Explorer 1

Explorer 1 was the first satellite launched by the United States and was part of the U.S. participation in the International Geophysical Year (IGY). The 1958 mission followed the first two satellites, both launched by the Soviet Union during the previous year, Sputnik 1 and Sputnik 2. This began a Space Race during the Cold War between the two nations. Explorer 1 was launched on 1 February 1958 at 03:47:56 GMT (or 31 January 1958 at 22:47:56 Eastern Time) atop the first Juno I booster from LC-26A at the Cape Canaveral Missile Test Center of the Atlantic Missile Range (AMR), in Florida. It was the first spacecraft to detect the Van Allen radiation belt, returning data until its batteries were exhausted after nearly four months. It remained in orbit until 1970. Explorer 1 was given Satellite Catalog Number 00004 and the Harvard designation 1958 Alpha 1, the forerunner to the modern International Designator.