The moon Phoebe orbits Saturn in a retrograde direction.Many other minor moons of Jupiter orbit retrograde. The moons Ananke, Carme, Pasiphae and Sinope all orbit Jupiter in a retrograde direction.Venus rotates slowly in the retrograde direction.Some significant examples of retrograde motion in the solar system: Retrogradation puzzled ancient astronomers, and was one reason why they named these bodies ‘planets’ which in Greek means ‘wanderers.’ In the geocentric model of the solar system, this motion was accounted for by having the planets travel in deferents and epicycles. The period between such retrogradations is the synodic period of the planet. The more distant outer planets retrograde more frequently. Mars goes through retrogradation about every 22.5 months. Finally as Earth swings past the the planet in its orbit, it appears to resume its normal west-to-east drift on successive nights. This is retrogradation, since the planet seems to be moving in a opposite direction to typical direction for planets. When this occurs, the planet we are passing will first appear to stop its eastward drift, and it will then appear to drift back toward the west. However, since Earth completes its orbit in a shorter period of time than these outer planets, we occasionally overtake an outer planet, like a faster car on a multiple-lane highway. This motion is normal for these planets, so its name is a direct motion (not retrograde). Though these planets appear to move from east to west on a nightly basis in response to the spin of Earth, they are most of the time drifting slowly eastward with respect to the background of stars. The latter term is used in reference to the motion of the outer planets (Mars, Jupiter, Saturn, and so forth). Retrograde motion should not be confused with retrogradation. These retrograde satellites can be seen in the sky going westward. There are also artificial satellites that orbit clockwise as seen from the pole star. However, since the space shuttle and satellites that are moving eastward would appear from Polaris to be orbiting the Earth counterclockwise, they are considered direct satellites. This orbit also may be considered retrograde motion.

However, it is possible to observe a body moving west to east, such as an artificial satellite or space shuttle. The motion of most bodies in the sky is from east to west. When we observe the sky, we expect most objects to move in a particular direction with the time. Some comets and small asteroids orbit the Sun in retrograde orbits. Some small moons orbit clockwise around their planet, and are called retrograde satellites. Venus and Uranus spin clockwise, so they have a retrograde rotation. Rotation in the opposite sense is called retrograde.

Retrograde motion of planets