Scientist have finally figured out how long a day on Saturn is. This has been hard to determine for scientists for many decades because there is no solid surface with landmarks to track the rotation.
The answer though was hidden in Saturn’s rings The rings responded to vibrations from within Saturn that cause variations in the gravitational field. The rings though picked up on the vibrations.
Data from Voyager estimated the day to be 10 hours 39 minutes and 23 seconds, but the new data puts the day on Saturn at 10 hours, 33 minutes and 38 seconds.
You can find out more info at NASA.