September 10 Waxing Gibbous 99% |
September 11 Full Moon 100% |
September 12 Waning Gibbous Illumination: 99% |
September 13 Waning Gibbous 97% |
September 14 Waning Gibbous 93% |
On this day the Moon was in a Waning Gibbous. During this phase the Moon can be seen in the early morning daylight hours on the western horizon. This is the first phase after the Full Moon occurs. It lasts roughly 7 days with the Moon’s illumination growing smaller each day until the Moon becomes a Last Quarter Moon with an illumination of 50%. The average Moon rise for this phase is between 9pm and Midnight depending on the age of the phase. The moon rises later and later each night setting after sunrise in the morning.
Visit the September 1878 Moon Phases Calendar to see all the daily moon phase for this month.
The Waning Gibbous on September 12 has an illumination of 99%. This is the percentage of the Moon illuminated by the Sun. The illumination is constantly changing and can vary up to 10% a day. On September 12 the Moon is 15.53 days old. This refers to how many days it has been since the last New Moon. It takes 29.53 days for the Moon to orbit the Earth and go through the lunar cycle of all 8 Moon phases.
There are 8 lunar phases the Moon goes through in its 29.53 days lunar cycle. The 4 major Moon phases are Full Moon, New Moon, First Quarter and Last Quarter. Between these major phases, there are 4 minor ones: the Waxing Crescent, Waxing Gibbous, Waning Gibbous and Waning Crescent. For more info on the Moon Cycle and on each phase check out Wikipedia Lunar Phase page.
Check the weather before a night of Moon gazing at weather.com
For a list of all the current meteor showers visit American Meteor Society