Buzz Aldrin shot down two MiG-15 aircraft. After earning a Sc.D. degree in astronautics from the Massachusetts Institute of Technology, Aldrin was selected as a member of NASA's Astronaut Group 3, making him the first astronaut with a doctoral degree. His doctoral thesis was "Line-of-Sight Guidance Techniques for Manned Orbital Rendezvous", earning him the nickname "Dr. Rendezvous" from fellow astronauts. His first space flight was Gemini 12 during which he spent over five hours on extravehicular activity (EVA) outside the spacecraft. Aldrin set foot on the Moon at 03:15:16 on July 21, 1969 (UTC), nine minutes after Armstrong first touched the surface,
Buzz Aldrin 18, 1963. This made him the first astronaut with a doctoral degree. Combined with his expertise in orbital mechanics, it earned him his nickname from his fellow astronauts. "From the outset," Walter Cunningham, a fellow member of the 1963 group, recalled, "Buzz was referred to as 'Dr. Rendezvous' because of his obsession with rendezvous in space." Aldrin was aware that it was not always intended as a compliment. Jim Lovell and Aldrin were selected as the backup commander and pilot respectively of Gemini 10. Backup crews usually became the prime crew of the third following mission, but in this case