Solar and sidereal days
The following diagrams explain
the difference between a solar day (based on the Sun) and a sidereal day (based on
the stars).
![](images/1.png)
The stars rise 3m 56s earlier each night compared with solar time. This is due to the motion of the Earth in its orbit round the Sun.
![](images/2.png)
Solar day. The Earth makes one rotation compared with the Sun.
3 minutes 56 seconds longer than a sidereal day.
Sidereal day. The Earth makes one rotation compared with the distant stars. 3 minutes 56 seconds shorter than a solar day
schoolphysics solar and sidereal time animation
To see an animation of the motion of solar and sidereal time click on the animation link.
A VERSION IN WORD IS AVAILABLE ON THE SCHOOLPHYSICS USB