From a given latitude on Earth, is it possible to calculate the number of days in a year when there is a wet moon , that is when the moon is lit on the bottom?

If, for example, I want to do the calculation for the year 2023, how should I go about this? And can I predict those days as well?

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    $\begingroup$ This post describes how to calculate it: astronomy.stackexchange.com/questions/39152/… $\endgroup$
    – JohnHoltz
    Jan 14, 2023 at 2:52
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    $\begingroup$ Meeus covered this topic in one of the "Morsels" books, though I believe he called it a "moon as a boat". He did not show how to calculate it, but showed the results of where it could happen and how often. $\endgroup$ Jan 14, 2023 at 21:41


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