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The full moon.

At 01:01:33 UT Wednesday 26 May 2021
the moon was


Some factors that go into this equation:

Universal Time is 1.0425 in decimal hours.
The Julian date was 2459361.49712164.
The sun’s ecliptic longitude was 65.039154977768 degrees.
Its mean anomaly was 141.067225455 degrees.
The moon’s mean longitude on 00 January 1990 was 318.351648 degrees.

These calculations incorporate the switch to the English New Style (N.S.)—i.e., Gregorian— calendar after Wednesday, 02 September 1752; the next day became Thursday, 14 September, skipping eleven days. (Please also note that, while fairly accurate, these calculations remain a bit buggy.)

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