Question

What planets length of the day is 9 hours?

Answer 1

A Day On Jupiter: Given the fact that it is the largest planet in the Solar System, one would expect that a dayon Jupiter would last a long time. But as it turns out, a Jovian day is officially only 9 hours, 55 minutes and 30 seconds long, which means a singleday is just over a third the length of an Earth day.