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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Why is only one side of the Moon visible from Earth?
Why do we only ever see the same side of the moon?
If this is to do with gravity are there any variables which mean we might one day see more than we have before?
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Why is the Moon receding from the Earth due to tides? Is this typical for other moons?
After reading the Q&A Is the moon moving further away from Earth and closer to the Sun? Why? about the tides transferring energy to the Moon and pushing it from Earth, I have a question:
How is ...
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How does the Moon move in the "night" sky as seen from the poles?
A photo in the NYTimes article Ice Surveys and Neckties at Dinner: Here’s Life at an Arctic Outpost has got me thinking.
During the winter months at either the north or south pole, when it is ...
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Will the Earth ever be tidally locked to the Moon?
From my basic understating,
Momentum is being transfered from the Earth's rotation to the Moon's orbit by tidal friction. The Earth's rotation slows down and the Moon receedes from the Earth as it ...
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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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Is the moon moving further away from Earth and closer to the Sun? Why?
According to The NASA Moon Facts page:
The moon is actually moving away from earth at a rate of 1.5 inches per year.
Why is the moon moving further away from the Earth? Is this a result of the ...
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Why doesn't the moon twinkle?
Stars twinkle because their light has to squeeze through several different layers of the Earth's atmosphere. So why doesn't the moon twinkle as well?
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Is it a coincidence that both the Sun and the Moon look of same size from the Earth?
The Sun is huge, when compared to the Moon. Despite the huge difference in their size and distance from Earth, is it purely coincidental that they both look almost the same from Earth?
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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.
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Red Moon a Characteristic of all Total Lunar Eclipses?
I understand that the redness of the moon during the total lunar eclipse last night/this morning (April 14-15 2014) is a reflection of the red light caused in earth's atmosphere due to Rayleigh ...
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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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How to calculate the nodal precession range of the Moon with respect to the celestial equator?
In the span of 18.6 years there is nodal precession of the Moon with respect to the ecliptic of 360 deg. But if we consider this precession with respect to the equator, we will find (unless I'm hugely ...
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Why does the Moon appear gray when passing between the Sun and the Earth?
Shouldn't the Moon appear as bright as a full Moon seen at midnight from Earth?
The photo was taken by DSCOVR at Lagrange point 1.
In the picture, The Moon appears dark gray. Of course the Earth ...
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Can you see man-made lights on the dark side of the Earth from the surface of the moon with the naked eye?
This question is prompted from a comment on this answer:
Could a person on the surface of the moon see man-made lights on the dark side of the Earth with the naked eye? If not, how much magnification ...
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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 ...
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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 ...
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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?
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Why doesn't the sun pull the moon away from earth?
If the suns gravitational pull is strong enough to hold much larger masses in place (all the planets) and at much greater distances (all planets further away from the sun then earth) why does it not ...
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Why moon sighted only in Kerala but not in rest of India?
I know for most of you the question may look silly, but Kerala is a state in India where the moon (Ramadan moon) will be sighted but not in rest of India.
I was reading the news article where I got a ...
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Why is there no concavity in the orbit of the moon around the Sun?
Such questions have been asked here and I have read the answers some of which are quite informative. However, I want an answer that's straightforward.
I have gone through the following paper by A B ...
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What orbital period would produce one New Moon (and one Full Moon) each year? What other effects would this produce?
I am interested to know whether it's possible for the moon to orbit the earth at such a rate that we would see only one New Moon and one Full Moon a year. If so, what other effects would we experience?...
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Is seeing the Apollo Moon landers via an Earth-based telescope that hard?
There are interferometers that fuse the images produced by multiple telescopes and achieve a resolution of 0.001 arcseconds. With changes, couldn't these observe the Moon landers? Is the reason why ...
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How much of the sun needs to be blocked in order to see a noticeable drop in brightness
I live in NYC and just experienced the eclipse. What fascinated me the most was that despite the fact that the sun was about 70% blocked, the area was not noticeably dimmer. If the news wasn't saying ...
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How does the Earth move in the sky as seen from the Moon?
I just want to be sure I am visualizing this correctly, because it seems odd. The Moon is tidally locked to the Earth but there are wobbles to its motion due to libration. So from a point on the ...
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Where do we have it from that the Moon is migrating away from Earth?
I know Neil Armstrong placed a mirror on the Moon and people shoot lasers there which get reflected, thus measuring the time the light needs they can conclude the current distance of the Moon. But the ...
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Why is the Moon's orbit so complicated?
I like to think I have a good enough understanding of astrophysics but there's still one thing that I just can't explain.
