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Lunar dust exposures occurred during the Apollo missions while the crew was in the lunar module on the moon's surface and especially when micro-gravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes, and in some cases, respiratory symptoms were elicited. NASA's current vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust in the habitat need to be assessed. NASA is performing this assessment with a series of in vitro and in vivo tests with authentic lunar dust. Our approach is to “calibrate” the intrinsic toxicity of lunar dust by comparison to a relatively low toxicity dust (TiO2) and a highly toxic dust (quartz) using intrapharyngeal instillation of the dusts to mice. A battery of indices of toxicity is assessed at various time points after the instillations.

Maintaining a healthy atmosphere in closed life support systems is essential for the crew well being and the success of manned space missions. During the SBIR Phase I effort, Lynntech, Inc., developed a bench scale trace contaminant control (TCC) system utilizing a photocatalytic filter. Testing successfully demonstrated the technology feasibility for eliminating airborne chemicals and microorganisms. During the SBIR Phase II project, a scaled-up, fully operational breadboard system is being developed and tested. Testing gases include chemicals significantly present in the International Space Station cabin air and that are drivers in the design of trace contaminant control systems. The use of Lynntech’s air cleaner allows for a system that is cost-effective and functional with a superior removal of gas pollutants and bio-aerosols from contaminated air streams beyond the capabilities of traditional photocatalysis. It also overcomes limitations of current TCC systems.

Fiber-reinforced Aerogel composite insulations provide superior thermal insulation protection in both the low-earth orbit (LEO) and near-earth neighborhood planetary environments. The flexible nature and thermal properties of these materials make them the best insulation candidates for advanced space suit application. This paper reviews the properties of various Aerogel composite materials developed for NASA by Aspen Systems, Inc. Previous studies showed that the Aerogel materials retained acceptable thermal performance after some amount of mechanical cycling. The goal of the current work is to reach a complete understanding of the mechanical properties of these materials in the domain of space suit application. Hence, a good knowledge of the durability of the aerogel composites is needed. This paper presents the extensive testing program needed to determine the life of these insulations for advanced space suit application.

Approximately 50% of the water consumed by International Space Station crewmembers is water recovered from cabin humidity condensate. Condensing heat exchangers in the Russian Service Module (SM) and the United States On-Orbit Segment (USOS) are used to control cabin humidity levels. In the SM, humidity condensate flows directly from the heat exchanger to a water recovery system. In the USOS, a metal bellows tank located in the US Laboratory Module (LAB) collects and stores condensate, which is periodically off-loaded in about 20-liter batches to Contingency Water Containers (CWCs). The CWCs can then be transferred to the SM and connected to a Condensate Feed Unit that pumps the condensate from the CWCs into the water recovery system for processing. Samples of the condensate in the tank are collected during the off-loads and returned to Earth for analyses.

Humidity condensate collected and processed in-flight is an important component of a space station drinking water supply. Water recovery systems in general are designed to handle finite concentrations of specific chemical components. Previous analyses of condensate derived from spacecraft and ground sources showed considerable variation in composition. Consequently, an investigation was conducted to collect condensate on the Shuttle while the vehicle was docked to Mir, and return the condensate to Earth for testing. This scenario emulates an early ISS configuration during a Shuttle docking, because the atmospheres intermix during docking and the condensate composition should reflect that. During the STS-89 and STS-91 flights, a total volume of 50 liters of condensate was collected and returned. Inorganic and organic chemical analyses were performed on aliquots of the fluid.

Currently used instruments for the analysis of total inorganic carbon (TIC) and total organic carbon (TOC) in water and wastewater samples require the use of hazardous chemicals which is not acceptable in their application for long-term space missions. A new design concept of the “reagentless” carbon analyzer (RCA) for determination of both TIC and TOC for water quality monitoring in space is proposed and tested. The concept is based on generating all the chemicals needed for the TIC and TOC analysis within the instrument, and avoiding the need for storing a supply of chemicals. The chemicals are either generated or recirculated in the instrument, or an alternative approach for their use is developed, such as using photocatalytic oxidation instead of oxidizing chemicals for TOC analysis. The fully developed miniaturized instrument will incorporate microfluidic based design principles.