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The full moon.

At 10:55:30 UT Wednesday 31 January 2018
the moon’s phase was


Time Zone:   

Some factors that go into this equation:

Universal Time is 10.9416666666667 in decimal hours.
The Julian date was 2458150.49983829.
The sun’s ecliptic longitude was 311.518073861589 degrees.
Its mean anomaly was 27.8548221815 degrees.
The moon’s true longitude was 2290.06079730092 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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