The Jupiter missile was proposed as a suborbital launch vehicle for Project Mercury in October, 1958; however, it was never flown, and was cancelled in July 1959 due to budget constraints. It would have been capable of launching the Mercury spacecraft to a 300 mile (500 km) apogee at 10,000 mph (14,000 km/h) and 1,500 miles (2,500 km) downrange. However, when this trajectory was used on earlier biological test flights, the animals received 40 g during reentry, so perhaps the Jupiter would not have been used to its full capability on manned flights.

Planned manned Mercury launch vehicles