Motions of the Planets - Motions of the Planets With your...

Motions of the Planets
With your unaided eyes (that means without using binoculars or a telescope) you can see six
planets (can you name them all?). How can you tell that an object in the sky is a planet and not a
star? I'll tell you after I go over the motions of the planets (yes, I do like to keep my students in
suspense!).
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Like pretty much everything else, planets rise somewhere in the East and set somewhere
in the West. The path they appear to follow is pretty close to the path that the Sun and
Moon appear to follow.
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Not all planets move in the same way. Some are only seen near the Sun, either around the
time of sunrise or sunset ( Mercury and Venus are the two that do this - in the animation,
the Sun is the yellow dot, Mercury is the red dot, and Venus is the bluish dot. The stars
have been removed to show the motion clearly). This causes people to sometimes call
them the Morning or Evening Stars. This is particularly true of Venus, which is the
brightest thing up in the sky after the Sun and the Moon.