Numerical Simulation of Martian Ionospheric Irregularities

Martian ionospheric irregularities have been observed via Mars Atmosphere and Volatile EvolutioN (MAVEN) in situ measurements, but their generation mechanism is still unclear. In this work, we develop a two-dimensional model to investigate the formation of Martian irregularities. Both the simulation results and linear theory indicate that Martian ionospheric irregularities can be triggered by the Rayleigh-Taylor instability. Unlike at Earth, the irregularity at Mars strongly depends on the wavelength of perturbation. It is found that the large Hall conductivity (Hall current) at the Martian ionosphere is the cause of the complex irregularity structures, especially for long wavelength perturbations. Specifically, the Hall current leading to tilt transport of plasma disrupts the initial perturbation waves, and thus results in the formation of multiple small irregularity structures from non-linear process.