Questions tagged [moon]
A smaller body orbiting a larger, primary body, where the primary body is not a star.
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What does the sky look like from the moon?
From pictures taken on the moon, it appears that there are no stars visible in the sky, but I do not know if this is an effect due to cameras.
What is the actual appearance of the sky on the moon?
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Will the moon ever proceed to lose its orbit and hit the earth?
Assume that the moon it orbiting the earth in a circular trajectory.
It will experience an acceleration directed towards the centre of the earth given by $\frac{GM}{R^2}$ where $G$ is the universal ...
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Why does the Moon - which is grey - appear white to us even at daytime?
The color of the Moon as viewed more closely, is grey. But when we see it in the sky it appears white to us. Why?
Although this question has some answers here: Why is the surface of the Moon white? (...
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If comets are thought to brought water on Earth could there be water in form of ice on the neighbouring Moon's poles?
If comets are thought to brought water on Earth could there be water in form of ice on the neighbouring Moon's poles? As water can easly evaporate if there is no atmosphere as in the case of Moon's ...
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Why does water ice on the Moon not sublime?
I heard that water in form of ice was found on the Moon. Why would the ice not sublime (evaporate) due to low atmospheric pressure?
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Has anyone experimented with simulating moon lighting?
Has anyone (in general) experimented with simulating moon lighting?
It means the following. A gray ball is illuminated with light with a brightness equal to that of the sun.
And at the corresponding ...
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Calculating the Local Lunar Sky at a specific point in lunar coordinates?
How can one calculate the local sky observable from any given point on the Moon, expressed in lunar coordinates? Specifically, I would like to understand the methodology and equations involved in ...
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If the Moon suddenly got heavier/lighter, would it crash into/fly away from the Earth, or would it stabilize at a different orbit?
If the Moon became suddenly gained 20% of its mass, would it come crashing down to the Earth, or would it just stabilize at a lower orbit? Similarly, if it suddenly lost 20% of its mass, would it fly ...
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When the new moon will become visible - after how many hours of conjunction
The moon will be totally invisible during Conjunction of moon, sun and earth.
After how many hours of conjunction, moon will be visible from earth.
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On the tidal heating of a moon. What is the second Love number?
Years ago it was asked here how to calculate the tidal heating of a moon orbiting another body with a simple equation. The answer is very detailed. They explain the equation, its shortcomings, the ...
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What would be the period of a Foucault pendulum placed at the pole of the Moon?
How long does it take the Moon to rotate about itself once?
There are two answers to this, the sidereal period and the synodic period.
Sidereal period would be the quick answer to the question here, ...
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Which parts of the electromagnetic spectrum cannot be used for remote sensing of the Earth system and why? Is that different on the moon? Why?
Which parts of the electromagnetic spectrum cannot be used for remote sensing of the Earth system and why? Is that different on the moon and if yes, why?
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How to determine whether an atomic clock had "ticked at the Moon's natural pace"? (Nature 614, 13-14 (2023))
The recent news article "What time is it on the Moon? Researchers plan to build a lunar clock", Nature 614, 13-14 (2023) claims that
"Clocks on Earth and the Moon naturally tick at ...
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How exactly does the Moon stabilizes Earth axial tilt?
There are many references regarding the Moon stabilizing the tilt of the Earth's rotational axis. I'd like to see some support for that claim, more than non-sequitur handwaving "Moon causes tides,...
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The radius of Earth is 4 times the radius of the moon. Estimate the acceleration due to gravity on the surface of the moon [closed]
I have derived an expression here which just needs the ratio of the densities of the Earth and its moon. My question is how do I go about finding this ratio or is there another way to approach this ...
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High school thesis project about Jupiter's moon Europa [closed]
So basically, I have to write a thesis paper because I'm in the last year of high school. It is an independent research project and the culminating work of my studies in school, so it represents my ...
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Centre of Gravity of Earth-Moon Elevator [closed]
Suppose you have a cylindrical elevator that resembles a rod of mass $m$, cross-sectional area $A$ and uniform density $\rho$, with a length $L$ spanning the distance between the Earth and the Moon. ...
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Are moons always smaller than the planets they orbit?
I'm not a physicist, asking for knowledge. Is there any moon orbiting a planet, but bigger than that planet? If not, is it mathematically possible for a bigger object to orbit around a smaller object ...
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How much does the moon change in diameter as the gravity of the planets and sun act on it?
What is the maximum distortion of the moon? Is it measured in centimetres or metres or kilometres?
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Would Aeroplanes or Helicopters work on our Moon?
Would Aeroplanes or Helicopters work on our Moon?
In general , I think , in Aeroplane Case:
(1) Air is required for Aeroplanes to float : Would Moon have enough air?
(2) High speed is required for ...
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Why is the time difference of equal tide states not 50 minute if one lunar day is 24 hour and 50 minutes?
I do understand that tidal forces are caused by de difference of gravitational force between both opposite points of the earth where a bulge is formed.
I do understand that a lunar day is ruffle 24 ...
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What is the rate of change of the Moon's eccentricity?
So I know the Moon's current average eccentricity is ϵ≈0.039±0.006, but was this always the case? Was it ever increasing or decreasing, and if so is it known what the current rate of change is for it? ...
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If the Earth and the Moon were smaller, would moon tides be more or less intense?
If the Earth and Moon were smaller (and everything on them too, but keeping the same average density and the same "relative" distances, I mean... the same proportions!), would the tides ...
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Weightlessness in Artificial satelite and moon
Why don't astronauts feel weightlessness in moon while they do in artificial satelite orbiting the earth?
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Why is the Moon's gravity so high compared to its mass?
