Mineral Weathering Experiments for Terrestrial Planetary Analogs in a Continuous‐Flow Reactor

Understanding the groundwater environments for ancient Mars and other terrestrial bodies is of great interest for evaluating their habitability. Here, we experimentally tested simulated aqueous alterations of two Mars simulants (variants of MGS‐1) using a continuous‐flow packed bed reactor, reacting with three ionic simulated groundwater analog solutions containing MgSO 4 , FeSO 4 , or LiCl to explore the impact of the aqueous alteration on the minerals. The minerals from these experiments were analyzed via Mars mission–relevant and field‐relevant techniques (LIBS, Vis‐NIR, and XRF). We demonstrated that the liquid collected from the column outflow and the solid samples were impacted by the alteration. With the MGS‐1 standard, we found that sulfate mineral dissolution occurred in all tested experimental conditions; however, in cases with FeSO 4 and MgSO 4 , dissolution of gypsum might have been disfavored. In addition, when the simulants were exposed to LiCl solution, Li was easily detectable by LIBS analysis of the residual mineral material. We then contextualize how these results could inform observations by ongoing Mars missions.