Earth is the planet on which we live, the 3rd planet from the Sun. Questions using this tag should be about Earth the planet and not Earth-like planets nor earth, as in dirt or soil.

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Does Earth's loss of internal energy to the moon reduce local entropy?

[ edit: Since posting this I had 3 very contrary thoughts: 1) If the moon had been orbiting faster than the Earth, to the same degree, it seems like everything would be the same except that ...
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2answers
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Does gravity have two directions?

Imagine a particle that interacts strongly with gravity, but not with any of the other forces, and does not interact with normal matter (this may be analogous to the description of dark matter, I'm ...
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rare High altitude balloon footage (highest peak before balloon burst 23034 metres) without fishe-eye lens [on hold]

Why does Earth appear flat so HIGH UP in the sky? https://www.youtube.com/watch?v=jDs2T2PgxNM
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Change of Earth's Rotation [closed]

At the time of global warming, all the ice will melt, resulting the reduction in spinning of earth, Initially. But, if earth's surface temperature rises continuously for a long time, exactly this will ...
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2answers
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Why is there ice at the Earth's poles? [duplicate]

I beg your pardon for such a silly question, but I've never really understood the explanation they gave in the Geography textbooks. If the slanting Sun's rays due to the Earth's axial tilt can cause ...
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How far do we need to be removed from the earth to show the curvature with a viewing angle between 42 and 48 degrees? [duplicate]

I have seen already a couple of answers but none of them give an exact number of what should be the minimum height where we would be able to record the curvature of the earth All I could find is ...
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How do stars from far away affect Earth?

I know that we obviously get light (or we wouldn't be able to see them), but are there any other ways that they affect Earth and maybe just our solar system in general?
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How do I experience Earth's movement?

We are told that Earth is spinning on its axis at 1037 mph— something that we don't usually feel because of the environment that moves with us as well. Is there any experiment with which we can know ...
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2answers
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Reduction of Earth's rotation due to increase in humidity

I came to know that, moon is moving away from earth, resulting reduction of Earth's rotation. Similarly, if Earth's humidity increases, water vapor will be move up to the air from water sources, will ...
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If the Earth were a pool ball, could I feel mountains? [closed]

If the earth (12,742 km diameter) were scaled down to the size of a pool ball (61mm diameter), the mountain ranges would still exist, obviously. But would a typical human be able to feel those ...
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How much does the curvature of space change the volume of Earth by?

If we assume space is flat the volume of Earth is: $$ V = \frac{4 \pi R^3}{3} = \frac{4 \pi (6378.1 km)^3}{3} = 1.086 \times 10^{21} m^3 $$ The Einstein field equations, however, predict that the ...
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4answers
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Can the Earth leave orbit if the population of humans and other live forms increases?

I don't know a lot about physics, but this seemed like the correct place to ask my question. I apologize in advance if it is a ridiculous one. It's actually a two part question: If the population ...
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2answers
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Sun's tidal force on Earth

My question is regarding effect of Sun's gravity on earth. I want to know that if Sun's gravity can change Earth's landscape in long duration (i.e. billion of years) or not? Means if earth is dead ...
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Faster alternative to travel to any location in the west? [closed]

Suppose one needs to travel to Somalia from Indonesia(which are approximately at a distance of $4000$ miles from each other on the line of equator). To accomplish this task, I suggest the following ...
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Backyard experiments to falsify the Flat Earth theory [duplicate]

I recently became aware that the flat Earth theory still exists in the 21st century, and has colored the views of a friend of mine. Roughly speaking, the tenets are: The Earth is a flat disk, with ...
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2answers
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When sunlight bounces off the Earth, why isn't the entire spectrum reflected rather than just the infrared portion?

I've read that greenhouse gases absorb and reemit sunlight, and that the infrared portion is what bounces off Earth back to space. When sunlight bounces off the Earth, why isn't the entire spectrum ...
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3answers
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A gravity question [closed]

Does gravity have a unit like length is metres?
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2answers
4k views

What if the earth's core goes cold?

What effects would occur if the earth's core goes cold? Would the planet stay liveable after this happens?
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3answers
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Why does the sea horizon line always seems to be at the same height as one's eyes?

I wonder why, when I look at a sea/ocean, the horizon line always seems to be at the same height as my eyes, no matter how many meters I am above the sea level. This is something I noticed when I ...
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What is the net charge of the Earth?

This question arose in a seminar today about the solar wind... This is my vagueish understanding of the problem - please correct if you see errors! The 'classical' picture of atmospheric electricity ...
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Charge on Earth [closed]

We know that the Earth is neutral. But what will happen if the Earth becomes negatively charged or positively charged somehow?
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2answers
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Saturn V horizontally attached to Earth

If the Saturn V rocket were attached to the ground facing in the opposite direction of the Earth's spin, would it in anyway slow the Earth's spin on its axis? How significant of an impact would it ...
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How long was a day at the creation of Earth?

Since the earth is slowing its rotation, and as far as I know, each day is 1 second longer every about 1.5 years, how long was an earth day near the formation of earth (4.5 billion years ago)? I ...
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True or false: the Moon was touching the Earth 1.2 billion years ago

A creationist website makes this argument for the 6,000 year old earth. I'm embarrassed to say I don't know how to do the math to evaluate the claim myself. However, the time scales involved seems ...
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What is the maximum theoretical height upto which our oceans can rise? [closed]

The question is framed from a physics point of view so we will assume water is an indefinite resource. All I am interested in is if we go on adding water into our oceans then what is the maximum ...
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2answers
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Can we decrease the value of $g$ (gravitational pull) without gaining height? [closed]

The value of $g$ on earth surface is $9.8\ \text{m/s}^2$ and when we gain height, then the value of $g$ decreases. Pilots experience same phenomena in air, but can we decrease the value of $g$ by ...
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1answer
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Why lightning most likely occure in night?

