Collins first flew on Gemini 10 with John Young. The mission involved rendezvous — open definition and docking with an Agena target vehicle and gave Collins experience with EVA — open definition work outside the spacecraft. He later trained for Apollo and was assigned as Command Module Pilot for Apollo 11, the first lunar landing mission.

While Neil Armstrong and Buzz Aldrin descended to the surface in Eagle, Collins flew Columbia alone around the Moon. His role required precision, patience, and complete readiness to bring the crew home after lunar liftoff and rendezvous. Although he did not walk on the Moon, he was essential to the mission's success and became one of the most recognized command module pilots in history. After NASA, Collins served in public affairs and became the first director of the National Air and Space Museum.

Collins's background fit the broader pattern of the early astronaut corps: technical training, operational discipline, and a career built around difficult work before spaceflight. His formal education included United States Military Academy (B.S. Military Science, 1952). His service background is recorded as Major General, United States Air Force Reserve. His personal record also sits alongside a family life recorded as widowed, three children, a reminder that these careers unfolded within ordinary lives as well as national history.