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The full moon.

At 22:24:40 UT Saturday 18 May 2019
the moon was



Some factors that go into this equation:

Universal Time is 22.4277777777778 in decimal hours.
The Julian date was 2458622.49997601.
The sun’s ecliptic longitude was 57.708530413521 degrees.
Its mean anomaly was 133.5520933564 degrees.
The moon’s mean longitude 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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