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At 17:20:17 UT Wednesday 31 January 2018
the moon’s phase was
is 17.3547222222222 in decimal hours.
The Julian date was 2458150.49960305.
The sun’s ecliptic longitude was 311.789223403714 degrees.
Its mean anomaly was 28.1181976504 degrees.
The moon’s true longitude was 2294.07240779305 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.)