Why Does The Amount Of The Moon Illuminated Gradually Change Over 28 Days?

Why Does The Amount Of The Moon Illuminated Gradually Change Over 28 Days? The lunar phases gradually change over a synodic month (about 29.53 days) as the Moon’s orbital positions around Earth and Earth around the Sun shift. … Thus, this face’s sunlit portion can vary from 0% (at new moon) to 100% (at full