Thomas Otten Paine was an American engineer, scientist and advocate of space exploration, and was the third Administrator of NASA, serving from March 21, 1969, to September 15, 1970.

The administrator of the National Aeronautics and Space Administration is the highest-ranking official of NASA, the national space agency of the United States. The administrator is NASA's chief decision maker, responsible for providing clarity to the agency's vision and serving as a source of internal leadership within NASA. The office holder also has an important place within United States space policy, and is assisted by a deputy administrator.