The rotation period of an astronomical object is the time that it takes to complete one revolution around its axis of rotation relative to the background stars. It differs from the planet's solar day, which includes an extra fractional rotation needed to accommodate the portion of the planet's orbital period during one day.
Read more about Rotation Period: Measuring Rotation, Earth, Rotation Period of Selected Objects
Famous quotes containing the words rotation and/or period:
“The lazy manage to keep up with the earth’s rotation just as well as the industrious.”
—Mason Cooley (b. 1927)
“There is a period near the beginning of every man’s life when he has little to cling to except his unmanageable dream, little to support him except good health, and nowhere to go but all over the place.”
—E.B. (Elwyn Brooks)