Solar Light Demonstration

Materials:
Large flashlight
Basketball (Earth)
Tennis (Moon)
Solid rod of wood or metal

Procedure:
Attach the tennis ball to the solid rod to increase ease of movement.
One student holds Earth, slanted on its axis.
Another student holds the Moon, revolving around Earth.
Another student is responsible for shining the Sun.

Day and Night:

• Turn off the lights to the classroom, and turn on the flashlight to represent the Sun shining on Earth.
• Pick a spot on the Earth to be where the classroom is. The student holding Earth rotates Earth about its axis (ignore the revolution about the sun). Note how the chosen point enters phases of light and dark as the Earth rotates.
  Solar Eclipse:
• Have the student holding the Moon position the moon such that it is blocking the Sun's light from reaching the Earth.
• Explain that, although the Earth is much bigger than the Moon, the distance between the Moon and Earth allow the Moon to entirely block out the Sun's rays.
• Also explain that, since the Earth is rapidly rotating, the eclipse lasts only a short amount of time, and that, after the eclipse, the moon begins to unblock the Sun.
• Explain that, because of the complex 3-dimensional revolution of the Moon around the Earth, such an occurrence is very rare.
  

Moon and Lunar Eclipse:

• Place the marked "classroom" spot on Earth facing away from the Sun, such that it is nighttime.
• Have the student holding the Moon place it in front of the Earth, in the same way done during the Solar Eclipse demonstration.
• Note that ½ of the Moon is lit by the Sun, but the "classroom" cannot see any light being reflected by the Moon. This is a New Moon.
• Have the student holding the Moon then place it on either side of the Earth. Also note that ½ of the Moon is still lit by the Sun, but the "classroom" can only see ½ of the lit section, and thus it is a Quarter Moon.
• Have the student with the Moon hold it above and behind the Earth, such that light from the flashlight can be seen on ½ of the Moon. Explain that, under normal circumstances, this would be a full moon, as the "classroom" can see exactly ½ of the Moon's surface
• Then, have the student holding the Moon lower it directly behind the Earth. Show that, during this configuration, the Earth entirely blocks out the Sun's rays from the Earth, and the light reflecting on the moon is reduced to nothing.
• Explain that, because of the complex 3-dimensional revolution of the Moon around the Earth, such an occurrence is very rare.