William Shepherd is an American astronaut and former United States Navy officer. He was born on July 26, 1949, in Oak Ridge, Tennessee. Shepherd became the first commander of the International Space Station (ISS) in 2000, leading the initial crew during its assembly in orbit. He has participated in multiple space missions, contributing to scientific research and international cooperation in space exploration. In addition to his work with the NASA, Shepherd has a background in engineering and has served in various roles within the military. He graduated from the United States Naval Academy and earned a master's degree in aerospace engineering. His career has significantly impacted human spaceflight and exploration.