According to Wikipedia the Moon's mass is about 1.23% of Earth's but its gravity is 0.1654g, or 16.5%. If gravity is proportional to mass, why isn't the Moon's gravity 1.23% of Earth's?
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White full moon reflected orange-red light off of Atlantic Ocean surface. Why is this?
I was flying over the Atlantic at night in near complete darkness. There was a white, bright full moon. It’s moonglade (the light reflected off the waters surface) was a orange-red color and not white....
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How does the moon affect the position of zero gravity in the Earth?
I am interested in the position of the point of zero gravity within the Earth as a function of the gravity of the moon. Take the example of the moonless Earth. The position of zero gravity would be ...
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Do solar flares move the dust on the surface of the Moon?
The TV show For All Mankind has a reputation for scientific accuracy, so I think it's fair game to ask if it lives up to this reputation.
In this video clip, we see the dust on the surface of the Moon ...
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NASA's explanation on tidal acceleration
I've found an animation in NASA's website, illustrating tidal acceleration effect between the moon and earth.
It's the forth animation from the top in this page:
https://moon.nasa.gov/moon-in-motion/...
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Black body side of the Moon
A few closely related questions regrading the Moon thermodynamics:
The Moon is clearly not a black body, as it reflects a great deal of radiation incident on it. Still, it does absorb some radiation ...
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Why do moons not get pulled into the planet while they clear their neighborhood? [duplicate]
Today, my 6 year old and I were discussing dwarf planets and their characteristics. We were talking about how, to be a considered a planet, the planet needs to clear it's neighborhood (as explained in ...
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Could a moon keep orbiting a planet forever?
Our Moon orbits the Earth further away each year due to the tidal forces but could there be a moon orbiting a planet where somehow keeps going further away by the tidal forces but its attracted again ...
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What's the time window for total and narrow eclipses?
Because of the tidal effect angular momentum is transmitted from Earth rotation to the Moons orbit around Earth. This means that perfect eclipses only has occured during a certain time window. Can ...
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Is the position of the central peak of a crater on Moon showing that an asteroid hit it while it was not still sinchronised with Earth?
Is the position of the central peak of a crater on Moon showing that an asteroid hit it while it was not sinchronised with Earth? If the peak is in very center of the crater and the crater shown on ...
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Why is it so dark during a solar eclipse?
At a total solar eclipse the sun is barely covered, like right after sunset. So why is it much darker than right after sunset (which allows us to see the corona)?
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Are there any plans for cosmic ray detectors as part of the new ARTEMIS program?
NASA's new Artemis program involves building several temporary waypoints around and on the moon. One of the side-bonuses for scientists is that this has opened a few new funding avenues for studying ...
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Maximum solar power on moon [closed]
What is the maximum power that could be generated by covering the moon in solar panels?
Assume the entire lunar surface is covered and that the currently most efficient solar panels are used.
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Are there any moons that exhibit a non-convex curvature in their orbit about the Sun?
In my answer at https://physics.stackexchange.com/a/266444/59023, it took me several iterations before David Hammen and others could help me understand why the Earth's moon's orbit about the Sun is ...
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Why Moon is not falling on Sun (Hill's sphere)?
The Hill's radius of Earth in Earth-Moon system calculated by formula https://en.wikipedia.org/wiki/Hill_sphere is 58212 km
But the distance between Moon and Earth is 384,400 km
So, why Moon is not ...
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What is the relationship between crescent moon and position of the sun? [duplicate]
This is a phenomenon that involves the angles between the points of a crescent moon and the apparent position of the sun. Step outdoors on a day and time when you can see the sun and a crescent ...
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Earth, Moon, gravitatioal pull
Does the gravitational pull that causes tides, also affect the Earth's land mass. Does it affect the atoms, molecules, is there a slight bulge to the actual Earth / Land itself?
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Could the moon's centrifugal force generate the same acceleration as 9.8 m/s$^2$? [closed]
If one dug into the moon, could one reach a point where the centrifugal force is close to that of Earth's gravitational pull? If so, how deep would one have to dig? If not, how close could one get to ...
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Distance of the Moon Cycles
Recently, I started to search more about the orbit of the moon, and noticed there are certain periodic patterns or cycles for which I did not find any satisfactory explanation.
The first cycle can be ...
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Moon gravity space low gravity [closed]
How is it possible that a man or woman without equipment will "float" on the moon, but a photo can be left lying on the surface without anchor and not float away?
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Should the Rayleigh scattering of blue light somehow 'paint' the Moon image in the sky slightly in blue?
Should the Rayleigh scattering of blue light somehow 'paint' the Moon image in the sky slightly in blue? Maybe the Moon light is too intense during the day for that kind of effect to take place as ...
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Is it a coincidence that distance between Sun and Earth=(Distance between Earth and Moon)*(365.25+24) or is there any logical reasoning behind it? [closed]
Here $365.25$ days is the time taken for Earth's Revolution around the Sun while $24$ hours is the Earth's rotation.
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What would happen if I shot a near-light-speed bullet at the moon? [closed]
What would happen if I shot a bullet at 90% of light speed from earth to the moon? Would it make it through the atmosphere? Would it have any negative effects on the earth's atmosphere as it passes ...
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If you sliced the moon in half perfectly, would it hold together?
Just a big ol' slice down the middle. Would it drift apart over time, or eventually fuse back together?
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What is the logic behind this vis viva equation based calculation?
"If the moon were shrunk to having a radius of one meter, without changing its distance (of the apogee) from the earth, what would be the slowest it could be slowed down to and still orbit the ...
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If you could shrink the moon to one meter radius, how much could you slow the moon down by and have it continue to orbit the earth? [closed]
If the moon were shrunk to having a radius of one meter, without changing its distance (of the apogee) from the earth, what would be the slowest it could be slowed down to and still orbit the earth, ...