Robert Goddard.

Robert Hutchings Goddard was born into a family of comfortable means, supported by his inventor-manufacturer father. Robert was sickly as a child and did not graduate from high school until the age of twenty-one. He was later found to have tuberculosis, which would persist throughout his life. On October 19, 1899, when Goddard was seventeen, he had a dream of almost mystical quality about space travel: It was the motivation for his lifework, and he remembered it every year on its "Anniversary Day." He began to work out the mathematical possibilities of rocket engines when he was an undergraduate and took out his first patents shortly after finishing his graduate work. During this time, Goddard also demonstrated that a rocket can function in a vacuum. A popular misunderstanding stated that the rocket could not move in space, with nothing to push "against." In fact, a rocket does not push against anything external. It is like a can with a continuous explosion inside. As long as the can is intact, internal pressure is equal in all directions, and the can does not move. If one end is removed, the pressure falls to zero at that end; the pressure at the other end is unbalanced, and that pressure drives the rocket forward. In fact, Goddard found, the rocket is more efficient in a vacuum, because its own exhaust does not get in the way of the rearward blast. Smithsonian and Guggenheim grants enabled Goddard to work as he liked: alone as a scientist, assisted by only a few technicians. His wife, Esther, a woman of considerable mental ability although untrained in science, acted as his collaborator, scribe, and sounding-board through nearly the whole of his research career. Over three decades, Goddard established almost all the engineering advances of modern rocketry. INSET: Robert Goddard.