Speaker: Yaxue Dong
Affiliation: LASP, University of Colorado Boulder
Date: Friday, October 9, 2026
Time: 3:30 PM
Zoom/Meeting Link: https://ucla.zoom.us/j/97178405473?pwd=WMx7ClxaSw38JatXhzPshjC5G0O1Um.1
Abstract
The NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission orbited Mars from 2014-2026 and has made extensive observations of the upper atmosphere and induced magnetosphere, providing more than a decade of invaluable data for investigating the Martian atmospheric loss. Using these observations, different ion escape channels have been identified, and the average global ion escape rate from present-day Mars, as well as its variability over a solar cycle, have been estimated. In addition, we have conducted quantitative analyses of the dependencies of ion escape rates on upstream solar radiation, solar wind, and IMF parameters, as well as Mars crustal magnetic field locations, to quantify the sensitivities and effects of these upstream and planetary drivers. The variations in different escaping ion populations are also examined to understand the physical mechanisms through which these drivers regulate ion escape from Mars. Together, these results identify the dominant drivers of the solar cycle variability of ion escape, provide constraints on the long-term atmospheric evolution of Mars, and offer broader insights into the processes governing atmospheric loss at unmagnetized and weakly magnetized planets.