Jupiter-A

The Redstone family of rockets consisted of a number of American ballistic missiles, sounding rockets and expendable launch vehicles operational during the 1950s and 1960s. The first member of the family was the PGM-11 Redstone missile, from which all other members were derived. The first large U.S. rocket, modified Redstones launched America's first Earth satellite and first two astronauts. They were named for the Redstone Arsenal in Huntsville, Alabama where it was developed.

First launched in 1953, the PGM-11 Redstone was a short-range surface-to-surface ballistic missile in active service with the U.S. Army from June 1958 to June 1964; and was used for the first U.S. live nuclear missile tests. It was built by Chrysler for the United States Army Ballistic Missile Agency (ABMA) and was deployed in West Germany.

Jupiter-A was the first variant of Redstone, used to test components later used in the PGM-19 Jupiter medium-range ballistic missile.

Jupiter-C was a sounding rocket used for three sub-orbital spaceflights in 1956 and 1957. It was used as a testbed for re-entry vehicles later deployed on the PGM-19 Jupiter.

Juno I was a derivative of the Jupiter-C, used to launch the first American satellite, Explorer 1, on January 31, 1958. Although the U.S. possibly could have put a satellite into orbit before the Soviet Union had the ABMA been allowed to attempt a satellite launch in August 1956, the Eisenhower administration wanted the first U.S. satellite to be launched by a civilian-developed rocket instead of a military missile derivative.

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