The Mercury Seven. Front row, from left: Walter M. Schirra Jr., Donald K. “Deke” Slayton, John H. Glenn Jr. and M. Scott Carpenter. Back row: Alan B. Shepard Jr., Virgil I. “Gus” Grissom and L. Gordon Cooper Jr. (NASA)

“Some fine early morning before another summer has come, one man chosen from the calmly intent seven . . . will embark on the greatest adventure man has ever dared to take. Dressed in an all-covering suit to protect him from explosive changes in pressure, strapped into a form-fitting couch to cushion him against the crushing forces of acceleration, surrounded in his tiny chamber by all manner of instruments designed to bring him safely home, he will catapult upward at the head of a rocket for more than 100 miles and then plunge down into the Atlantic Ocean. If he survives, he will be come the heroic symbol of a historic triumph; he will be the first American, perhaps the first man, to be rocketed into the dark stillness of space. If he does not survive, one of his six remaining comrades will go next.”

This is how, in September 1959, Life Magazine introduced the Mercury Seven — NASA's first astronauts. At that point, no person had even attempted to reach space. Rockets routinely blew up on the launchpad. Most of the animals sent into space didn't come back alive. There was no guarantee that the project would work. Yet these men had volunteered to be strapped into a rocket and blasted off the only planet humanity has ever known.

John Glenn, who died Thursday at age 95, was the last surviving member of the “magnificent” Mercury Seven, the astronauts who proved that America really could make it to space. He, Alan Shepard, Scott Carpenter, Gordon Cooper, Gus Grissom, Wally Schirra and Deke Slayton, were devoted, fearless, diligent, bold — all those heroic attributes that Tom Wolfe waxes poetic about in “The Right Stuff.”

But what is truly astonishing about Glenn and his colleagues was their willingness to stake their lives on something that seemed impossible. This was more than just sailing into uncharted waters. It was tantamount to setting foot on the very first boats. It was incredibly courageous, and a little bit crazy.

And the Mercury Seven knew it.

Writing in Life in 1959, Carpenter recalled showing his California home to potential tenants just before he left for training at Houston's Johnson Space Center. A pleasant-looking middle-aged woman came up to him and asked, “Are you one of those spacemen, Mr. Carpenter?”

“Yes, I am.”

“Well, you're a nut,” the woman told him. Then she turned and walked away.

In his book “The Real Space Cowboys,” written with Ed Buckbee, Schirra said he “didn't really volunteer” for the Mercury Seven. He'd been ordered to Washington to attend a presentation about the program, and as he listened to engineers and psychologists describe the thrill of riding a rocket, “I was immediately looking for the door,” he wrote.

“And they said, ‘Not to worry, we'll send a chimpanzee first!’" As if that was much comfort.


Alan Shepard in his silver pressure suit, just before he became the first American to fly into space. (NASA)

The chimp, named Ham, survived his January 1961 flight onboard a Mercury Redstone rocket, emerging tired and slightly dehydrated, but otherwise none the worse for wear. So four months later, on May 5, Shepard clambered atop a very similar rocket, ready to become the first American in space.

The pressure to succeed was overwhelming, particularly because Soviet cosmonaut Yuri Gagarin had just completed an orbit of Earth the previous month.

“It was one of the most thrilling of the flights; perhaps, in a sense, the most fearful for me,” CBS anchor Walter Cronkite, who was at Cape Canaveral, Fla., for the launch, would recall at an anniversary event 30 years later. “We had watched Redstone rockets blowing up on the pad and blowing up in test flights. I had a strong feeling that perhaps we were rushing the launching of man into space to compete with the Russians. I really had my fingers crossed.”

[What happened when John Glenn orbited the Earth]

For four unbearable hours, Shepard sat inside the cramped Mercury capsule as engineers tested and adjusted and retested every aspect of the craft. If he was preoccupied by thoughts of every disaster that could befall him, he didn't discuss them. (A story about Shepard relieving himself in his spacesuit, on the other hand, is now NASA legend.)

In the end, it took just 15 minutes for Shepard to soar 115 miles above Earth, graze the edge of space, and plummet back into the sea.

''He crawled on top of that rocket that had never before flown into space with a person aboard and he did it. That was an unbelievable act of courage,” former NASA administrator Daniel Goldin told the New York Times after Shepard died in 1998.


John Glenn enters the Mercury Friendship 7 spacecraft before launch from Cape Canaveral. (NASA)

The next impossible task was to not just touch space, but navigate it. That job fell to John Glenn the following year. He would be orbiting the Earth on an Atlas rocket — known for its power but not for reliability. The very first time Glenn watched one of these rockets launch, it blew up. “That wasn't a confidence builder,” he said at a 50th anniversary event organized by NASA.

In an essay for Life, Glenn wrote that he dwelled endlessly on the prospect of flight. Several times a day, he tried to visualize the moment of lift off, what it would be like to feel the Earth recede beneath him, to sense gravity loosen its grip.

His launch was delayed several times, but Glenn projected confidence as he prepped to take flight on the morning of Feb. 20, 1962. “You fear the least what you know the most about,” he once said.

But NASA engineers, who watched his rocket take off via periscope from a bunker 1,000 feet away, marveled at the astronaut's courage.

The flight, which took four hours, 55 minutes and 23 seconds, was uneventful until its final moments.

In this clip from a 1962 NASA documentary, John Glenn launches into space aboard the Friendship 7 on the first orbital flight by an American astronaut. (NASA)

“As I got into the heat of reentry,” he told The Washington Post in 1987, “I glanced out the window, and there were big flaming chunks that were coming back by the window, back along the flight path, and . . . I can still see them to this day, they were so vivid. A lot of little sparks, pieces and so on, but good sized chunks [too]. And I couldn't be certain at that time whether it was the retro-pack or the heat shield. So that caused considerable apprehension.”

It was the heat shield, which had come loose from the force of reentry. A light flickered on at mission control warning that the shield could come off. Everyone in that engineer bunker knew that the spacecraft might burn up, and Glenn with it.

There was nothing but silence for a few, harrowing minutes as communications were cut by the ionization barrier that built up around the plummeting capsule. Then, a moment after splashdown, Glenn's voice came across the radio saying, “Boy, that was a real fireball!”

These days, Americans are sent into space several times a year, and rocket launches feel almost routine. Certainly, there's still a lot that can go wrong. But Glenn and his colleagues proved that it can also go right. We can be a space-faring species.

For evidence of that impossibility-made-real, just go outside and look up: High above us, humans are circling the Earth aboard the International Space Station, a tiny pinprick of light spinning across the sky.

Correction: A previous version of this article misstated the date of Glenn’s orbital flight. It was Feb. 20, 1962. 

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