Super blue moon is a simple astronomical phenomena. An orbit of the Moon around the Earth takes place once in 27.3 days but the period between two successive full moons is about 29.5 days. This difference happens because successive full moons take place at different points on a slightly elliptical orbit. In its dance around the earth, once in a while, a full moon occurs when the moon is at or near its closest approach, called the perigee point. When this happens, it is called a super-moon.