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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What is this 877-year cycle in the orbits of Jupiter & Saturn, and this multimillion-year cycle in the lunar orbit?
The book The Theory That Would Not Die (by Sharon Bertsch McGrayne, 2011) states the following on page 28:
He [Pierre-Simon Laplace] used other methods between 1785 and 1788 to determine that Jupiter ...
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Earth-Moon Barycenter Perihelion
I am trying to implement an algorithm I created to get the sun rise, transit and set accurately, but in order to do that I need to get the Earth-Moon barycenter (EMB) perihelion, and not the Earth ...
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Can the Earth be seen from the moon when we have a total lunar eclipse at the perigee?
We know that the Moon doesn't have an atmosphere; thus the sky is seen dark.
Also, from this question, the angular diameter of the Earth viewed from the Moon is a bit bigger than $2^\omicron$ at the ...
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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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The moon rises at a different time each day, but that difference changes. Why?
Let's say the moon rose at 5pm yesterday and 5:30pm today. The difference is 30 minutes – but that difference changes from day to day and can be anywhere between twenty-some to seventy-some minutes. ...
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Moon path diagram for a location
There are a lot of sun path diagrams online (i.e. https://www.gaisma.com/en/location/seattle-washington.html), but I'm struggle to find a moon path diagram. Is that called something different?
I'm ...
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Earth-Mars-Moon or No Moon Barycenter Orbit Possible?
Could an object of sufficient mass deflect Mars so that it ends up stably orbiting an Earth-Mars-Moon barycenter? What would the distances eventually become between each orbiting body?
What if the ...
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What if Earth’s moon started rotating?
Hypothetically speaking, what might happen to Earth if one day the moon became un-tidal locked and started to rotate?
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When does DSCOVR see the Moon transit Earth?
In 2015, NASA published the first images of the Moon transiting the Earth as seen from DSCOVR. The text accompanying these images says such a transit would be captured on camera about twice a year.
I ...
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How strong is the evidence or argument for the Moon as stabilizer of Earth's axial tilt? [duplicate]
It's thought that the Moon stabilizes Earth's axial tilt, and so without it, seasons as we know them could not exist i.e. there could be extremes during periods where the tilt approaches 90 degrees. ...
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What ground-based observational evidence is there that the Moon doesn't have an atmosphere?
The Moon doesn't have any significant atmosphere (surface pressure is $3\times10^{-15}$ bar). Can the absence of atmosphere on the Moon be determined with ground-based observations? When was it first ...
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Tips of Crescent
Can it be shown mathematically that the line connecting tips of crescent is parallel to the North-South line and the line gives latitude of the plane ( When the Moon is sufficiently close to the ...
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Can I use 75mm Plano convex lens to build telescope [closed]
I want to see Jupiter with moon.
So am planning to build telescope. Can I use 75mm Plano convex lens with 1000mm focal length?
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Sun Moon earth Angle
I want to do a theoretical prediction before trying out an experiment. I just noticed that the arc separating the illuminated side of moon and the shadowed side is an ellipse arc. So Is it possible to ...
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Would anything be different on Earth if the rotation of the Moon wasn't synchronous?
The Moon is in synchronous rotation, meaning the same side of the Moon is always pointing towards the Earth. My intuition is that it wouldn't make any difference (other than the fact that the whole ...
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Is the high-low tide difference greater, on average, at new moon, full moon, or neither?
The difference between high tide and low tide peaks when the moon is full and also when the moon is new. At both of these points in the lunar cycle, the tides are known as "spring" tides.
On ...
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At what rate does the right ascension and declination of a planet, the sun and moon change per hour?
I'm currently building a web app and am getting the RA's and Dec's of solar system objects based on date and time chosen by the user. Then using the gmst for 0 hours of the date, the app calculates ...
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Where in space would the Earth and Moon appear to be the same size?
If I'm directly in between the Earth and Moon, what distance from the Earth would I have to be so that the Earth and Moon have the same apparent size?
How big would the moon appear compared to it's ...
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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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How old is the idea of the far side of the Moon?
The far side of the Moon is the side which always faces away from the Earth, due to tidal locking. Due to libration, about 18% of this far side can be seen at one point or another through telescopes.
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Which edge of the Moon was deeper submerged into the Earth's shadow?
I was trying to solve this little task:
An Australian astronomer at the latitude of Melbourne (-38 °) observed a series of unusual events. First, he watched the setting of the sun and the rising of ...
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Where is it possible to observe the Moon for 24 hours?
I wrote an astronomy olympiad yesterday and there was one task I couldn't figure out an answer to:
Estimate at what latitudes it is possible to observe the Moon for at least 24 hours. Under what ...
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Can you see the shadow of a spaceship on the Moon while looking towards the Earth?
It's a classic movie cliche. We see the surface of the Moon with the Earth in the distance and a dark shadow of an invading alien spaceship slowly covering the landscape.
We see this in the opening ...
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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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do meteroid impacts occur evenly across the entire moon surface?
Since the moon is tidally locked and has the same face showing to the earth, I would expect that the earth's shadow represents an area on the moon that would be spared some meteoroid impacts. Does the ...
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Up to what distance from the Moon does the Moon's gravity hold its exosphere before it is being cast away by solar wind?
