1. Constellations and Planets in the Night Sky Created for TCSS

3. Stars are trillions of kilometers away, far outside the solar system. Even as the Earth moves through its orbit around the Sun, each star remains nearly the same distance away.

5. Planets are closer to us than stars and they are in constant motion as they move around, or orbit, the sun. Because of this, they can be seem in different locations in the night sky in relation to the constellations.

6. If you observed the planet Mars every night for a while, at first it would appear to move from west to east among the stars. Then it would reverse direction for a while and travel from east to west. Finally, it would once again move in a eastward direction. This is why the Greeks called planets wanderers.

7. Movement of Mars across the sky over about a two month period in 2005