A smaller body orbiting a larger, primary body, where the primary body is not a star.

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2
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2answers
228 views

Why can't you see meteors, but you can see comets from the moon?

Why can't you see meteors from the moon and why can you see comets?
6
votes
2answers
158 views

In what ways can a lunar eclipse occur?

In what ways can a lunar eclipse occur? Also, on what percentage of the Earth are they usually viewable? I am aware that there are multiple configurations that constitute a lunar eclipse (umbral, ...
8
votes
3answers
2k views

Why are there more lunar maria on the near side than on the far side?

It is widely known that the side of the moon that faces us has a particularly large number of dark patches, which resemble seas of liquid, hence, "maria". It is strange, though, that the far side of ...
10
votes
2answers
2k views

Observing Jupiter's non-Galilean moons

What strength of telescope is required to observe some of the non-Galilean moons of Jupiter? My current telescope at 50 magnification resolves the Galilean moons well, but I'm guessing it's far ...
16
votes
3answers
59k views

Why does the moon sometimes appear giant and a orange red color near the horizon?

I've read various ideas about why the moon looks larger on the horizon. The most reasonable one in my opinion is that it is due to how our brain calculates (perceives) distance, with objects high ...
15
votes
1answer
1k views

When will the Moon reach escape velocity?

From what I know, the Moon is accelerating away from the Earth. Do we know when it will reach escape velocity? How do we calculate this?
8
votes
2answers
600 views

Is there any evidence for the claim that the moon was once part of the Earth?

There is a hypothesis that says a part of the Earth was split away and became the Moon. Is there any scientific evidence for this claim?
6
votes
2answers
42 views

Scientific value of timing total lunar occultations

Is there still scientific value in timing and reporting total lunar occultations? Why would I time total lunar occultations (grazing occultations are out of the question)? When I reported ...
20
votes
6answers
2k views

Can the apparent equal size of sun and moon be explained or is this a coincidence?

Is there a possible explanation for the apparent equal size of sun and moon or is this a coincidence? (An explanation can involve something like tide-lock effects or the anthropic principle.)
4
votes
1answer
228 views

The Orbiting Moon as a Quantum Object

How would the quantum mechanical treatment of the moon as a gravitationally-bound object differ from the usual treatment of the hydrogen atom using Schrödinger's equation? [The earth's gravitational ...
23
votes
8answers
36k views

Why doesn't the Moon fall upon Earth?

Why doesn't the Moon, or for that matter anything rotating another larger body, ever fall into the larger body?
5
votes
1answer
276 views

Determining Average Tidal Effects

Maximum tidal heights vary widely across the globe, from 16 m in the Bay of Fundy to mere centimeters elsewhere. These variations are due to coastline and shoreline differences. This makes it ...
1
vote
4answers
7k views

How does the moon reflect light?

We can see the moon in the night because it reflects sunlight. But the light is incident on the opposite side of moon with respect to the observer in the night. In this case, how does the moon ...
25
votes
8answers
16k views

Why CAN we see the new moon at night?

I understand that the Moon's phases are determined by its position in orbit relative to the Sun. (See: Full Story on the Moon). The "shadow" is not cast by the Earth (a common misconception - this is ...
4
votes
2answers
551 views

Calculating the illumination of the moon

I am trying to find a formula that will enable me to calculate the illumination of the moon down to one thousandth of a percent, given that the Gregorian year, month, day, and hour is known. Can ...