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At 00:01:27 UT Monday 21 August 2017
the waning moon’s phase was
is 0.0408333333333334 in decimal hours.
The Julian date was 2457986.50788509.
The sun’s ecliptic longitude was 148.12016673211 degrees.
Its mean anomaly was 226.74662069221 degrees.
The moon’s true longitude was 137.931243512472 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.)