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The full moon.

At 22:52:25 UT Wednesday 31 January 2018
the moon’s phase was


Time Zone:   

Some factors that go into this equation:

Universal Time is 22.8902777777778 in decimal hours.
The Julian date was 2458150.49769775.
The sun’s ecliptic longitude was 312.023256155773 degrees.
Its mean anomaly was 28.3455353879 degrees.
The moon’s true longitude was 2297.52364482839 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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