Mercury being hit by a CME: A.I.K.E.F. Hybrid Plasma Simulation vs MESSENGER data
Abstract
Being the innermost planet in our solar system, Mercury is embedded in an intensive and highly varying solar wind.We use the hybrid code A.I.K.E.F. (Adaptive Ion Kinetic Electron Fluid) which treats ions kinetically and electrons as a mass-less fluid to simulate the vicinity of Mercury's magnetosphere.Mercury has an intrinsic dipole field which is aligned with the rotation axis and has an offset of 0.2 RM to the north along the z-axis, whereas RM = 2440 Km is the Hermean radius.Combining in-situ MESSENGER-data and the SUSANOO-Fluidcode, which simulates the solar wind up to 2 AU, Mercury got hit by a coronal mass ejection (CME) on Nov 23rd 2011.Over 30 min, the magnetic field of the solar wind ranges from 3-100 nT, the plasma density varies from 30-250 particles centimeter-3, for which the Bow-Shock position changes rapidly and passes the MESSENGER spacecraft 4 times.Based on the results of our simulations, the Dungey-cycle time-scale is of roughly 1 minute, resulting in a nearly adiabatic correlation between the CME upstream input variations and the magnetospheric response.Therefore, several simulations have to be combined for sufficient agreement with MESSENGER-data.In comparison to the southern cusp, the distribution of electric current over the northern cusp reveal a steady input into the near surface exosphere of 250 μ {A}/{m}2, which could induce polar lights.With further examination of those currents with the upcoming ESA and JAXA BepiColombo mission, we provide data sets useful for planning its orbit and prepare for analysis of future CMEs and possible polar lights.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMSM53B..03E
- Keywords:
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- 2740 Magnetospheric configuration and dynamics;
- MAGNETOSPHERIC PHYSICSDE: 2799 General or miscellaneous;
- MAGNETOSPHERIC PHYSICSDE: 5435 Ionospheres;
- PLANETARY SCIENCES: SOLID SURFACE PLANETSDE: 5443 Magnetospheres;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS