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4 votes
1 answer
311 views

What is the longest time the Moon can stay in the sky?

It is known that in northern latitudes the Moon, like the sun, can remain in the sky for a long time, a week or more. What is the longest time the Moon can stay in the sky?
Vladimir Orlov's user avatar
1 vote
0 answers
55 views

Has anyone attributed a specific Baily's bead to a specific feature on the Moon? If so, when was this first done?

From Wikipedia's Baily's beads: Lunar topography has considerable relief because of the presence of mountains, craters, valleys and other topographical features. The irregularities of the lunar limb ...
uhoh's user avatar
  • 30.7k
1 vote
1 answer
162 views

sideways crescent moon but also no moon somewhere else?

I live in Sumter, South Carolina and the moon looked like a crescent moon but sideways like a bowl. But when I told my friend to look at the moon they couldn't find it and they live in Buffalo, New ...
Cakebandit06's user avatar
3 votes
1 answer
115 views

Metonic cycle observation & display [closed]

I'm unable to locate physical display observatories for the 19 year Metonic cycle. How do I display this information & calendar detail on a concrete floor near the tropic of cancer? I seek a floor ...
Eric Snow's user avatar
4 votes
0 answers
621 views

How to measure the latitude of the moon?

In the geocentric solar ecliptic (GSE) system of coordinates, the position of the Moon is described by its longitude and latitude. The former is, with great accuracy, the angular distance between the ...
WordP's user avatar
  • 141
16 votes
2 answers
8k views

How does the earth cast straight and reversed shadows on the moon?

When the Earth regularly casts a shadow on the moon, why does the shadow progress from circular to a straight line and then to a reversed circle? Since the earth is a sphere, shouldn't it cast round ...
chowder's user avatar
  • 502
16 votes
3 answers
2k views

Was lunar libration first observed or first predicted? In either case, who was the responsible party?

How old is the idea of the far side of the Moon? got me thinking that as soon as we see the moon librate we have to come to terms with there being even more of it we can't see. The Moon's libration is ...
uhoh's user avatar
  • 30.7k
6 votes
1 answer
701 views

Would people on opposite sides of the earth see different details of the moon, if so are there actual photos demonstrating this?

I am aware of phases and the fact that opposite sides will see the moon flipped relative to the other but what I’m asking specifically is would the almost 8000 mile difference between the two ...
Beans's user avatar
  • 551
16 votes
5 answers
34k views

Why can I see sometimes a horizontal half moon instead of a vertical one?

Why do I sometimes see a horizontal half moon, instead of the more usual vertical one? I keep getting answers for crescent moons, but this is a half moon with its curve closer to the horizon, like a ...
Evilin Garnett's user avatar
2 votes
0 answers
30 views

Which is a better way to increase magnification - by choosing an eyepiece of lesser focal length or by choosing a telescope with higher focal length? [duplicate]

Magnification of a telescope = (focal length of telescope / focal length of the eyepiece being used) $$M=\frac{f_{objective}}{f_{eyepiece}}$$ If I want 75 X magnification and the following are the two ...
Pushkar Chaudhari's user avatar
1 vote
2 answers
145 views

First visibility of the moon

I am new here, and hope to state the question well. In Islam, it's known that the Lunar Month starts if the Moon is sighted after the sunset of the 29th day of that month. If someone claimed that ...
Muath Karaki's user avatar
3 votes
1 answer
170 views

Did NASA/JPL get "waning" and "waxing" backwards in this video?

The NASA JPL video What's Up: September 2019 Skywatching Tips from NASA says (per both the closed captions and audio): We’re in a several-month period right now when the new Moon falls right around ...
uhoh's user avatar
  • 30.7k
15 votes
2 answers
4k views

Is it possible to do moon sighting in advance for 5 years with 100% accuracy? [duplicate]

It is Ramzan and the usual heated disagreements between clerics here in Pakistan as to the sighting of the crescent. This time the minister of Science and Technology (who is not a scientist himself ...
Bibrak's user avatar
  • 259
3 votes
1 answer
144 views

Moon's path as seen from Earth

As observed from the surface of Earth: Will the moon ever repeat the same path (trajectory)? If yes, what is the period of repetition? And also will the moon cover the night sky with its path ...
Prabhanjan Naib's user avatar
3 votes
2 answers
3k views

How to calculate exact angle to the moon?

I am building some device as a gift for my girlfriend. For this device to work, I need to be able to calculate the angle to which I should look towards (3D angle), in order to see the moon. This ...
Gulzar's user avatar
  • 133
3 votes
1 answer
256 views

Recognising lunar month only by looking at the sky

Suppose somebody went on an island and don't have sense about time, dates, months. The only thing he has is seeing the sky. Is it possible to recognise which lunar month it is by just looking the sky? ...
Alem's user avatar
  • 139
2 votes
1 answer
2k views

How to know when the moon is visible on a particular night?

I am looking for beginners information on how I can know when the Moon is going to be visible on a particular night ? Google-fu says to look for moonrise information about my city from websites such ...
happybuddha's user avatar
9 votes
3 answers
16k views

Why haven't I seen the Moon?

It has been some time since I've seen the Moon. What are the conditions that might affect whether or not the Moon is visible within a 24-hour period? Please take into consideration any notable ...
Andrew lloyd's user avatar
3 votes
4 answers
8k views

What is the first recorded reference to the Moon being a satellite of the Earth?

I saw a list recently of the moons of the various planets and the discoverer(s) and date of discovery. Earth's Moon was listed as Unknown. I know you don't 'discover' a huge disc in the sky. But ...
user avatar
5 votes
1 answer
4k views

Can you see city lights on the Moon from Earth?

This is the opposite of another question. That question is about whether you could see cities on Earth if you were standing on the Moon. Let's there are cities on the Moon and you're standing on the ...
RichS's user avatar
  • 772
7 votes
2 answers
552 views

Was that actually a shooting star during the supermoon eclipse on September 27th 2015?

During the super-moon total lunar eclipse on September 27th a meteor-like streak passed very close within view of the event. It appeared to happen at the very middle, the maximum eclipse. [...
R. Carbone's user avatar
2 votes
0 answers
109 views

Illusion of a lunar eclipse [closed]

A little over half a year ago, I think it was mid March 2015, I glanced out of my window at about 4 am, to see what appeared to be a very bright total lunar eclipse, as in, the moon was full and ...
GRS's user avatar
  • 21
2 votes
3 answers
10k views

Why does the moon appear on cloudy night sky?

Now, I was looking the sky when I saw the Moon showing up in a sky completely cloudy, like this: But a little different. The clouds were doing an eye shape. What does explain that phenomenon? Looks ...
Shinomoto Asakura's user avatar
3 votes
0 answers
109 views

How do I deduce my latitude and longitude from N obervations of occultations from the same place?

I think it would be an interesting exercise to measure the latiude and longitude of my house using N occultation timings. I would like to see how precisely I can measure it using that technique, and ...
John's user avatar
  • 355
11 votes
1 answer
13k views

Can an amateur astronomer bounce a laser off the moon?

In the TV show "Big Bang Theory" episode "The Lunar Excitation", the gang fires a laser from their rooftop, bounces it off mirrors on the moon, and measures the laser coming back on a computer. Is ...
Reactgular's user avatar
9 votes
3 answers
6k views

How to calculate the altitude of the Moon?

With the known latitude coordinate of the observing position, how to find the altitude of the moon when it is high, i.e when it crosses the local meridian?
Ken's user avatar
  • 366