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Questions tagged [earth]

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.

Earth is the 3rd planet from the Sun, one of the 4 terrestrial planets (i.e., "rocky planets") in the solar system (the remaining 4 planets are gas giants). It is currently the only known planet to harbor life.

Different fields of science study Earth, including,

There is also an Earth Science Stack Exchange.

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Simple check for the global shape of the Earth

I have been on a date recently, and everything went fine until the moment the girl has told me that the Earth is flat. After realizing she was not trolling me, and trying to provide her with a couple of suggestions why that may not be the case, I've…
SBF
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How do I explain to a six year old why people on the other side of the Earth don't fall off?

Today a friend's six year old sister asked me the question "why don't people on the other side of the earth fall off?". I tried to explain that the Earth is a huge sphere and there's a special force called "gravity" that tries to attract everything…
Amal
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Why doesn't the Moon fall onto the Earth?

Why doesn't the Moon fall onto the Earth? For that matter, why doesn't anything rotating a larger body ever fall onto the larger body?
Adir Peretz
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What is the simplest way to prove the Earth is round?

Assume you've come in contact with a tribe of people cut off from the rest of the world, or you've gone back in time several thousand years, or (more likely) you've got a numbskull cousin. How would you prove that the Earth is, in fact, round?
tQuarella
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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 hole? If there would be no change, why not?
Mia Clarke
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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?
Martin
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Why does CNN's ‘gravity hole’ in the Indian Ocean dip the sea level instead of raising it?

Ref. There is a ‘gravity hole’ in the Indian Ocean, and scientists now think they know why According to CNN, the 'gravity hole' is an area of decreased gravity, compared with the surroundings. This article says that the lower gravity causes to sea…
Paul Uszak
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Is it possible to send all nuclear waste on Earth to the Sun?

If we neglect the danger of unsuccessful lift-off of the rocket and the cost, would it be physically possible to send all nuclear waste on Earth to the Sun? Will there be an obstacle that prevents this? For example, solar winds?
Mubin Icyer
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Proof that the Earth rotates?

What is the proof, without leaving the Earth, and involving only basic physics, that the earth rotates around its axis? By basic physics I mean the physics that the early physicists must've used to deduce that it rotates, not relativity.
user8721
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Was the 2013 meteor over Russia stronger than an atomic bomb?

Reports of the Russian meteor event (2013) say that it released more energy than 20 atomic bombs of the size dropped on Hiroshima, Japan: Scientists estimated the meteor unleashed a force 20 times more powerful than the Hiroshima bomb, although the…
BrianC
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Why is air not sucked off the Earth?

People said outside earth is a vacuum. But the air does not get sucked from the Earth's surface. Some said it is due to gravity and some said the speed of air molecules are not high enough to escape. We know vacuum will suck air like your vacuum…
Weidong Tong
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Why can't the Earth's core melt the whole planet?

Earth core temperature is range between 4,400° Celsius (7,952° Fahrenheit) to about 6,000° Celsius (10,800° Fahrenheit). Source Why can't the Earth's core melt the whole planet? In other words, what is stopping Earth from being melted up to its…
Dean Moxley
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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 is that the Earth as a whole is neutral, but that…
Hywel
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Why is a new moon not the same as a solar eclipse?

Forgive the elementary nature of this question: Because a new moon occurs when the moon is positioned between the earth and sun, doesn't this also mean that somewhere on the Earth, a solar eclipse (or partial eclipse) is happening? What, then, is…
JYelton
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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 earth, as classical education tells us, why is the core…
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