After World War II, the United States pitted its resources against the Soviet Union in a Cold War that lasted for forty years. By the 1950s, the battlefield for the Cold War had extended into outer space. The USSR claimed the first victory when it launched the satellite Sputnik in 1957. Humiliated, the USA redoubled its efforts and organized NASA to propel space exploration onward--and before the Russians. NASA's progress was impressive (but not necessarily constant). By 1969, NASA had placed a man on the moon. Barren as it was, the moon encouraged exploration of life on other heavenly bodies. In the early 1970s, NASA launched the Viking series of spacecraft, like this model, to record the surface of Mars. The initial photographs returned from Mars disappointed those who had hoped to find life on the planet. In spite of such a setback, exploration of Mars continued.