Manned spaceflights carried out by the NASA Introduction Since mankind had begun to perceive its surroundings, the sun, the Moon and the stars played an important role in its evolution. Religions were based upon stars, magician predicted the future because of astronomical constellations and emperors compared themselves to the sun. The universe conveyed the impression of something giant, powerful, infinite and untouchable, so to speak, it was an object of interest. Throughout the centuries the attitude towards the cosmos changed, because people changed. At the beginning, primitive tribes as well as sophisticated cultures adored the stars, and were convinced, that the Earth was in the middle of the universe. Later, Galleleo Gallelei said, that it was the other way around, and therefore he was persecuted by the Christian Church. Whatever people thought of the universe, they always dreamed of reaching out for the stars. They climbed up mountains, to be nearer to the stars and they believed, that there was a man, sitting on the Moon and extraterrestrials on the Mars. Even the French author Jules Verne wrote in his novel "Journey to the Moon", that a few men are shot on the Moon with a giant canon-bullet. This was in the 19th century. His fellows laughed at him, and announced him nuts or at least a dreamer. But within the our century, things changed. Scientific progress made it possible, to transport objects and even men - of course men and women - away from Earth, up to the sky. Life couldn?t be the way it is, if we wouldn?t have satellites for communication, observation and other important sectors. All this requires flights into the space. Although unmanned missions are the biggest part of space-flights, they are not nearly as spectacular, popular and exciting as manned missions. Think of the millions of people, who watched Neil Armstrong, stepping down the Eagle and setting his foot on the Moon or the world-wide shock after the Challenger-disaster. Even in the cinema, the men in space attract the audience, for instance, films like Apollo 13 or Star Trek. Manned space-travel always fascinated people and millions of children dreamed of becoming an Astronaut. In the following chapters I want to give a (small) insight of the fascination "manned space-travel", limited to the US space-flights. History of rockets and the competition between the USA and the USSR In the 13th century, Chinese scientist invented a powder, which exploded, when it came in contact with fire. A hundred years later, a monk named "Berthold der Schwarze" invented a similar substance: the "Black powder". The Chinese were the first, who constructed basic rockets and used them at the siege of cities. Until the beginning of this century, some improvement were made, but in the principle, the rocket was the same as ever: unreliable, limited to a small payload and small ranges, and it seldom hit the target. At the end of the 19th century, the Russian physicist Konstantin Eduardowitsch Ziolkowskij suggested, to use them as space-ships, and he was promptly derided. After the First World War, in which rockets were hardly used, scientists and military personal started working on rockets, which were powered by liquid substances.
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