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The waning moon.

At 08:27:57 UT Thursday 23 May 2019
the waning moon’s phase is

79.85% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 8.4825 in decimal hours.
The Julian date is 2458627.29851689.
The sun’s ecliptic longitude is 61.959829660402 degrees.
Its mean anomaly is 137.9076165477 degrees.
The moon’s mean longitude is 318.351648 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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