Topic summary
Sidereal day
Extracted from the Wikipedia article Sidereal time.
Sidereal days compared to solar days on other planets
Six of the eight solar planets have prograde rotation—that is, they rotate more than once per year in the same direction as they orbit the Sun, so the Sun rises in the east. Venus and Uranus, however, have retrograde rotation. For prograde rotation, the formula relating the lengths of the sidereal and solar days is: