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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7
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1answer
4k views

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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4answers
129 views
1
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1answer
57 views

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 ...
1
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1answer
49 views

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 ...
0
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1answer
99 views

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 ...
6
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1answer
1k views

If the Moon had gravity as good as the Earth and a magnetic field could it have supported life?

If the Moon had gravity as good as Earth and a magnetic field could it have supported life? Because if the Moon had gravity, it could have retained water more than is present today on the surface. ...
0
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1answer
60 views

Is there any way to create a globe with gravitational or similar attractive force - earth simulator?

This may sound like a dumb question. Is there anyway to create a miniature version of earth or its gravitational force. A globe or sphere which have force inside it which can attract the things ...
4
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2answers
606 views

Deviation from Earth's orbit

How much orbital deviation is required for the Earth to get knocked out from current orbit so it either moves away from Sun or towards the Sun?
1
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1answer
48 views

What happens if an object stops orbiting the sun? [closed]

What would happen if an object (like a space ship) was to stop its orbit around the sun. would time slow down with that object (the same way time sped up for the characters in that great film ...
3
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3answers
2k views

How can we see the moon while it's between the Earth and the Sun?

I know this sounds like (and probably is) a stupid question, but I can't figure it out. As far as I know, the crescent shape of the moon is when the moon is on the sunny side of the Earth, but that ...
2
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2answers
42 views

Space station illuminated by the Earth

Let's say that we have a space station orbiting the Earth around the equator at a speed of 360 degrees per 24 hours, always being roughly on the line between the centers of the Earth and the sun. From ...
2
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2answers
115 views

Why is the acceleration due to gravity $g$ quoted as if it were constant?

In elementary physics courses the value $g=9.8\:\mathrm{m/s^2}$ is used almost universally. But surely this value must depend to some extent upon one's location on the Earth. Why do we assume a ...
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0answers
66 views

Why are the cores of planets melted?

We all know that the core of Earth is in liquid form, as are most other planets as recently read. Why is this the case? Obviously, high temperatures are the cause, but what causes the high ...
0
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0answers
39 views

How does magnetic field gets generated by friction between high temperature molten metallic cores?

I was watching "Strip the cosmos" show on Discovery science channel last day and they explained that earth produces magnetic field due to rubbing of the two concentric cores, both the molten metal ...
-1
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1answer
66 views

If Earth was split into thousands of astroid-size chucks, would any of them have gravity? [closed]

I know that mass increases gravity and that less mass decreases gravity. But is there a minimum gravity amount that won't let meteors or astroids have gravity because of their littler masses?
0
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5answers
75 views

Static model of the Earth motion

Believe it or not, an old man I know in 2015 still negates the Earth orbital motion around the Sun. He believes the earth is rotating on itself and acknowledges this gives day and night on every ...
0
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2answers
67 views

How do gravity anomalies on Earth comply with conservation of energy?

Gravitational acceleration varies from place to place on Earth in a range of about 0.02 percent and is caused by density distributions within the Earth. Imagine an experiment where you move around the ...
2
votes
3answers
108 views

(How) can we determine mid-point on Earth's orbit?

The eccentricity of earth's orbit varies with time, but at present time its eccentricity is roughly mean e (0.0167). The position of equinoxes is far more complicated than I thought and it is not at ...
2
votes
2answers
124 views

Why Earth is considered to be an inertial frame? [duplicate]

Earth rotates about its axis and also revolves around the Sun at the same time. So why Earth is considered as an inertial frame in Newtonian Physics. So technically, I'm effectively asking why the ...
16
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3answers
2k views

Are there any exact data about Earth's orbit?

Wikipedia says that the Earth's orbit's axis is $a=149\ 598\ 000\ \mathrm{km}$ and its eccentricity is $e=0.016\ 7086$, but if we use these values to find distance at aphelion and perihelion we get ...
0
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0answers
121 views

What altitude you need to see the earth's curvature? [duplicate]

i have seen several videos and articles that nobody has seen earth's curvature except nasa. if someone has tried to go up to see earth curvature it seemed flat to them which makes some people to think ...
3
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0answers
39 views

Different time between equinoxes

I calculated from here that there are 16 104 096 seconds between the vernal and autumnal equinox, if I made no mistake, this is some 650 592 s longer than the other half orbit. I imagine this is due ...
31
votes
5answers
8k views

If the Earth is a good conductor of electricity, why don't people get electrocuted every time they touch the Earth?

Since the Earth is a good conductor of electricity, is it safe to assume that any charge that flows down to the Earth must be redistributed into the Earth in and along all directions? Does this also ...
0
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0answers
77 views

How general relativity shows that gravity decreases as we go inside the Earth [duplicate]

Why is it that gravity decreases as we go deeper inside Earth? Can anyone explain theoretically with reference to general relativity?
16
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4answers
25k views

How does gravity work underground?

Would the effect of gravity on me change if I were to dig a very deep hole and stand in it? If so, how would it change? Am I more likely to be pulled downwards, or pulled towards the edges of the ...
8
votes
2answers
1k views

Why heavy elements don't sink to the core?

If earth assembled out of space dust, how come we find heavy elements like gold, silver, uranium and bunch of others that are heavier than iron on the surface? I mean silicon (Si mass 28.084) being ...
1
vote
1answer
41 views

Will my data drives be safe in an emp event? [closed]

If there was an emp event (maybe because the rotation of magnetism of the earth or an atomic bomb) would the data on my hard drives, ssd, dvd, mini dvi tapes and cassette tapes be safe?
0
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0answers
28 views

Are these reasonings about tides correct?

