Susan L. Norwood
The Moon's Rotation
Objective: To have the students understand why we only see one side of the moon as it rotates on its axis.
Materials: Students, one small (tennis size) ball with a marked spot on it.
Procedure: Have each student try this exercise and observe others as they do the exercise. Have the student imagine that he is the earth. Have the student hold out one hand and hold the ball , (the moon) with the marked side visible to him. Have the student turn around slowly. Have the student notice that the mark on the ball has been visible to the student (earth) at all times as it made a complete rotation. This is what the moon does during a month's time period. Have the students try this again but this time keeping the marked spot on the ball facing the in the same direction at all times. If this were what actually occurred, then we would see the other side of the moon.
The moon changes its appearance regularly each month. The bright shape that we see from earth lit by the sun is called the moon's phase. The phases change as the moon orbits around the earth. Depending on where the moon is in its orbit around the earth, sunlight will be coming from the right , the left, different angles, and from behind the moon itself. The reflected light that the moon gives off allows us to view the various phases of the moon with an unaided eye.
