SME
Grade 8 Science · Problem type
Why the moon changes shape
Use this for “Why does the moon look like a crescent some nights and a full circle on others?”
Explore
The moon is between Earth and the sun.
Its lit half faces away, and it crosses the sky in the daytime, so we see nothing.
Assumptions
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The moon makes no light; we see the half the sun lights.
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As the moon goes round Earth in about a month, we see more or less of its lit half.
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Seen from the Northern Hemisphere, a waxing moon grows, lit on the right; a waning one shrinks, lit on the left.
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