Fifty years after the Apollo 11 mission, it was revealed in a BBC drama documentary – 8 Days: To the Moon and Back – that astronauts were supposed to fly backwards. It says: "When they start their approach, the Lunar module will turn 180 degrees. With the back to the moon, astronauts will fly blind. "
In extraordinary audio recordings of the spacecraft, one of the astronauts can be heard chanting, "He fixed the Earth from the front window!"
In 1973, the total cost of the Apollo program was reported to Congress as $ 25 billion, about £ 20 billion or £ 323 billion in today's money.
Not only did the mission cost a huge amount, it was the culmination of decades of hard work by thousands.
As a result, there was a lot of pressure on the pilots to succeed.
READ MORE Moon: Lunar Landing: Armstrong and Aldrin Almost Captured on the Moon
Flying backwards was not the only difficulty Commander Armstrong and Lunar Module pilot Booz Aldrin faced.
When they turned the Lunar module, they realized that they were flying long and might miss the landing spot.
Then, just minutes away, the program started to sound an alarm that astronauts had never met in training.
Mr. Armstrong radio went down in control of the Mission in Houston, Texas and asked, "Give us a read on the alarm for the 1202 program."
Mr. Armstrong and Mr. Aldrin were alone in the Lunar module, named the Eagle, and had only one chance to land or the entire mission would have to be aborted.
At one point, they had only 60 seconds to land the plane or head home unsuccessfully.
As one presenter said at the time: “The hard part is getting close to it, and then having to devote yourself to all this work.
"And I think the pressure is probably the biggest pressure the crew will ever have."
Fortunately, they successfully landed on the surface of the moon.
Mr. Armstrong climbed the lunar surface ladder and uttered the familiar words: "One small step for man, one giant leap for mankind."
Then, they had more than two hours to photograph and sample, as well as a brief conversation with US President Richard Nixon.
Then, they got off the moon and joined their colleague Michael Collins in the command module and flew back to Earth.