The National Aeronautics and Space Administration is an independent agency of the U.S. federal government responsible for the civil space program, aeronautics research, and space research.

NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the US space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. Since its establishment, most American space exploration efforts have been led by NASA, including the Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA is supporting the International Space Station and overseeing the Orion spacecraft's development, the Space Launch System, Commercial Crew vehicles, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management for uncrewed NASA launches.

NASA's science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate's Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic spacecraft such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories and associated programs.

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