第七届青年地学论坛

Based on Maven's NGISM neutral composition and Langmuir probe electron density and temperature data, we statistically analyzed the climatic variations of the Martian thermospheric neutral density and ionospheric electron density and temperature, and found that thermosphere density showed significant north-south hemisphere asymmetry. In winter and summer, it mainly comes from the north-south asymmetry of solar zenith angle.The observational data still show significant north-south asymmetry in equinox season. Under low solar radiation conditions, thermosphere density in the northern hemisphere is higher than that in the southern hemisphere, while under relatively high solar radiation conditions, thermosphere density in the southern hemisphere is higher than that in the northern hemisphere.In addition, the southern hemisphere increases non-linearly with the increase of solar radiation, while the northern hemisphere increases linearly.The electron density in the Martian ionosphere also shows significant north-south asymmetry in seasons. The electron density in the southern hemisphere is higher than that in the northern, and the electron temperature in the southern hemisphere is lower than that in the northern. These ionospheric and thermospheric asymmetries are likely to be related to the significant north-south terrain difference or the north-south asymmetry of the remaining magnetic field on Mars. Further observations and simulation analysis are needed to confirm the north-south asymmetry of the upper atmosphere of Mars.
 

Martian ionosphere,solar flare