Today the Moon will be in a Waxing Gibbous phase. This phase is when the moon is more than 50% illuminated but not yet a Full Moon. The phase lasts about 7 days with the moon becoming more illuminated each day until the Full Moon. During a Waxing Gibbous the moon rises in the east in mid-afternoon and is high in the eastern sky at sunset. The moon is then visible through most of the night sky setting a few hours before sunrise. The word Gibbous first appeared in the 14th century and has its roots in the Latin word “gibbosus” meaning humpbacked.
Visit the May 2021 Moon Phases Calendar to see all the daily moon phase for this month.
Today’s Waxing Gibbous Phase
The Waxing Gibbous on May 21 has an illumination of 68%. 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 May 21 the Moon is 9.13 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.
You can use this link to go forward or backward in time for Moon phase information. If you are curious you can even find out what phase the Moon was in when you or anyone else, you know was on the date the person was born.