The most luminous object in our sky is the moon, especially at night. The moon has no light of its own, but shines by sunlight reflecting from its surface. The moon orbits the Earth, which takes appoximately 29 days to completley circle. There are eight phases of how the moon appears, principal and intermediate. NEW MOON, WAXING CRESCENT, FIRST QUARTER, WAXING GIBBOUS, FULL MOON, WANING GIBBOUS, THIRD OR LAST QUARTER, and WANING CRESCENT. The new, first, full, and third quarters are considered the principal phases, each principal phase is approximately 7 days. The time of year will also affect how the moon looks to the eye.
Some definitions of the moon phases… Waxing is when the surface of the moon is increasing. Waning is when the illuminated surface is decreasing. Gibbous refers to when 51-99% of the moon surface is visible in the sky, while a crescent is less than 50% visible. Waxing gibbous is the intermediate phase between the full moon and first quarter moon. Waxing crescent is the intermediate phase between first quarter and new moon. Waning crescent is between new moon and last/third quarter moon, while waning gibboous is between last/third quarter and full moon. A new moon is almost invisible to the eye, this when the moon is closest to the sun. A full moon is a completley illuminated disc. A supermoon is a full moon that is as close to the Earth as it will ever get. A supermoon appears much larger than the moon on a regular day. A total lunar eclipse occurs when the moon passes directly into the Earth’s shadow.