John Glenn was not popular with the other astronauts. Glenn was the backup pilot for Shepard and Grissom on the first two manned Project Mercury flights, the sub-orbital missions Mercury-Redstone 3 and Mercury-Redstone 4. Glenn was selected for Mercury-Atlas 6, NASA's first manned orbital flight, with Carpenter as his backup. Putting a man in orbit would achieve one of Project Mercury's most important goals. Shepard and Grissom had named their spacecraft "Freedom 7" and "Liberty Bell 7". The numeral 7 had originally been the production number of Shepard's spacecraft, but had come to represent the Mercury 7. Glenn named his spacecraft, number
John Glenn and a minimum altitude of (perigee). The flight made Glenn the first American to orbit the Earth, the third American in space, and the fifth human in space. The mission, which Glenn called "best day of his life", renewed U.S. confidence. His flight occurred while the U.S. and the Soviet Union were embroiled in the Cold War and competing in the Space Race. As the first American in orbit, Glenn became a national hero, met President John F. Kennedy, and received a ticker-tape parade in New York reminiscent of those honoring Charles Lindbergh and other heroes. He became "so valuable