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If a planet would spin faster , would it have a lower gravity pull?


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If I'm not mistaken, I think KSP actually emulates the centrifugal force on the surface of a planet. Experimentation will certainly be done when we make the rest of the solar system in <INSERT TIME>

Well it pretty much would have to be taking into account the rotation, otherwise the advice to always launch toward the east wouldn't matter.

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As an example, the Earth rotates at 465 m/s at the equator. This translates into a centrifugal force of 0.03 m/s^2, or 0.003 g's. So if the Earth were not rotating, you would feel 0.3% heavier at the equator.

Jupiter rotates at 12600 m/s at the equator, which is a force of 2.3 m/s^2, or 0.23 g's. Considering the gravity on Jupiter is 2.4 g's, if Jupiter were not rotating, you would feel 10% heavier at its equator.

Saturn is an even better case, the centrifugal force at the equator is 20% of the planet's gravity. This is why Saturn appears noticeably squashed in photos.

On the dwarf planet Haumea you would feel 14 times heavier on the poles than on the equator.

Thanks, this is a really good answer.

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Then it's spinning at 2.82m/s. If some speed is 2m/s bellow orbital and 4m/s bellow escape, escape velocity is 2m/s higher than orbital. But escape velocity is always square root of 2 times higher than orbital. This is entirely possible for a tiny moon.

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Unless that mass was rigid with great tensile strength. Like whatever Kerbalnauts build station docking ports out of. A planet made of that would never spin apart.

Or you could build it out of tightly packed neutrons. Apparently entire neutron stars can rotate several hundred times per second and not break apart...

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Apparently entire neutron stars can rotate several hundred times per second and not break apart...

Yes.

But, neutron stars are also really small, so the centripetal force is correspondingly less. Also, they are really dense, so gravity is correspondingly much, much stronger. If I recall, the spin rate required to overcome gravity for the average neutron star is something like a few thousand Hertz. Even the millisecond pulsars don't come close to that.

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If I'm not mistaken, I think KSP actually emulates the centrifugal force on the surface of a planet. Experimentation will certainly be done when we make the rest of the solar system in <INSERT TIME>

Harv already checked that when he first gave a spin to Kerbin - I remember a screenshot with day length set to about 30 minutes and stuff flying off the space center by itself :)

Seeing Mesklin quoted on the first page is nice: anime fans might also remember Hecatonchires, the prison planet from Outlaw Star.

And yeah, we need something like these somewhere in the system ;)

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