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The new moon.

At 12:13:35 UT Monday 21 August 2017
the moon’s phase was


Time Zone:   

Some factors that go into this equation:

Universal Time is 12.2430555555556 in decimal hours.
The Julian date was 2457986.5001.
The sun’s ecliptic longitude was 148.609870868866 degrees.
Its mean anomaly was 227.24774936199 degrees.
The moon’s true longitude was 145.200936329861 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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