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6 votes
2 answers
332 views

Do we know at which angle the Event Horizon Telescope will look at the accretion disk of Sagittarius A*?

1 vote
1 answer
48 views

Can the Celestron Powerseeker 127EQ observe the moon during day time?

3 votes
2 answers
77 views

Focus Problems when using Barlow 3x or 4mm lens

4 votes
2 answers
389 views

Why are photos from telescope stretched at their edges?

1 vote
0 answers
42 views

Why does my 10mm eyepiece produce blurry images?

9 votes
2 answers
3k views

Why aren't reflector telescopes built with an offset secondary mirror?

4 votes
1 answer
158 views

General process of calculating what a telescope's diffraction spikes would look like?

0 votes
1 answer
181 views

How to make a 65 cm lens with a 20 cm hole in it for a Hamiltonian telescope?

1 vote
0 answers
22 views

uvotdetect sometimes doesn't make valid .fits files for DS9 to read (Swift UVOT, Heasoft)

3 votes
3 answers
327 views

How to choose eyepieces and other accessories for a Celestron 70mm f/5.7 portable refractor?

2 votes
0 answers
50 views

Metric to estimate measuring accuracy

1 vote
1 answer
135 views

How far can the best telescope see in outer space from Earth?

9 votes
1 answer
211 views

How to determine the scale on astronomical images?

6 votes
2 answers
138 views

JWST mirrors each can be "positioned in tip, tilt, piston, horizontal & vertical decentering and clocking". What does this mean?

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