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by aussieshibe 1341 days ago
Fair warning: everything I know about orbital mechanics is from Kerbal Space Program.

The moon cannot orbit at a higher speed while keeping the same semi-major axis (average distance to the orbital centre of mass).

If you suddenly doubled the orbital speed of the moon right now, the apoapsis (the highest point in its orbit relative to the orbital centre of mass) would increase significantly.

If you slowly accelerate the moon in the direction of its orbital velocity consistently over a long time period, the moon will slow down relative to the Earth, but it's semi major axis will increase.

Actual scientists of HN: have at me.

2 comments

> Fair warning: everything I know about orbital mechanics is from Kerbal Space Program.

Knowing what I know about that game I read this as: Warning; I actually know what I'm talking about here.

It depends; there's actually a mod that adds realistic n-body gravity, and it's remarkable how much it affects.
Yeah, the moon isn't "drifting away" on its own, its being forced away as it takes energy from the Earth.