To look up the phase of the moon for any date,
just fill out the form below, then hit "Find Phase."

The new moon.

At 07:39:09 UT Thursday 25 May 2017
the moon’s phase was


Time Zone:   

Some factors that go into this equation:

Universal Time is 7.66916666666666 in decimal hours.
The Julian date was 2457898.5040342.
The sun’s ecliptic longitude was 64.314118648472 degrees.
Its mean anomaly was 140.32293860448 degrees.
The moon’s true longitude was 57.0308900538668 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.)

 Send comments to

© 1997–2018 by 3IP.