Questions regarding structures designed to aid in the observation of astronomical objects.

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1answer
172 views

Do primary mirrors in large observatories undergo regular removal and re-coating of the aluminum? Why?

Performance of astronomical mirrors that are exposed to the environment for long periods of time can experience a slow degradation of performance. They usually need to receive some kind of regular ...
3
votes
1answer
46 views

When did “resilvering” large telescope mirrors actually refer to aluminization, and why was it necessary?

This answer nicely summarizes the general picture of historical use of silver for mid to large size telescope mirrors, and the shift to aluminum once good quality vacuum pumps and chambers suitable ...
5
votes
1answer
72 views

Was the use of silver on 'optical' telescope mirrors more common in the past? Why?

In the past, weren't many astronomical telescope mirrors periodically removed and 'resilvered', and wasn't this actually done using silver? I'm guessing that this is much less common now - new ...
6
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1answer
87 views

What is a quaternary mirror and why does the E-ELT need one?

In this recent BBC article I read the one-sentence paragraph: "Development on the mirrors - in particular, a very complex quaternary mirror - continues apace." and became interested in the ...
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0answers
25 views

Adverse effects of urban growth on old astronomy observatories? Need article/book

I am looking to get some information on the adverse effects of urban growth/light pollution on the oldest/traditional observatories of the world (europe). Can anyone recommend me books or articles to ...
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0answers
31 views

Pyramid shaped observatories

There are some pyramid shaped observatories around the world, like the Solar Lab Pyramid (1) in the Canary Islands or The Pyramid International Laboratory (2) in Nepal. (1) (2) I was wondering, ...
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0answers
19 views

How will the Breakthrough Initiatives affect other astronomy observations?

BACKGROUND The Breakthrough Initiatives is in the news because of a $100 million private donation for a SETI project. It doesn't seem to be for building any new observatory (but maybe for buying ...
5
votes
1answer
92 views

What makes a really good observatory site, besides altitude?

Let's limit this to optical telescopes. I understand that the higher you are, the less atmosphere is above you to get in the way of observations. From reading around, there seem to be a few more but ...
5
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1answer
40 views

Tools for creating a multiwavelength view of the sky

Not sure that this is the correct place to ask this question, but here goes. I am trying to find tools to accumulate image data (preferably in FITS format) on a given (RA, Dec)-coordinate of sky. ...
7
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3answers
1k views

Why do astronomers like green laser pointers? [closed]

When I've been to Astronomy-nights for the public at the local observatory, they always used green lasers to point things out. Why is there such a preference for green lasers? What's wrong with red ...
2
votes
1answer
893 views

How do I calculate the velocity dispersion of a galaxy given an integral field spectrograph?

I couldn't find on the web how to get the velocity dispersion and velocity maps of galaxies from the 3D data cube that I get from the integral field spectrograph.
7
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1answer
112 views

What is the current routine of modern astronomy? [closed]

With about all visible stars catalogued, measured and photographed it seems that chapter is closed. I realize currently while amateur astronomy is big on cataloguing all asteroids in the Solar System, ...
7
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1answer
58 views

What are the metrics of observation conditions?

How do professional astronomers measure and describe (ambient) observation conditions? I know smog, light contamination from the city lights, fog, clouds, rain/snow, humidity etc all contribute ...