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This image compares the retrograde rotation of Venus to the direct rotation of Earth.
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Windows original, courtesy of Nate Proulx

What are the retrograde motions of planets in the sky?

It depends on which type of motion you are asking about. If you take a birds-eye view from the top of the solar system all the planets orbit around the Sun in a counter-clockwise (or direct) direction. Most planets also rotate counter-clockwise, so that the Sun rises in the east and sets in the west. A few rotate in the opposite direction, so that the Sun rises in the west. This is known as retrograde motion.

The planets with retrograde rotations are Venus, Uranus, and Pluto. Venus' orbit is clearly retrograde. Scientists debate whether Uranus' orbit is truly retrograde. Uranus is tilted on its axis at nearly a right angle (so that its poles and not its equator point towards the Sun). Depending on what pole is classified as its north pole Uranus's rotation could be either direct or retrograde.


Submitted by Kyle (Canada)
(June 17, 1999)

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