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Science Forum

  1. Standard member sonhouse
    Fast and Curious
    25 Sep '16 13:55
    http://phys.org/news/2016-09-china-world-largest-radio-telescope.html

    Twice the sensitivity of the 300 meter Arecibo scope in Puerto Rico and better resolution.

    We will see what it discovers.
  2. 25 Sep '16 15:38
    I wonder how it compares to the SKA. The SKA has the advantage of being able to turn the dishes. I believe fixed dish telescopes can achieve some movement by moving the antenna, but I would expect that would affect the focus.
  3. Standard member sonhouse
    Fast and Curious
    25 Sep '16 17:42
    Originally posted by twhitehead
    I wonder how it compares to the SKA. The SKA has the advantage of being able to turn the dishes. I believe fixed dish telescopes can achieve some movement by moving the antenna, but I would expect that would affect the focus.
    Moving the pickup antenna doesn't effect focus because the dish net is circular. That lowers the effective collection area but means you can move the antenna around with no loss of focus. A parabolic dish would have more gain and resolution but you would have very little motion available for the antenna collectors since the parabolic dish focuses on one point. So a circular dish combined with moving antenna partially solves that problem. The left over is the antenna only has about 15 degrees of freedom but that is enough for most studies.
  4. 30 Sep '16 21:48 / 1 edit
    Originally posted by sonhouse
    http://phys.org/news/2016-09-china-world-largest-radio-telescope.html

    Twice the sensitivity of the 300 meter Arecibo scope in Puerto Rico and better resolution.

    We will see what it discovers.
    One of its costs was relocating more 9000 people (they were mostly poor and had no choice)
    who had lived within 5 km of the project. These people were given about 1800 USD
    (with some perhaps more) as 'compensation' for being deprived of their homes.

    In contrast, native Hawaiians (who regard Mauna Kea as a sacred site) and environmental
    activists are campaigning to have the astronomical observatories atop Mauna Kea closed.