Earth natural satellite

The Moon is our only natural satellite. The young Earth had no moon, but soon after the Earth formed, a Mars-sized rogue planet struck it a huge glancing blow. A large chunk of Earth and most of the rogue planet were vaporized into a cloud that rose more than 22,000km in altitude, where it condensed gradually into the solid moon.Looking down from the north pole we would see the Moon orbiting counterclockwise from west to east. Neil Armstrong took that historical step of "one small step for man one giant step for mankind".The diameter of the moon is 2,160 miles. The Moon takes about 27 days, 7 hours, 43 minutes, 11.6 seconds to go all the way around the Earth and return to its starting position. The U.S.S.R. had made the opening gambit, sending the first artificial satellites into orbit, starting with the 83.5-kilogram Sputnik I in October 1957. Most planets are named for Roman gods but moons are named for Greek gods.The moon is slowly moving away from Earth. The current distance between the Earth and the moon is 384,000km but it was closer in the past.