Sunday, July 13, 2008

This Really Is Rocket Science

While spaceflight was the subject of many centuries of speculation, three men worked independently to lay its practical foundation. Konstantin Eduardovich Tsiolkovsky (1857–1935) was a lonely Russian boy, almost totally deaf, who grew up in retreat with his books. He became a provincial schoolteacher, but his consuming interest was flight, and he built a wind tunnel to test various aircraft designs. Soon he became even more fascinated by the thought of space travel, producing the first serious theoretical books on the subject during the late nineteenth and early twentieth centuries.

Another quiet, introspective boy, this one a New Englander, Robert Hutchings Goddard (1882–1945), was captivated by H. G. Wells’s science-fiction novel War of the Worlds, which he read in an 1898 serialization in the Boston Post. On October 19, 1899 (as he remembered it for the rest of his life), young Goddard climbed a cherry tree in his backyard and “imagined how wonderful it would be to make some device which had even the possibility of ascending to Mars.” From that day, the path of his life became clear to him. Goddard earned his Ph.D. in physics in 1908 from Clark University in his hometown of Worcester, Massachusetts, and, working in a very modest laboratory, he showed experimentally that thrust and propulsion can take place in a vacuum (this follows from Newton’s Laws of motion—the expelled gases pushing forward on the rocket). He also began to work out the complex mathematics of energy production versus the weight of various fuels, including liquid oxygen and liquid hydrogen. These are the fuels that would ultimately power the great rockets that lofted human beings into orbit and to the moon—and still power the launch of many rockets today. Goddard was the first scientist to develop liquid-fuel rocket motors, launching the inaugural vehicle in 1926, not from some governmental, multimillion-dollar test site, but from his Aunt Effie’s farm in Auburn, Massachusetts. Through the 1930s and 1940s, he tested increasingly larger and more powerful rockets, patenting a steering apparatus and the idea of what he termed “step rockets”—what would later be called multistage rockets—to gain greater altitude.

Goddard’s achievements were little recognized in his own time, but, in fact, he had single-handedly mapped out the basics of space-vehicle technology, including fuel pumps, self-cooling rocket motors, and other devices required for an engine designed to carry human beings, telecommunications satellites, and telescopes into orbit. Hermann Oberth (1894–1989), born in Austria, was destined for a medical career, like his father, but his medical studies were interrupted by World War I. Wounded, he studied physics and aeronautics while recovering. While he was still in the Austrian army, he performed experiments to simulate weightlessness, and designed a longrange, liquid-propellant rocket. The design greatly impressed Oberth’s commanding officer, who sent it on to the War Ministry, which summarily rejected it. After the war, University of Heidelberg faculty members likewise rejected Oberth’s dissertation concerning rocket design. Undaunted, Oberth published it himself—to great acclaim—as The Rocket into Interplanetary Space (1923). In 1929, he wrote Ways to Spaceflight, winning a prize that helped him finance the creation of his first liquidpropellant rocket, which he launched in 1931.
During World War II, Oberth became a German citizen and worked with Wernher von Braun to develop rocket weapons.

No comments: