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The Elusive Planet

Time for One Rotation About its Axis

Mercury rotates about its axis as it travels in its orbit about the Sun. The time for one complete rotation (with respect to the stars) is about 59 Earth days – exactly 2/3 of the time it takes for Mercury to complete one orbit around the Sun.

A Day on Mercury animation screenshot

Take a look at the "Orbit Rotation" animation to see these motions together. Click on the image above

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