Questions tagged [gravity]
The gravity tag has no usage guidance.
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How to compute spherical harmonics coefficients using orthogonality?
I use the lunar gravity model GRGM900C to calculate the gravitational potential across a $360{^\circ}*360{^\circ}$ grid. This calculation follows the equation:
$$V(\varphi,\lambda)=\sum_{\mathrm{n=0}}^...
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Why does weaker local gravity cause lower sea level?
The weaker local gravity in the Indian Ocean geoid low (IOGL) causes the sea level to be 106 m below the global mean sea level. Why is that ?
"Because of this lower density, the gravitational ...
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Which forces align objects with the rotation of the Earth and how?
I have a question about which forces cause alignment of objects with the rotation of the Earth and how:
It is known to me from public sources that objects up to a height of about 36,000 meters above ...
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Do gravity and magnetic field change along a geographic latitude or not?
Along the same geographic latitude does magnetic field change or not, and the same for the gravitational field, does it change along a geographic latitude? Please explain.
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What is a general formula for Earth gravity as a function of radius, given a spherical shell model?
I'm trying to derive the formula for gravitational acceleration as a function of Earth radius $g(r)$, given a spherical shell model where each shell has a constant density $\rho(r)$. If I set $r=0$ to ...
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Why is there a low gravity anomaly right next to a high gravity anomaly next to mascons on the Moon?
This is from the book "Isosatsy and Flexure of the Atmosphere" by A. B. Watts. According to him, evidence for the isostatic compensation of mascons (i.e. regions of higher density material ...
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Why is sealevel higher where gravity is higher?
The EGM96 geoid map depicts hypothetical sealevel due to gravitational variations on the Earth's surface:
image source
It places one of the highest areas in the northern part of the Atlantic ocean.
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How is the atmosphere expanding in all directions if Gravity is holding the atmosphere down to earth?
We are taught that gravity is the force that keeps the atmosphere and everything else binded to Earth. However, observable reality shows us that the atmosphere expands in all directions as it fills ...
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Do the 600 satellites that orbit the Earth have any gravitational pull on the tides like the moon?
I know that space is big and satellites are small compared with the moon, but do they have, or will they if we get more, any effect on the sea and ocean water on the earth?
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Would obliquity and precessional changes of Earth affect the accuracy of GPS-based measurement of tectonic movements?
The rate and direction of tectonic movements can be measured by comparing the coordinates of the same GPS receiver over time. The coordinates are obtained using trilateration.
All materials I could ...
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How might 25% lower gravity affect precipitation on an Earth-like planet? [closed]
I'm working on a science fiction project and hoping someone who knows something about climate can answer this question for me: if Earth had 25% less gravity, how would that affect precipitation? I ...
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Expression for the gradient of gravity potential in spherical coordinates
I am currently using the GGM05C Stokes' coefficients to reconstruct the gradient of gravity potential of Earth.
I have found an expression for said gradient in spherical coordinates in this technical ...
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Why do ocean tides have negative and positive terms in their effects on Stoke's coefficients for calculating geopotential?
I have recently started working on calculating a Geopotential model based on GGM05C. In order to obtain a model as accurate as possible, some corrections must be applied to the normalized Stokes' ...
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What is the pressure at the center of the Earth?
In the question Does gravity increase the closer to the core you get?, it was determined that gravity reduces to zero at the center of the Earth. That is logical.
However if pressure is proportional ...
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Why does the moon orbit the earth and not the sun instead? [closed]
Objects orbit the sun because of the sun's gravity, and Earth's gravity is weaker than the sun's gravitational pull. So why does the moon orbit the Earth instead of the sun?
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