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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Conversion of Moon's Celestial Position (RA and dec) to Horizontal Coordinates [closed]
I'm currently attempting to calculate the equatorial sky position of the Moon for any given Geostatic position (longitude / latitude) for any given datetime.
I have tested my altitude and azimuth ...
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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 ...
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Apparent Magnitude of First quarter Moon [closed]
Given
Apparent magnitude of moon is -12.5.
Distance of moon and earth is 384400 km.
Diameter of Moon is 31 arcmin.
Phase of moon is 0.5.
Find the apparent magnitude of first quarter moon.
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Is there a precise definition of "Supermoon"?
Elsewhere online I keep reading that a supermoon is the situation when full moon coincides with moon perigee. But see this plot from wikipedia Lunar Distance entry
The perigee distance varies wildly ...
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Can we see the south Pole of the Moon standing on North Pole of the Earth
As the Moon's orbit is inclined to Earth's Equator and radius of earth is only 6350Km but Moon is 385000Km away, we should be able to see the south pole of the Moon from below- i.e standing on North ...
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If months are based on the moon, then why are the months longer in the Gregorian calendar than lunation?
What I have always thought / known is that:
Days are based on the period of rotation of the earth.
Months are based on the moon.
Year is the time taken by the earth to make one revolution around the ...
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Why does Earth have only one moon? [duplicate]
The moon was first formed billions of years ago when a Mars-sized object crashed into Earth. The pieces formed over time to create our moon. Why was only one moon formed? Could Earth have had other ...
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Using parallax to find distance to the moon
I want to use the parallax method (from scratch) to find the distance between the earth and the moon. To get a significant parallax, I need to choose a large baseline. I live in India and my friend in ...
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Moon cycles used for gardening & harvesting
I appreciate that this question may deviate from the standard astronomy questions.
I have recently read an article that suggest that gardeners, farmers & winemakers etc sometime use the moon's ...
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What did I photograph around 6 AM on April 27th, 2021? Supermoon plus comet?
Facing SW just before sunrise on April 27, 2021 in Central Florida:
The timestamps on the pics start at 6:23 end at 6:27. It was still visible and breaking up like a post launch trail that I would ...
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What is a "fundamental location", and why is Mosting A defined as one for the moon?
The crater Mosting A was chosen to be the "fundamental location" for the Moon's coordinate system (latitude and longitude). But what exactly is a "fundamental location"? What does ...
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What do these coordinates mean: MW - VP101 3° 12' 43.2'' S 5° 12' 39.6'' W?
I have a jacket with a tag that bears the label:
MW - VP101
3° 12' 43.2'' S
5° 12' 39.6'' W
When I looked it up, I discovered that these are the coordinates of the ...
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If you are standing on the shore and it is high tide, what are the two possible locations for the moon relative to where you are? [duplicate]
Science Class If you are standing on the shore and it is high tide,
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Are interstellar meteorites more common on the moon's polar regions?
Given that the rocks of the solar system mostly travel on the disc, is there any considerable probability that impacts on the moon coming straight up and down can be interstellar rocks?
If axis-...
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Lunisolar calendar: what phase was the moon Y years ago on the spring equinox? [closed]
How would I go around answering these questions (e.g., for $Y=10,000$ -- IOW, historical observations are not available and the time is too long ago to rely on a fixed calendar):
How many days ago ($...
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Lunar Inclination
Are there published tables for Lunar Inclination?
I am interested because I believe this determines the degree of "Diurnal Inequality" of tides. There are tons of publishes tables of tides ...
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Is it easier to see the young moon when it's closer to the sun?
With the naked eye, would it be easier to see the moon when it's close to the sun, because it might reflect some more light (or not, I'm not sure) or farther from the sun because the sun shines ...
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Why temperature of dark side of moon is not 3 Kelvin
The temperature of the space between Earth and the Moon is around 3 Kelvin ($\approx -270^\circ {\rm C}$). The moon has no atmosphere, therefore the heat convection is not possible from the bright ...
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How big and how far away would the moon be if earth was the size of Jupiter?
If the earth were the size of Jupiter, what would its 'moon' be in both relative size and distance? I did some quick figuring and think I roughly figured out that if placed at the position of the sun, ...
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Has lunar opposition surge ever been observed from Earth? From Earth orbit?
This thorough answer to How long does lunar opposition surge last? Are there measurements of the full Moon getting suddenly brighter? details observations of lunar opposition surge by the Clementine ...
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How long does lunar opposition surge last? Are there measurements of the full Moon getting suddenly brighter?
Wikipedia's opposition surge is a short article and forwards shadow hiding and coherent backscattering as proposed mechanisms, but it doesn't really explain how much the brightness of the Moon ...
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How to determine when Sun/Moon is aligned to two location on Earth's surface?
I would like to make a photo to Moon/Sun when it is very low on horizon, so if I make the shot far away from an object on Earth surface, it appears as big as the Sun.
But how can I calculate the right ...
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Where is the Moon for the last five or six days? [duplicate]
The date today is March 18th 2021 Thursday it's 6:00 p.m. I'm in the area of Sarasota-Bradenton Florida. I haven't seen the moon and it's been clear skies for roughly the last five or six nights... I ...
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If Planet Nine indeed exists, how large a impact event there should be to be seen from Earth?
Recently I've found this news article, A meteorite crashed into the Moon during total lunar eclipse in January, about a collision into the moon that happened while a lunar eclipse was under way. ...
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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 ...
