NASA's upper-stage rocket used to lift heavy satellites and space probes in combination with the Atlas rocket and the Titan rocket. The US Air Force developed the liquid-hydrogen and liquid-oxygen engine for the first Centaur in 1958. The rocket's deployment of deep-space probes has included the two Voyager probes in 1977, when the Centaur's sophisticated computer flew each spacecraft into low orbit, calculated the flight path and velocity, then shut off the rocket engines and separated as Voyager headed for Jupiter.