SMART 1 - ESA Lunar Orbiter Mission (2003)
Lunar Prospector - NASA Lunar Discovery Mission
Clementine - DoD/NASA Lunar Mapping Mission
Galileo - NASA Mission to Jupiter - Lunar Flyby
Apollo - NASA Lunar Manned Missions
Lunar Orbiter - NASA Lunar Mapping Missions
Surveyor - NASA Lunar Lander Missions
Ranger - NASA Lunar Impact Missions
Luna and Zond - Soviet Lunar Missions
Hiten - ISAS Lunar Flyby and Orbiter
AsiaSat 3/HGS-1 - Commercial Telecommunications Satellite
Earth and its Moon are relatively close in size, but the similarities end there
The Moon has no atmosphere and very weak gravity
Compared with the other moons in our solar system, our own Moon is something of an oddity. Except for tiny Pluto, all the other planets are much larger than their moons. But Earth is only about four times wider than its moon. Compared to huge planets like Jupiter and Saturn, which are 40 or 50 times larger than their biggest moons, Earth and its Moon could almost be considered twin planets.
The Earth may only have one Moon, but it's a big one! The Earth's Moon is the fifth largest in the whole solar system. But it is still smaller than the Earth, so objects weigh less on the Moon than they do here. That's why the astronauts could enjoy bouncing around on the lunar surface.