FastFind »   Lastname: doi:10.1029/ Year: Advanced Search  

AGU: Journal of Geophysical Research, Space Physics

 

Keywords

  • satellite plasma interaction
  • Enceladus
  • Alfven wing

Index Terms

  • Planetary Sciences: Comets and Small Bodies: Magnetospheres
  • Planetary Sciences: Solar System Objects: Saturnian satellites
  • Planetary Sciences: Fluid Planets: Interactions with particles and fields
  • Magnetospheric Physics: Field-aligned currents and current systems
Abstract
Cited By (10)
 

Abstract

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 112, A11209, 11 PP., 2007
doi:10.1029/2007JA012479

Hemisphere coupling in Enceladus' asymmetric plasma interaction

Joachim Saur

Institut für Geophysik und Meteorologie, Universität zu Köln, Cologne, Germany

Fritz M. Neubauer

Institut für Geophysik und Meteorologie, Universität zu Köln, Cologne, Germany

Nico Schilling

Institut für Geophysik und Meteorologie, Universität zu Köln, Cologne, Germany

The recently discovered neutral gas plume around the south pole of Enceladus introduces a pronounced north-south asymmetry in the plasma interaction of Saturn's magnetosphere with Enceladus. In this work we present an analytic model for such an asymmetric interaction for both an Alfvénic and a unipolar inductor far field model including the Hall effect. We find that even though both hemispheres of Enceladus are not directly connected through magnetic field lines, both hemispheres are electromagnetically coupled, that is, the perturbations of the velocity and magnetic fields generated around the south polar plume are mapped in a modified way into the northern hemisphere. This hemisphere coupling creates surface currents on the magnetic flux tube determined by field lines tangent to the body of Enceladus. The surface currents are accompanied by a magnetic field discontinuity across the flux tube on both hemispheres, that is, a discontinuity across the northern and the southern wings. The Cassini spacecraft has not yet crossed this boundary, which we here predict. The diameter and other properties of the discontinuity are diagnostic of plume properties and might be even diagnostic of electrodynamic induction in a potential subsurface ocean on Enceladus. Our model is also applicable to other satellite plasma interactions where similar asymmetries can occur such as Io or extra solar planets.

Received 17 April 2007; accepted 3 August 2007; published 16 November 2007.

Citation: Saur, J., F. M. Neubauer, and N. Schilling (2007), Hemisphere coupling in Enceladus' asymmetric plasma interaction, J. Geophys. Res., 112, A11209, doi:10.1029/2007JA012479.

Cited By

Please wait one moment ...