid. Just depends on whether you're talking to an astronomer or an electrical engineer :).

      Also, I believe you're overestimating the technical savvy of most slashdot readers. Know thy audience.

    2. Re:Use the things name Daggumit! by barakn · · Score: 1

      I beg to differ. The data could be used for interferometry, or they could be simply added together for increased sensitivity. Calling the network an interferometer ignores one if its possible uses.

      --
      "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
  7. All you say is true by Syncdata · · Score: 1

    Phased antenna array is valid, but it's just as messy a term as inferometer to the layman, so why not just use the things name?

    And true, we are not all Edwin Hubble here on /., some people do come for the LOTR and stay for the science, but the title description of /. indicates the intended audience are of nerdish persuation. If a nerd can't go to a nerd website, and hear a nerdy term used in all it's nerdy precision, then where, I ask Where can that nerd go?

    It's like the nuggets you read about in forbes, or the times-picayune, about how many library of congresses can fit on a chip 1000th the size of a human hair. Save that baloney for the norms. I want to know how many terabytes of data it can store, and it's width in imperial units (with the mandatory conversion for our wayward metric brethren following).

    In closing, I'm a bitter, bitter man.

    --
    "Inattention makes clowns of us all" -Bean
    1. Re:All you say is true by Anonymous Coward · · Score: 0

      And in a hilarious twist, I misstype the name of the thing I'm so insistant on naming properly. Goodnight!

  8. Umm...it is an array. by astroboscope · · Score: 1
    Rather than call it a "network of telescopes" or an array, call it by it's name, an interferometer.

    IARA*, and "array", or "interferometric array", are the most commonly used terms, although interferometer is also used. The difference is that an interferometer can be just 2 antennas, while an array implies more than that, i.e. an interferometer that is an array is an array of interferometers. The more antennas, the better, because high quality imaging requires reasonable sampling of the area that the simulated "big dish" would cover.

    "Network of telescopes" is also OK, but not commonly used...except when writing an article for the general public.

    I Am a Radio Astronomer (working with the Canadian Galactic Plane Survey), but given the topic you could be forgiven for thinking that was "I Am an Array". ;-)

    --
    If we were ants living on a Rubik's cube, differential geometry would be a little more confusing.
  9. This is a general trend by Anonymous Coward · · Score: 1, Informative

    Several observatories working together have been using glass fibre connections to make international interfermetric observations (Very Long Baseline Interferometry); this mode hase been dubbed eVLBI. This is still a pilot, but is working well. Have a look at. http://www.evlbi.org/evlbi/te017/te017.html