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

The waxing moon.

At 11:29:42 UT Saturday 27 May 2017
the waxing moon’s phase is

4.18% full

Time Zone:   

Some factors that go into this equation:

Universal Time is 11.5116666666667 in decimal hours.
The Julian date is 2457900.54183125.
The sun’s ecliptic longitude is 66.387613779675 degrees.
Its mean anomaly is 142.45203956591 degrees.
The moon’s true longitude is 89.9912240175266 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

© 1997–2017 by 3IP.