1:45 PM - 2:00 PM
[PEM10-25] Global Distribution of the Martian Nightside Ionosphere and Its Response to Space Weather and Crustal Magnetic Fields Based on MEX and MAVEN Observations
★Invited Papers
Keywords:Mars, Nightside Ionosphere, Crustal magnetic field, Solar wind
The ionosphere is one of the key regions that directly reflects the influence of space weather. While the dayside ionosphere of Mars has been studied in detail, the nightside ionosphere remains less explored due to observational limitations. However, the accumulation of long-term data from Mars Express (MEX) and MAVEN has enabled large-scale statistical analyses.
In this study, we utilize simultaneous observations from MEX and MAVEN spanning from October 2014 to November 2022 to investigate how the Martian nightside ionosphere responds to variations in the upstream solar wind and IMF. Specifically, we analyze nightside ionospheric echoes detected by MEX’s topside sounding to derive the global distribution of the peak electron density and detection frequency in the nightside ionosphere. Additionally, we employ MAVEN’s upstream solar wind observations to evaluate how upstream drivers influence nightside ionospheric variations. We also focus on the effects of crustal magnetic field strength on localized ionospheric variations. Furthermore, a comparison with Martian discrete aurora is conducted to assess the relationship between suprathermal electron precipitation and ionospheric variability.
This presentation will showcase these analyses, providing insights into how space weather and crustal magnetic fields influence the Martian nightside ionosphere.
In this study, we utilize simultaneous observations from MEX and MAVEN spanning from October 2014 to November 2022 to investigate how the Martian nightside ionosphere responds to variations in the upstream solar wind and IMF. Specifically, we analyze nightside ionospheric echoes detected by MEX’s topside sounding to derive the global distribution of the peak electron density and detection frequency in the nightside ionosphere. Additionally, we employ MAVEN’s upstream solar wind observations to evaluate how upstream drivers influence nightside ionospheric variations. We also focus on the effects of crustal magnetic field strength on localized ionospheric variations. Furthermore, a comparison with Martian discrete aurora is conducted to assess the relationship between suprathermal electron precipitation and ionospheric variability.
This presentation will showcase these analyses, providing insights into how space weather and crustal magnetic fields influence the Martian nightside ionosphere.