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Spacecraft radiators reject heat to their surroundings. Radiators can be deployable or mounted on the body of the spacecraft. NASA's Crew Exploration Vehicle is to use body mounted radiators. Coatings play an important role in heat rejection. The coatings provide the radiator surface with the desired optical properties of low solar absorptance and high infrared emittance. These specialized surfaces are applied to the radiator panel in a number of ways, including conventional spraying, plasma spraying, or as an appliqué. Not specifically designed for a weathering environment, little is known about the durability of conventional paints, coatings, and appliqués upon exposure to weathering and subsequent exposure to solar wind and ultraviolet radiation exposure. In addition to maintaining their desired optical properties, the coatings must also continue to adhere to the underlying radiator panel.

For NASA's Constellation Program, an Intravehicular Activity (IVA) and Extravehicular Activity (EVA) Life Support Umbilical System (LSUS) will be required to provide environmental protection to the suited crew during Crew Exploration Vehicle (CEV) cabin contamination or depressurization and contingency EVAs. The LSUS will provide the crewmember with ventilation, cooling, power, communication, and data, and will also serve as a crew safety restraint during contingency EVAs. The LSUS will interface with the Vehicle Interface Assembly (VIA) in the CEV and the Suit Connector on the suit. This paper describes the effort performed to develop concept designs for IVA and EVA umbilicals, universal multiple connectors, handling aids and stowage systems, and VIAs that meet NASA's mission needs while adhering to the important guiding principles of simplicity, reliability, and operability.

As part of preparing for the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) worked on developing the requirements to manage the fire risk. The new CEV poses unique challenges to current fire protection systems. The size and configuration of the vehicle resembles the Apollo capsule instead of the current Space Shuttle or the International Space Station. The smaller free air volume and fully cold plated avionic bays of the CEV requires a different approach in fire protection than the ones currently utilized. The fire protection approach discussed in this paper incorporates historical lessons learned and fire detection and suppression system design philosophy spanning from Apollo to the International Space Station.

Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center (JSC) serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat by up to eight persons. A variety of gas analyzers and dew point sensors are used to monitor the chamber atmosphere and the process flow upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space.

Similar to finding a home on Earth, location is important when selecting where to set up an exploration outpost. Essential considerations for comparing potential lunar outpost locations include: (1) areas nearby that would be useful for In-Situ Resource Utilization (ISRU) oxygen extraction from regolith for crew breathing oxygen as well as other potential uses; (2) proximity to a suitable landing site; (3) availability of sunlight; (4) capability for line-of-sight communications with Earth; (5) proximity to permanently-shadowed areas for potential in-situ water ice; and (6) scientific interest. The Mons Malapert1 (Malapert Mountain) area (85.5°S, 0°E) has been compared to these criteria, and appears to be a suitable location for a lunar outpost.

A reliable nutrient delivery system is essential for long-term cultivation of plants in space. At the Kennedy Space Center, a series of ground-based tests are being conducted to compare candidate plant nutrient delivery systems for space. To date, our major focus has concentrated on the Porous Tube Plant Nutrient Delivery System, the ASTROCULTURE™ System, and a zeoponic plant growth substrate. The merits of each system are based upon the performance of wheat supported over complete growth cycles. To varying degrees, each system supported wheat biomass production and showed distinct patterns for plant nutrient uptake and water use.

Scientists and engineers at NASA are currently developing flight instruments which will demonstrate oxygen production on the Moon and Mars. REGA will extract oxygen from the lunar regolith, measure implanted solar wind and indigenous gases, and monitor the lunar atmosphere. MIP will demonstrate oxygen production on Mars, along with key supporting technologies including filtration, atmospheric acquisition and compression, thermal management, solar cell performance, and dust removal.

In-situ production of oxygen and methane for utilization as a return propellant from Mars for both sample-return and manned missions is currently being developed by NASA in cooperation with major aerospace companies. Various technologies are being evaluated using computer modeling and analysis at the system level. An integrated system that processes the carbon dioxide in the Mars atmosphere to produce liquid propellants has been analyzed. The system is based on the Sabatier reaction that utilizes carbon dioxide and hydrogen to produce methane and water. The water is then electrolyzed to produce hydrogen and oxygen. While the hydrogen is recycled, the propellant gases are liquefied and stored for later use. The process model considers the surface conditions on Mars (temperature, pressure, composition), energy usage, and thermal integration effects on the overall system weight and size. Current mission scenarios require a system that will produce 0.7 kg of propellant a day for 500 days.

We present the development of a semiconductor diode laser spectral absorption based gas species sensor for oxygen concentration measurements, intended for life support system monitoring and control applications. Employing a novel self-compensating, noise cancellation detection approach, we experimentally demonstrate better than 1% accuracy, linearity, and stability for monitoring breathing air conditions with 0.2 second response time. We also discuss applications of this approach to CO2 sensing.

Space environmental control systems must control cabin temperature and humidity. This can be achieved by transferring the heat load to a circulating coolant, condensing the humidity, and separating the condensate from the air stream. In addition, environmental control systems may be required to remove particulate matter from the air stream. An assembly comprised of a filter, a condensing heat exchanger, a thermal control valve, and a liquid carryover sensor, is used to achieve all these requirements. A condensing heat exchanger and filter assembly (CHXFA) is being developed and manufactured by SECAN/AlliedSignal under a contract from Dornier Daimler-Benz as part of a European Space Agency program. The CHXFA is part of the environmental control system of the Columbus Orbital Facility (COF), the European laboratory module of the International Space Station (ISS).

