What is the rotation of Mars, Mercury, Venus, and Earth?Rotation ( Program or retrograde
Be careful to understand the difference between a planet's rotation, orbit, and retrograde motion. These are different things. If you look down on the solar system from the direction of the North Star, you'd see that all major planets in the same plane orbiting the sun counterclockwise, and each rotating on its axis counterclockwise, with the exception of Uranus, which rotates on its side, and Venus, which rotates clockwise, and whose ROTATION is sometimes referred to as "retrograde."
Retrograde MOTION, however, refers to a planet's apparent motion, or seemingly backward travel against the background of stars as seen from Earth. The planet isn't moving backwards, it's orbit and rotation do not change; what changes is that Earth, while orbiting the Sun, sometimes "catches up" and passes by another planet, so it looks like that planet is moving backwards.
The New Intelligent Man's Guide to Science, pg. 87, I. Asimov,1965
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The rotation of Mars is 687.
earth is 365 1/2
mercury is very slow in rotation and fastest in revolution.
venus is 243 days
243 - Mars
365 - Earth
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Venus has a retrograde rotation and rotates 243 times in one full orbit.
Mars in Retrograde happens the least frequently of any other planet in the solar system, but its duration is the longest of the personal planets (Mercury, Venus & Mars), being retrograde for approximately 2.5 months almost every 2 years.
Every four months, Mercury stations and turns retrograde, remaining so for approximately twenty-two days.
Earth, obviously, rotates 365 times in one orbit around the sun.