Heliophysics Science Division
Sciences and Exploration Directorate - NASA's Goddard Space Flight Center

May 28, 2010, 12:00 pm - 1:00 pm

May 28, 2010, 12:00 pm - 1:00 pm

Jupiter’s Magnetotail: Plasma Composition and the Location, Structure and Dynamics of its Dusk Flank Boundary



Robert W. Ebert (University of Texas at San Antonion, SWRI)

New Horizons (NH) was launched in early 2006 with its primary mission being a reconnaissance flyby of Pluto and its moons in 2015 (Stern 2008). Its interplanetary cruise included a gravity assist flyby of Jupiter that provided an opportunity to explore the Jovian magnetosphere in 2007. NH entered Jupiter’s dayside magnetosphere at 67 RJ on DOY 56, 2007 and proceeded on a trajectory nearly directly down the Jovian magnetotail, including the previously unexplored ~-150 to -2550 RJ tail region. Here, we will discuss observations of this unexplored tail region from the Solar Wind Around Pluto (SWAP) instrument onboard NH. SWAP was designed to measure the solar wind plasma (typically >90% H+, <10% He++, and only trace: <<1% heavier ions) to beyond the orbit of Pluto over an energy per charge (E/Q) range of 0.035 to 7.5 keV/Q (McComas et al. 2008). We have pursued further analysis of the instrument response, characterizing it for different mass ions, with the goal of determining the plasma composition in Jupiter’s magnetotail. In this talk, we present our analysis of SWAP’s mass-dependent response, including a technique developed to distinguish between light and heavy ions measured by the instrument, and our studies on the composition of the low energy (< 7.5 keV/Q) plasma in Jupiter’s magnetotail and the location, structure and dynamics of its dusk flank boundary.