Simulating Planetary Surface Reactions with an Environmentally Controlled Experiment Chamber

Because of significant challenges posed by space exploration missions, experiments in simulation chambers could shed light on certain planetary processes of interest to support mission design and mission data interpretation, as well as for testing science payloads for missions. Here we present our planetary environment simulation system built at Washington University in St. Louis. The system includes a two-layer vacuum baking chamber for sample preparation and a vacuum reaction chamber (upgraded planetary environment and analysis chamber, PEACh) featuring controllable temperature, pressure, and gas composition. The upgraded PEACh can simulate water-rock interaction via a water injection port, and it can simulate space weathering by using an energetic electron impact (EEI) accessory. In addition, this vacuum reaction chamber is equipped with in-situ monitoring probes, including Raman spectroscopy and plasma spectroscopy, as well as a video camera. The whole system is mainly designed for simulating water-regolith interactions in the lunar polar regions, but it can also simulate other planetary environments, such as conditions at the martian surface. • We describe a facility for sample preparation and planetary surface simulation • The chamber has in-situ Raman and plasma probes to monitor reaction products. • System validation is demonstrated via hydration and dehydration of Mg-sulfates. • The facility investigates potential water-regolith reactions in lunar polar regions.