Global Current System of Martian Induced Magnetosphere: a Hybrid View

Recent spacecraft observations have revealed the averaged global morphology of the magnetospheric current system of Mars. This current system is generated by the induction of the interplanetary magnetic field and the motional electric field of the solar wind. It couples the ionosphere below and the solar wind above and determines the distribution of the energy inputs from the fast-moving solar wind to the planetary atmospheric ions.

We use Amitis, a GPU-based hybrid (particle ions and fluid electrons) numerical model to study the current system. Under the typical space environment condition, we successfully reproduce the morphology of the observed current system, including the bow shock current, the induced magnetospheric boundary current, and the ionospheric current.

With the full information provided by the model, we can calculate the inner product of the electric field intensity and the current density for any location in the simulation domain. Furthermore, we can separate the currents due to solar wind and planetary ions, and separate the electric field terms caused by different mechanisms, thereby clarifying the contribution of different mechanisms to the ion escape in the solar wind interaction with Mars.