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The new moon.

At 10:08:58 UT Wednesday 20 September 2017
the moon’s phase was


Time Zone:   

Some factors that go into this equation:

Universal Time is 10.1661111111111 in decimal hours.
The Julian date was 2458016.5001.
The sun’s ecliptic longitude was 177.636248224934 degrees.
Its mean anomaly was 256.73187277026 degrees.
The moon’s true longitude was 540.209736366463 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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