HR: 0800h
AN: GP31A-0823    [Abstracts]
TI: Estimation Of Field-Aligned Currents With A Multi-Satellite Mission ({\it Swarm})
AU: * Ritter, P
EM: pritter@gfz-potsdam.de
AF: GeoForschungsZentrum Potsdam, Telegrafenberg, Potsdam, 14473 Germany
AU: L\"uhr, H
EM: hluehr@gfz-potsdam.de
AF: GeoForschungsZentrum Potsdam, Telegrafenberg, Potsdam, 14473 Germany
AB: The multi-satellite mission Swarm is conceived to investigate the dynamics of the Earth's magnetic field and its interaction with the Earth system in unprecedented detail. The instrumentation on board will provide high precision vector data of the electric and magnetic fields. For a further improvement of the main field and lithospheric field models it is vital to understand and reduce the influence of ionospheric currents. With the planned constellation of two satellite pairs at different heights, one at 550 km and the other at initially 450 km, the mission is particularly well suited to study the complex current systems of the polar ionosphere. The lower pair shall fly side-by-side separated by only $\sim$100 km in east/west direction. This will allow for the first time to determine ionospheric field-aligned currents unambiguously by directly employing the curl-{B} relation. As part of an {ESA}-funded science study auroral current systems were generated by one of the global {MHD} codes of the {GGCM} covering different degrees of activity. The new technique is applied to this set of consistent magnetic field and current data. By using realistic satellite trajectories and instrument performances we recovered the field-aligned current distributions from the magnetic field deflections. The resulting currents are tested against the input currents. The agreement between input model and recovered field-aligned currents is satisfying and much improved compared to the single-satellite estimates. These investigations demonstrate one important aspect of the broad capabilities provided by the unique new space mission project.
DE: 2407 Auroral ionosphere (2704)
DE: 2409 Current systems (2708)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 1500 GEOMAGNETISM AND PALEOMAGNETISM
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2004 AGU Fall Meeting