On Monday, it will be exactly 50 years since the day John Glenn helped America turn the corner in the Space Race with the Soviets.

When Glenn became the first American to orbit the planet, it triggered a celebration and sense of pride that arguably was crucial to astronauts later setting foot on the moon.

So huge was this national mood swing that followers of CNN's Light Years space and science blog still remember it a half-century later. They're sharing their memories about where they were and what they felt on February 20, 1962.

"I was a junior in high school when John Glenn went on his ride around the Earth," wrote OldGoat in Light Years comments. "It seemed amazing at the time that such a thing could be done."

Glenn's 4 hour, 55 minute mission was really a giant tech-game of Cold War "catch-up." See more rare LIFE photos of Glenn during the Space Race.

It's easy to forget that not long before Glenn's three-orbit flight, the public knew NASA more "for its failures and delays than for its space exploration," wrote Tom Streissguth in his Glenn biography. "The Soviet space program was far more successful."

More than ten months before Glenn's flight, Moscow fired the first shot in this battle to dominate human space exploration, when cosmonaut Yuri Gagarin became the first man to orbit the Earth.

After Washington recovered from the shock, it answered with Alan Shepard and Gus Grissom - America's first and second men in space. But their 15-minute missions blasted off and then splashed down. No orbiting. They paled in comparison to Gagarin's single-orbit around-the-world ride.

Then Moscow embarrassed Washington again when Gherman Titov circled the planet - not once - but 16 times.

It sure looked like America might be on its way to losing the Space Race.

"Everything about the space program was cool back then and really gave the U.S. something to shoot for," said Light Years follower Bob Knippel. "It's not at all like that today, the way it permeated American consciousness."

Leading up to Glenn's mission, there were safety questions about his 125-ton Atlas rocket. Streissguth wrote that during one testing period the rocket "failed four out of every 10 launches."

"People have always asked if I was afraid," Glenn wrote in his 2000 memoir. "I wasn't. Constructive apprehension is more like it."

After many delays, the launch went without a hitch. But during re-entry a false alarm prompted worries about the spacecraft's protective heat shield. Light Years follower Montello recalled CBS news anchor "Walter Cronkite's nonstop commentary during the time Glenn was in space and the elation when he landed safely."

As Light Years commenter The_Mick, put it: "John Glenn's flight put us in the major leagues!" While Judie wrote, "I remember it well and was so proud; I still am!"

Watch rare archival film of Glenn's flight

In fact, the national celebration for Glenn's mission was so intense Washington held a parade for the 40-year-old Marine Corps colonel.

Thousands cheered as he left a White House meeting with President Kennedy and was driven down Pennsylvania Avenue to Capitol Hill. There, Glenn addressed Congress saying, "I believe we're on the brink of an era of expansion of knowledge about ourselves and our surroundings that is beyond comprehension." You can see Glenn's handwritten speech notes here.

The emotional momentum spurred by Glenn's successful flight culminated just seven years later, when Apollo 11's Neil Armstrong, Buzz Aldrin, Michael Collins and their colleagues accomplished a lunar landing that many said was impossible.

Now, a half-century after Glenn's flight, Light Years follower Gregory L. Faith told us he still has "a picture of Mr. Glenn in his U.S. Marine Corps uniform with his signature. It is my only prized possession of an era gone by."

Works4me summed up feelings for Glenn in three words.

"My first hero."

Our friends at Time and LIFE offer a glimpse of rare and unpublished images of Glenn by some of LIFE's finest photographers.

These images - some in the gallery above and others at LIFE's website - document a brief period, and some would say perhaps a more naive, less-cynical time, when Glenn and his astronaut colleagues inspired the nation.

What about now?

Who's inspiring the next generation?

And if not space, in what new competitive arenas will they test themselves? Stay tuned.

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