Advanced life support flight experiments have been conceptualized for the International Space Station (ISS). Two of the experiments, a high pressure oxygen generator and a carbon dioxide reduction subsystem, offer high payback potential to the ISS program. This paper documents the cost-benefit analyses for these two experiments.

A two year test program has been initiated to evaluate the effects of extended duration operation on a solid polymer electrolyte Oxygen Generator Assembly (OGA); in particular the cell stack and membrane phase separators. As part of this test program, the OGA was integrated into the Marshall Space Flight Center (MSFC) Water Recovery Test (WRT) Stage 10, a six month test, to use reclaimed water directly from the water processor product water storage tanks. This paper will document results encountered and evaluated thus far in the life testing program.

Absorption cooling using a lithium chloride/water heat pump can enable lightweight and effective thermal control for Extravehicular Activity (EVA) suits without venting water to the environment. The key components in the system are an absorber/radiator that rejects heat to space and a flexible evaporation cooling garment that absorbs heat from the crew member, This paper describes progress in the design, development, and testing of the absorber/radiator and evaporation cooling garment. New design concepts and fabrication approaches will significantly reduce the mass of the absorber/radiator. We have also identified materials and demonstrated fabrication approaches for production of a flexible evaporation cooling garment, Data from tests of the system's modular components have validated the design models and allowed predictions of the size and weight of a complete system.

The International Space Station (ISS) program is nearing an assembly complete configuration with the addition of the final resource node module in early 2010. The Node 3 module will provide critical functionality in support of permanent long duration crews aboard ISS. The new module will permanently house the regenerative Environment Control and Life Support Systems (ECLSS) and will also provide important habitability functions such as waste management and exercise facilities. The ISS program has selected the Port side of the Node 1 “Unity” module as the permanent location for Node 3 which will necessitate architecture changes to provide the required interfaces. The USOS ECLSS fluid and ventilation systems, Internal Thermal Control Systems, and Avionics Systems require significant modifications in order to support Node 3 interfaces at the Node 1 Port location since it was not initially designed for that configuration.

A system of amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and is baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of the technology, which was performed in a representative environment with simulated human metabolic loads. The next step in developmental testing at JSC was to use real human loads in the spring of 2008.

Long duration human space missions, as planned in the Vision for Space Exploration, will not be possible without applying unprecedented levels of automation to support the human endeavors. The automated and robotic systems must carry the load of routine “housekeeping” for the new generation of explorers, as well as assist their exploration science and engineering work with new precision. Fortunately, the state of automated and robotic systems is sophisticated and sturdy enough to do this work — but the systems themselves have never been human-rated as all other NASA physical systems used in human space flight have. Our intent in this paper is to provide perspective on requirements and architecture for the interfaces and interactions between human beings and the astonishing array of automated systems; and the approach we believe necessary to create human-rated systems and implement them in the space program.

The International Space Station (ISS) Active Thermal Control System (ATCS) (Ref. 1,2) has changed over the past several years to address problems and to improve its assembly and operation on-orbit. This paper captures the ways in which the Internal (I) ATCS and External (E) ATCS have changed design characteristics and operations both for the system currently operating on-orbit and the new elements of the system that are about to be added and/or activated. The rationale for changes in ATCS design, assembly and operation will provide insights into the lessons learned during ATCS development. The state of the assembly of the integrated ATCS will be presented to provide a status of the build-up of the system. The capabilities of the on-orbit system will be presented with a summary of the elements of the ISS ATCS that are functional on-orbit plus the plans for launch of remaining parts of the integrated ISS ATCS.

Biological water processors are currently being developed for application in microgravity environments. Work has been performed to develop a single-phase, gravity independent anoxic denitrification reactor for organic carbon removal [1]. As a follow on to this work it was necessary to develop a gravity independent nitrification reactor in order to provide sufficient nitrite and nitrate to the organic carbon oxidation reactor for the complete removal of organic carbon. One approach for providing the significant amounts of dissolved oxygen required for nitrification is to require the biological reactor design to process two-phase gas and liquid in micro-gravity. This paper addresses the design and test results overview for development of a tubular, two-phase, gravity independent nitrification biological water processor.

The Equivalent System Mass (ESM) metric developed by NASA describes and compares individual system impact on a closed system in terms of a single parameter, mass. The food system of a Mars mission may encompass a large percentage of total mission ESM, and decreasing this ESM would be beneficial. Yeast breads were made using three methods (hand & oven, bread machine, mixer with dough hook attachment & oven). Flat breads were made using four methods (hand & oven, hand & griddle, mixer with dough hook attachment & oven, mixer with dough hook attachment & griddle). Two formulations were used for each bread system (scratch ingredients, commercial mix). ESM was calculated for each of these scenarios. The objective of this study was to compare the ESM of yeast and flat bread production for a Martian surface outpost. Method (equipment) for both types of bread production was demonstrated to be the most significant influence of ESM when one equipment use was assumed.

The purification of waste water is a critical element of any long-duration space mission. The Vapor Phase Catalytic Ammonia Removal (VPCAR) system offers the promise of a technology requiring low quantities of expendable material that is suitable for exploration missions. NASA has funded an effort to produce an engineering development unit specifically targeted for integration into the NASA Johnson Space Center's Integrated Human Exploration Mission Simulation Facility (INTEGRITY) formally known in part as the Bioregenerative Planetary Life Support Test Complex (Bio-Plex) and the Advanced Water Recovery System Development Facility. The system includes a Wiped-Film Rotating-Disk (WFRD) evaporator redesigned with micro-gravity operation enhancements, which evaporates wastewater and produces water vapor with only volatile components as contaminants. Volatile contaminants, including organics and ammonia, are oxidized in a catalytic reactor while they are in the vapor phase.