The moon tag has no wiki summary.
22
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4answers
2k views
Why is a new moon not the same as a solar eclipse?
Forgive the elementary nature of this question:
Because a new moon occurs when the moon is positioned between the earth and sun, doesn't this also mean that somewhere on the Earth, a solar eclipse ...
16
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8answers
13k 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?
16
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6answers
676 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.)
15
votes
2answers
112 views
What is a “Trojan Moon”?
Today I read an article about Saturn's moon Helene, and it was described as a "Trojan Moon" but no further explanation was given. It was difficult to even get any context about the term from the ...
15
votes
1answer
627 views
How can the Moon have such a strong effect on the ocean?
The gravitational acceleration on Earth is approximately $ 10 \mathrm{m}/\mathrm{s}^2 $. Compared to this, the tidal effect of the Moon's gravity gives a local variation in the acceleration of ...
15
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3answers
452 views
Does the Moon's core still contain significant heat?
On earth, using earth-sheltering techniques can significantly reduce the temperature fluctuations on a structure. Would the same statement be true as well on the Moon? Does the Moon's core still ...
13
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5answers
2k views
Why do we always see the same side of the Moon?
I am puzzled why we always see the same side of the Moon even though it is rotating around its own axis apart from revolving around the earth. Shouldn't this only be possible if the Moon is not ...
12
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3answers
13k 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 ...
12
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1answer
162 views
Impact location that created the moon
I was reading an article today about the 1000th orbit of the Lunar Reconnaissance Orbiter, and as many of you know NASA created an animation that simulates the history of the moon. It is speculated ...
11
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0answers
288 views
Strange things about new moon [duplicate]
I have some strange and infantile questions about new moon. I want to know how is it possible that the Moon is not visible at night and also at day it is not Sun eclipse?
I will explain the problem in ...
10
votes
1answer
535 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?
10
votes
1answer
37 views
Why did the june 2011 lunar eclipse last so long?
It was kind of hard to miss the lunar eclipse this week, although I didn't see it in person (Sod's law means that on every relatively major astronomical event clouds cover where I am). From what I ...
10
votes
2answers
397 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 ...
10
votes
1answer
134 views
How long will our artifacts last in moon & space?
Given all the different space probes and equipment that have been either launched into space or lying on the moon. How long will they last before they get decayed into dust or some unrecognizable ...
10
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0answers
475 views
Why does the moon look bigger at the horizon? [duplicate]
Possible Duplicate:
Why does the moon sometimes appear giant and a orange red color near the horizon?
Why does the moon look bigger at horizon or skyline than at other times e.g. at ...
9
votes
3answers
11k views
The Moon during the day
Why do we see the Moon during the day only on certain days and not every day?
9
votes
2answers
130 views
Where does the dust on the moon come from?
From the Apollo missions we know that the moon is covered with dust. Where does it come from? Is it from the erosion of the moon rock? By what? Or by accretion of dust from space? Which comes from ...
9
votes
1answer
273 views
Apollo and orbital mechanics: orbital decay if the Trans Earth Injection (TEI) burn had failed
I'm reading Jim Lovell (Apollo 8 and 13) and Jeffrey Kluger's book Apollo 13, which is a fantastic read about a long past era I only have kindergarten memories of. On page 54 there is a paragraph that ...
8
votes
4answers
254 views
Can a moon have another large body as a satellite, and are there any examples of such?
In my mind, I'm comparing it to the Sun-Earth-Moon system. After all, the Earth is primarily a satellite of the Sun, but the Moon is still gravitationally bound to the Earth. Could something like this ...
8
votes
3answers
698 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 ...
8
votes
1answer
242 views
What causes a ring-like image around light of the moon?
I just encountered an interesting image in sky.
As you can see in following images there was a ring-like image around light of the moon.
I don't know if it was clouds but it was looking like it is far ...
8
votes
2answers
949 views
How does the central peak in moon craters form?
The central peak in many of the moon's large craters are visible with a telescope and they seem a little odd to me. Can someone explain how they form.
8
votes
1answer
187 views
How to explain the Moon halo phenomenon?
Today, here in Brazil, I have observed (and is still observing) an interesting phenomenon.
The Moon is near to a big star in the sky, but this is normal. The interesting part is what's around them.
...
8
votes
1answer
148 views
Could the earth have another moon?
First, to clarify: I'm not asking if perhaps there's a moon that we haven't found yet. The question is, theoretically, would the earth be able to have another stable moon in addition to the current ...
8
votes
5answers
198 views
sun-moon-earth anomaly
When one looks at the sun and the moon in the sky together, why is it that the illuminated crescent of the moon does NOT "point" at the sun?
(More correctly the perpendicular bisector of the straight ...
7
votes
2answers
203 views
Why don't we see solar and lunar eclipses often?
Since we see the new moon at least once in a month when the Moon gets in between of the Sun and the Moon at the night and as far as I know if this happens during the day, you'll get to see a solar ...
