• sinkingship@mander.xyz
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    2 months ago

    I know you’re right, have read it elsewhere before. But I can’t figure out why that would happen. I doubt Earth is loosing mass. Does the moon slow down over time due to impacts or what causes this?

    • AEsheron@lemmy.world
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      2 months ago

      If it slowed down it would get closer, not further. The truth is, any orbit is only stable given a specific timeframe. The longer that timeframe, the less likely any given orbit is to remain. The moon has just a little bit more speed than the Earth can hold onto, so it is in an extremely slow escape, and always has been.

      • Jumuta@sh.itjust.works
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        2 months ago

        The moon has just a little bit more speed than the Earth can hold onto

        Unfortunately that’s not how orbital mechanics works :(

        If the moon had instantaneously more speed than the earth can hold onto (e.g. more centrifugal ‘force’ than balanced by the gravitational force), the moon will accelerate up, until the forces become balanced. This makes a elliptical orbit, like this:

        elliptical orbit gif

        Apparently the reason the moon is getting further away is that it’s gaining energy from earth’s tides

        anyway you should play ksp