HR: 16:25h
AN: SM24A-02 INVITED     [Abstracts]
TI: Generation of Global Auroral Morphology at Earth and Jupiter
AU: * Hill, T W
EM: hill@rice.edu
AF: Rice University, MS108, Houston, TX 77005 United States
AB: Global patterns of auroral morphology at Earth and Jupiter have superficial similarities but very different causes. In both cases, the brightest auroras are produced by downward-accelerated magnetospheric electrons carrying upward Birkeland (magnetic-field-aligned) currents. And in both cases, the resulting global auroral morphology is an oval. But the mechanisms that drive the upward Birkeland currents are very different in the two cases. At Earth, the upward currents are part of a complex solar-wind-magnetosphere interaction in which the upward Birkeland currents on the dusk side are part of the driving "Region-1" current system but those on the dawn side are part of the responsive "Region-2" current system. At Jupiter, the upward currents are part of a circuit that enforces partial corotation of magnetospheric plasma that is continually produced and transported outward within the magnetosphere, with no obvious solar-wind influence and hence no obvious dawn-dusk asymmetry.
DE: 5737 Magnetospheres (2756)
DE: 2409 Current systems (2708)
DE: 2704 Auroral phenomena (2407)
DE: 2736 Magnetosphere/ionosphere interactions
DE: 2756 Planetary magnetospheres (5443, 5737, 6030)
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting