But it was all for naught. On Jan. 19, 1961, the director of NASA's Manned Spacecraft Center Robert Gilruth called the seven Mercury astronauts into his office. He asked each man to write on a slip of paper the name of the man other than himself he'd like to see make the first flight. After all his good behavior and diligent hard work, the first flight was coming down to a peer vote. A popularity contest was the one kind Glenn couldn't win in that group.
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Gilruth collected the astronauts' votes, and without saying how much their votes matter he announced that Alan Shepard would be first to fly. Gus Grissom would fly second. Glenn would be third. For privacy's sake, NASA told the media that all three astronauts were in the running for the first flight. The plan was to keep the secret until the morning Shepard walked out to the launch pad.
Glenn was furious, and he wouldn't let it lie. The next day he wrote a letter to Gilruth urging him to reconsider the flight lineup. His performance in training and classroom sessions ought to weigh heavier than his popularity, he argued. Glenn went so far as to appealed directly to NASA administrator Jim Webb, urging him to overrule Gilruth's decision. Webb outright rejected Glenn's plea. The letter to Gilruth went unacknowledged. Glenn watched as Shepard became the first American in space in space on May 5, 1961. He watched as Grissom followed suit on July 21. Then Glenn's luck changed.
The first two Mercury flights were short suborbital hops, and the plan had been for all seven astronauts to make the same mission before the first orbital flight. But with pressure mounting to keep pace with the Soviets and match Yuri Gagarin's orbital flight, NASA decided on Aug. 18 that it had gathered all the experience it could from suborbital missions. The next flight would go into orbit.
Suddenly, Glenn, the third American in line for a ride into space, had the first orbital mission dropped right in his lap.
Editor's note: On Dec. 8, 2016, John Glenn died at the age of 95 in his home state of Ohio. This article was originally published in 2013.
Image: John Glenn boards his Freindship 7 capsule before launch. Credit: NASA