Juno II

Juno 2

Mission Profile

The Juno II was a four-stage American launch vehicle derived from the Army's Jupiter IRBM, developed to extend the capabilities of the smaller Juno I rocket with a more powerful first stage for heavier scientific payloads. Standing 24 m tall with a 2.7 m diameter and a liftoff mass of 55,200 kg, it generated 667 kN of thrust from its Jupiter first stage. First flying in December 1958 as part of the Explorer program, the Juno II launched several early American scientific satellites including Pioneer 3 and Pioneer 4, though its operational career was brief as larger rockets quickly superseded it.