John Herschel Glenn Jr. flew into the history books on Feb. 20, 1962, when he became the first American to go into orbit. But his trajectory to greatness was set years earlier, as a Marine Corps pilot. Glenn flew 59 combat missions in World War II and 90 combat missions in the Korean War. Here we see Glenn climbing out of the cockpit of his F-8-UI Crusader jet at Brooklyn's Floyd Bennett Field in 1957, after making the first nonstop, supersonic flight from Los Angeles to New York. The flight was called "Project Bullet" because Glenn traveled faster than a bullet. The 3-hour, 23-minute trip set a transcontinental speed record, and put Glenn on the radar screen for selection as an astronaut a couple of years later.
Glenn and six other military fliers were selected in 1959 to become the first American astronauts as part of Project Mercury. NASA put the "Mercury 7" through a grueling series of medical and psychological tests. Glenn is seen here being outfitted with a biosensor during astronaut training activities at Cape Canaveral, Fla., in 1961.
The seven Mercury astronauts pose for a photo in their spacesuits in 1962. Front row, left to right, are Wally Schirra, Deke Slayton, John Glenn and Scott Carpenter. Back row, from left, are Alan Shepard, Gus Grissom and Gordon Cooper. As of 2012, only Glenn and Carpenter are still alive.
By 1962, astronauts Alan Shepard and Gus Grissom had flown on suborbital Mercury missions. Those flights set the stage for John Glenn's orbital odyssey. Glenn took a no-nonsense, straight-arrow approach to his physical training program, including frequent runs like this one in 1962.
John Glenn's orbital flight was initially set for launch in January 1962, but postponements pushed it back to Feb. 20. Glenn's Friendship 7 capsule was launched atop an Atlas rocket from Cape Canaveral as an estimated 60 million people watched via live television. Fellow astronaut Scott Carpenter called out to him over a radio link from the launch pad's blockhouse: "Godspeed, John Glenn!"
During Friendship 7's three-orbit flight, NASA controllers saw indications that the capsule's heat shield had come loose - which could be a fatal flaw for re-entry. They told Glenn not to jettison the craft's retro-rocket pack, as an added precaution. Glenn ended up making a safe splashdown in the Atlantic Ocean, and it turned out that the apparent heat-shield problem was merely due to a sensor failure. Here you see Glenn's capsule attached to a retrieval cable hanging down from a helicopter. The capsule released green dye into the water to help searchers find it from the air.
President John F. Kennedy, astronaut John Glenn and Gen. Leighton I. Davis, commander of the Air Force Missile Test Center, ride together in the back seat during a 1962 parade in Cocoa Beach, Fla., to celebrate America's first human orbital spaceflight.
Astronaut John Glenn, far right, accompanies his family onto an Air Force plane in Key West, Fla., on Feb. 26, 1962, en route to a series of celebrations after his spaceflight. From left are his wife, Annie, their daughter Lyn and their son David. John and Annie were childhood playmates and high-school sweethearts while growing up in New Concord, Ohio. They were married in 1943, just after John Glenn received his commission in the Marine Corps.
Astronaut John Glenn, riding in the car seen at left, gets a huge New York welcome on March 1, 1962, during a ticker-tape parade along Broadway on the way to a City Hall ceremony.
Astronaut John Glenn and First Lady Jacqueline Kennedy water-ski on a tandem tow on Massachusetts' Lewis Bay, near Hyannis Port, on July 22, 1962. Glenn and his family were the weekend house guests of Jackie's brother-in-law, Attorney General Robert F. Kennedy.
NASA made it clear that John Glenn would not be going back into space anytime soon - he was just too important as a national hero. Glenn left the astronaut corps in 1964 and decided to get into politics. At a 1969 news conference in Columbus, Ohio, he announced his candidacy for the Democratic nomination for U.S. senator. He lost out to fellow Democrat Howard Metzenbaum in the 1970 primary, but in 1974, Glenn prevailed and finally entered the Senate.
Sen. John Glenn confers with a fellow Democrat on the Senate Foreign Relations Committee, Joe Biden, during a 1981 hearing on the sale of an AWACS radar plane to Saudi Arabia. Glenn would serve in the Senate until 1999, while Biden would go on to become vice president in 2009.
Thirty-six years after John Glenn's first orbital flight, NASA decided to give him another space shot on the shuttle Discovery in 1998, during his final months as a U.S. senator. Here you see Glenn checking the communications system on his headgear, prior to bailout training at Johnson Space Center in Texas on April 12, 1998. Jean Alexander, a NASA suit expert, waits to help him with his helmet.
President Bill Clinton gets a helping of a space shuttle meal from senator/astronaut John Glenn while shuttle commander Curt Brown looks on, during a tour of the space shuttle mockup at NASA's Johnson Space Center in Texas on April 14, 1998.
Senator-astronaut John Glenn works on the shuttle Discovery's Advanced Organic Separation experiment after the STS-95 mission's launch on Oct. 29, 1998. Glenn was accompanied on the nine-day research flight by four other U.S. astronauts, a Spaniard and a Japanese spaceflier. The trip made Glenn the oldest human to fly in space, at the age of 77.
Senator-astronaut John Glenn and his wife Annie, along with other members of the shuttle Discovery's crew, parade up Broadway's "Canyon of Heroes" on Nov. 16, 1998. This was the second time Glenn received a ticker-tape parade in New York. The first one came after his history-making 1962 orbital flight.
At the age of 90, retired senator-astronaut John Glenn shows off his Congressional Gold Medal in the Capitol Rotunda on Nov. 16, 2011, flanked on the left by Senate Majority Leader Harry Reid, D-Nev., and on the right by Senate Minority Leader Mitch McConnell, R-Ky. Glenn received the medal for helping to "pave the way for the first lunar landing" in 1969.
This Jan. 25 photo shows retired Sen. John Glenn at his office in Columbus, Ohio. It's been 50 years since his milestone spaceflight in a Mercury capsule, and almost 14 years since his space shuttle flight and retirement from the Senate. "I've been very fortunate to have a lot of great experiences in my life, and I'm thankful for them," he says.