Questions related to the physical instruments for astronomical observations.

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4
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1answer
160 views

What is the bluest narrow band filter mounted on ground based telescopes?

If we want to check a QSO's lyman alpha narrow band image, could a ground based telescope do that? I mean under the circumstance that its lyman alpha shifts to 3300A.
1
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1answer
43 views

When is Gamma Draconis closest to the zenith in London on April 4th

I am reading Roobert Hooke's paper An attempt to prove the motion of the earth from observations (1674, faksimile). Hooke writes The principal dayes of doing which will be about the 4 of April, ...
1
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1answer
65 views

Method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle?

What is the method to determine the amount of reflected starlight necessary for an exoplanet to be visible from a given distance/angle? (Not from occlusion but actually visible on its own.) Further, ...
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1answer
33 views

why are solar telescopes built on lakes? the site differnece between a solar and an optical telescope

According to the wikipedia page big bear, water can cool the observatory. Big bear is in the southern California. It is better to build it on a cold high mountain with stable and clear atmosphere? ...
2
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0answers
56 views

Is there a cosmic, rather than technological, upper limit to what a telescope can resolve?

Space radio interferometers could have a baseline of millions of kilometers, but is there a point where a larger baseline doesn't improve the resolution anymore because the photons observed are ...
2
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0answers
49 views

need data-point: actual counts per second with APD (avalanche photodiode) detector

I'm designing a sensor system to perform specialized [astronomy and space-sciences] experiments, and need a "reality check" to support or adjust my theoretical calculations. What I need is the ...
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0answers
47 views

Telescope Problems

I currently own a telescope, I'm an amateur astronomer and currently just trying to view the moon. I own the Celestron PowerSeeker 70AZ. Link for information on the telescope: ...
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0answers
57 views

If we built one hundred 3m telescopes and point them to a single star what would be the final resolution?

We'll mount all of them in a same location and connect them to each other (like VLT) so they will combined all the results and will produce some staggering images however my question is, would they be ...
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0answers
16 views

Can ground based telescopes use a starshade in space?

1) Could a starshade in orbit be used by ground based telescopes? If so, what kind of orbit should it have? 2) Could the same starshade be used by two different space telescopes, or does the ...
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0answers
55 views

How do I soundproof a Meade ETX-90 telescope?

I'd like to start using my Meade ETX-90 this summer in my backyard, but I'm worried that my neighbors will start complaining due to high noise this telescope makes when operating. How do I soundproof ...
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21 views

What are the up- and downsides of spherical and parabolic mirrors in telescopes?

What are the up- and downsides of spherical and parabolic mirrors in telescopes? I was able to find small bits of information from the web but not a good comparison. Assume the telescope is a ...