Tsiolkovsky is often called the 'father of astronautics' because of his pioneering studies of the feasibility and practicality of space flight. He was born on September 17, 1857, at Izhevskoye, a town to the south-west of Moscow. By the age of 15, now deaf following an illness, he had developed a consuming passion for rocketry, then in vogue with the Russian army. He was only 21 when he first suggested that rockets might be used to launch objects into space. He developed the theme as time went by. By 1883 Tsiolkovsky was a schoolteacher, and in that year wrote a book ('Free Space'), in which he quite accurately predicted the state of weightlessness in space. In 1894 he moved to Kaluga, where he spent the rest of his life. It was there that he refined his theories about space travel, which led him in 1903 to publish a paper entitled 'Exploring Space with Reactive Devices'. It was the first publication to set down many of the principles on which astronautics, or space flight, depends. In his paper Tsiolkovsky stated that only reactive devices - that is, rockets - could be used for propulsion in space, and that a much more powerful propellant than gunpowder would be required. He suggested a combination of liquid hydrogen and liquid oxygen, exactly the propellants used now in the space shuttle and the Soviet monster rocket Energia. He also realized that a launch vehicle would need to be made up of several rockets joined together to boost an object into space. In other words he elaborated the principle of the step rocket. All this and more about travelling in space, Tsiolkovsky set down in his paper, which appeared even before the Wright brothers had mastered the art of travelling in the air in an aeroplane! He died on September 19, 1935.
