Planetary Motions

In their apparent motions across our sky, the planets behave somewhat like the Sun, but their motions are more complex.

Therefore, as viewed from Earth, the planets move at different speeds among the stars. Remind yourself about our view of the planets.

Periods of transversing the Zodiac (remember that we are moving too!):

Mercury 1 year
Venus 1 year
Mars 687 days
Jupiter 12 years
Saturn 29 years

Because the planets are all moving in their orbits at the same time we are, their positions in our sky are constantly changing.


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