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Questions tagged [planets]

Celestial body that orbits following an elliptical path around a star or stellar remnant.

966 questions
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If Earth had rings?

If Earth had rings, would they center on the equator like Saturn's rings do on its equator?
Muze
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Why is the Earth so fat?

I made a naive calculation of the height of Earth's equatorial bulge and found that it should be about 10km. The true height is about 20km. My question is: why is there this discrepancy? The calculation I did was to imagine placing a ball down on…
Mark Eichenlaub
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How can we see planets thousands of light years away but don't know if there are more planets in the solar system?

That is basically my question, it arose when I saw an article (here is the scientific paper, which should be free to read) saying two Caltech scientists might have found the 9th planet of the solar system.
Suriya
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Is there a small enough planet or asteroid you can orbit by jumping?

I just had this idea of orbiting a planet just by jumping and then flying upon it on its orbit kind of like superman. So, Would it be theoretically possible or is there a chance of that small body to be & remain its unity?
Max Abrahamsson
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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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Does a star need to be inside a galaxy?

Must a star belong to a galaxy, or could it be completely isolated? In case it can be isolated (not belong to a galaxy), could it have a planet orbiting around it?
cooper
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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…
Hsvkd
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Why don't planets have Circular orbits?

This might be a completely wrong question, but this is bothering me since many days ago. Given the mass (Sun) curves the space around it, gravitation is the result of such curved space (Correct me if I am wrong, source: A Documentary film). Given…
aravind ramesh
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If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards?

If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards?
Casimir Rönnlöf
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Would you be weightless at the center of the Earth?

If you could travel to the center of the Earth (or any planet), would you be weightless there?
freeside
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Why does the Earth even have a magnetic field?

From my knowledge of magnetism, if a magnet is heated to a certain temperature, it loses its ability to generate a magnetic field. If this is indeed the case, then why does the Earth's core, which is at a whopping 6000 °C — as hot as the sun's…
Rumplespaceking
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Could there be a star orbiting around a planet?

I wonder if there ever could be a star (really small) which may orbit around a planet (really big)?
Ashish P
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Why does the Moon face Earth with the same side?

I know that the rotation period of the moon equals its revolution period. It's just so astonishing that these 2 values have such a small difference. I mean, what is the probability of these 2 values to be practically the same? I don't believe this…
Alex
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Does bottle water rise a little bit on full moon days?

High tides and low tides are caused by the Moon. The Moon's gravitational pull generates something called the tidal force. The tidal force causes Earth—and its water—to bulge out on the side closest to the Moon and the side farthest from the Moon.…
user218113
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Is there a maximum distance from a planet that a moon can orbit?

Given a planet that orbits a star, and a moon that orbits that planet, is it possible to define a maximum orbital radius of that moon, beyond which the moon would no longer orbit the planet, but the star instead? I initially (naively) thought this…
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