Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has the longest rotation period (243 days) of any planet in the Solar System and rotates in the opposite direction to most other planets. Only Uranus and Venus rotate clockwise on their axes whereas the other planets rotate counterclockwise or anticlockwise. A possible theory to explain the differences in rotation is that both Venus and Uranus in their formation history had counterclockwise rotation until a gigantic impact led to its change in rotation.

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