Original: The reason for this apparent misadjustment of our clocks is that the Sun is not standing still on the celestial sphere , as the stars do , but moves about 1 Â per day eastwards over a great circle known as the ecliptic ( which is 360 Â or a full circle in one year , the annual motion of the Sun ) .
Simplified: The reason for this is that the Sun does not stand still on the celestial sphere , and the stars do . The sun moves about 1 Â per day eastwards over a great circle known as the ecliptic ( which is 360 Â or a full circle in one year , the annual motion of the Sun ) .