Ulysses, a joint European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) mission, was launched on Oct. 6, 1990 by the NASA shuttle Discovery. The probe's primary mission is to investigate the heliosphere out of the ecliptic, a region of space previously unexplored by in situ spacecraft. Ulysses will reach heliographic latitudes of 80° while studying the north and south poles of the Sun. In order to escape the ecliptic plane, Ulysses made a close fly-by of Jupiter on Feb. 8, 1992, to take advantage of that huge planet's gravitational field. This also provided an opportunity for the scientific instruments onboard to sample the Jovian magnetosphere, expanding on measurements taken by the earlier Pioneer and Voyager space probes.
Recently, Ulysses was granted an extended mission which will take it back to Jupiter. After another swingby, Ulysses will return to the solar poles in 2000 (as the sun reaches "solar maximum").