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The operation of a crop growth system in micro-gravity is an important part of the National Aeronautics and Space Administration's Closed Ecological Life Support System development program. Maintaining densely arrayed plants in a closed environment imposed to induce high growth rates must be expected to result in substantial levels of water transpiration rate. Since the environmental air is recirculated, the transpiration water must be removed. In an operating CELSS, it is expected that this water will provide potable water for use of the crew. There is already considerable knowledge about water removal from crew environmental air during orbital and transfer activities, and the difference between the conditions of the described requirement and the conditions for which experience has been gained is the quantities involved and the reliability implications due to the required periods of operation.

The least expensive life support for brief human missions is direct supply of all water and oxygen from Earth without any recycling. The currently most advanced human life support system was designed for the International Space Station (ISS) and will use physicochemical systems to recycle water and oxygen. This paper compares physicochemical to direct supply air and water life support systems using Equivalent Mass (EM). EM breakeven dates and EM ratios show that physicochemical systems are more cost effective for longer mission durations.

Waste management is a vital function of spacecraft life support systems as it is necessary to meet crew health and safety and quality of life requirements. Depending on the specific mission requirements, waste management operations can include waste collection, segregation, containment, processing, storage and disposal. For the Crew Exploration Vehicle (CEV), addressing volume and mass constraints is paramount. Reducing the volume of trash prior to storage is a viable means to recover habitable volume, and is therefore a particularly desirable waste management function to implement in the CEV, and potentially in other spacecraft as well. Research is currently being performed at NASA Ames Research Center to develop waste compaction systems that can provide both volume and mass savings for the CEV and other missions.

Waste management is a critical component of life support systems for manned space exploration. Human occupied spacecraft and extraterrestrial habitats must be able to effectively manage the waste generated throughout the entire mission duration. The requirements for waste systems may vary according to specific mission scenarios but all waste management operations must allow for the effective collection, containment, processing, and storage of unwanted materials. NASA's Crew Exploration Vehicle usually referred to as the CEV, will have limited volume for equipment and crew. Technologies that reduce waste storage volume free up valuable space for other equipment. Waste storage volume is a major driver for the Orion waste compactor design. Current efforts at NASA Ames Research Center involve the development of two different prototype compactors designed to minimize trash storage space.

We present a device for collecting and storing feces in microgravity that is user-friendly yet suitable for spacecraft in which cabin volume and mass are constrained. On Apollo missions, the commode function was served using disposable plastic bags, which proved time-consuming and caused odor problems. On Skylab, the space shuttle, and the International Space Station, toilets have used airflow beneath a seat to control odors and collect feces. We propose to incorporate airflow into a system of self-compacting, self-drying collection and stowage bags, providing the benefits of previous commodes while minimizing mass and volume. Each collection bag consists of an inner layer of hydrophobic membrane that is permeable to air but not liquid or solid waste, an outer layer of impermeable plastic, and a collapsible spacer separating the inner and outer layers. Filled bags are connected to space vacuum, compacting and drying their contents.

This paper considers the design of a life support system for transit to Mars and return to Earth. Because of the extremely high cost of launching mass to Mars, the Mars transit life support system must minimize the amount of oxygen, water, and food transported. The three basic ways to provide life support are to directly supply all oxygen and water, or to recycle them using physicochemical equipment, or to produce them incidentally while growing food using crop plants. Comparing the costs of these three approaches shows that physicochemical recycling of oxygen and water is least costly for a Mars transit mission. The long mission duration also requires that the Mars transit life support system have high reliability and maintainability. Mars transit life support cannot make use of planetary resources or gravity. It should be tested in space on the International Space Station (ISS).

Some selected segments of the ascent and the on-orbit data from the Space Shuttle flight, STS114, as well as some selected laboratory test article data have been analyzed using wavelets, power spectrum and autocorrelation function. Additionally, a simple approximate noise test was performed on these data segments to confirm the presence or absence of white noise behavior in the data. This study was initially directed at characterizing the on-orbit background against which a signature due to an impact during on-orbit operation could be identified. The laboratory data analyzed here mimic low velocity impact that the Orbiter may be subjected to during the very initial stages of ascent.

