Earth's Moon is the only place beyond Earth where humans have set foot. The brightest and largest object in our night sky, the Moon m akes Earth a more livable planet by moderating our home planet 's wobble on its axis, leading to a relatively stable climate. It also causes tides, creating a rhythm that has guided huma ns for thousands of years. The Moon was likely formed after a Mars-sized body collided with Earth. Earth's Moon is the fifth largest of the 200+ moons orbiting planets in our solar system. Earth's only natural satellite is simply called "the Moon" be cause people didn't know other moons existed until Galileo Ga lilei discovered four moons orbiting Jupiter in 1610. Scientists think the Moon was formed long, long ago when Earth crashed into a Mars-sized object Some ancient peoples believed the moon was a bowl of fire, while others thought it was a mirror that reflected Earth's lands and seas,