The Soviet Union launched the satellite, Sputnik 1.
The Sputnik satellite was sent into orbit by the USSR on October 4, 1957. The Soviets announced its mission as a scientific one, to study the solar system. In the Cold War atmosphere, of course, Americans were wary of what other motives the USSR might have had. The Soviets launched Sputnik 2 in November, 1957, with a dog on board. The USA scrambled to get its own satellite program operational, launching the first US satellite, Explorer, on January 1, 1958.
