Liquid nitrogen removal of lunar regolith simulant from spacesuit simulants

Abstract

Lunar dust is a major concern for future missions to the Moon. The small size, abrasiveness, sharp morphology, toxicity, and pervasive nature of the dust can cause significant distress to both human health and equipment. Traditional spacesuit cleaning methods such as brushing and vacuuming have limited effectiveness and pose risks such as suit fabric abrasion and seal contamination. A novel mitigation method is to harness the properties of cryogenic liquids. As the liquid rapidly boils, insulated droplets form that lift and carry the dust away from the suit material, migrating toward the lowest point in an airlock for convenient collection. This publication discusses initial testing of the concept for removing lunar regolith simulant from spacesuit simulants with liquid nitrogen. A cryogen sprayer technology was adapted to investigate the effect of angle, application distance, and application time on the efficacy of dust removal. Methodology and uncertainty are presented to determine a removal percent by mass. Preliminary results show mass removal of simulated lunar dust from simulated spacesuit fabric to be greater than 90% for particles less than 10 microns. Estimated calculations are presented to demonstrate the suitability for using the concept to efficiently clean spacesuits and for the ancillary purpose of pressurizing an airlock.