Grade 6 · Science · Lesson 29

Sun-Earth-Moon System Models

Look up at the night sky for one whole month and the Moon will look different almost every night. Sometimes it is a thin curve. Sometimes it is a big bright circle. Sometimes you cannot see it at all. The Moon is not changing shape — we are simply seeing different parts of it as it travels around Earth, and as Earth travels around the Sun. This is the Sun-Earth-Moon system.

What this lesson teaches

1Describe how Earth orbits the Sun and the Moon orbits Earth
2Order the eight phases of the Moon in the correct cycle
3Match each Moon phase shape with its name
4Explain why we see different Moon phases from Earth

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