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Telescope Cluster For SETI

Posted by Hemos on from the soon-we-will-contact-my-home-planet! dept.

ContinuousPark writes: "MSNBC is reporting that radioAstronomers showed today the Rapid Prototype Array, which consists of seven 12-foot off-the-shelf satellite dishes, set up at the Russell Reservation near Lafayette, CA. This experiment, in which computer software will control the drive systems of the dishes and process all gathered information, is going to tell astronomers how to build much bigger radio telescope arrays such as the 1-hectare telescope and the Square Kilometer Array; the SKA would be 10 to 100 more sensitive than the Arecibo radiotelescope. Check out the SETI Institute press release and photos. "

5 of 60 comments (clear)

  1. Cool! by dlc · · Score: 3
    • The seven-dish prototype unveiled today is a precursor to what will eventually be an array of hundreds, perhaps thousands of small backyard-type satellite dishes linked by sophisticated electronics to create an unparalleled SETI observing instrument

    So, once this is fully in place, not only will they have folks all around the world crunching numbers for them, but they'll have folks all around the world listening for them as well. Now *that's* cool.

    It makes sense, though. One of the arguments for helping SETI was that your computer is idle most of the time. Similarly, your satellite dish is also idle most of the time; why not make use of it?

    Now, if I only had a satellite dish...

    darren


    Cthulhu for President!
    --
    (darren)
  2. Resolution vs. Sensitivity by meckardt · · Score: 3

    While it is true that the energy gathering capability of the smaller dishes is much less than the large antenna at Arecibo, the resolution of the signal is not a factor of the gathering area so much as the position of the antenna. 100 12' dishes scattered over 1000 miles would act like a 1000 mile dish, except that the actally intensity of the signal would not be as great.


    Gonzo
  3. Revolutionarry? by pe1rxq · · Score: 3
    What is so revolutionarry about this? (Not that I don't like the idea) but building antenna arrays is nothing new, it has been done for years.

    And making the thing 'expandable' is not really revolutionarry in my opinion.....

    Grtz, Jeroen

    --
    Secure messaging: http://quickmsg.vreeken.net/
  4. As a friend of mine said... by Alien+Perspective · · Score: 3
    ..while visiting Arecibo:
    "once you've seen one 300 meter radio dish, you've seen 'em all!"

    To put this in perspective, you need to have 6,824 of the little 12 foot dishes to equal the collection area (and hence sensitivity) of Arecibo...

    ..assuming that you can combine all of those signals without preamp noise killing your S/N ratio. The "S" for the 1000's of little dishes might be the same, but you'd have 1000's of preamps contributing to "N", rather than one.

  5. Optical SETI by lythari · · Score: 4
    A Recent development in the SETI programme is optical SETI. As the name suggests, this attempts to detect any transmitions sent using light in the visible part of the spectrum. The concept for optical SETI isn't new. However, it was only recently that it has been put into practise. The latest issue of the Planetary Report (the bimontly magazine of the Planetary Society) has an article of Optical SETI which I will attempt to summarize below. The advantages of sending signals using visible light over radio waves are

    1)transmitted beams of visible light (ie. lasers) can be finer than beams of radio waves due to the higher gain of optical telescopes. I suppose this means that the signal can be more concentrated and thus brighter and more easily detected.

    2)visible light doesn't disperse as much as radio waves. This also increases the intensity of the signal.

    3)the capabilities of radio transmitters has hit a brick wall while optical lasers continue to increase in power. This is assuming that an alien race is similarly limited as to the power of their radio transmitters. All this leads us onto the question of how effective signals sent with visible light are. The answer is very. The article says that with our current technology, we can send laser transmitions that would outshine the background light from our sun by 5000 times. So assuming that an alien civilisation has more powerful lasers than us, we should easily be able to detect any signals they send in our direction.

    Also, the equipment needed for an optical SETI search is very simple. All it involves is a pair of photon-detectors. Current optical SETI equipment works on the premise that any optical signals from alien civilisations will be sent in pulses. I haven't had time to purse the explanation on how the detector works so I can't tell you yet. Perhaps someone else with access to the latest Planetary Report could help out here.