Original Description:
Use the arrows on your control panel to change the path radius and speed for the moon and the planet. To move the sun, just click and drag it. Watch the revolutions and rotations, and notice how they change when you change the controls.
Put an X in the box next to Path to show the path of the planet as it travels.
What happens if the planet moves faster? Or if the moon has a larger radius? Change the settings and find out for yourself.