Asked in Apollo Moon Missions
The Apollo photos taken on the moon show weathered mountains in the background. How did the terrain on the moon become weathered with no wind or rain?
The moon is under a constant bombardment by micrometeorites (tiny meteorites the size of sand grains). This "sandblasting" effect can wear mountains down over long periods of time. Some have argued that these mircometeorites would kill an astronaut. This is not true for a number of reasons. First, mircometeorites are typically about the size of a grain of sand, which means that although the may be travelling very fast, their small mass means they don't have a terribly high amount of momentum, and thus can easily be stopped with a spacesuit. Second, the spacesuits the astronauts wore on the Apollo missions had a multi-layer design designed to stop micrometeorites (as well as absorb radiation) before they penetrated the innermost layer, which of course was the layer that separated the astronaut from the unforgiving vaccum of space. If anybody wishes to discuss this, please use the discussion page.