The base of the jovial groove as the little group walked was a lilting, repeating riff on the kora, the 21-string harp-lute that a musician played with its base propped against his torso, plucking with his thumbs. â
The Vanguard team was still working on a test vehicle (TV-2) designed to test the first stage of the rocket when they learned of the launch of the world's first artificial satellite, Sputnik I, by the USSR on October 4, 1957. On December 2, the Department of Defense announced the imminent launch of TV-3.
Explorer 1 became the first successfully launched satellite by the United States when it was sent to space on January 31, 1958. A quick response to the Soviet Union's launch of Sputnik 1, Explorer 1's success marked the beginning of the U.S. Space Age.