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Notes on the Earth, Sun and Moon - how they affect each other

 Chapter 1-3

pages 20-29

EQ: How do the Earth, Sun and Moon affect each other?


  • The movement of the Earth and moon in their orbits affect the appearance of moon by blocking different amount of light from the sun


1) What are the phases of the moon?

  • The revolution of the moon around the earth causes it to appear to change shape
  • The moon goes through all phases in 29.5 days (its period of revolution)
  • The moon does not have light, it just reflects the sunís light
  • When the moon comes between the earth and the sun, we are in the new moon phase (we see total darkness)
  • Earthshine is reflected sunlight on the moon by the Earth.
  • As the moon travels from the new moon (day 1 to about day 14) the amount of the moon we see grows larger (it is waxing)
  • From about day 15 in the orbit (the Full Moon) we begin to see less and less of the moon (it is waning)


Poem to help you remember waxing and waning:

As we travel with more light, the waxing moon is on the right.

When the light gets less and less, the waning moon is on the left.






Text Box: Key: The white is the part of the moon that you see














Do you know your moon phases?

Quiz yourself with these Moon Phase Flash Cards!



What is an Eclipse?

  • When the Earth and moon revolve around the sun they sometimes block out the sunlight and cast a shadow on the other body.
  • The shadow causes an eclipse
  • Two types, depend on which body is blocked (in shadow)
  • Solar Eclipse- When the moon blocks the sunlight from the earth (Earth is in the moonís shadow)
  • During a solar eclipse- never look at the sun!
  • Lunar Eclipse- When the Earth blocks the sunlight from the moon (Moon is in Earthís shadow)
  • The shadows have two parts:
  • Umbra- The small, dark inner shadow
  • Penumbra- The larger, lighter outer shadow




Text Box: Lunar Eclipse
Text Box: Umbra
Text Box: Penumbra
Text Box: Penumbra
Text Box: Penumbra
Text Box: Penumbra
Text Box: Umbra
Text Box: Solar Eclipse
















3) What are tides and how are they caused?