To look up the phase of the moon for any date,
just fill out the form below, then hit "Find Phase."
At 04:19:21 UT Monday 18 December 2017
the moon’s phase was
is 4.33916666666666 in decimal hours.
The Julian date was 2458105.5001.
The sun’s ecliptic longitude was 266.462630707602 degrees.
Its mean anomaly was 344.2151828058 degrees.
The moon’s mean longitude was 318.351648 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.)