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If the earth suddenly became a point mass except for all the humans, we'd all already be in orbit. At the "top" of a highly elliptical orbit that passes relatively close to that point mass, yes, but an orbit. Everything that was within the Earth's sphere of influence, not moving so fast to be on an escape trajectory, and not with 0 horizontal velocity relative to the point mass would be in an orbit.

Orbital means "on a trajectory that doesn't intersect (or escape from) the body you are orbiting", otherwise the word is meaningless.




A person standing at the north pole wouldn't be in orbit. They would fall directly down.

(Wouldn't they?)


I think it would also have to be at an equinox. Otherwise the pole would be tilted towards or away from the sun, meaning that it orbits at a slightly different velocity, so you would have some velocity relative to the center of mass.


I concur. Right up until they exhaled and gave themselves a little horizontal velocity.




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