Please do not call the Trisolarians.
China puts final touches to world's largest telescope
11–14 of 14 posts
Re: China puts final touches to world's largest telescope
#12Can someone explain the following to a relative layman to the science of radio astronomy? a) How much more can this accomplish in comparison to the well known Arecibo Radio Telescope? b) How is a fixed parabolic dish radio telescope different from a radio telescope array like Karl. G. Jansky Very Large Array? What are the relative pros and cons of one over the other? c) How do you 'steer' the telescope to look at dif…
Another reason this will accomplish more in comparison to Arecibo is that the National Science Foundation just ordered the environmental survey of how a full shutdown will affect the local environment.
It is believed in the astronomical community that the NSF wants to defund Arecibo and is just starting the process. [1] [2]
[1] http://phenomena.nationalgeographic.com/2016/06/04/uncertain...
[2] I've spent the last year about 20km from Arecibo and go to meetups and bars that some of the staff and scientists go to in order to talk shop.
Re: China puts final touches to world's largest telescope
#13The "Five-hundred-metre Aperture Spherical Telescope", or FAST, is the size of 30 football fields... This thing will look adorable when the Square Kilometre Array comes on line in 2020 and starts pumping many Petabits of data per second. https://www.skatelescope.org/signal-processing/ Oh look! They're hiring... https://www.skatelescope.org/people-contacts/vacancies/
Single-dish of this size has great sensitivity: it's a huge photon bucket. It doesn't need a long time on-source to make an image. So it is "FAST".
A telescope array is basically a huge structure with lots of holes in it. As the Earth rotates, the elements of the array sweep out arcs. That fills in some gaps. So even with a relatively bright source, you might need to wait a while before you fill in enough to be able to discern the details. So a big, single dish is "FAST".
Array elements are spread over thousands of meters. You get great resolution, like a microscope on the sky. But you also get all these diffraction patterns. Since you know the shape of your array, you can mostly solve for this, but it's a pain in the ass.
Re: China puts final touches to world's largest telescope
#14Someone ought to make a shouldwelearnchineseyet.com page.