Recipients of the NASA Exceptional Service Medal

Joe Henry Engle (born August 26, 1932) is an American pilot, aeronautical engineer and former NASA astronaut. He was the commander of two Space Shuttle missions including STS-2 in 1981, the program's second orbital flight. He also flew two flights in the Shuttle program's 1977 Approach and Landing Tests. Engle is one of twelve pilots who flew the North American X-15, an experimental spaceplane jointly operated by the Air Force and NASA, and the last surviving test pilot of the aircraft. After Richard H. Truly died In 2024, Engle is now the last surviving crew member of STS-2.
As an X-15 pilot, Engle made three flights above 50 miles, thus qualifying for astronaut wings under the American convention for the boundary of space. In 1966 he was selected for NASA's 5th Astronaut Group, joining the Apollo program. He was backup Lunar Module Pilot (LMP) for Apollo 14 and originally scheduled as LMP for Apollo 17. However, cancellation of later flights prompted NASA to select geologist-astronaut Harrison Schmitt as LMP, displacing Engle.

Walter Marty Schirra Jr. (, March 12, 1923 – May 3, 2007) was an American naval aviator, test pilot, and NASA astronaut. In 1959, he became one of the original seven astronauts chosen for Project Mercury, which was the United States' first effort to put humans into space. On October 3, 1962, he flew the six-orbit, nine-hour, Mercury-Atlas 8 mission, in a spacecraft he nicknamed Sigma 7, becoming the fifth American and ninth human to travel into space. In December 1965, as part of the two-man Gemini program, he achieved the first space rendezvous, station-keeping his Gemini 6A spacecraft within 1 foot (30 cm) of the sister Gemini 7 spacecraft. In October 1968, he commanded Apollo 7, an 11-day low Earth orbit shakedown test of the three-man Apollo Command/Service Module and the first crewed launch for the Apollo program.
Before becoming an astronaut, Schirra graduated with a Bachelor of Science degree from the United States Naval Academy in 1945, and served at sea during World War II. In 1948, he became a naval aviator, served as a fighter pilot and flew 90 combat missions in the Korean War, and then in 1958 he graduated from the U.S. Naval Test Pilot School. Schirra retired from the Navy in 1969 with the rank of captain.
Schirra was the first astronaut to go into space three times, and the only astronaut to have flown into space in the Mercury, Gemini, and Apollo programs. In total, he logged 295 hours and 15 minutes in space. After Apollo 7, he retired as a captain from the U.S. Navy as well as from NASA, subsequently becoming a consultant to CBS News in the network's coverage of following Apollo flights. Schirra joined Walter Cronkite as co-anchor for all seven of NASA's Moon landing missions.