Terraforming of Mars is the long-term goal of colonization of Mars. However, this process is likely to be a very slow process and conservative estimates involving a synergetic, technocentric approach suggest that it may take around 10,000 years before the planet can be parallel to that of Earth and where humans can live in open systems (Fogg, 1995). Hence, for the foreseeable future, any missions will require habitation within small confined habitats with high biomass to atmospheric mass ratios, thereby requiring that all wastes be recycled. Processing of the wastes will ensure predictability and reliability of the ecosystem and reduce resupply logistics. Solid wastes, though smaller in volume and mass than the liquid wastes, contain more than 90% of the essential elements required by humans and plants.

A habitat for housing up to 32 Tenebrionid, black body beetles (Trigonoscelis gigas Reitter) has been developed at Ames Research Center for conducting studies to evaluate the effects of long duration spaceflight upon insect circadian timing systems. This habitat, identified as the Beetle Kit, provides an automatically controlled lighting system and activity and temperature recording devices, as well as individual beetle enclosures. Each of the 32 enclosures in a Beetle Kit allows for ad lib movement of the beetle as well as ventilation of the beetle enclosure via an externally operated hand pump. Two Beetle Kits were launched on STS-84 (Shuttle-Mir Mission-06) on May 15, 1997 and were transferred to the Priroda module of the Russian Mir space station on May 18 as part of the NASA/Mir Phase 1 Science Program. Following the Progress collision with Spektr on June 25, the Kits were transferred to the Kristall module. The beetles will remain on Mir for approximately 135 days.

This study examines the current state of the art in rodent habitats as well as the next generation of rodent habitats currently under development at NASAs Ames Research Center. Space Shuttle missions are currently limited in duration to just over two weeks. In contrast to this, future life science missions aboard the Space Station may last months or even years. This will make resource conservation and utilization critical issues in the development of rodent habitats for extended microgravity missions. Emphasis is placed on defining rodent requirements for extended space flights of up to 90 days, and on improving habitability and extending the useful performance life of rodent habitats.

An innovative design that meets both Shuttle and Space Station requirements for a user-friendly, volume-efficient, portable glovebox system has been developed at Ames Research Center (ARC). The Standard Interface Glovebox (SIGB) has been designed as a two Middeck locker-sized system that mounts in a Middeck Rack Structure (MRS) or in any rack using the Standard Interface Rack (SIR) rail spacing. The MRS provides structural support for the SIGB during all aspects of the mission and is an interface consistent with NASA's desire for commonality of mechanical interfaces, allowing the SIGB to be flown on essentially any manned space platform. The SIGB provides an enclosed work volume which operates at negative pressure relative to ambient, as well as excellent lighting and ample work volume for anticipated life sciences-related experiment operations inflight.

For the last two years, the University of Utah and Reaction Engineering International, in cooperation with NASA Ames Research Center (ARC), have been developing a waste incineration system for regenerative life support systems. The system is designed to burn inedible plant biomass and human waste. The goal is to obtain an exhaust gas clean enough to recycle to either the plant or human habitats. The incineration system, a fluidized bed reactor, has been designed for a 4-person mission. This paper will detail the design of the units. In addition, results will be presented from testing at the University of Utah. Presently, the unit has been shipped to Ames Research Center for more tests prior to delivery to Johnson Space Center for testing in a 90-day, 4-person test.

PGBA, a plant growth facility developed for commercial space biotechnology research, successfully grew a total of 50 plants (6 species) during 10 days aboard the Space Shuttle Endeavor (STS-77), and has reflown aboard the Space Shuttle Columbia (STS-83 for 4 days and STS-94 for 16 days) with 55 plants and 10 species. The PGBA life support system provides atmospheric, thermal, and humidity control as well as lighting and nutrient supply in a 33 liter microgravity plant growth chamber. The atmosphere treatment system removes ethylene and other hydrocarbons, actively controls CO2 replenishment, and provides passive O2 control. Temperature and humidity are actively controlled.

