The surface of the moon has dents on it. They’re called craters! They were made when space rocks, called meteorites, crashed into it.

• Fill a tray with sand or flour. Don’t pack it down—the surface should be powdery, like the moon.
• Gather some marbles and balls of different sizes and weights.
• Drop them onto your moon surface.
• Do different balls and marbles make different kinds of craters?
• Does it make a difference if you drop the balls or marbles from different heights?
• Try predicting the size of crater you’ll make before you drop a ball. Were you right?