Moon phases are measured in quarters. This month’s New Moon is on July 4 (nice darkness for fireworks) and the First Quarter is July 11, followed by the Full Moon on July 19 and the Third Quarter on July 26. That may seem a bit illogical in its order, and the names may seem off too because a quarter moon appears to us as a “half moon.”

The moon reaches its half-illuminated last quarter phase at the same instant worldwide, it occurs at different times by the clock, depending on one’s time zone.  A last quarter moon rises in the middle of the night and shines in the morning sky.

Although half-lit, it’s called a last quarter or third quarter moon because the moon is three-quarters of the way in its journey from new moon to new moon.


First Quarter Earth as it would be seen from space