John Glenn and Friendship 7 (1962): First American to Orbit

John Glenn became the first American to orbit the Earth on 20 February 1962, circling the planet three times in the Mercury capsule Friendship 7. The flight from Cape Canaveral, Florida, lasted just under five hours and included a tense re-entry after a false warning about the capsule’s heat shield. Coming ten months after Yuri Gagarin’s orbital flight, it showed that the United States had caught up in human spaceflight and turned Glenn into a national hero.

Background: catching up in orbit

By early 1962 the Soviet Union was well ahead in the Space Race. Yuri Gagarin had made a single orbit on 12 April 1961, and in August that year Gherman Titov had spent a full day in orbit aboard Vostok 2. The United States had flown only two short suborbital missions, by Alan Shepard in May 1961 and Gus Grissom in July.

To reach orbit, NASA’s Project Mercury needed the Atlas, a much more powerful rocket originally built as an intercontinental ballistic missile. The Atlas had a troubled test record, including an explosion during a Mercury test flight in 1960. After further tests, a Mercury-Atlas flight in November 1961 carried the chimpanzee Enos on two orbits and returned him safely, clearing the way for a crewed flight.

John Glenn, a 40-year-old Marine Corps pilot, was chosen for the first orbital mission. He was a decorated veteran of the Second World War and the Korean War and had set a transcontinental speed record in 1957. Scott Carpenter served as his backup.

Delays and the launch

The flight, officially Mercury-Atlas 6, was postponed many times between December 1961 and February 1962 because of technical problems and poor weather. On 27 January 1962 Glenn spent more than five hours in the capsule before the launch was cancelled because of clouds. The repeated delays drew huge public attention.

On the morning of 20 February 1962 Glenn finally lifted off from Launch Complex 14 at 9:47 a.m. Eastern time. As the rocket rose, Carpenter radioed the famous words “Godspeed, John Glenn”. Millions of Americans watched on television or listened on radio, and schools across the country stopped lessons to follow the launch.

Three orbits

The Atlas placed Friendship 7 in an orbit ranging roughly from 160 to 260 kilometres above the Earth, travelling at about 28,200 kilometres per hour (17,500 miles per hour). Each orbit took about 88 minutes. Glenn was busy with tests and observations: he photographed the Earth, monitored his health and reported on how a human could function in weightlessness. He ate food from tubes, showing that swallowing worked normally without gravity.

At his first sunrise in orbit, over the Pacific, Glenn saw thousands of tiny glowing particles drifting around the capsule. He described them as “fireflies”. Their origin was a mystery during the flight; on the next Mercury mission Scott Carpenter showed that they were flakes of frost shaken from the outside of the spacecraft and lit by the sun.

Near the end of the first orbit a small thruster in the automatic control system began to malfunction, making the capsule drift. Glenn took over and flew Friendship 7 manually for much of the rest of the flight. This proved the value of having an astronaut able to control the spacecraft, something Mercury engineers had debated.

People on the ground also took part. As Friendship 7 passed over Perth, Western Australia, at night, residents switched on their lights, and Glenn reported seeing the city glow below him.

The heat-shield scare

During the second orbit, flight controllers in Mercury Control saw a worrying signal, known as “Segment 51”. It indicated that the landing bag, a cushion between the heat shield and the capsule, had deployed, which would mean the heat shield was no longer locked in place. If the shield came loose during re-entry, Glenn would be burned up.

After discussion, controllers including the flight director Christopher Kraft decided that Glenn should keep the retro-rocket pack, normally jettisoned after firing, strapped over the heat shield during re-entry. The straps might help hold the shield in place. Glenn was told only part of the reasoning at first.

As he re-entered the atmosphere, Glenn saw large flaming pieces of the retro-pack flying past his window, and he could not be sure whether the heat shield was breaking up. The capsule went through the expected radio blackout. When contact returned, he was safe. Engineers later found that the signal had come from a faulty sensor switch and that the shield had never been loose.

Splashdown and return

Friendship 7 splashed down in the Atlantic Ocean at 2:43 p.m. Eastern time, after a flight of 4 hours, 55 minutes and 23 seconds. It landed about 64 kilometres (40 miles) from its planned point, because the capsule’s computed weight had not allowed for the fuel already consumed. The destroyer USS Noa picked up the capsule, with Glenn inside, about 21 minutes later.

Glenn received an enormous welcome. On 23 February President John F. Kennedy presented him with the NASA Distinguished Service Medal at Cape Canaveral. On 26 February he addressed a joint session of Congress, and on 1 March New York held a ticker-tape parade for him and the other Mercury astronauts, attended by an estimated four million people.

Key people

• John Glenn (1921–2016), Marine Corps pilot and the first American to orbit the Earth.
• Scott Carpenter (1925–2013), Glenn’s backup and capsule communicator, who flew the next orbital mission, Aurora 7, in May 1962.
• Christopher Kraft (1924–2019), NASA’s first flight director, who managed the response to the heat-shield warning.
• Robert Gilruth (1913–2000), head of the Space Task Group running Project Mercury.

Consequences and legacy

Glenn’s flight restored American confidence and built public support for the Apollo programme, which aimed to land astronauts on the Moon by the end of the decade. Three more Mercury flights followed, ending with Gordon Cooper’s 22-orbit mission in May 1963.

Kennedy and NASA were reluctant to risk Glenn on another flight, and he resigned from NASA in 1964. He later went into politics and served as a Democratic senator for Ohio from 1974 to 1999. In 1998, at 77, he returned to space aboard the Space Shuttle Discovery, becoming at that time the oldest person to fly in space. The mission included studies of how spaceflight affects the ageing human body. Friendship 7 is displayed at the Smithsonian National Air and Space Museum in Washington, D.C.

Timeline

• 1961, 12 April: Yuri Gagarin makes the first orbital human flight.
• 1961, 29 November: The chimpanzee Enos completes two orbits on Mercury-Atlas 5.
• 1962, 27 January: Glenn’s launch is cancelled after he spends hours in the capsule.
• 1962, 20 February, 9:47 a.m.: Friendship 7 lifts off from Cape Canaveral.
• 1962, 20 February, 2:43 p.m.: Glenn splashes down after three orbits.
• 1962, 26 February: Glenn addresses a joint session of Congress.
• 1962, 1 March: New York holds a ticker-tape parade for Glenn.
• 1998, 29 October: Glenn returns to space aboard Discovery on STS-95.

Why it matters

Friendship 7 put the United States into orbit and showed that an astronaut could take control when automatic systems failed. Glenn’s calm under pressure during the heat-shield scare became part of the lasting image of the early astronauts, and his flight gave Americans renewed belief that they could compete, and eventually lead, in the race to the Moon.