Throughout humanity's space saga, there have been many historic firsts, from being launched into space to setting foot on the moon.
Marine Lt. Col. John Glenn, in a space flight suit, reaches for some of the controls inside a Mercury capsule procedures trainer as he shows how the first U.S. astronaut will ride through space during a demonstration at the National Aeronautics and Space Administration Research Center in Langley Field, Virginia, the U.S, Jan. 11, 1961.
Russian Poet, Yevgeny Yevtushenko, (L) listens as Kennedy Space Center Director Dr. Kurt H. Debus explains the space shuttle program during the poet's visit to Cape Kennedy, Florida, U.S., April 15, 1972.
Many of the key rocket scientists behind both the American and Soviet space programs were Germans, who had worked on Adolf Hitler's "secret weapons," the V-1 and V-2 rockets. Some 1,600 German rocket experts were secretly taken to the U.S. in the dying days of World War II, while the Russians rounded up about 2,000 in one night at gunpoint and sent them to work in the Soviet Union.
Dr. Wernher von Braun, director of NASA's manned flight center, speaks to thousands of cheering Huntsvillians after the successful conclusion of the Apollo 11 lunar flight, July 25, 1969. Manned Flight Center is located in Huntsville, Alabama, U.S.
The inventor of Hitler's V-2 rocket – the world's first guided ballistic missile – was the architect of the U.S. Apollo program that would put a man on the Moon. Brought across the Atlantic with his brother Magnus, he came up with the Saturn V rocket that powered the American lunar missions. He died in 1977 still advocating manned missions to Mars.
Kennedy Space Center Director Dr. Kurt H. Debus folds his hands during an interview where he explains the future space programs after the launch of Apollo 17 in New York, the U.S., Nov. 17, 1972.
A friend of Von Braun, Debus was Hitler's flight test director for the V-1s and V-2s. In 1952, he began the building of rocket launch facilities at Cape Canaveral in Florida and was later director of operations of what would become the Kennedy Space Centre, overseeing the flight by the first U.S. astronaut Alan Shepard and the Moon missions.
The first man in space Yuri Gagarin and his wife Valentina is on a display at the upper house of the Russian parliament in Moscow, Russia, April 5, 2011.
The first man in space, Gagarin was chosen from 3,000 candidates. He completed a single 108-minute orbit aboard Vostok-1 on April 12, 1961 after declaring "Let's Go!" He died in 1968 at the age of 34 in a still-unexplained plane crash.
The undated photo shows Russian cosmonaut Major Gherman Titov who made the first space flight of more than 24 hours aboard Vostok 2, Aug. 6, 1961.
Gagarin's understudy for the historic 1961 flight, Titov, never got over the disappointment. Four months later, he orbited the Earth 17 times on Vostok-2. He was elected to the Russian parliament in 1995.
Cosmonaut Alexei Leonov, who stepped into space from the Voskod-2 spaceship, speaks in Moscow, Russia, March 26, 1965.
The then 30-year-old made the first spacewalk in history from Voskhod 2 in 1965. It lasted 12 minutes and nine seconds and nearly killed him as his spacesuit inflated due to the lack of atmospheric pressure. He had to bleed off some of the oxygen, risking death. Leonov later took part in the groundbreaking Apollo-Soyuz mission that opened a new era of space cooperation between the Soviets and the U.S. in 1975.
Soviet Cosmonaut Valentina Tereshkova, the first woman in space, on her arrival at London airport on Tuesday morning, Feb. 4, 1964.
She spent nearly three days in orbit in June 1963. She had to overcome a host of problems during the flight, which were not revealed until after the collapse of the Soviet Union. She remains the only woman to have carried out a solo mission.
Iconic footage of Sergei Korolev, the father of the Soviet space program talking on the radio with first Cosmonaut Yuri Gagarin is shown on a screen at the Museum of Cosmonautics in Moscow, Russia, Oct. 2, 2017.
Chief Soviet rocket engineer Korolev clocked up successes from the launching of Sputnik 1 to Gagarin's historic flight. His role was only disclosed after his death in 1966.
Soviet leaders and fellow cosmonauts carry the ashes of Soviet cosmonaut Vladimir Komarov in the funeral procession in Moscow, Russia, April 26, 1967.
Komarov became the first person to die in space on April 23, 1967 after a 26-hour flight on Soyuz 1. A parachute failed on reentry, causing his craft to plummet to Earth.
This May 1961 file photo shows astronauts Alan Shepard, John Glenn and Virgil I. Grissom.
The first American in space, Shepard's flight on Freedom 7 on May 5, 1961 was suborbital, rising to an altitude of 116 miles (186 kilometers). He later commanded the Apollo 14 in 1971 and became the fifth person to walk on the Moon, where he played golf.
The U.S. Sen. John Glenn talks with astronauts on the International Space Station via satellite before a discussion titled "Learning from the Past to Innovate for the Future" in Columbus, Ohio, U.S., May 13, 2003.
As the first American to orbit the Earth in February 1962, he was later elected as a U.S. senator, serving until 1999. In 1998, at the age of 77, Glenn became the oldest person to go into space when he journeyed aboard the space shuttle Discovery.
Sally Ride, the first American woman in space, is seen in Reno, Nevada, U.S., May 13, 2003.
In June 1983, Sally Ride became the first American woman to be sent into space, on the space shuttle Challenger. She also took part in a 1986 commission that investigated the loss of the vessel. She died of cancer aged 61 in 2012.
Apollo 11 astronauts, Neil Armstrong (L) Michael Collins (C) and Edwin "Buzz" Aldrin smile as they answer questions from quarantine in an isolation unit aboard the USS Hornet after splashdown and recovery on July 24, 1969.
Armstrong was the first human to set foot on the Moon on July 20, 1969. Despite slightly fluffing his line – "That's one small step for (a) man, one giant leap for mankind" – it has since been etched in history. His fellow crewmembers were Edwin "Buzz" Aldrin, who followed 20 minutes later, and Michael Collins, who remained alone in lunar orbit.
This combination of photos made available by NASA shows the 12 men who have walked on the moon. The top row shows men who took part in the Apollo 11 and 12 mission launched in 1969, from the left, Neil Armstrong, Edwin "Buzz" Aldrin, Charles "Pete" Conrad and Alan L. Bean. The middle row shows all those who took part in Apollo 14 and 15 in 1970, from the left, Alan Shepard, Edgar D. Mitchell, David Scott and James B. Irwin. The bottom row shows the crewmembers from the 1972 missions Apollo 16 and 17, from the left, John Young, Charles M. Duke Jr., Eugene A. Cernan and Harrison "Jack" Schmitt.