He blasted to American hero status on Feb. 20, 1962, when he became the first American to orbit the Earth. Then, in a spectacular return to space, he joined the crew aboard the shuttle Discovery in 1998, which made 134 orbits and racked up 3.6 million miles during its nine-day mission.
Glenn, 77 at the time, became the oldest human to experience space travel.
Glenn grew up in New Concord, Ohio, where his parents owned a plumbing business and ran a boarding house for college students.
His father gave him his first taste of aviation when he bought them both a ride in a WACO biplane, which was built in Troy.
» PHOTOS: How John Glenn progressed from American hero to public servant
At age 21, he enlisted in the Navy, transferred to the Marine Corps and worked his way into a fighter unit. His accomplishments included combat duty in two wars, two flights as an astronaut, four terms in the U.S. Senate and building a public affairs program at Ohio State University. But when asked what achievement he was most proud of — a question he got often — Glenn’s answer was his enduring marriage to Annie, his lifelong companion.
They met as toddlers in a playpen in New Concord, were married in their hometown on April 6, 1943, and appeared together well into their 90s, usually holding hands.
» RECENT HONOR: Columbus airport to be renamed after John Glenn
In April 1959, NASA selected him as one of the first seven astronauts in the Project Mercury space program. At 9:47 a.m. on Feb. 20, 1962 – five years after the Soviets had put a man into outer space – Glenn was strapped in atop an Atlas rocket with 367,000 pounds of thrust, blasting the Ohioan and the Friendship 7 capsule off the Cape Canaveral launch pad and into orbit 162 miles above the earth.
“Godspeed, John Glenn,” said fellow astronaut Scott Carpenter as Americans watched transfixed and worried.
When Carpenter died in 2013, Glenn became the last surviving member of the Mercury 7.
» How valuable was John Glenn's 1962 mission?
After his 1962 orbit, Glenn served in an advisory role to NASA before shifting to business and public affairs. Robert F. Kennedy was among those who encouraged him to run for U.S. Senate, where he was elected in 1974 and served until 1999.
John Glenn - Through the Years
Glenn was often mentioned as a possible running mate for Democratic presidential candidates, and he ran for president in 1984, just as just as “The Right Stuff” made him even more of a household name. But Glenn’s presidential campaign faltered and he carried a campaign debt from his efforts for years afterward.
In recent years, Glenn campaigned for Democratic presidential candidates Al Gore, John Kerry and Barack Obama as well as for Sherrod Brown for U.S. Senate and Ted Strickland for governor.
In November 2011, he and the crew of the first moon landing were awarded the Congressional Gold Medal. The medal, first awarded in 1776 to Gen. George Washington and John Paul Jones during the American Revolutionary War, goes to an individual who performs an outstanding act of service to the security, prosperity, and national interest of the United States.