Phases of the Moon
Earth and Space

Phases of the Moon: demonstration

Practical Activity for 11-14 IOP RESOURCES

A small white ball and light source are used to show how the phases of the Moon are created from the point of view of the Earth.

Apparatus and Materials

  • Small polystyrene or ping pong ball
  • A stick to which the ball can be attached
  • 3 lamps with card cylinders attached

Health & Safety and Technical Notes

Read our standard health & safety guidance


Teaching Notes

  • Although you can try this demonstration with a single lamp, the phases appear more defined if 3 lamps are used with their light directed towards the “Moon” using cardboard cylinders.
  • The lamps should be placed at least 2 metres from where the Earth-Moon system will be.
  • In this demonstration a student (Earth) sat on a computer chair that allowed them to rotate their position so that they always faced the Moon (white ball) as the Moon orbited the Earth.
  • The phases are quite convincing, and could be photographed or shown to the rest of the class using a webcam connected to a computer and projector.
  • You can use a similar set up to demonstrate Solar Eclipses.

Phases of the Moon
can be exhibited by Moon
IOP DOMAINS Physics CPD programme

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