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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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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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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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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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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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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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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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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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 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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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 ...
user51331
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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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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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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 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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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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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 ...
user50623
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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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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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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 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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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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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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Does a planets mass affect its gravitational pull? Let's say earth increased or decreased in mass could that theoretically affect gravity?
This was a random thought I had, and I can't seem to find any answers. I was thinking that if the Earth shrunk that could possibly cause an increase in ...
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Do humans have the capacity to blow up the entire planet earth today? [closed]
For example, if we are able to gather all the available nuclear weapons in place and target towards a weak point, say an earthquake fault line, will the entire planet be blown to bits?
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What would happen if all water on earth including the oceans was placed evenly over the atmosphere of Earth? [closed]
Would that massive water body sit on top of the atmospheric bubble or would it fall to the ground? Would it rain water or fire instead? Would we see the skyes red instead of blue? What would be the ...
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What is the apparent size of Earth from the Sun?
Heatwaves have been in the news in recent years. I found it amazing to consider that the energy from the Sun is enough to kill you, when only a tiny fraction of its radiation reaches Earth.
Then I ...
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Effects of other planets on life on Earth
I've heard this often in the media, that the gas planet Jupiter has a significant effect upon life on Earth - by, the say, drawing asteroids & comets to itself, many planet-killer are destroyed as ...
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What kind of effects would two moons have on an earthlike planet?
On Earth our moon has several effects: it generates two high and two low tides a day; it slows down the spin of the planet and stabilizes its wobble, etc.
So, what possible effects could two moons, ...
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Is the speed of time much slower on sun surface?
The gravity forces on Earth and Sun is different and in Interstellar, they said something like high gravity slows time. So if we say Sun is N billion years old, that must be earth time but on Sun's ...
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Earth's Collision [duplicate]
It is my understanding that the Earth is tilted because it was struck by another object about the size of Mars.
According to Newton's first law, the Earth should have continued to rotate along its ...
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Why is Earth 1/3 the age of the universe?
The Earth is 4.6 billion years old
The universe is 13.8 billion years old.
3 times the age of the Earth
Are there other planets with ages that are close to say 1/4 1/5 etc the age of the universe? Why ...
user48394
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How long was a year 4 billion years ago, thus how long did it take the Earth to orbit the early Sun? [duplicate]
How long did it take the Earth to orbit the early Sun 4 billion years ago?
I'm not talking rotation, which I know has slowed over time. I'm talking about the orbital period of the early Earth. Was it ...
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Does anybody know how to solve this Earth-Venus-Sun problem?
How can I find (in terms of the angle) the moment when in the system Sun-Earth-Venus, Venus can be seen the most bright if its brightness (flow received in Earth) is proportional to the size projected ...
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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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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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How to show that a complete revolution of Earth around the sun takes 365 1/4 days?
Seasons change regularly and day and nights also.
The fact that Earth takes 365 1/4 days to complete one complete revolution was found a long way back in history, but so far I can't find any current ...
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A couple of questions about Earth's hypothetical planetary rings
From what little I know of this subject, It should be possible for Earth (Or a planet the size of Earth) to keep a system of Planetary Rings. However, looking around the internet only gives me info ...
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Does polar motion cause the Earth ellipsoid to change?
The Earth is oblate because it spins and is not a rigid body. Since its spin axis changes relative to its crust, then the meridian of maximum diameter changes too, right?
I understand that polar ...
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How do I calculate the closest point to the sun on Earth's surface?
Couldn't find an answer so here I come:
On 21st of June and 21st of December these points would lie on the tropics.
But what about the other days of the year?
Is there a simple formula to calculate ...
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