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The waxing moon.

At 12:50:45 UT Thursday 27 July 2017
the waxing moon’s phase is

20.63% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 12.8625 in decimal hours.
The Julian date is 2457961.70630035.
The sun’s ecliptic longitude is 124.663449187595 degrees.
Its mean anomaly is 202.63200519314 degrees.
The moon’s true longitude is 178.690777099492 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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