Figure 2-14: The Ecliptic Plane and the Ecliptic (a) The ecliptic plane is the plane in which Earth moves around the Sun. (b) As seen from Earth, the Sun appears to move around the celestial sphere along a circular path called the ecliptic. Earth takes a year to complete one orbit around the Sun, so as seen by us the Sun takes a year to make a complete trip around the ecliptic.