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The waxing moon.

At 21:24:21 UT Wednesday 20 September 2017
the waxing moon’s phase was

0.53% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 21.4225 in decimal hours.
The Julian date was 2458016.50528188.
The sun’s ecliptic longitude was 178.095047081757 degrees.
Its mean anomaly was 257.19415735154 degrees.
The moon’s true longitude was 546.430508281206 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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