The Vanguard rocket was developed by the Naval Research Laboratory for the purpose of launching a satellite for the International Geophysical Year (1957-1958).

The first stage of the Vanguard was an improved version of the earlier Viking sounding rocket. A second and third stage were added to allow a payload to be placed in orbit. After the Soviet Union scored the first win in the "Space Race" by orbiting Sputnik on October 4, 1957, the Vanguard Project was to be America's reply.

The first two launch attempts were unsuccessful. On December 6, 1957 the first attempted launch ended in fiery failure, prompting newspaper headlines of "Kaputnik", "Stayputnik", and the like. The second attempt on February 5, 1958 also ended in failure. The first successful launch on March 17, 1958 lofted the Vanguard I satellite into orbit. The 6.4-inch 3.5-lb. satellite, though derided by Soviet Premier Nikita Kruschev as a "grapefruit", provided scientists with much useful information. Though the transmitter fell silent in 1964, the satellite is still in orbit.