Presentation #213.07 in the session Mars Atmosphere (iPosters).
The impact of a solar flare on the atmosphere of Mars leads to substantial, short-lived changes in atmospheric density and composition. Simulations of the atmosphere’s flare-driven behavior offer increased global and temporal coverage to the detailed snapshots of atmospheric conditions which in-situ measurements from spacecraft at Mars provide during a solar flare event. To informedly utilize this broader global context and advance characterization of the atmosphere’s response to extreme solar conditions, it is necessary to assess a simulation’s reproduction of the flare-affected atmosphere through comparison with observations. Here, we present a comparison between observations and simulation outputs of the densities of main ion species in the upper atmosphere of Mars during the large, X8.2-class solar flare on 10 September 2017. For observations, we use MAVEN spacecraft mass spectrometer (NGIMS) measurements which captured in-situ ion densities approximately 90 minutes after peak ionizing flare irradiance reached Mars. For simulated conditions, we use simulation outputs from the global atmospheric circulation model MGITM under the initial atmospheric conditions and irradiance inputs of this flare event. While the simulated conditions of the neutral upper atmosphere in response to this flare have been demonstrated to reasonably capture the neutral densities of MAVEN observations (Fang et al. 2019), a corresponding comparison for ion species has not yet been made. Ion species behavior, as a significant factor in chemical processes and other interactions with the neutral atmosphere at Mars, may offer key insights into similarities and differences between the upper atmosphere’s observed and simulated behavior and processes under extreme solar conditions.