On May 5, 1961, a Redstone rocket hurled Alan Shepard’s Mercury capsule, Freedom 7, 116 miles (187 km) high and 302 miles (486 km) downrange from Cape Canaveral, Florida. Freedom 7 parachuted into the Atlantic just 15 minutes and 22 seconds later, after attaining a maximum velocity of 5,180 mph (8,336 km/h). Shepard, a Navy test pilot and NASA astronaut, became the first American to fly in space.

Shepard’s flight was a triumph, not least because it had been conducted live on national television and in front of the world press. It was a notable contrast to the secretive ways of the Communist-led Soviet Union. But 25 days earlier on April 12, 1961, Soviet Air Force pilot Yuri Gagarin had made a single orbit of the Earth, becoming the first human to travel beyond the atmosphere. It was just the latest Soviet space first, going back to Sputnik, the first artificial Earth satellite, in October 1957. Gagarin’s flight was yet another stunning propaganda success in the Cold War Space Race.

Earlier in 1961, however, it was not at all clear that the Soviets would come first. The Eisenhower Administration and Congress had created the National Aeronautics and Space Administration (NASA) in 1958, a year after Sputnik, in part to overtake the Soviet Union in space. The new agency’s Project Mercury hoped to launch an astronaut by 1960, which seemed possible because Mercury would have two launch vehicles. The smaller Army Redstone missile could send astronauts on short, suborbital journeys; the larger Air Force Atlas intercontinental ballistic missile (ICBM) would launch them into orbit—the project’s prime objective. The reliable Redstone was available many months earlier than the troubled Atlas, which was blowing up regularly. NASA officials also saw suborbital flights as valuable spaceflight experience; at one point they thought all seven astronauts picked in April 1959 would fly such missions. But technical delays piled up. The first uncrewed Mercury-Redstone flight only got off in December 1960. Mercury-Redstone 2 on January 31, 1961, carrying the chimpanzee Ham, was mostly successful, but the booster did not cut off in time, triggering the capsule’s escape system and sending it higher and farther than intended. NASA’s Marshall Space Flight Center in Huntsville, Alabama, which had grown out of the Army and was still situated at Redstone Arsenal, wanted an additional test. That meant another delay for the crewed Mercury-Redstone 3 (MR-3) launch, which could have happened in March of 1961 were it not for the extra test.

That delay brought tensions inside NASA to a boiling point. Mercury was run by the Space Task Group, an organization led by Robert Gilruth and situated at the Langley Research Center in tidewater Virginia. Gilruth’s group would soon become the Manned Spacecraft Center in Houston, Texas. Marshall was led by the famous German-American rocket engineer Wernher von Braun. Gilruth already disliked von Braun for being German and changing sides and his subordinates and the astronauts saw von Braun’s demand for a new test as timidity and German overengineering. NASA Headquarters in Washington, DC, ultimately decided in favor of Marshall because losing an astronaut was worse than losing the race. MR-BD (for Booster Development) flew successfully on March 24, 1961. That same month, the Soviets flew two successful orbital tests of their spacecraft. When Gagarin launched, they named it Vostok (East).

NASA had announced that three astronauts were candidates for MR-3: John Glenn, Virgil “Gus” Grissom, and Alan Shepard. A lot of things about that crew selection were never repeated, and for good reason. Highlighting those three implicitly diminished the other four: Scott Carpenter, Gordon Cooper, Walter Schirra, and Donald “Deke” Slayton. Moreover, Shepard was Gilruth’s choice from the outset, yet NASA concealed this until after the cancellation of the first launch attempt on May 2, 1961, due to bad weather. The press also learned that Shepard had named his capsule Freedom and added a 7 for the seven astronauts—a gesture of solidarity to the others. (Freedom 7 was also the seventh spacecraft built by the contractor, McDonnell Aircraft Corporation of St. Louis, Missouri.)

In the early morning darkness of May 5, 1961, Shepard climbed into his capsule atop the Redstone. Born in 1923 in Derry, New Hampshire, he had graduated from the Naval Academy in 1944, served on a destroyer in the last year of the war, took flight training, flew off carriers, and tested Navy jets. He entered Freedom 7 about two hours before scheduled launch at 7:20 am. Yet, technical delays dragged on—two stories about that wait were later made famous by Tom Wolfe’s book The Right Stuff. Shepard had to urinate in his spacesuit because no provision had been made for the astronaut to relieve himself, and when he became irritated with the delays, he allegedly told launch controllers: “Why don’t you fix your little problem and light this candle?” Shortly after that, at 9:34 am, they finally did.

The rocket burned for a little over two minutes with the acceleration ramming him into his couch with a force of over six “Gs” (six times Earth’s gravity). After separating, the capsule turned around and pointed the heatshield forward for reentry. During the five minutes of weightlessness, Shepard tested Freedom 7’s attitude control systems and extended the periscope to see back to Florida. (His capsule did not have the overhead window built into later vehicles.) Once over the top, it was time to fire the retrorockets—not needed for his flight, but a test of how to get out of orbit. The brief reentry was brutal, with peak “G” loads of over 11. Parachute deployment was normal, and his spacecraft hit the ocean with a jarring impact he compared to landing on an aircraft carrier. A Marine helicopter picked him up and took him to the USS Lake Champlain.

Now a national hero, Alan Shepard was decorated by President John F. Kennedy at the White House on May 8. Less than three weeks later, on May 25, 1961, Kennedy asked Congress to approve a program to land humans on the Moon, a direct response to Gagarin’s flight. If Shepard’s mission had failed, the president likely could not have made that announcement.

There were ironies in the aftermath of Shepard’s flight. Grissom flew a near-repeat on July 21, 1961, and then NASA cancelled further suborbital missions to concentrate on getting into orbit. When John Glenn circled the Earth three times in Friendship 7 on February 20, 1962, it eclipsed Shepard and Grissom in the public mind. Glenn was not only more charismatic; his mission finally equaled what the Soviets had done twice (Gherman Titov spent a day in space in August 1961). In 1963, Shepard was knocked off flight status for six years because of an inner-ear condition, but then, in the final irony, he became the only Mercury astronaut to go the Moon, commanding the Apollo 14 landing. He died in 1998, a legend. He will always be the first American, and second human, to fly in space, and the fifth to walk on the Moon.

Michael J. Neufeld is a senior curator in the Museum’s Space History Department and is responsible for Mercury and Gemini spacecraft, among other collections.