NASAThe National Aeronautics and Space Administration (NASA ˈnæsə) is an independent agency of the U.S. federal government responsible for the civil space program, aeronautics research, and space research. Established in 1958, NASA succeeded the National Advisory Committee for Aeronautics (NACA) to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science.
Space Shuttle orbiterThe Space Shuttle orbiter is the spaceplane component of the Space Shuttle, a partially reusable orbital spacecraft system that was part of the discontinued Space Shuttle program. Operated from 1977 to 2011 by NASA, the U.S. space agency, this vehicle could carry astronauts and payloads into low Earth orbit, perform in-space operations, then re-enter the atmosphere and land as a glider, returning its crew and any on-board payload to the Earth. Six orbiters were built for flight: Enterprise, Columbia, Challenger, Discovery, Atlantis, and Endeavour.
Single-stage-to-orbitA single-stage-to-orbit (SSTO) vehicle reaches orbit from the surface of a body using only propellants and fluids and without expending tanks, engines, or other major hardware. The term usually, but not exclusively, refers to reusable vehicles. To date, no Earth-launched SSTO launch vehicles have ever been flown; orbital launches from Earth have been performed by either fully or partially expendable multi-stage rockets. The main projected advantage of the SSTO concept is elimination of the hardware replacement inherent in expendable launch systems.
Reusable launch vehicleA reusable launch vehicle has parts that can be recovered and reflown, while carrying payloads from the surface to outer space. Rocket stages are the most common launch vehicle parts aimed for reuse. Smaller parts such as rocket engines and boosters can also be reused, though reusable spacecraft may be launched on top of an expendable launch vehicle. Reusable launch vehicles do not need to make these parts for each launch, therefore reducing its launch cost significantly.
SpaceplaneA spaceplane is a vehicle that can fly and glide like an aircraft in Earth's atmosphere and maneuver like a spacecraft in outer space. To do so, spaceplanes must incorporate features of both aircraft and spacecraft. Orbital spaceplanes tend to be more similar to conventional spacecraft, while sub-orbital spaceplanes tend to be more similar to fixed-wing aircraft. All spaceplanes to date have been rocket-powered but then landed as unpowered gliders. Four types of spaceplanes have successfully launched to orbit, reentered Earth's atmosphere, and landed: the U.
