Dr. Niki Xirogiannopoulou
Charles University, Prague, Czechia
October 5 , 2026 (Monday), 15:00
S4-917, Chien-Shiung Building

Abstract

In planetary magnetospheric systems, the turbulent region upstream of the bow shock, called the foreshock, consists of back-streaming particles and waves that interact with each other and create different transients that impact their surroundings and the downstream plasma. Foreshock transients play a key role in the solar wind-planetary coupling. In the terrestrial environment, these structures can propagate via different mechanisms, reach, impact the magnetopause – the dynamic boundary separating the solar wind from terrestrial magnetic field, and trigger magnetospheric disturbances. However, it is unclear to what extend similar processes operate in Mars, an unmagnetized planet with different dissipation mechanisms. By investigating these phenomena across two different planetary systems, we attempt to address the broader question of whether the foreshock processes are universal and how they are modulated (and modulating) under different magnetic field and plasma interactions. Using spacecraft data from the Mars Atmosphere and Volatile Evolution (MAVEN) mission, we conduct a statistical analysis on the characteristics and the occurrence rate of the different types of foreshock structures of Mars. Based on previous results obtained by Xirogiannopoulou et al. (2024, 2026), we compare the terrestrial and Martian structures in order to understand the effects of the different magnetic topology in their characteristics, evolution and impact.