The length of the day on each planet is indicated by the following table, which shows the length of time required for revolution on its axis.

Planet.

Daily revolution in hours, minutes and seconds.

Mars...

24 h. 39 m. 2 1/2 s.

Mercury...

24 h. 5 m. 28 s.

Venus .....

23 h. 21 m. 7 s.

Earth...

24 h.

Saturn .....

10 1/2 h.

Jupiter .....

9 h. 56 m.

Uranus .....

. 7 h. 5 m.

The sun revolves upon its own axis at the rate of 4,564 miles per hour, and yet requires 25 1/2 days to complete one entire revolution.