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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Moon's equation of the centre discrepancy
According to the Wikipedia Lunar Theory article, the first term of the Moon's equation of the centre is
$$22,639^{\prime\prime}\sin l,$$where $l$ is the Moon's mean anomaly. According to the Wikipedia ...
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How does the Moon look like from different latitudes of the Earth?
I have heard, that on the northern hemisphere, you can estimate a direction of south if you imagine a line going through the tips of the border between illuminated and shadowed part of the Moon, and ...
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How does the moon pattern cycle through the 4 or 8 extremely visible phases, in terms of integer days?
I have never really thought about it, and this is more of a "thinking about how the ancient hunter gatherers thought about the moon and stars before civilization" sort of thought process, ...
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How do I calculate moon phase orientation at any Coordinates given all the necessary data?
I'm having a problem for a couple of days where I'm trying to accurately calculate the phase angle of the moon at any given Coordinates (lon,lat).If I know my current Coordinates, Moon and sun ...
CommunityBot
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The presence of maars on the Moon
Wondering if there's any evidence to date of the existence of maar craters on the Moon? If not, how probable is it that the moon ever supported the necessary conditions for maars to form?
A report ...
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Can I measure the moon's gravity?
Since I learned about Newton's gravity law, I wonder if I can measure the moon's gravity using (almost) no special equipment. The best I could come up with is a pendulum, which is in a resting ...
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What caused the “rake marks” in moon photos?
A conspiracy theorist on Facebook claimed photos from the moon show “rake marks” in the lunar soil. You have to zoom in and look very hard, but I do see a faint pattern of light-colored lines going ...
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What is the most stable orbit around the moon?
Let’s say I wanted to build a space habitat in orbit around the moon. Better still, let’s say I want to build a ring of habitats occupying the same orbital path, encircling Luna, to oversee the mining/...
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Can the motion of the phenomena of supermoons be modelled by an harmonic wavefunction?
Supermoons happen about 14 months...Can we consider the oscillating motion of the moon giving supermoons a simple harmonic wave? If so, what would be its wavelength?
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How do times of lunar standstills vary over time? If we folded them back into a lunar month plot, would they have "prograde and retrograde motion"?
The recent question Are lunar phases and lunar standstills in sync with each other? brought me to a standstill because I don't fully know what a lunar standstill is. It's one of those words like "...
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What's the difference between perigean spring tide and proxigean spring tide? [closed]
Also, is proxigean spring tide a special case of perigean spring tide
?
Are there other kinds of tides other than spring, neap, proxigean
spring, and perigean spring tide ?
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Determining the distance to the Moon from parallax using the following information
How could I determine the distance from the Earth to the moon by using the method of simultaneous parallax? I know the right ascension and declination as seen from two different points on earth. I ...
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How to get the right ascension of the Moon?
Is there any approximate way to calculate the right ascension of the Moon? I already got declination but still, need the right ascension to calculate the final position of the moon. Thanks for all ...
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How exactly is defined elevation on the Moon?
In a recent image by Pavel Gabzdyl, the highest (+10.7 km) and lowest (-9 km) points on the Moon are marked.
Detailed info about these extremal points can be found at the following links:
Highest ...
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Connection between Earth, Moon, Theia, and asteroid belt?
Are there other fragments aside from the Moon that resulted from the collision of Earth and "Theia" (as it's called in recent main-stream press stories)? And if not, why not? And what ...
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During night on the Moon is there Earth light and Earth phases?
I realise that night time on the Moon is two weeks, however I am curious if during the night there, whether or not the Earth reflects light in similar manner to the Moon.
On the one hand, I know it ...
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From a given latitude on Earth, how to calculate the number of days in a year when the moon is lit on the bottom?
From a given latitude on Earth, is it possible to calculate the number of days in a year when there is a wet moon , that is when the moon is lit on the bottom?
If, for example, I want to do the ...
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Python Program for Synodic months
I am trying to make an astronomical program for celestial bodies in our solar system (and beyond!).
However I want it to show how many Synodic months since New moon. Example: Since last 2022 there ...
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The exact definition of lunar eclipse
I was finding the definition of the lunar eclipse (in which the earth blocks the sunlight that comes to the moon), and I have found that it could be defined differently.
Definitions of lunar eclipse ...
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What does Ptolemy mean by "a line drawn from the centre of the earth through the centre of the moon to a point on the ecliptic"
This is from a translation of Ptolemy's Almagest:
Hence it necessarily follows that the straight line drawn from the
centre of the earth (which is the centre of the ecliptic) through the
centre of ...
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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 ...
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How long before two sidereal months start on the same lunar phase?
I was reading about the difference between the sidereal and synodic month when I started to wonder how many sidereal months need to pass before you get two that start on the same part of the synodic ...
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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 ...
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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 ...
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How long was a lunar month in ancient times?
As the Moon is getting farther and farther from Earth, it's natural that the time it takes to circle around our planet is going to increase, thus the month will be longer.
