Dust-plasma interaction through magnetosphere-ionosphere coupling in Saturn's plasma disk

Shotaro Sakai, Shigeto Watanabe, Michiko W. Morooka, Madeleine K.G. Holmberg, Jan Erik Wahlund, Donald A. Gurnett, William S. Kurth

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)


The ion bulk speeds in the equatorial region of Saturn's inner magnetosphere, according to data from the Langmuir Probe (LP) on board the Cassini spacecraft, are about 60% of the ideal co-rotation speed; the ion speeds are between the co-rotation and Keplerian speeds (Holmberg et al.; Ion densities and velocities in the inner plasma torus of Saturn, Planetary and Space Science). These findings suggest that sub-micrometer negatively charged E ring dust contributes to the plasma dynamics in the plasma disk. We calculated the ion speeds by using a multi-species fluid model, taking into account dust interactions to investigate the effects of ion-dust coulomb collision, mass loading, as well as taking into account magnetosphere-ionosphere coupling to investigate the effect of the magnetospheric electric field. The results show that the ion speeds can be significantly reduced by the electric fields generated by the collisions between ions and dusts when the dust density is high and the thickness of dust distribution is large. We also show that the ion speeds from our model are consistent with the LP observations when the maximum density of dust is larger than ∼105 m-3.

Original languageEnglish
Pages (from-to)11-16
Number of pages6
JournalPlanetary and Space Science
Issue number1
Publication statusPublished - 2013 Jan


  • Co-rotation lag
  • Dust-plasma interaction
  • Dusty plasma
  • Magnetosphere-ionosphere coupling
  • Saturn


Dive into the research topics of 'Dust-plasma interaction through magnetosphere-ionosphere coupling in Saturn's plasma disk'. Together they form a unique fingerprint.

Cite this