On October 4, 1957, the Soviet Union launched the earth's first artificial satellite, Sputnik I. The successful launch came as a shock to experts and citizens in the United States, who had hoped that the United States would accomplish this scientific advancement first. The fact that the Soviets were successful fed fears that the U.S. military had generally fallen behind in developing new technology. As a result, the launch of Sputnik served to intensify the arms race and raise Cold War tensions
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