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Analyzing Video Footage Of Collapse of Massive Arecibo Telescope

Discussion in 'Announcements & Open Forum' started by kopcicle, Dec 8, 2020.

  1. kopcicle

    kopcicle Sr. Member

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    bobl9355, Dmans and Handy Andy like this.

  2. Handy Andy

    Handy Andy Do Your Research First, Then Decide...

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    [​IMG]
    Also featured in the Movie CONTACT
     
  3. Slowmover

    Slowmover Elmer

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    Scuttlebutt is that Trump ended the treaty with an aliens group had Eisenhower had found agreement with in the 1950s.

    Arecibo damaged immediately thereafter.

    A further Trump move via US Space Force paralleled the second set of damages.

    Now declared irreparable. Condemnation in near future.
     
    Shadetree Mechanic and Crawdad like this.
  4. Crawdad

    Crawdad Well-Known Member

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    How's E.T. gonna phone home now?
     
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  5. Captain Kilowatt

    Captain Kilowatt Professional Amateur
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    Slowmover likes this.
  6. Crawdad

    Crawdad Well-Known Member

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  7. nomadradio

    nomadradio Analog Retentive

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    Demolition by neglect. Cables were clearly degraded by oxidation and wear. They had successfully stood up to every hurricane that hit PR.

    Came down with the wind dead calm.

    No technology is maintenance free.

    73
     
  8. AudioShockwav

    AudioShockwav Extraterrestrial Admin
    Staff Member

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    This was only a matter of time and they knew it.
    They do a lot of stuff with multi- arrays now.
    It was state of the art at one time but it was doomed from lack of money and foresight on maintenance issues.
    Sad to see a icon go.


    73
    Jeff
     
    Handy Andy likes this.
  9. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    I bet the insurance policy will cover it. They had to make sure that it wasn't an act of God that brought it down.
     
  10. Handy Andy

    Handy Andy Do Your Research First, Then Decide...

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    As with Arecibo, so will Chinas own, they are "Fixed" stationary, and have limited view of the sky.

    upload_2020-12-9_9-1-23.png

    Much like placing a Dobsonian Telescope of; say-a 24" mirror, of an F-stop of 4 - digging a hole, putting the mirror into that hole, then build a frame to allow the secondary mirror to an eyepiece - then allows you to stand there and look at the stars that will drift into view - but no way to "steer it" or even track.

    The Article talks about the "steering" ability, but they claim the "sensitivity" so to align and maintain "focus" of such signals may be a feat in itself - but like Arecibo - it will have limited view of the sky. It' has to wait for something to rotate into view in order to analyze it.

    That "depression" is only as good as it's ability to retain the shape to track, as and you get further and further from the overhead, you lose the ability to stay with the event and obtain any sort of resolution.

    Much like how reflection works, so does the Radio signals it is listening for. So the "array" at the parabolic foci is very narrow and circular (READ: Low Distorted phase angle sensing) but as the object they're studying rotates past Azimuth - the signal skews and drifts, this can generate an interference pattern the Dish can't compensate for - so it only has a limited window.

    The Arecibo had similar issues, but was able to utilize many different antenna frequencies so it's up to China to invest the funds needed to make the antenna foci array workable as well as steerable to reduce the "waveguide" interference patterns that form as the signals they are "focused" on from the object drifts by - even the echoes and Blue to Red shift that occurs - again to claim sensitivity may be great news, but you have limited aperture to work with.

    In a way both the Arecibo and FAST are "n-th Wonders" of the World, ranks right up there, but both contain limits to their ability to be useful - except maybe to send (attempt to) and communicate as Arecibo tried, but at the moment - the reception has been silent - it would be wonderful to know that the sensitivity it exhibits can overcome the aperture paradox.
     

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