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The waning moon.

At 02:51:52 UT Wednesday 18 January 2017
the waning moon’s phase is

67.19% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 2.8811111111111 in decimal hours.
The Julian date is 2457772.17193302.
The sun’s ecliptic longitude is 298.211545478326 degrees.
Its mean anomaly is 14.94908541421 degrees.
The moon’s true longitude is 188.098957327998 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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