Questions tagged [planets]
Celestial body that orbits following an elliptical path around a star or stellar remnant.
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Does Jeans instability apply to the gas cloud that formed the solar system?
I have read that stars can form when massive gas clouds collapse because the gravity of the clouds is strong enough to pull their molecules together. The solar system formed from a gas cloud. Did that ...
user568422
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How does the Moon's tidal force affect Earth's equatorial bulge?
The equatorial bulge of a planet is affected by the planet's rotation and the viscoelasticity of the sphere. Venus's rotation period is 244 days with an equatorial bulge of 0%. Earth's and Mars's ...
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Some simple questions about the Earth [duplicate]
How is it possible to verify the roundness of the Earth? How can its size be estimated by physical measurements and no complex scientific instruments?
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Is it possible for "gas moons" to exist?
Is it theoretically possible for there to be such a thing as a "gas moon" as opposed to a rocky one?
Do any laws or models specifically prohibit the formation of gaseous moons?
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Correct form of apparent weight due rotation of Earth
I have come across two seperate formulae for the apparent weight/acceleration due to the Earth's rotation and the centrifugal force caused by it:
$g'=g-R\omega^2\sin^2\theta$
$g'=\sqrt{g^2-R^2\sin^2\...
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How do I calculate the maximum possible atmospheric density/ surface pressure a planet can have?
I'm not entirely sure if this is the right stack but here goes.
I'm trying to design a fictional planet that has less gravity than Earth but I would like to give it an atmosphere as or even more dense ...
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Why doesn't Mars's or Venus's axial tilt change without large moons, but Earth's is believed to?
It is claimed that the moon stabilizes the Earth's axial tilt, but Mars and Venus (and Mercury, too) are rocky planets without large moons. Why are their axes stable?
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What is gravitational pressure at a distance $x$ from center or Earth?
What is gravitational pressure at a distance x from center or earth. Assume earth to be spherical and with no atmosphere. Assume that earth has uniform density ,R is radius of earth and M is its mass.$...
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How does the scale height of a planet's air at temperature $T$ relate to how high a ball would go when launched up at RMS speed of an air molecule? [closed]
I shortened "atmosphere" to "air" to fit the whole question in the title.
The ball is of course launched in a vacuum (i.e. the atmosphere is first removed).
Is this question given ...
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Why does Earth have the largest mean density of all the planets in the solar system?
Browsing the density of the planets (and Pluto, Ceres, Sun and Moon) in the solar system, I observe that Earth is the one with the largest mean density: $5494 \ kg/m^3$. Is there a physical reason for ...
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Can there be an exchange of angular momentum between a planet and its atmosphere/liquid layers?
Consider a fast spinning planet with no outer influences (no outer thermal and gravitational influences like a star)
Could there be an spontaneous* exchange of angular momentum between the planet's ...
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Can there be wind and/or liquid currents driven by a planet's rotation?
Can the rotation of a planet alone provoke any kind of wind or liquid current?
Can the atmosphere, at least in some cases, have wind currents driven by the planet's rotation?
And can liquids also move ...
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Mississippi river and the equatorial bulge [duplicate]
Because the earth bulges near the equator the source of Mississippi river, although above sea level is nearer to the centre of earth then its mouth, how can a river flow uphill ? Is it due to high ...
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What is the value of $g$ 1 meter off the center of Earth? [duplicate]
Newton’s theory suggests it’s close to zero, but what says GR?
Edit 1: It’s obvious that at the center it’s zero for both theories. The curvature explanation of GR could give a different answer around ...
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Can two bodies be charged to escape Earth's gravity?
A random thought.
The picture that I have in my mind is that when two similarly charged bodies (Charges of very large magnitude) are kept closely, they will shoot away from each other and if they ...
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