Four-fluid MHD Simulations of the Plasma and Neutral Gas Environment of Comet Churyumov-Gerasimenko Near Perihelio

Wednesday, 16 December 2015
Poster Hall (Moscone South)
Zhenguang Huang1, Gabor Toth1, Tamas I Gombosi2, Xianzhe Jia1, Martin Rubin3, Kenneth C Hansen1, Nicolas Fougere1, Andre Michel Bieler1, Yinsi Shou1, Kathrin Altwegg4, Michael R Combi1 and Valeriy Tenishev5, (1)University of Michigan Ann Arbor, Ann Arbor, MI, United States, (2)Univ of Michigan, Ann Arbor, MI, United States, (3)University of Bern, Bern, Switzerland, (4)Physikalisches Institut, University of Bern, Bern, Switzerland, (5)University of Michigan Ann Arbor, AOSS, Ann Arbor, MI, United States
The neutral and plasma environment is critical in understanding the interaction of comet Churyumov-Gerasimenko (CG), the target of the Rosetta mission, and the solar wind. To serve this need and support the Rosetta mission, we develop a 3-D four fluid model, which is based on BATS-R-US within the SWMF (Space Weather Modeling Framework) that solves the governing multi-fluid MHD equations and the Euler equations for the neutral gas fluid. These equations describe the behavior and interactions of the cometary heavy ions, the solar wind protons, the electrons, and the neutrals. This model incorporates different mass loading processes, including photo and electron impact ionization, charge exchange, dissociative ion-electron recombination, and collisional interactions between different fluids. We simulate the near nucleus plasma and neutral gas environment near perihelion with a realistic shape model of CG and compare our simulation results with Rosetta observations.