Questions tagged [earth]
Questions regarding the planet on which humans live; the third planet from the Sun.
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What does the Earth look like when viewed from Saturn?
Are there any data from spacecraft that visited that planet? How large the Earth is when viewed from that planet?
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Planets Named After Roman Gods, Except Earth
I’ve looked this up, but not necessarily sure the internet has the right answer. Why are the planets in our solar system named after Roman gods, except Earth, and why is only one of the nine planets ...
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What is the distance between Stephenson 2-18 and Earth?
The distance between Earth and Stephenson 2-18 is 19,570 light years (1.15×10¹⁷ miles). The thing that makes this reasonable is because the Earth is in the Milky Way Galaxy and Stephenson 2-18 is in ...
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Could the solar system survive in a void?
If the solar system were suddenly placed in the middle of a large void... would everything still function as normal?
Would we even notice any difference here on Earth apart from the night sky?
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Why don't scientists believe Earth's surface water came up from the mantle?
I read, periodically, that there is more water trapped in the mantle than there is in the oceans - possibly a lot more.
If so, why don't any geologists believe that Earth's surface and near-surface ...
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Mass accumulation rate and orbit-time of earth
According to me following reason of mass accumulation of earth has been completely overlooked so far.
The sunrays that fall on the oceans travel deep into water and finally get converted into mass ...
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Calendar times of equinoxes
I know that the dates and times of equinoxes are not the same every year, due to precession of the axis and perhaps other effects such as the year not containing an exact number of days. The ...
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How did the Earth come to be in orbit around the sun?
I'm not sure if this post should be in the physics subject forum, but this seems to fit here too. I have been reading a book about chemistry and how the universe came to be with the theory of stars ...
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Cooling the early earth
My son had this theory that the icy comets cooled the hot earth during the late heavy bombardment. What do we know about this cooling effect on the early evolution of the earth? He intended his theory ...
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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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Why does earthshine fade out when night comes and reappear on the next evening?
While watching the Moon in the thin-crescent phase (a few days after new Moon), I often noticed that the earthshine becomes noticeable near the end of civil twilight, and very noticeable during ...
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Why are most cosmic rays positively charged? Has anyone figured this out yet?
It is by now very common knowledge that the vast majority of (known) cosmic rays are protons, alpha particles and such, yet I cannot find in my recent reading any discussion of why this might be, or ...
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Why isn't a month 28 days?
1 days is a rotation of earth. 1 years is an orbit of the sun. I've always beleived that one month is 1 period of the moon orbiting earth but the inconsistent distribution of days throughout the ...
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Why does time pass faster in moon than the earth?
One of my friends said that,
time passes faster in moon than the earth
Why does time pass faster on the moon than on the earth?
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Are there any softwares which help in simulating different experiments regarding flight of aircrafts on different terrestrial planets of solar system?
I have a few experiments on aircrafts whose results I am aware of if performed on the earth's surface. However, I am searching for software(s) that can help simulate the same or other experiments on ...
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What does the rate the Moon moves away from Earth depend on?
Is it based on the distance between the Earth and Moon? Would that make the Moon move away faster or slower as time goes on?
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How one can establish that the Earth is round?
I am asking this question out of curiosity.
Currently, I am reading the book: A Brief History of Time. In Chapter 1, the author discusses about Aristotle's conclusions about spherical Earth.
For ...
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Will the Earth tidally lock to the Moon (ignoring Sun's expansion)
At some point, won't the tidal forces from the Moon be less than the ones from the Sun? Would that mean that the Moon stops moving away, or would the process still continue. Would the Earth start ...
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How will the Solar tides affect the Earth's rotation once it is tidally locked to the Moon?
It is my understanding that the tidal forces of the Moon acting on Earth cause it to slow down its rotation and, because angular momentum is conserved, the Moon's orbit subsequently expands. This ...
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Would the Earth and Moon still have tides after the Earth tidally locks to the Moon?
Ignore the Sun's expansion.
From my understanding, tidal locking happens from torque as a result of tidal bulges being offset from the line between the two planets. So when the Earth and Moon tidally ...
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How far should we be from Earth to see a half Moon while it is seen as a crescent on the Earth?
When we see a crescent Moon that means it should be seen a half Moon from another position in the sky, because the terminator line (i.e. the line that separates the bright and dark areas of the Moon) ...
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What would happen if Venus and Earth collided?
The first thing we would need to consider is that Earth has already been hit by a protoplanet half its size 4.5 billion years ago, meaning the Earth may have a chance of staying intact after the ...
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To what extent does the increased average airmass the Sun's light passes through contribute to the seasons?
The traditional explanation for the cause of seasons I have heard is that because of the angle of the axis of the Earth with respect to the ecliptic, the angle at which light rays hit the Earth's ...
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If the distance from Earth to the Sun was filled with air, how loud would the sun be?
Based on this question: If there was air between the Sun and Earth, how warm would we get?
Many sources state that if sound wasn't limited by matter, we would hear the Sun at around 100dB constantly, ...
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Whis my planetary volume formula wrong? (volume = mass/density)
I'm having trouble with this and am unsure what I'm doing wrong. Let's use Earth as an example.
