Super Full Moon on 03-December-2017 What is Full Moon? Based on Wikipedia: A full moon is the lunar phase that occurs when the Moon is completely illuminated as seen from Earth. This occurs when Earth is located directly between the Sun and the Moon (more exactly, when the ecliptic longitudes of the Sun and Moon differ by 180 degrees). This means that the hemisphere of the Moon that is facing Earth (the near side) is almost fully illuminated by the Sun and appears round (while the far side is almost completely unlit). A full moon occurs every once a month. When the full moon moves into Earth's shadow, a lunar eclipse occurs, and all or part of the Moon's face may appear reddish due to the Rayleigh scattering of blue light in Earth's atmosphere. Lunar eclipses can occur only at full moon, where the Moon's orbit allows it to pass through Earth's shadow. Lunar eclipses do not occur every month because the Moon usually passes above or below Earth's shadow, whic...