The Space Shuttle orbiter is the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter is a reusable winged space-plane, a mixture of rockets, spacecraft, and aircraft. This space-plane can carry crews and payloads into Earth orbit, perform on-orbit operations, then re-enter the atmosphere and land as a glider, returning her crew and any on-board payload to the Earth.