What a life

Via Wikipedia:

When the Japanese attack on Pearl Harbor brought the United States into World War II, Glenn quit college to enlist in the U.S. Army Air Corps. However, he was never called to duty, and in March 1942 enlisted as a United States Navy aviation cadet. He went to the University of Iowa for preflight training, then continued on to NAS Olathe, Kansas, for primary training. He made his first solo flight in a military aircraft there. During his advanced training at the NAS Corpus Christi, he was offered the chance to transfer to the U.S. Marine Corps and took it.

Upon completing his training in 1943, Glenn was assigned to Marine Squadron VMJ-353, flying R4D transport planes. He transferred to VMF-155 as an F4U Corsair fighter pilot, and flew 59 combat missions in the South Pacific.  He saw combat over the Marshall Islands, where he attacked anti-aircraft batteries on Maloelap Atoll. In 1945, he was assigned to NAS Patuxent River, Maryland, and was promoted to captain shortly before the war's end.

Glenn flew patrol missions in North China with the VMF-218 Marine Fighter Squadron, until it was transferred to Guam. In 1948 he became a flight instructor at NAS Corpus Christi, Texas, followed by attending the Amphibious Warfare School.

Glenn's Sabre jet

During the Korean War, Glenn was assigned to VMF-311, flying the new F9F Panther jet interceptor. He flew his Panther in 63 combat missions, gaining the nickname "magnet ass" from his alleged ability to attract enemy flak. On two occasions, he returned to his base with over 250 holes in his aircraft.  For a time, he flew with Marine reservist Ted Williams, a future Hall of Fame baseball player for the Boston Red Sox, as his wingman. He also flew with future Major General Ralph H. Spanjer.

Glenn flew a second Korean combat tour in an interservice exchange program with the United States Air Force, 51st Fighter Wing. He logged 27 missions in the faster F-86F Sabre and shot down three MiG-15snear the Yalu River in the final days before the ceasefire.

For his service in 149 combat missions in two wars, he received numerous honors, including the Distinguished Flying Cross (six occasions) and the Air Medal with eighteen award stars.

Glenn returned to NAS Patuxent River, appointed to the U.S. Naval Test Pilot School, graduating in 1954.  He served as an armament officer, flying planes to high altitude and testing their cannons and machine guns.^[15] He was assigned to the Fighter Design Branch of the Navy Bureau of Aeronautics (now Bureau of Naval Weapons) as a test pilot on Navy and Marine Corps jet fighters in Washington, D.C., from November 1956 to April 1959, during which time he also attended the University of Maryland.

Glenn had nearly 9,000 hours of flying time, with approximately 3,000 hours in jet aircraft.

On July 16, 1957, Glenn completed the first supersonic transcontinental flight in a Vought F8U-3P Crusader.  The flight from NAS Los Alamitos, California, to Floyd Bennett Field, New York, took 3 hours, 23 minutes and 8.3 seconds.

 For this mission Glenn received his fifth Distinguished Flying Cross.

In 1958, the newly formed NASA began a recruiting program for astronauts. Requirements were that each had to be a military test pilot between the ages of 25 and 40 with sufficient flight hours, no more than 5'11" in height, and possess a degree in a scientific field. 508 pilots were subjected to rigorous mental and physical tests, and finally the selection was narrowed down to seven astronauts (Glenn, Alan Shepard, Gus Grissom, Scott Carpenter, Wally Schirra, Gordon Cooper, and Deke Slayton), who were introduced to the public at a NASA press conference in April 1959. Glenn just barely met the requirements as he was close to the age cutoff of 40 and also lacked the required science-based degree at the time. During this time, he remained an officer in the United States Marine Corps.

John Glenn in his Mercury spacesuit

Glenn became the first American to orbit the Earth, aboard Friendship 7 on February 20, 1962, on the Mercury-Atlas 6 mission, circling the globe three times during a flight lasting 4 hours, 55 minutes, and 23 seconds. This made Glenn the third American in space and the fifth human being in space.

Zero G, and I feel fine.

— Glenn's first words on becoming weightless upon reaching orbit, February 20, 1962.

All original seven Mercury astronauts have now passed away, ending an era.