If we could stand outside the solar system and look down upon it from
above the north pole of the Sun (or the Earth), we would see that
nearly all the bodies in the solar system have motions that are
anticlockwise.Most of the planets rotate about their own axes in an anticlockwise
direction. This is called prograde rotation. Venus and Neptune are
exceptions. Venus has a very slow clockwise rotation (termed
retrograde), and Uranus, although it rotates every 15.5 hours, has its
equator inclined at almost a right angle to its orbital plane. It is thus
difficult to know whether to describe the rotation of Uranus as
prograde with an equatorial inclination of 98o or
retrograde with an inclination of 82o.
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