What was the name of the first US satellite, launched 31 Jan 1958?
Explorer-1 1958-001A Explorer 1 Satellite 1958 Alpha Explorer I 1958 Alpha 1958 Alpha 1 Explorer-I Explorer1
explorer i 1958 alpha 1 explorer1 satellite 1958 alpha explorer 1 1958 alpha 1958 001a
explorer 1
WikipediaEntity
Explorer 1