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    Re: The Three-body Problem
    From: John Clements
    Date: 2021 Oct 25, 18:41 -0700

    This is probably obvious, but I'll say it anyway:

    1) The second does not evenly divide the time taken by the earth's rotation. That's why we need leap seconds.

    2) The time taken by the earth's rotation does not evenly divide the time taken by an orbit around the sun. That's why we need leap days.

    3) The moon's orbit does not evenly divide the time taken by an orbit around the sun. We just gave up on that one :)

    In each case, we have two independent units of time that don't divide each other. If the earth's orbit were to slow down, without changing its rotational speed, we would need leap days, rather than leap seconds.

    John

       
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