Our moon is the fifth largest of the 190+ moons orbiting planets in our solar system. Earth's only natural satellite is simply called "the Moon" because people didn't know other moons existed until Galileo Galilei discovered four moons orbiting Jupiter in 1610. It also causes tides, creating a rhythm that has guided humans for thousands of years. The Moon was likely formed after a Mars-sized body collided with Earth.
urn:nasa:pds:context:target:satellite.earth.moon
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