Response of the Martian ionosphere to solar energetic particle events during solar cycle_24

The ionosphere of Mars is dynamic and continuously affected by a host of interconnected physical processes in the surrounding interplanetary environment. Despite significant advances in space and ground-based observations, the response of Martian ionosphere to solar transients has not been fully characterized. In this work, we use comprehensive observations from the Mars Atmosphere and Volatile Evolution (MAVEN), along with support from 1 AU spacecraft (ACE, Wind, GOES) to investigate the impact of interplanetary solar conditions (including Solar Energetic Particle events) on the Martian ionosphere. In particular, we aim at characterizing the structure and evolution of the Martian upper photochemical plasma layers to solar conditions. The response of the Martian ionosphere will be characterized at different altitudes and solar zenith angles (SZA) during the study period. The evolution of the dayside and nightside electrons and CO2 density profiles at different altitudes and solar illumination conditions will be examined based on MAVEN observations. The O/CO2 ratio will additionally be analysed at high altitudes, for markers into processes that affect atmospheric structure and composition. Finally, this project will provide an insight of the inhomogeneities (plasma clouds and holes) within the Martian atmosphere. To achieve these objectives, we will first identify a number of SEP events at Mars, using MAVEN multi-instrument observations and support from 1 AU platforms such as ACE and STEREO. This work is anticipated to improve the current dearth in understanding the Martian ionospheric response to solar transients, including plasma density variations during different stages of the SEP events. The PI has visited the Boston University (BU) and Southwest research Institute (SWRI) during summer 2018 and he established the collaboration on MAVEN data.