ELI5: Explain Like I'm 5

Moon

The moon is a big rock in the sky that goes around Earth. It's the only natural satellite (a big rock that goes around a planet) that Earth has. The moon is made out of rocks and dust and it reflects the sun's light so we get to see it in the night sky. The shape of the moon changes as it goes around Earth, so sometimes it's a big circle, and sometimes it's just a sliver.
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