However, I read that the ...
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Moon's unusual gravity
We know that the Moon's gravity is about one-sixth that of Earth. Then I recently read that the mass of the Moon is about one-eightieth the mass of Earth. Since gravity depends on the mass of the 2 ...
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Why do I see rainbows around the moon?
Regularly, I see rainbows around the moon. Here is approximately what I see:
Right at the edge of the moon, I see a bright blue ring of light. Further out, I see an inner rainbow. This is not as ...
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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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Are these parallel lines I'm seeing in this image a real pattern on the Moon?
In this question I mention the GIF in EarthSky.org's Moon Phases update Lengths of lunar months in 2017. After watching it a while, I've noticed a pattern of parallel nearly vertical lines on the Moon ...
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Sun and moon's orbit in ecliptic coordinates using skyfield
I am new to using skyfield, is there any doc or help file that can show me on how to get the orbit of Sun and moon in ecliptic coordinate for a particular date and ...
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New moon rise same spot on horizon as sunrise, almost same time [closed]
I witnessed the new moon rise just ahead of a sunrise at the very same spot on the horizon. How often could I plan on looking for that occurrence again?
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Jean Meeus - calculating moon rise, transit and set times - help isolating error in logic
I've been working my way through the Jean Meeus Astronomical Algorithms book for a few weeks, to implement some of the key algorithms for a personal project. This task has been a little more complex ...
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How dark is the side of the Moon facing away from the Sun? ( I don't mean the far side)
Remember, the actual "dark side" of the Moon is not the far side, facing away from us that we can't see, but rather it's the side that faces away from the Sun that is illuminating it.
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Trying to understand lunar phases
Complete novice here. I'm trying to understand what appears to be two approaches to quantifying lunar phases. Have I got this right?
Named lunar phases can be understood as the Moon's ecliptic ...
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Are lunar phases and lunar standstills in sync with each other?
Do either of the standstills (N/S) coincide with full/new moon?
If yes - what is the relationship?
If no - what factors impact the relationship between the two?
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What experiments can be performed during a solar and lunar eclipse respectively?
As an amateur astronomer, I intend to perform a few simple experiments during total solar and lunar eclipses. However, I am not aware of all the parameters that can change during these eclipses and ...
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How can I compute the shape and orientation of the crescent for a given time and geographic location using data from the JPL Horizons?
I can compute the following data for the Moon for a given time and geographic location using the JPL Horizons system:
Apparent RA & DEC
Apparent azimuth & elevation (AZ-EL)
Target range & ...
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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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Is there a timekeeping word for the orbit of a moon?
For a planet, we can colloquially refer to its period of rotation as a "day" and its period of revolution around its parent star as a "year." Some worlds have unique terms, such as Martian days being ...
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JPL Ephemeris or Skyfield - how to get moon phase percentage (not illumination percentage)
I know how to use JPL's Horizons to get moon illumination percentage but I noticed that even at new moon, the illumination never goes to zero:
...
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Why doesn't lunar perigee always occur in the same lunar phase?
If the phases of the moon and the moon's perigee are just dependent on the point that the moon is in through it's orbit, why can perigee happen at different phases of the moon?
My thinking is this:
...
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tool to calculate moonrise/moonset and moon phase for any date for any location
I have googled for such a solution but I have not found anything substantial: I found one website but it was someone's side hobby so my confidence in it is low.
Thankfully, I have discovered ...
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Help me better understand how the plane of Moon's orbit around Earth behaves
Is the plane in which Moon orbits around earth, inclined with respect to earth's equatorial plane? If yes, is it constant or does it change with time? If it changes, how much time does it take to make ...
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Moon's rotation and revolution
Since the moon's period of rotation around its own axis, and that of its revolution around earth is (almost) same, we always see only one side of moon. This is what was, & is taught in schools. ...
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Tidal locking of Moon [duplicate]
Since our Moon is tidally locked with earth, we always see only one side of the Moon. In such a case, how and when did mankind first realize that the Moon is also revolving around its own axis? or for ...
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Is the Moon only 60x60 pixels?
In doing research on vision, I have learned that "20/20" vision corresponds to a visual acuity of being able to resolve details 1 arcminute in size, that most people have around 20/15 vision,...
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Bolometric correction of the full moon
Now I am solving the problem about the transition from $V$ (= -13 in 400-700nm) to $m_{Bol}$.
V is the full moon's apparent magnitude in 400-700mm(i.e., visible light), and $m_{bol}$ is the bolometric ...
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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 ...
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Why is the moon tidally locked with the earth?
Why the moon is tidally locked with the earth? What is the reason for the tidal locking of the moon with the earth? What causes tidal locking?
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Lunar Librations and Subsolar Point in Matlab
So I have been trying to write a program to generate the latitude and longitude of the lunar subsolar point in Matlab.
I have the ephemeris data from aero toolbox, but I can't seem to get values that ...
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