The year was 1898. The place was the small Russian town of Kaluga, about one hundred miles southwest of Moscow. The man was a deaf, forty-one-year-old arithmetic teacher named Konstantin Eduardovich Tsiolkovsky who calculated precisely how human beings could depart the Earth to explore other worlds. The fact that Tsiolkovsky made these calculations entirely on his own with only a vague awareness of innovations occurring elsewhere made his feat all the more amazing.
Tsiolkovsky lost his hearing at the age of nine, which disposed him throughout his life to keep mostly to himself. He developed an interest in math and physics as a child, and as a teenager he was already dreaming of space. After three years of studying chemistry, math, astronomy, and mechanics at the university in Moscow, Tsiolkovsky left, at his father's request, to support himself as a school teacher. He never gave up his interest in aeronautics and astronautics, however, and, even though he was cut off from scientific centers, he did innovative and important work in aerodynamics.
Over the years, Tsiolkovsky's interest in problems of space travel increased. Ultimately he conceived a device he came to call a "reaction machine"Ña liquid-fuel rocket ship that could be used to propel humans beyond Earth.
This machine was only the beginning of an uncannily accurate vision Tsiolkovsky had of the future. He believed that someday the human race would scatter across the Milky Way, and he correctly predicted that in the process we would build self-sustaining space stations, explore the Moon, and design space suits, earth-orbiting solar power stations, and artificial gravity machines. He imagined a time when humans would re-engineer the environments of other planets, populate the asteroid belt beyond Mars, and communicate with extraterrestrial beingsÑall ideas that would become centerpieces of 20th- and 21st-century space exploration.
