Of all the accomplishments of the twentieth century, one stands out as the greatest: flight and the beginning of the exploration of space. Within the span of a human's lifetime, the unbelievable happened. On December 17, 1903, the Wright Brothers first flew an airplane at Kitty Hawk, NC. Sixty-five years after Kitty Hawk, a human being stepped out onto another world.
It was as Carl Sagan said in 1970, "In all the history of mankind, there will be only one generation which will be the first to explore the solar system, one generation for which, in childhood the planets are distant and indistinct discs moving through the night, and for which in old age the planets are places, diverse new worlds in the course of exploration. There will be a time in our future history when the solar system will be explored and inhabited by men who will be looking outward toward the first trip to the stars. To them and to all who come after us, the present moment will be a pivotal instant in the history of mankind." (Burrows, p.ix)