Up to how far from the Moon is the Moon's exosphere gravitationally bound to it? For the Earth's exosphere it is 120,000 mi (190,000 km) or half the Moon's distance from the Earth, beyond that the ...
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Why Does Moon Evection formula use the mean position instead of the true position?
Reading Wikipedia on the Moon Evection, and was somewhat surprised to find there that the formulas to express the evection are using the Moon's Mean position (mean anomaly) instead of its True ...
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Am I looking at the moon upside down here in the US?
This may be a very basic question, but I just learned that the moon orbits around the earth counterclockwise. I always thought the earth and the moon shared the rotation and orbit direction. Since the ...
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Why does our Moon not have rings?
While our Moon is full of craters, one could consider that these events might have been enough to release amounts of fragmented mass into the Moon's orbit sufficient to establish some sort of ring.
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Structures on the Far Side of the Moon?
I downloaded an image of the far side of the moon using Google Earth. It is an area to the North West of the Mare Moscoviense (lat 27.3$^{\circ}$ lon 147.9$^{\circ}$)
What are the dot-like structures ...
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Why does the difference between terrestrial times and universal time, $\Delta T$, have such a strange behaviour?
I was reading about ancient astronomy, and one of the main phenomena described is eclipses. Now, I read this 2016 paper by Stephenson, Morrison and Hohenkerk, in which they determine the values of the ...
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When can Moon occult Venus?
I'm trying to solve this task:
At what age of the Moon (in days after the new moon) is it possible for the Moon to occult Venus?
How I was solving it:
Angular velocity of the Moon is 13.2 degrees ...
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What percentage of the time can we see the moon during the day?
From sun rise to sun set what percentage of the time is the moon visible?
I saw one thing at the top of google saying an average of 6 hours a day but that seems like a weird way to answer it. Would ...
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Trying to find the source of these three orbital elements
I'm working through section 65 “Calculating the Moon's position” in Practical Astronomy with your Calculator or Spreadsheet (fourth edition) by Duffett-Smith and Zwart. They begin the calculations ...
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Can large scientific telescopes observe the Moon without being damaged?
When I look at the full Moon through my 10cm telescope, it is so bright that it hurts. Can large scientific telescopes observe the moon at all? Does that require special protection equipment? Or ...
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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 ...
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Is it a partial lunar eclipse or a partial phase of a full lunar eclipse?
I'm trying to solve this task:
What is shown in the photo: a partial shadow eclipse of the Moon or a partial phase of a total eclipse of the Moon?
I can't really understand it. Could somebody help ...
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What was the day of the week for the total lunar eclipse (saros 61) that occurred on April 14, 32 AD?
I am interested to know if there is convincing "astronomical" evidence/data to pin down the exact day of the week for the total lunar eclipse of April 14, 32 CE. I am hoping that perhaps ...
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When could solar eclipse happen in a way that Sun's disk is diminishing from below?
I'm trying to solve this task:
During a solar eclipse, an observer noticed that the diminishment of the Sun's disk began directly from below. Where and when could this be?
Concerning "where&...
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Why doesn't the Moon fall out of orbit?
If you need to boost ISS to stay in orbit why moon doesn't fall down to earth and KABOOM?
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Could there be an eclipse tomorrow if the Pleiades is covered by the Moon tonight?
I'm trying to solve this task:
Suppose today there is a covering of the Pleiades star cluster by the Moon. Could there be an eclipse of the sun tomorrow? The moon?
I think the answer to both is no, ...
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What would happen if the Sun, Moon and Earth were isolated?
I am curious to know what would happen to Earth and life on Earth if all other heavenly bodies outside of our Sun, Moon and our planet Earth ceased to exist in some non-destructive way? (this includes ...
user42433
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How to resolve the Moon's observed angular velocity with that given by Kepler's Third Law
According to the sidereal period of the Moon's orbit around the Earth of 27.32166 earth days of 86400 seconds we get an angular velocity of $\frac{2\pi}{27.32166×86400} = 2.6617×10^{-6}$. (NASA's ...
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Would people on opposite sides of the earth see different details of the moon, if so are there actual photos demonstrating this?
I am aware of phases and the fact that opposite sides will see the moon flipped relative to the other but what I’m asking specifically is would the almost 8000 mile difference between the two ...
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What is the size of the universe? [duplicate]
Will as a result of the continuation of technological progress in the twenty-first century more perfect telescopes or other astronomical instruments that will allow to know what is on the surface of ...
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What are the aspects does the moon differs between cities located on the same latitude?
What are the aspects does the moon (astronomical position and other astronomical aspects) differs between cities located in the same latitude? - For example: Seattle, Munich, Vienna, and Ulaanbaator ...
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How to find the the diameter of the moon during a total solar eclipse?
I am not able to find the diameter of the moon. I have the following question in my physics textbook:
During a total solar eclipse the moon almost entirely covers the sphere of the sun. Write the ...
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Moons with synchronous rotation in our solar system
Are all moons in our solar system rotating synchronously around their planet? If not, what are the criteria that some do and some don't?
Many thanks for any insights!
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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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What is Lawrence Krause's theory of total energies?
Does Lawrence Krauss theory say that the total energy in the universe is equal to zero or that the energy in the entire universe remains constant and the mass in the entire universe also remains ...
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