Astronomy Stack Exchange
Astronomy Stack Exchange

Questions tagged [the-moon]

Questions regarding Earth's only natural satellite. For questions about the natural satellites of other planets, use the tag [natural-satellite].

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Can the moon appear to be in any position in the sky?

It seems to me that the Moon has appeared in many locations - apparent locations - in the 'dome of the sky'. I know that the Sun follows an arc from east to west and that the arc is smaller in winter than in summer. Therefore the Sun cannot appear…
Donagh McCarthy
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Is it a coincidence that on the far side of the moon almost no seas are visible?

Sorry for the maybe too large pictures. They do make the surface structures of both sides of the moon visible though. Is it just a coincidence that on the side facing us is so much sea is visible? It looks as if on the far side more meteorites have…
Deschele Schilder
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Is it possible to completely see the edge of a half moon at night?

Some days ago, about 1 ~ 1.5 hours after the sunset I could see a very bright half moon, and the interesting part is, I think I could see the edge of the dark half of the moon, i.e. a whole circle, but with very little contrast to the surrounding…
bgusach
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Why does the Moon stablize Earth's axis?

In an academic study titled 'The Moon and the Origin of Life on Earth' it is said that 'If the Moon did not exist, the orientation of the Earth’s axis would not be stable, and would be subject to large chaotic variations over the ages. The…
Kyriakos Kyritsis
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Why doesn't the Moon, like the Sun, turn bright red when it's close to the horizon?

Why does the Moon, being close to the horizon, turn red only slightly, or not at all? Aren't the causes that lead to the coloring of the Sun (atmospheric refraction) are also true for the Moon? In addition, the spectrum of moonlight is more…
Vladimir Orlov
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How do we know the moon is smaller than Earth?

The moon is smaller than the Earth, but how do we know that (without the use of modern technology)? To be more specific, how can we show that the moon is smaller than the Earth (smaller diameter) with technology before 1800s?
Obama2020
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Why can we sometimes see the moon during the day?

At some points in the year, the moon at my location can be clearly visible during the day. Why is this? If it is any help, I live in Alberta, Canada.
aman207
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How can an area be on the day side 90% of the time?

In the magazine "Ciel & Espace", it is stated that crater ridge next to Shackleton crater is an interesting landing site for future missions because it is lit up 90% of the time. I get how an area can be in the shade 90% of the time, but how can an…
usernumber
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Why is the Earth-Moon distance not the same at each perigee/apogee?

I wonder why the Earth-Moon distance is not the same at each perigee/apogee. Isn't the Moon's orbit a fixed ellipse with Earth at one of the foci? If it is so, shouldn't the distance at perigee/apogee be a fixed value?
Michael Teoh
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How can I calculate moon phase and height?

How could I know what phase the moon is in when it's high in the sky during sunrise? How could I tell in general what its height in the sky will be at any given time?
JekylHyde
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During an eclipse, does the size of the moon and sun match perfectly?

During a lunar or solar eclipse, from our perspective when we look towards the moon and the sun is behind the moon, does it fit exactly? Has anyone calculated the sizes of each in a relative context? Obviously the sun is thousands of times…
public static
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Proportion of Lunar Fraction in a Year

I grabbed a year of lunar fraction data from the USNO and binned the counts to find the shape of the curve as below My understanding of lunar fraction was that 0.5 does not distinguish between the direction as it is a cycle from 0 (new moon) to 1…
Zac Warham
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The moon in the first phase visible in the sky is tilted

I never noticed it before that moon I see in the sky is tilted. Does the tilt of the moon in the sky indicate the direction of the Earth's axis and direction of Earth's rotation around the sun?
Wojciech Domalewski
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Satellite in orbit in front of and behind the Moon

Would it be possible to put a satellite into the same orbit as the Moon, but far enough ahead or behind the Moon to remain in place? Has this ever been done in practice?
Bingohank
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Is the moon's orbit circularizing? Why does tidal heating circularize orbits?

The moon has an elliptical orbit (of course), but as it inches away from the Earth each year, does its orbit become more circular and how come? Io's orbit is becoming more circular due to tidal heating effects, but why?
StellarExile
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