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Absolute model ages of lunar craters
I have been looking at several articles on the dating methods of craters, but I am wondering how exactly the "absoluteness" creeps into it. I came across several methods that link crater &...
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This article says the moon may start moving closer to the Earth in the distant future; could this be true?
Bruce Dorminey wrote an article for Forbes with the title of "Earth And Moon May Be On Long-Term Collision Course". The article notes:
"For now, our anomalously large Moon is spinning ...
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What exactly was the Moon's "Evection Resonance"?
Ward et. al define the evection resonance of the Moon with the Earth and Sun as:
occurring when the lunar perigee precession period equals one year.
Does this simply mean that the angle formed by ...
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How can lunar pits be distinguished from craters?
ESA's news En route to exploring lunar caves features the following paragraph:
The Moon's surface is covered by millions of craters, but it also hosts hundreds of very steep-walled holes known as ...
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Elongated Moon crater statistics?
Many craters on Moon have circular shape as a result of the explosion upon impact. I got interested in oblong craters created by impacts striking the surface at a very low angle. Is there any ...
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Do the earth and the moon reflect the different fractions of total solar radiation proportionally?
Reading on this website that: "All of the energy from the Sun that reaches the Earth arrives as solar radiation". "Solar radiation includes visible light, ultraviolet light, infrared, ...
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How can the author of this article conclude that earth-shine on the moon is 100 times brighter than moon-shine on earth? [duplicate]
I don't understand the reasoning of the author of this article, on page 26. How can he conclude that full earth-shine on the moon is 100 times brighter than full moon-shine on earth?
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Accelerations on the Moon due to its orbit and its spin
A gyroscope is placed on the equator of the Moon. It detects among others 2 accelerations: one due to the orbit and one due to the spin. What is the module of the second one compared to the first one?
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Which unit is most suitable in comparing needed light intensity for night reading on the Moon, vs on Earth?
Which unit is best to use, and why, when determining how many times easier it is to read a newspaper (or any other printed text) on the moons surface at night under a full earth, compared with reading ...
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Solar wind, Earth wind and planetary winds?
In February 2021, a new form of "electrified gas breeze" was announced, see blog by Tony Phillips entitled A New Form of Space Weather: Earth Wind which might a possible explanation for ...
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Scholarly work on the gravitational disruption of a rocky planet by a close pass with another planet?
note: While the apparently abandoned question Effects of a rogue planet passing between the Earth and the Moon? (inspired by Thundarr the Barbarian) asks for speculation and was answered with it, this ...
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Did the Moon have a substantial atmosphere in the past?
The layer of gas surrounding the Moon is very thin. It is a surface bound exosphere, where particle-particle collisions are rare.
In the past, the Moon was more geologically active, with eruptions ...
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What replenishes the lunar atmosphere?
It is often said that the Moon doesn't have an atmosphere. But there is an envelope of gas surrounding the Moon, albeit a thin one, so the Moon has at least an exosphere.
The Moon doesn't have its own ...
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Can we see traces of exo-moon formation?
Our Moon was likely formed by the collision of a Mars-size object with the Earth soon after the planets first formed. Would traces of such an event be detectable by observing the protoplanetary disc ...
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Is oxygen really the most abundant element on the surface of the Moon?
I found this infographic that seems to say that oxygen is the most abundant element on the surface of the Moon. Is this really the case? If so, under what form is this oxygen?
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Does lack of atmosphere on the moon make earth-shine more, or less, bright?
The earth acts like a light-globe in the sky for half of the moon, the side that is facing the earth. In what way does lack of moon atmosphere influence earth-shine. Does it make earth-albedo brighter,...
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What is the degree of reflection of light from sun to the moon? [closed]
As Moon reflects the light from the sun it must have an ANGLE OF INCIDENCE and ANGLE OF REFLECTION...
What Is the angle of reflection then?
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How many times brighter would full-earth-shine appear to people standing on the moon, than full-moon-shine does to people on earth?
The definition of brightness, according to Wikipedia:
the term brightness in astronomy is generally used to refer to an object's apparent brightness: that is, how bright an object appears to an ...
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Why would the side of the moon that faces earth be as dark as the far side of the moon?
Somebody suggested that the side of the moon that always faces the earth is as dark as the far side of the moon, but is that really the case? Doesn’t earth-shine make the earth-facing side of the moon ...
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When was the last eruption on the Moon?
The lunar mare are basins that filled up with magma over the course of the Moon's history. So there were eruptions on the surface of the Moon at some point in time. When did the last eruption happen ...
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Moon's and nodes' inclination to the Invariable plane
Moon is inclined to the ecliptic 5.14 degrees. Earth's inclination to the invariable plane is 1.57869 degrees.
What is the Moon's, and node's inclination to the invariable plane?
Since the Moon has an ...
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Sunset moonrise what happens in between?
Here in south London I have just seen that the sun will set at 16:45 hrs but the moonrise does not happen until 2hrs later 18:45 hrs what is happening in this two hour void, will it be too dark to see?...
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The moon has just the right speed not to crash on the Earth or escape into space. What are the odds?
My understanding is that the moon was created a long time ago when Earth was hit by a big asteroid.
The debris then agglomerated into the Moon, which happens to be orbiting at the exact speed required ...
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On a lunar map, why is it labelled East on Earth, West on Moon?
source
Why is east and west reversed for the moon? Why does north and south remain the same?
Please explain like I'm five.
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How to calculate the period of a lunar mansion?
What is the period of a lunar mansion or station referring to and how is it calculated? Wikipedia says the following:
A lunar station, also called a lunar mansion or lunar house, is a segment of the ...
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