We all know that the earth and other planets in the solar system revolve around the sun. Each planet rotates in two ways , one on its own axis , which is called ecliptic motion. Day and night are due to this diurnal motion of the earth. In addition, the earth revolves around the sun. This rotation is called the annual motion of the earth. It takes 365 days and 6 hours for the earth to revolve around the sun. This period is called one year or one solar year. The seasons change because of this annual movement of the earth.