By the light of a waning moon, the shuttle Atlantis fell back to Earth, dropping out of predawn darkness to complete NASA's 135th and final shuttle voyage, a long-awaited (and long-dreaded) milestone marking the end of an era for American manned space flight.
Supplies for the space station program are absolutely critical for it's operation.
So two companies, Space Exploration Technologies ( Also known as SpaceX) and Orbital Sciences, are to begin building
unmanned cargo ships to take over transporting supplies to the shuttle.
Initial test flights are expected to begin later this year or early 2012.
