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The waning moon.

At 18:37:43 UT Saturday 22 July 2017
the waning moon’s phase is

0.60% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 18.6452777777778 in decimal hours.
The Julian date is 2457956.50600472.
The sun’s ecliptic longitude is 120.119729142096 degrees.
Its mean anomaly is 197.94125922911 degrees.
The moon’s true longitude is 111.231106811471 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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