Exploration of Jupiter Exploration of Jupiter The exploration of Jupiter has been conducted via close observations by automated spacecraft. It began with the arrival of "Pioneer 10" into the Jovian system in 1973, and, , has continued with eight further spacecraft missions. All of these missions were undertaken by the National Aeronautics and Space Administration (NASA), and all but two have been flybys that take detailed observations without the probe landing or entering orbit. These probes make Jupiter the most visited of the Solar System's outer planets as all missions to the outer Solar System have used Jupiter flybys to reduce fuel requirements
Exploration of Jupiter probe, en route to Pluto, flew by Jupiter for a gravity assist and was the first probe launched directly towards Jupiter since the "Ulysses" in 1990. Its Long Range Reconnaissance Imager (LORRI) took its first photographs of Jupiter on September 4, 2006. The spacecraft began further study of the Jovian system in December 2006, and made its closest approach on February 28, 2007. Although close to Jupiter, "New Horizons" instruments made refined measurements of the orbits of Jupiter's inner moons, particularly Amalthea. The probe's cameras measured volcanoes on Io, studied all four Galilean moons in detail, and made long-distance studies