I recall hearing, perhaps colloquially, that a centrifugal force doesn't exist. It can be mistakenly felt but, it is not a real force. Given this, how does the $L_2$ orbital point exist beyond the earth? The two major gravities are in, towards the system. What force is pulling outward, to counteract the Sun+Earth's gravity, and thus providing meta-stability to the $L_2$ point? Am I thinking about the forces incorrectly?
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4https://xkcd.com/123/ – PM 2Ring Feb 07 '22 at 14:37
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Our canonical question about centrifugal force is https://physics.stackexchange.com/q/109500/123208 Do you have a specific question that isn't covered by the answers there? – PM 2Ring Feb 07 '22 at 14:47
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1Related: How are the Lagrange points determined? – Qmechanic Feb 07 '22 at 16:21
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The thing about the Lagrange "point" is that it is not an actual point, i.e., there is not a single location in space where the orbiting satellite is fixed. Instead, the satellite is on a moving, circular orbit, which has the special characteristic of being at a fixed location relative to the Earth (which is also moving!).
In other words, the satellite is at a fixed point in space in the non-inertial frame where the Earth is also stationary. And since that frame is not inertial, you need to include "fictional" forces that do not actually "exist" in the inertial frame of the solar system.
Emilio Pisanty
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