The interaction of Rhea with Saturn's magnetosphere
Abstract
Rhea, a 1500km-wide icy satellite of Saturn, orbits the planet at 8.7 Saturn radii. The Cassini spacecraft's single close approach to the moon to date occurred on November 26, 2005, approaching to within 500km of Rhea's surface. The LEMMS sensors of Cassini's MIMI instrument observed energetic (>20keV) electrons and ions in the moon's vicinity. As expected, a significant depletion was observed in low energy electrons downstream of the moon in the magnetospheric corotation flow. This missing population constituted particles that struck Rhea, forming a wake downstream. In addition to this relatively well-understood feature, the LEMMS data revealed a wide, relatively shallow electron flux depletion extending for several Rhea radii both inbound and outbound. Energetic ions also changed their characteristics within this broad region - a volume of space much larger than expected for a magnetospheric interaction with an inert body. We present our interpretation of this perplexing interaction region.
- Publication:
-
European Planetary Science Congress 2006
- Pub Date:
- 2006
- Bibcode:
- 2006epsc.conf..382J