An unmanned SpaceX Dragon cargo ship is seen grappled by a robotic arm on the International Space Station on Sept. 22, 2014. The commercial spacecraft is SpaceX's fourth delivery mission to the space station and is carrying 20 live mice and the world's first 3D printer in space among its haul.
An unmanned SpaceX Dragon cargo ship delivers fresh NASA supplies to the International Space Station on April 17, 2015 in this still from a exterior station camera. It was SpaceX's sixth commercial cargo delivery for NASA.
SpaceX Launches NASA Cargo and Research To International Space Station