This image, drawn in 1970, is an artist's rendering of the Pioneer 10 spacecraft trajectory, with the planets labeled and a list of the instruments that were intended to be flown. Before the use of computer animation, artists were hired by JPL and NASA to depict a spacecraft in flight, for use as a visual aid to promote the project during development. Pioneer 10 was managed by NASA Ames Research Center in Moffett Field, California. The Pioneer F spacecraft, as it was known before launch, was designed and built by TRW Systems Group, Inc. JPL developed three instruments that flew on the spacecraft: Magnetic Fields, S-Band Occultation, and Celestial Mechanics; as well as running the Deep Space Network which provided tracking and data system support. Caltech was responsible for the Jovian Infrared Thermal Structure experiment. Pioneer was very successful, crossing the orbit of Mars and the asteroid belt beyond it; encountering, studying, and photographing Jupiter; then crossing the orbits of Saturn, Uranus, and Neptune. It left the solar system in 1983 and has been contacted several times in the past few years. As of July 2001, the spacecraft was still able to send a return signal to Earth. At Jupiter, the experiments of Pioneer were used to examine the environmental and atmospheric characteristics of the giant planet. Pioneer was also the vital precursor to all future flights to the outer solar system. It determined that a spacecraft could safely fly through the asteroid belt. It also measured the intensity of Jupiter's radiation belt so that NASA could design future Jupiter (and other outer planets) orbiters.