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The waxing moon.

At 20:36:52 UT Thursday 21 September 2017
the waxing moon’s phase is

3.02% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 20.6311111111111 in decimal hours.
The Julian date is 2458017.5301602.
The sun’s ecliptic longitude is 179.041390233636 degrees.
Its mean anomaly is 258.14730344261 degrees.
The moon’s true longitude is 559.04356487368 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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