Linked Questions

21 votes
4 answers
3k views

Can you see something active in the sky apart from satellites? Can there be amateur time-domain astronomy?

What I mean is an event unfolding that is viewable by naked eye or telescopes, and doesn't take comparing days of footage to see moving pixels. Apart from satellites, is there something that moves or ...
Firsh - justifiedgrid.com's user avatar
17 votes
3 answers
3k views

How often are there lunar eclipses on Jupiter

For the Earth-Moon system, the orbit of the Moon is at a slight incline compared to the plane of the ecliptic. This incline is enough for there to be eclipses roughly twice a year rather than every ...
usernumber's user avatar
  • 17.6k
9 votes
4 answers
5k views

Planets looks like normal stars when I see them using telescope

I've been trying to see planets using my 114 mm (aperture) f=900 mm telescope. For the moon, I got very good quality pictures, but when I try to see planets they just appear to be as if I'm looking at ...
Kamal Aujla's user avatar
15 votes
2 answers
2k views

During solar eclipses on Jupiter, can the moon(s)' shadow(s) on the surface be seen from Earth with a telescope?

All of the Galilean moons are large and close enough to Jupiter that they can completely eclipse the sun and allow a solar eclipse to happen. My question is can an observer from Earth, see the moon(s)...
user177107's user avatar
  • 2,699
9 votes
2 answers
3k views

How does an eclipse differ from an occultation?

A comment in response to this question suggests that an eclipse differs from an occultation in that the former casts a shadow while the latter doesn't. This isn't particularly satisfactory since ...
CatchAsCatchCan's user avatar
7 votes
1 answer
1k views

Why does Callisto only have eclipses every 3 years?

I don’t understand why Jupiter only eclipses Callisto in three year periods separated by three years. I get that the reason Callisto doesn’t always have eclipses is because of the combo of Jupiter’s ...
Elhammo's user avatar
  • 1,107
2 votes
1 answer
2k views

Which eyepiece should I use to view planets with a Slokey Skyways 50080 telescope?

I am new to Astronomy. My husband bought a Skyways 50080 for me for my birthday. It's an f=500mm refractor made by Slokey. The 80mm aperture makes it a fast f/6.25. It came with three eyepieces; 25, ...
Kate's user avatar
  • 29
3 votes
1 answer
302 views

How to test accuracy of DE441?

I want to write about processing DE441 data for Moon and Sun and include a section about the validation and accuracy testing of the algorithm. Is there a website where I can retrieve documentation for ...
Ath Genube's user avatar
3 votes
1 answer
314 views

What I can observe with a 80/900 refractor telescope? What can I study?

Recently I bought a telescope after a very good conversation with an astronomer friend of mine. The main goal is to see planets. However, Mars is so difficult and is far to find it in opposition. I ...
Linnc's user avatar
  • 155
3 votes
1 answer
355 views

Eclipses of Jupiter's Moon during Retrograde motion

When Jupiter is undergoing retrograde motion as seen from the Earth, would you expect the eclipses of Jupiter’s moons to occur several minutes early, several minutes late, or neither? Can someone ...
Boring Loop's user avatar
1 vote
1 answer
101 views

How does the Large Binocular Telescope resolve so well in both orthogonal directions simultaneously?

The Forbes article Ask Ethan: How Does Very-Long-Baseline Interferometry Allow Us To Image A Black Hole? includes an example of optical interferometry from the Large Binocular Telescope, shown below. ...
uhoh's user avatar
  • 30.6k
1 vote
1 answer
101 views

A night caused by an eclipse

Is there a term or a name for the darkness caused when a planet eclipses its moon? For example; if people lived on Titan, a small portion of the near sides lunar day would be eclipsed or partially ...
Erik Strife's user avatar