Sian Hayley "Leo" Proctor (March 28, 1970) is an American commercial astronaut, geology professor, artist, author, and science communicator. She became the first female commercial spaceship pilot and the first artist selected to go to be an astronaut on the all-civilian Inspiration4 orbital spaceflight, 15 September 2021. As pilot of the Inspiration4's SpaceX Crew Dragon space capsule, Proctor became the first African-American woman to pilot a spacecraft. She was also the education outreach officer for the first Hawaii Space Exploration Analog and Simulation (HI-SEAS) Mission. In 2024, Proctor was selected to be a U.S. Science Envoy for the United States Department of State.