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An important milestone in the ongoing effort by NASA to develop and refine closed-loop water recycling systems for human space flight was reached during the summer of 1996 with the successful completion of Phase II of the Lunar Mars Life Support Testing Program at Johnson Space Center. Part of Phase II involved testing a water-recycling system in a closed test chamber continuously occupied by four human subjects for thirty days. The Phase II crew began the test with a supply of water that had been processed and certified for human use. As the test progressed, humidity condensate, urine, and wastewater from personal hygiene and housekeeping activities were reclaimed and reused several times. Samples were collected from various points in the reclamation process during the thirty day test. The data verified the water-processing hardware can reliably remove wastewater contaminants and produce reclaimed water that meets NASA standards for hygiene- and potable-quality water.

To satisfy a requirement to supply water to Mir station, a process for treating iodinated water on the Shuttle was developed and implemented. The treatment system consists of packed columns for removing iodine and a syringe-based injection system for adding ionic silver, the biocide used in Mir water. Technical and potable grade water is produced and transferred in batches using collapsible 44-liter contingency water containers (CWCs). Silver is added to the water via injection of a solution from preloaded syringes. Minerals are also added to water destined for drinking. During the previous four Shuttle-Mir docking missions a total of 2781 liters (735 gallons) of water produced by the Shuttle fuel cells was processed using this method and transferred to Mir. To verify the quality of the processed water, samples were collected during flight and returned for chemical analysis.

The first two phases of the Lunar-Mars Life Support Test Project [LMLSTP] involved housing human volunteers in closed chambers that mimic future extraterrestrial life support systems. The Phase I test involved one person living for 15 days in a chamber with wheat as the primary means of air revitalization. The Phase II test involved 4 people living for 30 days in a chamber with physical/chemical air revitalization and waste water recycling. The consequences of closure on microbial ecology and the influence that microbes had on these closed environmental life support systems were determined during both tests. The air, water, and surfaces of each chamber were sampled for microbial content before, during, and after each test. The numbers of microbes on the Phase I habitation chamber surfaces increased with length of occupation.

An 84 day wheat crop was grown in the Variable Pressure Growth Chamber (VPGC) at Johnson Space Center (JSC). The VPGC is an atmospherically closed, controlled environment facility used to evaluate the use of higher plants as part of a regenerative life support system. The chamber has 10.6 m2 of growing area consisting of 480 pots of calcined clay support media. The chamber is lit by very high output, cool white fluorescent bulbs. Five wheat seeds were planted per pot giving a seeding density of 227 seeds·m-2. Pots were irrigated with a modified half strength Hoagland's nutrient solution three or six times per day depending on the crop age. At the plant canopy, the average temperature during the test was 22 ° C, relative humidity was maintained at 69%, CO2 concentration was 1000 ppm, photoperiod was continuous light, and the light intensity averaged 350 μmol·m-2·s-1.

ANITA (Analysing Interferometer for Ambient Air) is a flight experiment precursor for a permanent continuous air quality monitoring system on the ISS (International Space Station). For the safety of the crew, ANITA can detect and quantify quasi-online and simultaneously 33 gas compounds in the air with ppm or sub-ppm detection limits. The autonomous measurement system is based on FTIR (Fourier Transform Infra-Red spectroscopy). The system represents a versatile air quality monitor, allowing for the first time the detection and monitoring of trace gas dynamics, with high time resolution, in a spacecraft atmosphere. ANITA operated on the ISS from September 2007 to August 2008. This paper summarises the results of ANITA's air analyses and compares results to other measurements acquired on ISS during the operational period.

During Lunar missions, NASA's new Orion Crew Exploration Vehicle (CEV) may benefit from mass savings and increased reliability by the use of a passive, capillary-driven Static Phase Separator (SPS) for urine collection, containment, and disposal in place of a rotary-fan separator and wastewater storage tank. The design of a capillary separator addresses unique challenges for microgravity fluid management for liquids with a wide range of possible contact angles and high air-to-liquid flow ratio. This paper presents the iterative process leading to a successful test in a reduced gravity aircraft of the SPS concept. Using appropriately scaled test conditions, the resulting prototype allows for a range of wetting properties with complete separation of liquid from gas.

Ground-based laboratory and closed-chamber human tests have demonstrated the ability of microbial-based biological processors to effectively remove carbon and nitrogen species from regenerable life support wastewater streams. Application of this technology to crewed spacecraft requires the development of gravity-independent bioprocessors due to a lack of buoyancy-driven convection and sedimentation in microgravity. This paper reports on the development and testing of membranebased biological reactors and addresses the processing of planetary and International Space Station (ISS) waste streams. The membranes provide phase separation between the wastewater and metabolically required oxygen, accommodate diffusion-driven oxygen transport, and provide surface area for microbial biofilm attachment. Testing of prototype membrane bioprocessors has been completed.

In preparation for future planetary exploration, NASA-Johnson Space Center has developed a critical path plan for food and nutrition research needs. The plan highlights the risk factors pertaining to food and nutrition associated with exposure to the space flight environment as well as the possible consequences if no corrective measures are implemented. Included in the plan are the initiating events such as microgravity, remote environment and mission duration, which obviously impact the risk factors. The plan includes points of intervention where mitigating factors can be implemented to avoid outcomes such as malnutrition and unsafe foods. Physiological changes induced by lack of gravity, as well as increased exposure to radiation, may alter nutrient bio-availability and/or nutrient requirements. An inadequate food system, whether due to technical limitations or nutritional shortcomings, can result in serious consequences.

To support manned lunar and Martian exploration, NASA/JSC and LESC are conducting an extensive evaluation of air revitalization subsystems. The major operations under study include regenerative CO2 removal and reduction; O2 and N2 production, storage, and distribution; humidity and temperature control; and trace contaminant control. This paper describes the ongoing analysis of air revitalization subsystems, including ASPEN PLUS™ modeling and breadboard test stand operation. A comprehensive analysis program based on a generalized block flow model is currently being developed to facilitate the evaluation of various processes and their interactions. Future plans for the development of this simulation will be discussed. ASPEN PLUS™ has been used to model a variety of the subsystems described above; application of this package in modeling CO2 removal and reduction will be discussed.

Yardney Technical Products is developing a high energy density Li-ion cell tailored for NASA's Extravehicular Mobility Unit battery. The goal of the program is to develop a Li-ion technology which offers long storage and cycle life in a system which provides energy density and exercise performance comparable to the current 6.7kg Zn-AgO battery. The Zinc-Silver Oxide cells which are most commonly used in this application provide 400 Wh/l with a 32 cycle life at 26.6Ah and 1.55V with a rated wet life of 425 days. To improve the energy density of the Li-ion cells we have focused on improving the energy density of its components. In addition to using thin metal foil current collectors, the energy density of the cathode material was improved by utilizing a high capacity Co doped nickel oxide material. Further efforts have focused on developing a more energy dense carbonaceous anode material. The results of this effort are reviewed.