CIR Impact on the Plasma Environment of Comet 67P/CG
On 3 July 2015 the magnetometer RPC-MAG on the Rosetta spacecraft registered a dramatic increase in magnetic field strength to values above 270 nT. Together with enhancements in ion and electron density, as well as a reduction of high energy particles, this marks the strongest change in the plasma environment during the entire Rosetta mission.
Using solar wind prediction models as well as Earth based observations, it was possible to identify a Corotating Interaction Region as the trigger. Three regions of plasma features can be identified and related to the structure of CIRs. To further explore the interaction between the solar wind and the comet Hybrid simulations were performed with a simplified CIR structure. The reaction of the cometary plasma to an unusual solar wind event is then used to extrapolate general properties of the interaction region.