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At 20:40:03 UT Thursday 21 September 2017
the waxing moon’s phase is
is 20.6841666666667 in decimal hours.
The Julian date is 2458017.53023886.
The sun’s ecliptic longitude is 179.04355419501 degrees.
Its mean anomaly is 258.14948236216 degrees.
The moon’s true longitude is 559.072065027962 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.)