This is a question based on my experience. I am not going to prove that lightning (succeed by thunder) never occure in day, but it seems it most likely occure in night. May the humidity of air become ...
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Earth's magnetic field

New researchs found that very high pressure on certain materials may reduce the degree of temperature required to change to superconductor. So is it possible that the high pressure in earth core ...
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1answer
165 views

Earth Maybe a Compass or Not [closed]

Does the Earth magnetic pole point to something in our solar system or farther? Like the Sun.
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Why is the geomagnetic north pole at a different location from the magnetic north pole?

According to this site Magnetic North, Geomagnetic and Magnetic Poles The Geomagnetic poles (dipole poles) are the intersections of the Earth's surface and the axis of a bar magnet hypothetically ...
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1answer
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How destructive would a small black hole be on the surface of the Earth?

Say a black hole with the diameter of around 200 meters or so was formed on the Earth's surface, how much damage would it cause?
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1answer
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Does Earth rotation effect planes? [duplicate]

What about the supposed aiming modifications when firing a weapon? According to my research, when firing a weapon you are supposed to aim a little to the right when firing northwards and to the left ...
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2answers
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Is the Earth's molten outer core affecting its motion?

According with the seismological studies [1] the outer core, with thickness of about $2300km$, starting from depth of $2,900 km$ and ending at $5,200 km$ is a low viscosity fluid, consisted mostly of ...
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2answers
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Triple-right triangle experiment: what's the minimum distance?

As I had showed in a previous answer, among the other ways to prove that the Earth is round, we have the triple-right triangle. The idea is simple: Starting from point A you move in a straight ...
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2answers
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Temperature of fusion in the Sun vs. fusion in controlled experiments on Earth

I recently learned that hydrogen fusion (i.e., hydrogen to helium) experiments on Earth have been successful at temperatures in excess of 100,000,000 degrees Celsius. However, I also learned that ...
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What is the general relativity explanation for why objects at the center of the Earth are weightless?

The idea that as you move through the earth you get a symmetric cancelling of gravitational acceleration which approaches zero acceleration due to gravity at the center of the earth makes a lot of ...
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If the earth is spinning and we are spinning with the earth, why doesn't it take longer to go opposite the rotation?

Imagine you are on a walking type platform at an airport where you are walking with the platform where it moves you faster walking with......than against. This would be the same concept as if we were ...
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How many hours will there be in a day 5,000,000,000 years from now?

It is known that the moon is moving away from Earth 2cm a year, and in doing so makes the days longer. I want to know how many hours will have one day, when our planet is near its end.
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Rotation of earth and effect on $g$ [duplicate]

How do we calculate the change in the acceleration due to gravity (consider earth as a uniform sphere) with a change in the rotation speed of earth along its axis? How do we build up a mathematical ...
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If the gravity at the center of the Earth is zero, why are heavy elements like iron there?

If gravity is zero at the center of the earth, why is there a core of heavy elements, such as iron? Alternate question for the opposite hypothesis: If gravity is greatest at the center of the ...
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4answers
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What would happen if the Earth was in a polar orbit around the sun?

This is a question that has been bugging me for a while now, I was wondering about the effects on the Earth if it was in different orbital situations to what it is now, and one of those was what would ...
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Why does Earth behave like Natural Bar Magnet?

What is the reason for the Earth to behave like a bar magnet and have poles (North and South poles)?
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How to determine satellite position in J2000 from latitude, longitude and distance from Earth?

Due to my task of writing orbit prediction routines I am trying to understand the reference frames better and how to use them ( particularly for Earth orbits ). I think I get the idea of what ECI ...
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2answers
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Why is there a temperature gradient on Earth?

I was thinking about why the poles are colder and I came out with three possible explanations. 1. The atmosphere blocks light beams coming to poles The Sun is seen only slightly over the horizon ...
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Why does the sun “shine brighter” some days?

Today, the sun seems extremely bright; more dazzling than usual, and even the roads seem to be brighter so it's not just when you look up in the sky. Is more light actually getting through (perhaps ...
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Effect of radiation pressure on Earths orbit in large timescales

I have seen some posts concerning the radiation pressure exerted by the Sun on Earths surface (Force on Earth due to Sun's radiation pressure). Though it is fairly small may it have a considerable ...
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1answer
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Earth as a conductor

In a lightning rod or other safety devices, charge is directed towards the earth. How the surface of the earth can be used as a conducting path despite being composed of material that is not a good ...
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1answer
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What is the longitudinal difference between the sub­solar point and the magnetic poles at time $t$ (hours)?

I'm trying to convert geomagnetic coordinate to geographic, but there are some steps in the paper which I'm reading, that I don't understand. I have the geomagnetic latitude centered around the ...
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Could moving land mass alter Earths gravity?

This is potentially a very stupid question but I'm going to ask it anyway. With all these huge buildings such as the Abu Dhabi Mosque, where an unbelievable amount of materials such as marble was ...