Page "Juno I" Paragraph 2

The September 1956 test launch of a Jupiter-C for the Army Ballistic Missile Agency could have been the world's first satellite launch.

Had the fourth stage been loaded and fueled, the nose cone would have overshot the target and entered orbit.

Such a launch did not occur until early 1958 as part of Project Vanguard, after the Soviet Union's Sputnik 1 in October 1957.