Astronomy: Moon Phases

by Janice VanCleave

moon gwche 1Studying the phases of the Moon is one of the easiest science projects. Instead of identifying the different phases, I want to introduce another objective.

First of all, I am working on a format that is comfortable for me, so don’t be surprised if my articles have different looks.


1. From Earth, the side of the Moon facing Earth is always the same.

2. In the Northern Hemisphere, you face south to view the Moon. (Which way would you face in the Southern Hemisphere? Why?)

3. The Moon rises and sets each day in about the same place on the horizon as does the Sun.

4. The boundary between the light and dark regions of the Moon is called the Terminator.

5. A lunar month is the time for the Moon to complete one cycle phase changes. This is about 29 days.

6. A waxing Moon is getting larger. This means the lighted area in increasing.

7. A waning Moon is getting smaller. This means the lighted area is decreasing.


1. Which way does the terminator move during a waxing Moon?

2. Which way does the terminator move during a waning Moon?


1. You can study pictures of the Moon during a lunar month.

2. You can study the different shapes of the Moon during a lunar month. Make a diagram of how the Moon looks  two or more times each week. Spacing your observations is best. Monday, Wednesday, and Friday would work great.

Link for photo

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