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Hello to all,

For those of us who keep indulging in watching the sky, right to-day by 06h38m UT the Moon declination reaches its maximum southerly value at -28°43.5' .

First time since 1950 Sept. 19 , and not until maybe 2062 at the earliest.

An interesting and concise explanation of this well-known regular 18.61 year interval phenomenon is given here:

https://adsabs.harvard.edu/full/1972JBAA...82..192K (pages 192 and 193) by G.P. Können & Jean Meeus.

Our so dear Mr Jean Meeus aced it again here !

Note : Brown's Moon Theory/Ephemeris was completed in 1908. After it was slightly amended by Eckert (starting with the Improved Lunar Ephemeris (I.L.E.), 1952), it has been likely used under its final form I.L.E. j=2 (Brown / Spencer Jones / Eckert, 1972) to compute the Moon declinations published in this paper.

For 06h39 E.T. on March 22nd, 2025 I.L.E. j=2 yields: Moon Declination = -28°43.32" .

Quite an achievement then if we compare its results to one of the very the best current numerical integrations available to-day (Here INPOP 2019 from IMCCE / Bureau des Longitudes in Paris) :

2025-03-22T06:38:599:999 17:58:00.2036 -28°43'32.427"

Kermit