The gravity of the earth or more specifically the gravitational acceleration, $g$, is the acceleration objects with mass experience toward the earth due to gravity.

How much does this vary according to where the moon is, if at all?

In particular what approximate values for $g$ do we get for standing under the moon and for when the moon is directly under our feet (on the opposite side of the earth)?

How do these compare with $g_0$?

Why, and as a bonus softer question: what are the consequences of this?

  • 2
    $\begingroup$ Did you try to do a back-of-an-envelope-calculation? $\endgroup$
    – Qmechanic
    Jun 17 '20 at 13:44
  • $\begingroup$ Try to put a heavy book (about 3 kg) in a kitchen scale that has a precision of 1 g in 2 situations: at midnight and at noon with a new Moon. So you have the combined gravitational efect of Sun and Moon, that a scale like that can measure. Maybe you will be surprised by the outcome... $\endgroup$ Jun 17 '20 at 18:49
  • $\begingroup$ There is barely any difference in $g$ between when the Moon is directly overhead vs directly underfoot. There is a much bigger difference between when the moon is directly overhead (or directly underfoot) versus on the horizon. $\endgroup$ Jun 17 '20 at 22:13

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