United States. National Aeronautics and Space Administration

Collins, who died April 27, orbited in Apollo 11 while Neil Armstrong and Buzz Aldrin made their historic moon walk. Speaking to Fresh Air in 1988, he described his solo orbit as "completely serene."

The legendary aviator, who died Dec. 7, served as a fighter pilot in World War II. Later, as a test pilot, he was the first person to fly faster than the speed of sound. Originally broadcast in 1988.