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Ever since the Russians put the first crewed spacecraft in orbit around the Earth and the Americans made their historic landing on the surface of the Moon, the technologically advanced countries of the world engaged in attempts to penetrate the vast expanse of outer space.

Scientists and engineers working together constantly designing new and better space vehicles. The target destinations for these vehicles the neighbouring planets in our Solar System, such as Mars and Mercury. So far, the main obstacles to space travel remain the great distances between these planets and Earth. The millions of miles of cold and empty space would take a very long time to traverse, and this would raise the question of how to support life on board these space crafts as space a vacuum devoid of life-giving oxygen. To date, scientists only able to send unmanned crafts to these planets. The sole purpose of these missions to gather information through aerial photographs and the testing of surface materials transmitted back to Earth via radio waves.

Another obstacle to space travel the prohibitive cost of such undertakings. The advent of the space shuttle lowered the cost factor by allowing the same vehicle to be used repeatedly. The Shuttle can carry passengers and cargo, and after completing its mission in space, it lands back on Earth much like a conventional aircraft. It often launched into space on the back of a rocket or a large jet plane.

Many experts believe that Man so ravaged mother Earth that she may not recover. The damage caused to the environment by pollution, the changing climates on Earth, the depletion of the ozone layer, and the phenomenon of global warming due to atmospheric carbon dioxide increases all brought about in one way or another by man. As a result, experts feel that it may be time that we start looking to space for some of the solutions to our problems.

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