NASA landed the first human on the lunar surface on July 20, 1969, half a century ago this year. The monumental successes led to the astronauts Neil Armstrong, Michael Collins and Buzz Aldrin successfully flew to the moon, landed and returned to Earth. The moon landing was the greatest achievement of the 20th century, but the Apollo program was anything but smooth from start to finish. Above all, the crew of Apollo 1 – the first manned Apollo mission – died in a starting test in a tragic cabin fire.
And the many astronauts flying into space under the banner of NASA risked their lives each time they blasted off the earth.
Professor Craig Underwood of the Surrey Space Center at the University of Surrey spoke with Express.co.uk about the incredible courage and determination of NASA astronauts.
The majority of NASA crews in the Gemini, Mercury, and Apollo programs had background in aviation and test flights with military and experimental aircraft.
For that reason, the astronauts were outsiders in the field of spaceflight, who could face death calmly every day.
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Professor Underwood said, "They worked in ways we could not have thought of today.
"The test pilots died massively in the 1960s, not just in the US but also in the UK.
"We find that absolutely terrible today, but they were ready to take those risks and drive progress. "
Commander Armstrong was a naval aviator in the Korean War before he joined NASA and was a test pilot for the experimental X-15 rocket plane.
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The future Apollo 11 commander was killed for the first time in 1951 when his Panther jet fighter was struck by enemy fire over Korea.
The Test Pilots Died Very Quickly in the 1960s
Then in 1957 he flew the experimental Bell X-1B, which crashed when his landing gear failed to deploy properly and disintegrated.
Just a few years later, in 1962, the X-15 rocket-propelled aircraft flew over the Earth's atmosphere at the edge of space, nearly landing on Armstrong in space.
Luckily, the astronaut's famous nerves slammed from steel and allowed him to fly a trajectory that pulled him down to the ground again.
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Professor Underwood said, "The X-15 was a massive plane exploring the borders of knowledge, flying hypersonally.
"So you were all exceptionally brave people. Of course we lost three astronauts in the fire of Apollo 1 and, ironically, that was a ground test.
"That was a wake-up call, and though tragic, it was an important lesson, and they redesigned it and made it a much safer vehicle.
But Commander Armstrong's near-death experiences did not end there.
The astronaut and his co-driver David Scott make an almost deadly spin over the earth.
Commander Armstrong stabilized the spacecraft and broke off the mission, but approached dangerously the exit from the G-forces exerted by the rotation.
In 1969, just a year before flying to the moon, a training accident with a Lunar Landing Training Vehicle (LLTV) killed Commander Armstr as it crashed.
Fortunately, the pilot crashed out of the falling jet vehicle before spectacularly breaking into a flame ball.
A final fatal blow occurred during the moon landing when Apollo 11's lunar eagle had strayed off course and hit a rock-strewn crater on the moon.
With loud alarms and the navigation computers overfilled on-board computers, Commander Armstrong had to lead the eagle by hand to a free landing site.
The astronaut safely landed in the ocean of calm with less than 30 seconds of fuel.
The rapid descent ended when Armstrong told NASA Mission Control, "Houston, Tranquility Base here. The Eagle has landed.
A total of 18 US astronauts and Russian cosmonauts died in space, with the exception of out-of-space activities such as the tragic Apollo 11 disaster.
Short facts about the Apollo 11 moon landing:
1. NASA launched the Apollo 11 crew on 16 July 1969 into space.
. 2 Michael Collins stayed in lunar orbit while Neil Armstrong and Buzz Aldrin landed on the moon.
. 3 The two astronauts spoke on the lunar surface with President Richard Nixon.
. 4 Buzz Aldrin came to Communion on the Moon – the first to do so.
. 5 Apollo 11 returned to Earth on July 24, 1969.