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The waning moon.

At 03:46:07 UT Tuesday 17 January 2017
the waning moon’s phase is

75.87% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 3.78527777777779 in decimal hours.
The Julian date is 2457771.25871238.
The sun’s ecliptic longitude is 297.232332719228 degrees.
Its mean anomaly is 14.00057095302 degrees.
The moon’s true longitude is 176.07266710059 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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