Donald Kent "Deke" Slayton was an American Air Force pilot, aeronautical engineer, and test pilot who was selected as one of the original NASA Mercury Seven astronauts. He went on to become NASA's first Chief of the Astronaut Office and Director of Flight Crew Operations, responsible for NASA crew assignments.

The Chief of the Astronaut Office is the most senior leadership position for active astronauts at the National Aeronautics and Space Administration (NASA). The Chief Astronaut serves as head of the NASA Astronaut Corps and is the principal advisor to the NASA Administrator on astronaut training and operations. The Chief's responsibilities include managing Astronaut Office resources and operations and helping to develop operating concepts and assignments for astronaut flight crew.