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Man on the moon! - A famous speech given by John F. Kennedy in the early 1960s promised that, by the end of the decade, American astronauts would set foot on the moon.

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Conquering the Moon - What seemed a far off dream became reality in 1969: man had already reached space and one of the greatest feats of the space age was about to happen.

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Historic achievement - It was the Apollo mission which took a man to the moon for the very first time. The images of the spaceship flying over the surface of the moon became iconic.

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Mission -

But before arriving at this historic moment, the Apollo mission went through a terrible tragedy.

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Tragedy - During a launch test for Apollo 1, the cockpit caught fire, killing Edward White, Virgil Grissom, and Roger Chaffee.

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Theory - There is a conspiracy theory which questions whether humans ever really made it to the moon, or if the whole scene was filmed in a studio. One thing is certain: the tragedy went down in history.

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Soyuz 1 - Another terrible incident occurred in 1967 with a Soviet spaceship.

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The mission - Soyuz 1 took off from a Soviet base. Its mission was to circle the Earth and change crews with another ship that was already in Space: Soyuz 2. Cosmonaut Vladimir Komarov, however, said that there were several technical problems and so the mission was aborted.

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The accident - On returning to Earth, Vladimir Komarov tried to release the parachutes to slow down the vessel's return to the ground, but the attempt failed.

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Tragedy - The spaceship hit the ground at a speed of approximately 140 km per hour, killing its pilot.

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Vladimir Komarov - The tragedy earned Komarov numerous posthumous tributes.

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Soyuz 11 - Another tragedy struck Soviet Space project in 1971, with the spaceship Soyuz 11.

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Crew - The crew of Soyuz 11 was made up of Georgi Dobrovolski, Viktor Patsayev, and Vladislav Volkov, who had been in space for about 23 days and were returning to Earth.

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Tragic return - The crew began the procedure to re-enter the atmosphere, and appeared to have done it perfectly. However, once the ship had landed and been opened, the crew were found mysteriously dead.

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Investigation - Their deaths were explained by a fault in the ventilation valve, which made their capsule completely depressurize while in Space.

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Greif -

The ship had only managed to re-enter the Earth's atmosphere thanks to the automatic pilot. The deaths of the three cosmonauts caused much grieving in the Soviet Union.

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Challenger - The Challenger accident of 1986 is one of the most famous incidents of all.

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Crew - The crew who prepared to set off on the mission were: Greg Jarvis, Ronald McNair, Ellison Onizuka, Judith Resnik, Michael J. Smith, D i c k  Scobee, and Christa McAuliffe.

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New passenger - This NASA mission was unique as it was the first time that a civilian had the chance to travel to space. Teacher Christa McAuliffe was part of the team of astronauts.

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Live transmission - In January 1986 all eyes were on the launch of this space shuttle, which was broadcast live on TV.

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Tragedy - About 72 seconds after the launch, a tragedy occurred as viewers watched.

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Causes of the accident - The shuttle exploded due to an instability in the fuel tank insulation after it was exposed to colder temperatures.

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No survivors - The entire crew were killed in the explosion.

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Fight - NASA paused its space program for two years while it searched for ways to prevent tragedies like Challenger from happening again.

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Columbia - Another fatal accident occurred in 2003 with spaceship Columbia.

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Accident - After 16 days in orbit, the space shuttle disintegrated on its return to Earth.

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Crew - There were seven crew members: Rick D. Husband, William McCool, Michael P. Anderson, David M. Brown, Kalpana Chawla, Laurel B. Clark, and Ilan Ramon. None of them survived the accident.

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Cause of the accident - An investigation later discovered that the cause of the accident was a rupture in the heat insulation foam on one of the wings during launch.

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Exploring the universe -

These tragic incidents remind us of the fragility of human life in our pursuit for the meaning of the world and the origins of the universe.

See also: https://www.starsinsider.com/lifestyle/505656/the-stellar-women-who-revolutionized-space-travel

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