Why does the Moon orbit the Earth the way it does?
Many other moons in the ...
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Moon's orbit around the Sun
The Earth revolves around the Sun and the Moon revolves around the Earth.
Out of curiosity I started thinking about the orbit of the Moon around the Sun and expected (assumed) it to be as follows:
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Has radio astronomy ever been done on objects that appear very close to the Moon? Is this avoided?
This answer to Which kinds of astronomical observations most need to avoid the Moon being up? mentions
For completeness - radio, mid-infrared and mm-wave observations are unaffected (unless the ...
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What is the **actual** average distance of the Moon from Earth?
The Moon orbits Earth at a semi-major axis of 384400 km, with its periapsis being 363300 km and apoapsis being 405500 km. (All figures from this NASA fact sheet.)
If the Moon orbited Earth at a ...
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How is this picture of the moon possible?
I need help understanding this images I personally took. If the phases of the moon are determined by the position of the earth, moon & sun. Then how is the moon a crescent while it is rising in ...
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Why do Earth and moon move apart but binary black holes move closer?
According to the accepted answer on Is the moon moving further away from Earth and closer to the Sun? Why?, the moon is receding from Earth because tidal forces and friction cause energy to be lost.
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Why does the planet Saturn have numerous (62) moons compared to the rest of the planets in the Solar System?
Saturn is a gas giant like Jupiter. It has everything from
tiny moonlets less than 1 kilometer across to the enormous Titan, which is larger than the planet Mercury. Saturn has 62 moons with ...
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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 ...
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How to find Exomoons?
How would we be able to detect Exomoons? We detect exoplanets by seeing if the light gets faint from a star, but could we really use the same method for determining if there is an exomoon around that ...
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Why haven't I seen the Moon?
It has been some time since I've seen the Moon. What are the conditions that might affect whether or not the Moon is visible within a 24-hour period?
Please take into consideration any notable ...
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Is there any residual oscillation left from the Moon rotation?
The Moon is tidally locked to Earth - a long time ago it was spinning, but after a time, the spin stopped - two factors stabilizing it: unequal mass distribution creating an equilibrium position where ...
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Where exactly does the Moon flip, given that it appears the other way up in the other hemisphere?
I've read in multiple sources that the Moon appears the other way up in Northern Hemisphere vs Southern Hemisphere. Here is one that explains why: Does the Moon look different in the northern and ...
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When will the last total solar eclipse occur?
Because the moon distance from earth grows, how long will it take, that it is no longer possible to see a total eclipse but only circular eclipses? And does it make a difference if you are on the ...
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Why is this moon red?
I wish I could attach a good quality photograph of this red color moon I'm looking at right now.
I searched on internet but there was no lunar eclipse scheduled to occur on 23rd December 2018
in ...
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Do we know the fluctuations and constant temperature depth of the moon?
Disclaimer: I have no formal scientific training.
From what I understand, surface temperature effects on Earth extend only so far into the ground so that at a certain depth the temperature remains ...
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Is this photocomposition of Andromeda's galaxy and the Moon accurate?
I recently saw the below image circulating around twitter/Facebook/reddit. It is titled "Andromeda's actual size if it was brighter":
One of the comments provides a link to another ...
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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 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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Was lunar libration first observed or first predicted? In either case, who was the responsible party?
How old is the idea of the far side of the Moon? got me thinking that as soon as we see the moon librate we have to come to terms with there being even more of it we can't see.
The Moon's libration is ...
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Why are most lunar maria on the visible side?
Is there any reason why the Earth side of the Moon has enormous plains and mountains, while the far side contains just few small ones inside largest craters?
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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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How bright is the full Earth during the lunar midnight?
At lunar midnight (i.e. the new moon as seen from Earth), the Earth is in its full phase with its entire disk in sunlight, and it is the brightest object in the lunar sky. How bright is it, and how ...
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Is the moon "perfectly" tidally locked and, if not, how long would it take us to observe it's rotation?
I have a general understanding of how and why a body in space can be tidally locked to it's planet or sun and I'm aware that our moon is in such a state.
My question is, if our moon once had a ...
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When did the Moon become tidally locked to Earth?
According to various theories the Moon was created around 4.5 billion years ago. About all of these theories suggest that it was rotating around its axis at that time though. Currently, Moon is at ...
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Can Earth host another natural satellite than the Moon?
Are there orbits with long-term stability (astronomical time scales) around Earth? Low altitude orbits will decay due to friction with Earth's atmosphere. Inside Earth's Roche limit, a Moon could not ...
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