Second Encounter of Ulysses With Jupiter

Between November 2003 and April 2004, the Ulysses spacecraft will again be in the proximity of Jupiter creating an opportunity for more in-situ and correlated remote -sensing observations. The first encounter in February 1992 took place at a distance of closest approach of 6 Jupiter radii (Rj) and changed the inclination of the Ulysses trajectory so that it would pass above the sun's polar regions. Twelve years later, Jupiter has returned to near its previous location and Ulysses is again approaching aphelion near the orbit of Jupiter at 5.3 AU. This encounter is at much larger distances and Ulysses does not enter, but remains upstream of, the Jovian magnetosphere. However, the spacecraft travels from high to low Jovigraphic latitudes and covers a wide range of local times. On 19 November 2003, the Jovigraphic latitude is 75.5 deg at a distance of 2128 Rj and a local time (LT) near noon. The closest approach of 1683 Rj occurs on 4 February 2004 at 49.5 deg latitude near 17 hours LT. The formal encounter ends on 1 April 2004 at 1926 Rj, a latitude of 21.5 deg and a LT near 17:30. Jupiter is a prolific source of radio waves, energetic charged particles, dust and neutral gas, all of which can be detected by Ulysses. Simultaneous measurements of the solar wind and magnetic field will provide the nearly instantaneous conditions affecting Jupiter's magnetosphere and influencing the production of these emissions. Remote sensing observations by other missions or observers are encouraged to investigate the effect of changing solar wind conditions and structures on Jupiter's dynamic magnetosphere.