China's colossal radio telescope begins testing

http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this thing find what the other couldn't?

StarDust wrote:
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this
thing find what the other couldn't?


Perhaps objects in the northern sky?

On Sunday, September 25, 2016 at 1:19:22 PM UTC-7, Mike Collins wrote:
StarDust
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this
thing find what the other couldn't?


Perhaps objects in the northern sky?

Both are South!

StarDust wrote:
On Sunday, September 25, 2016 at 1:19:22 PM UTC-7, Mike Collins wrote:
StarDust
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this
thing find what the other couldn't?


Perhaps objects in the northern sky?

Both are South!


It's in the northern hemisphere.

On Sunday, 25 September 2016 12:27:39 UTC-4, StarDust wrote:
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this thing find what the other couldn't?

Aside from the fawning, a---kissing of China (which the left is apt to do) it doesn't really address much about how the antenna will work. It's non-steerable for the most part. Would be interesting to know about resolution, what its range of operation is.

On Sun, 25 Sep 2016 14:00:35 -0700 (PDT), RichA
wrote:

On Sunday, 25 September 2016 12:27:39 UTC-4, StarDust wrote:
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this thing find what the other couldn't?

Aside from the fawning, a---kissing of China (which the left is apt to do) it doesn't really address much about how the antenna will work. It's non-steerable for the most part. Would be interesting to know about resolution, what its range of operation is.

It is steerable over an 80° cone- twice the angle possible at Arecibo.
It is parabolic (as opposed to the spherical dish at Arecibo) which
provides higher spatial resolution (the surface is deformable, so the
parabolic shape is created based on the part of the sky being
recorded). Both telescopes have about the same aperture and focal
length, so most of their physical characteristics are similar.

On Sunday, September 25, 2016 at 2:41:19 PM UTC-7, Chris L Peterson wrote:
On Sun, 25 Sep 2016 14:00:35 -0700 (PDT),

On Sunday, 25 September 2016 12:27:39 UTC-4, StarDust wrote:
http://www.bbc.com/news/science-environment-37453933

So, we all ready have one giant radio dish in S-America, what will this thing find what the other couldn't?

Aside from the fawning, a---kissing of China (which the left is apt to do) it doesn't really address much about how the antenna will work. It's non-steerable for the most part. Would be interesting to know about resolution, what its range of operation is.

It is steerable over an 80° cone- twice the angle possible at Arecibo.
It is parabolic (as opposed to the spherical dish at Arecibo) which
provides higher spatial resolution (the surface is deformable, so the
parabolic shape is created based on the part of the sky being
recorded). Both telescopes have about the same aperture and focal
length, so most of their physical characteristics are similar.

Can listen to satellites too!

On Sunday, 25 September 2016 23:41:19 UTC+2, Chris L Peterson wrote:
Both telescopes have about the same aperture and focal
length, so most of their physical characteristics are similar.

Is that remotely true? 300:500 meters aperture is a large difference in scale.

An increase from a 12" to an 18" telescope would be a big deal for many amateurs.

On Sun, 25 Sep 2016 22:47:16 -0700 (PDT), "Chris.B"
wrote:

On Sunday, 25 September 2016 23:41:19 UTC+2, Chris L Peterson wrote:
Both telescopes have about the same aperture and focal
length, so most of their physical characteristics are similar.

Is that remotely true? 300:500 meters aperture is a large difference in scale.

An increase from a 12" to an 18" telescope would be a big deal for many amateurs.

Not sure of the details, but apparently it only uses about 300 meters
of its total 500 for collecting energy. I'd guess it's related to the
way the pickup moves around- if you're shifted off a full 40° from the
center, and you're maintaining a circular, parabolic collection area,
you're going to lose a lot of the total surface. So presumably the
secondary is picking up off the smaller area.

On Monday, September 26, 2016 at 1:47:25 AM UTC-4, Chris.B wrote:
On Sunday, 25 September 2016 23:41:19 UTC+2, Chris L Peterson wrote:
Both telescopes have about the same aperture and focal
length, so most of their physical characteristics are similar.

Is that remotely true? 300:500 meters aperture is a large difference in scale.

An increase from a 12" to an 18" telescope would be a big deal for many amateurs.

Herschel's 18-inch telescope was only a 12-inch by today's standards.

The "similarity in physical characteristics" between these two radio telescopes ends with the observation that they are both really big.