7
votes
2answers
63 views
What distinguishes a moon from orbiting space debris? Or in other words, when is a satellite “too small” to be a moon?
The Wikipedia article on Natural Satellites doesn't really give an adequate distinction as to what distinguishes a moon from other orbiting bodies. What I am looking for is a classification that ...
7
votes
1answer
308 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?
7
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2answers
528 views
How can the date of lunar eclipses be calculated by hand?
How can the date of lunar eclipses be calculated? Especially without the aid of a computer.
7
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2answers
33 views
Where to find Lunar Eclipse data
I am wondering whether there's a good resource to find data about upcoming Lunar Eclipses.
For example, showing the percentage of the eclipse over time. Such as: 17:23 GMT - 0%, 17:40 GMT - 10%, etc.
...
7
votes
1answer
70 views
Polar ice deposits on the Moon - dispersed in permafrost loose rubble, or also massive/layered?
Water has been discovered on the Moon with remote sensing methods. Read the press release Diviner results indicate presence of widespread ice on the Moon on the "Diviner" infrared instrument on the ...
6
votes
2answers
36 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 ...
6
votes
1answer
564 views
What happened to Apollo's Saturn-third-stage rockets?
I read recently the original Apollo 11 press release and it mentions that the Saturn V's third stage (used for Trans-Lunar Injection) was deployed into a solar orbit of some kind:
I know that on ...
6
votes
2answers
225 views
Is it possible that I just saw Jupiter's moons?
Today at about 18:00 I was looking for Venus near the moon and I saw a short bright line. I thought that maybe I was seeing Venus' crescent but it was perpendicular to the crescent of the moon. I then ...
5
votes
3answers
297 views
Why is Titan able to maintain an atmosphere, and not Luna?
I just read stability of hypothetical lunar atmosphere. From the correct answer, i understand, the low escape velocity from Luna is part of the reason it is unable to retain an atmosphere.
Titan ...
5
votes
2answers
107 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, ...
5
votes
1answer
6k views
Is the moon a planet?
Can our moon qualify as a planet? With regard or without regard to the exact definition of the planet, can the moon be considered as planet as Mercury, Venus and Earth etc. not as the satellite of the ...
5
votes
2answers
107 views
Io - Turned inside out
In a lot of the descriptions of the moon Io it frequently states that the moon, because of volcanic activity, has been literally "Turned inside out". What exactly is meant by "Turned inside out" and ...
5
votes
1answer
42 views
Best observing techniques for a Total Lunar Eclipse?
Is there any good tricks to observing a total lunar eclipse that I should be aware of? Just wanting to know what to do to be prepared for the upcoming one, but please post in general for future ...
5
votes
1answer
52 views
Shadow of a Jovian moon over the Great Red Spot
Where can I find pictures of the shadow of any of the Jovian moons partially covering the Great Red Spot?
A series of such pictures over time would even be better. The idea is to learn more about the ...
5
votes
3answers
340 views
Why does the moon appear bigger close to the horizon, rising or setting? [duplicate]
Possible Duplicate:
Why does the moon sometimes appear giant and a orange red color near the horizon?
I made a little research about this and found this article ...
5
votes
1answer
226 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 ...
4
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2answers
117 views
If the moon was rapid enough would it be able to orbit the earth from a close distance?
If the moon was close in orbit that it's surface was like 100 km away from the earth's surface. And it had a large enough angular velocity will it be able to hold orbit?
If this was possible, is ...
4
votes
1answer
188 views
If the Moon had gravity as good as the Earth and a magnetic field could it have supported life?
If the Moon had gravity as good as Earth and a magnetic field could it have supported life? Because if the Moon had gravity, it could have retained water more than is present today on the surface.
...
4
votes
2answers
213 views
Illumination calculations?
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.
I am ...
4
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2answers
183 views
What kind of cooling mechanism could be used in outer space?
This question arises out of this question on Quora -
Apollo 11: 1969 Moon Landing: Did Neil Armstrong really land on the moon?
I'm convinced with most of the explanations provided in the first ...
4
votes
3answers
36 views
How can one predict the length of the Synodic month? Why is it irregular?
I'd like to write a program that uses the exact (down to the second) amount of time from one new moon (or full moon) to the next.
Yet, I am told that this period is irregular.
Yet, it seems to be ...
4
votes
1answer
167 views
How to make a moondial?
A question came up on Outdoors StackExchange, How to tell time at night. I wrote an answer to that question, and in my answer I said that a standard sundial wouldn't work without some fiddling, but ...
4
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1answer
72 views
Does the Earth help stabilize changes in the moon's obliquity as well?
We know that the moon helps stabilize changes in Earth's obliquity.
But what about Earth and the moon? Are some of the obliquity-stabilizing effects (of the moon on the Earth) communicated through ...
4
votes
1answer
189 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 ...
