Our Natural Satellite: The Moon
Object the Size of Mars
The moon is the only cellestial body where human beings have imprinted their footprints. It was on July 20, 1969, when Neil Armstrong step on the surface of the moon for the first time in the history of space race. The moon is characterized by two distinct landscapes: the cratered highlands and maria which is the latin word for sea. The two landscapes are covered by a thin layer of regolith.
It is beleived that the moon might have originated from the impact of a pristine solar system object the size of Mars which impacted with the earth 4.5 billion years ago. The tremendous impact of these two objects liberated the fragments which gave form to what we know as the moon.
Surface of the Moon
Because the moon lacks an atmosphere, it has been continuosly bombarded by asteroids and meteoroids which have covered the surface of the moon with their fragments. Almost the entire surface of the moon is covered by a mantle of powder known as regolith. Beneath the regolith mantle lies another mantle of fractured bedrock referred to as the megaregolith.
For a long time, explorations of the moon were set aside, and it was not until the 1990s that lunar explorations resumed with two robotic missions: Lunar prospector and Clementine. Both misions gave proofs of the presence of ice in the lunar poles; however, a controlled impact of robot Prospector into a crater near the south pole produced negative results of the presence of water ice.
First Images of the Apollo Mission Landing Site
Exploring the Moon
New international missions to the moon began in the beginning of this century with the SMART-1 from the European Space Agency in 2003. Kaguya spacecraft from Japan launched on September 14, 2007. Chang´e 1 from Chine launched on March 8, 2007, and Chandrayaan-1 launched on October 22, 2008. NASA resume a series of lunar explorations with Lunar Reconnaissance Orbiter and LCROSS which were launched in 2009. On July 17 2009, Lunar Reconnaissance Orbiter high technology instruments sent over 192 images and maps of the surface of the moon, including the apollo mission landing site. LCROSS mission is spected to excavate the dark floor of a crater in search of water, hydrocarbons, and hydrated particles.