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)
“In a period of a people’s life that bears the designation “transitional,” the task of a thinking individual, of a sincere citizen of his country, is to go forward, despite the dirt and difficulty of the path, to go forward without losing from view even for a moment those fundamental ideals on which the entire existence of the society to which he belongs is built.”
—Ivan Sergeevich Turgenev (1818–1883)