Earth has a mass of 5,972,168,000,000,000,000,000,000 (5.97E+27) kg and a density of 5513.4 kg/m3 or 5....
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Is this definition of tidal locking really satisfying?
We always are hearing this: "If a moon has equal rotational and orbital periods it's tidally locked to its host planet and always one side of it will face to the planet."
But what if, for ...
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How did Ptolemy prove in the following excerpt that the Earth is not cylindrical?
I have trouble interpreting the following excerpt:
“Nor could it [the Earth] be cylindrical, with the curved surface in the east-west direction, and the flat sides towards the poles of the ...
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How does Ptolemy prove in the following excerpt that the Earth could not be outside of the axis spanning between the poles of the celestial sphere
I have trouble interpreting the following excerpt:
“Against the first of these three positions militate the following arguments. If we imagined [the earth] removed towards the zenith or the nadir ...
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What effect does Earth losing a part of its mass have, is there an impact on the Earth's orbit around the Sun?
This is a random question that popped into my mind. I'm not a physicist or astronomist, however, I am genuinely curious. Also, this is not intended as a science fiction question, but an actual science ...
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How do the phases of Venus prove heliocentrism?
I have been doing research about the Copernican Revolution, and one of the main arguments that caused many astronomers to change their minds was Galileo's observation of all phases of Venus.
The proof ...
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Does the earth spiral around the sun's movement/motion path?
I have watched the following video (How Earth Moves by Vsauce) regarding how earth moves:
I have some questions:
Does the earth spiral around the sun's path as it is ...
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Which is brighter, Mars as seen from Earth, or Earth as seen from Mars?
At their closest flyby, Earth is ‘new’ and dim from Mars, and Mars is ‘full’ from Earth and brightest as seen from Earth.
When Earth is 39 degrees from the Sun then Earth is brightest as seen from ...
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largest balanced mass objects in Earth's L4 & L5 Lagrange points?
What is the largest single-object mass that would allow two objects of equal mass to have a stable orbit, one each, in Earth's L4 and L5 Lagrange points?
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why does earth have speed?
I understand that Earth has a quite big speed such as it ends up around the orbit. The sun can't really attract it till the end due to Earth's speed and earth really can't escape due to gravity, hence,...
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What would the night sky look like after 200 years?
It is research for a book I am writing. The year is 2200. Assume the volume of items in orbit has increased dramatically from today’s numbers. We go to war and blowup all the satellites. Four hundred ...
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Conditions on Earth when Mars was warmer, wetter & had a thicker atmosphere
To the question, What part of a star's habitable zone has the best chance of developing life?, I made the following comment:
It's always intrigued me as to why some people have thought that life in ...
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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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What is the maximum size for a solid celestial body such that it still can be tunneled down to the core?
Old science fiction had lots of stories that involved people exploring the center of Earth, like for example Journey to the Center of the Earth, by Jules Verne. As Earth sciences advanced, this sort ...
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Can the distribution of Al28 across the Earth tell us if the solar system formed from a gas cloud that collapsed itself or by a supernova explosion?
A single supernova could have collapsed a gas cloud and left Aluminium 28 on one side of the Earth . If there were many supernovae in all directions that gradually sent material to Earth then the ...
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What (if any) role did Earth play in the evolution of the solar system?
We all know that Jupiter played a great role in the Solar System by cleaning up debris and dust from the Solar System, and deflecting asteroids. Saturn also played a similar role. Uranus and Neptune ...
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What is the chance that the Sun will not rise tomorrow?
What is the most likely natural astrophysical mechanism for the "Sun not rising tomorrow", consistent with our scientific knowledge today?
Background
The "sunrise problem - What is the ...
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About how many revolutions has the Earth made around the sun?
The Earth is about 4.543 billion years old.
However, the length of a year can be changed by anything from an impact to a natural cycle of orbit changes to a slow drift toward or away from the sun to ...
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Convert from magnetic coordinates to true coordinates
I am working with the IGRF (International Geomagnetic Reference Field) model and from a journal article found here, I am able to compute the earth's magnetic field at any point in spherical ...
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Is the solar system barycenter affecting the Earth weather?
I do not have the numbers but I guess the solar system barycenter should move much more than the Earth radius, and if that is correct then it should not be affecting the Earth's temperature.
I mean, ...
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Polar day length
On Earth, are north and south polar days the same length? If not, at what latitudes north and south would they become equal? Or, what resources could I use to answer this question?
I am referring to ...
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Why is the solstice the first day of summer, and not the central day?
Summer in the Northern Hemisphere starts on the day of the summer solstice. This is the day that the Northern Hemisphere receives more light from the Sun, due to the Earth's tilt. To my knowledge, the ...
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Different results for the same JPL Horizons query
On JPL Horizons website, I'm using the following query to get vector state for Earth:
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Why are perihelion and the shortest day in the northern hemisphere different?
The orbit of Earth is elliptical and the nearest distance to sun is perihelion position. Should it not be the shortest day in the northern hemisphere?
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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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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 ...