This is a picture of the "M2 tidal constituent": The nodes corresponds to fixed points, for which the moon has no influence on the altitude. 1. Static VS Dynamic problem? I was first wondering if ...
0
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2answers
768 views

about angle between magnetic axis and geographical axis of earth

How the angle between the magnetic axis of earth and the geographic axis of earth can be calculated?
3
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1answer
59 views

Relativistic effects of an orbit around sun in a different direction than Earth

If I manage to orbit around the sun at the same speed but in a different direction than the earth, will I perceive the time on earth going faster or slower than my own time? And what about people on ...
4
votes
3answers
2k views

Are we increasing the gravity of Earth with our population?

I have these questions related to my question title: Do we, other species and things have our own gravity? How much Gs a human have? Are we effecting Earth, nearby moons and planets with our ...
2
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0answers
21 views

The moon affects the motion of the oceans, but can the motion of the oceans affect the moon? [duplicate]

Obviously the earth's oceans have mass and therefore they have an attractive force upon the moon. However, let's say that we were to cover most of earth with tidal power generators that extract some ...
0
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0answers
49 views

Was Nikola Tesla right about the blast on earth? [duplicate]

It was said by Tesla that if we blast on earth at some specific coordinates then it can divide the earth into two parts .Is it really possible?
2
votes
2answers
421 views

Which will collide first, the moon and Earth, or Sun and Earth?

As time progresses, which scenario will happen first? The moon colliding with Earth, or the Earth colliding with the Sun? I figure the Moon and Earth will happen first, based on proximity, but the sun ...
2
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1answer
43 views

Earth precession

I got a bit confused while studying the tropical and sidereal years. I noticed that the Earth's precession is in the opposite direction than that of a top's precession, when their rotational direction ...
5
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5answers
16k views

What is the scientific reason for the inclination of earth's rotation axis?

This titled position of the earths axis is known as inclination of the earths axis. The earth's rotation axis makes an angle of about 66.5 degrees with the plane of its orbit around the sun, or about ...
4
votes
2answers
502 views

Rivers that flow “uphill” due to Earth's rotation

One of the fun tidbits that gets bandied around in physics departments is that the Mississippi River actually flows away from the center of the Earth. Due to the Earth's oblateness, the source of the ...
19
votes
3answers
5k views

How quickly was the Earth rotating 250 million years ago?

The Earth is slowing at a rate of $4.7\times10^{-4}$ miles per second every 100 years due to tidal forces of the moon. See: http://en.wikipedia.org/wiki/Earth%27s_rotation ...
1
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0answers
145 views

What is this bright spot in the sky?

This is my first question here so please be gentle! I took this picutre a few minutes ago (35 minutes ago, currently 1828 here) As you can see there's a VERY bright spot on the right that shows a ...
1
vote
1answer
342 views

How does the Moon cause the tides?

I am considering the following question, but I can't quite figure it out... I have looked up differential gravity, but I cannot derive the equation for the effect on Earth, and I haven't found any ...
42
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5answers
10k views

Why has Earth's core not become solid?

The Earth is billions of years old, yet its core has not yet cooled down and become solid. Will this happen in the foreseeable future?
1
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0answers
55 views

Why is gravity high at poles but lower inside the surface of Earth, as compared to $g$ on surface? [duplicate]

My high-school physics teacher recently displayed some formulae stating at when we dig deeper the gravity pull is lower but at poles (the flattened part) it is appreciably higher. Now, if we consider ...
1
vote
1answer
92 views

What is the outward force on the Moon that makes it go in orbit rather that falling straight to the Earth? [duplicate]

So, we know that the gravity is responsible for pulling the Moon towards the Earth. But because it moves in an orbit, it makes me think that there must be a force that is causing the moon to travel in ...
0
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0answers
46 views

Using an Earth magnetic or electric field to fly [duplicate]

Are there possibilities to use the magnetic or the electric field of earth to let a matter flow in space?
6
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2answers
3k views

How is the Earth heated by a Full Moon?

While the moon is certainly not a good reflector of solar radiation, surely the radiation it reflects back heats the Earth (even if it is a terribly small amount). How would one go about calculating ...
-1
votes
1answer
147 views

How much radiation does the Earth receive from the Sun's total radiation? [closed]

I was thinking how to solve this problem. $1\,\mathrm{AU}$ is roughly the distance from the Earth to the Sun, $1.4960 \times 10^{11}\,\mathrm{m}$. The radius of Earth is approximately $6.4 \times ...
0
votes
1answer
62 views

Could a big enough straw stretching from Earth to space eject atmosphere into space? [duplicate]

Assuming the straw can be built out of any material, shape, size. Would the vacuum effect of space acting on the pressurized gas have enough force to lift the weight of the atmosphere contained in ...
0
votes
4answers
111 views

Does not the mass of those living on the Earth add on to the mass of the Earth or is it too negligible to be cared for?

Source: Earth weighs about 13,170,000,000,000,000,000,000,000 pounds (or 5,974,000,000,000,000,000,000,000 kilograms). Since Earth is too big to be placed on a scale, scientists use mathematics ...
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2answers
153 views

Can we get energy from the Earth's rotation?

Is there any way to harvest large amounts of energy from the Earth's rotation?
0
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1answer
84 views

Gravity Relative to Mass?

Why is it that, in basic physics, it is taught that the acceleration of gravity is the same for objects of any mass (at a constant distance from earth)? Why then is the acceleration of gravity ...