- Chief astronaut of the Apollo-11 mission (landing a man on the Moon and returning him safely to Earth)
- First person to set foot on the Moon
- Commander of the Apollo-11 mission and chief astronaut of NASA's astronaut office in Houston
- Assistant chief of the astronaut office for operations and training
- Member of the Apollo-11 backup crew
- Member of the backup crew for the Gemini-X mission, later known as Gemini-X
- Member of the primary crew of the Gemini-VIII mission, which accomplished the world's first docking in orbit
- Member of the primary crew of the Gemini-V mission, which was canceled because of the deaths of the Apollo-1 crew