What type of telescope requires the biggest dish mirror?
What type of telescope requires the biggest dish mirror?
To have their resolution compare to optical telescopes, a radio telescope’s antenna size needs to be much, much larger. The largest moving radio dish is the Green Bank Telescope, 100 meters across and fully-steerable.
What is a telescope mirror coated with?
aluminum
Most telescopes coat their mirrors with a very thin layer of aluminum. The exceptions are the Gemini Telescopes, which recently coated their mirrors with silver.
How long do telescope mirrors last?
With regular use the older coatings typically last about 10 years, while the newer enhanced coatings may last more like 20. But there are many variables that come into play.
Which glass is best for telescope?
Pyrex is slightly better than plate glass in theory, but not in practice. Ventilation is far more important. “Large telescopes are more impaired by light pollution than small ones.”
How can the Hubble telescope see so far?
Earth’s atmosphere changes and blocks some of the light that comes from space. Hubble flies around, or orbits, high above Earth and its atmosphere. So, Hubble can see space better than telescopes on Earth can. Then Hubble uses radio waves to send the pictures through the air back to Earth.
Is there a good source for mirror support?
There really is no one good source for modern mirror support information. Books have been published in the past, and even recently, give information on the topic, but much of the information is out of date. Other advice steers those who are looking for the highest quality mirror support methods in, what are in my opinion, the wrong directions.
How does edge support work on a telescope?
The edge support roller rotates slightly as the telescope moves up and down, and does not allow the edge support to pull on the mirror. If the edge support is positioned properly, the only force applied is into the mirror, towards its center, along the plane of the center of gravity of the mirror.
What kind of material do you use for a mirror?
3) Assuming the back of the mirror is fairly smooth, use low-friction contact points made from hard plastic, such as Delrin or Nylon, and machined smooth to match the back of the mirror. Teflon can cold-flow, and thus is not the best material for this.
What kind of contact points do you need for a mirror?
The primary mirror should rest on hard plastic contact points that have relatively low friction. Polished metal will work too, provided there is no chance of the mirror bouncing on them, as it might do in transport.
