The Ulysses spacecraft was built by ESA and was not intended for planetary observations. However, it did record data covering fields and particles about Jupiter in the early 1990s and so is included here for completeness. Ulysses was launched on October 6, 1990 by the space shuttle Discovery (STS-41) and its mission was to
observe the magnetic field and plasma environment in the solar wind from above the poles of the Sun. To achieve this viewing position, Ulysses flew first to Jupiter and made a gravity assist flyby maneuver on February 8,1992, which placed it into a high-inclination, highly eccentric orbit about the Sun. It passed over the Sun's South Pole in 1994 and then its North Pole in 1995. The most recent passes over the Sun's South and North Poles took place in 2000/2001 and again in 2007/2008. However, although Ulysses' mission was extended until March 2009 the power output from the spacecraft's RTG steadily declined and in July 2008 mission operations formally ceased due to the freezing of the spacecraft's attitude control fuel, hydrazine.
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