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At 02:39:43 UT Monday 21 August 2017
the waning moon’s phase will be
is 2.6786111111111 in decimal hours.
The Julian date will be 2457986.50577711.
The sun’s ecliptic longitude will be 148.226017944145 degrees.
Its mean anomaly will be 226.85495063776 degrees.
The moon’s true longitude will be 139.507817840374 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.)