The reproductive ontogeny of ‘Super-Dwarf’ wheat grown on the space station Mir is chronicled from the vegetative phase through flower' development. Changes in the apical meristem associated with transition from the vegetative plhase to floral initiation and development of the reproductive spike were all typical of ‘Super Dwarf’ wheat up to the point of anthesis. Filament elongation, which characteristically occurs just prior to anthesis (during floral development stage 4) and moves the anthers through the stigmatic branches thus facilitating pollination, did not occur in the flowers of spikes grown on Mir. While pollen did form in the anthers, no evidence of pollination or fertilization was observed. Analysis of pollen idlentified abnormalities; the presence of only one nucleus in the pollen as opposed to the normal trinucleate condition is likely an important factor in the sterility observed in wheat grown on Mir.

This paper compares four potential water treatment systems in the context of their applicability to a Mars transit vehicle mission. The systems selected for evaluation are the International Space Station system, a JSC bioreactor-based system, the vapor phase catalytic ammonia removal system, and the direct osmotic concentration system. All systems are evaluated on the basis of their applicability for use in the context of the Mars Reference Mission. Each system is evaluated on the basis of mass equivalency. The results of this analysis indicate that there is effectively no difference between the International Space Station system and the JSC bioreactor configurations. However, the vapor phase catalytic ammonia removal and the direct osmotic concentration systems offer a significantly lower mass equivalency (approximately 1/7 the ISS or bioreactor systems).

Ames Research Center's Life Sciences Division was responsible for managing the development of fundamental biology flight experiments during the Phase 1 NASA/Mir Science Program. Beginning with astronaut Norm Thagard's historic March, 1995 Soyuz rendezvous with the Mir station and continuing through Andy Thomas' successful return from Mir onboard STS-91 in June, 1998, the NASA/Mir Science Program has provided scientists with unparalleled long duration research opportunities. In addition, the Phase 1 program has yielded many valuable lessons to program and project management personnel who are managing the development of future International Space Station payload elements. This paper summarizes several of the key space station challenges faced and associated lessons learned by the Ames Research Center Fundamental Biology Research Project.

The space environment presents many challenges to the operation and functioning of life support systems. These challenges include reduced gravity, near vacuum ambient, extreme temperatures, and radiation. Proper testing and modeling of system components to account for these factors will be important for their verification. This paper describes the modeling and design of a reduced gravity test rig for waste management studies. The first investigation planned relate to the functioning of components of the Flexible Membrane Commode (FMC) currently under development at NASA Ames Research Center. The planned reduced gravity tests will be carried out in NASA's C'9 aircraft which provides approximately 25 seconds of reduced gravity per parabolic trajectory. The filling of the commode bag under the influence of a directed air flow will be studied. Simulated waste will be injected and cabin air will be used for directing the waste into the bag.

Dynamic simulation of the Lunar Outpost habitat life support was undertaken to investigate the impact of Extravehicular Activity (EVA). The preparatory static analysis and some supporting data are reported in another paper. (Jones, 2008-01-2184) Dynamic simulation is useful in understanding systems interactions, buffer needs, control approaches, and responses to failures and changes. A simulation of the Lunar outpost habitat life support was developed in MATLAB/Simulink™. The simulation is modular and reconfigurable, and the components are reusable to model other physicochemical (P/C) based recycling systems. EVA impacts the Lunar Outpost life support system design by requiring a significant increase in the direct supply mass of oxygen and water and by reducing the net mass savings of using dehydrated food. The mass cost of EVA depends on the amount and difficulty of the EVA scheduled.

Training to operate and manage Constellation vehicles, which include a crewed spacecraft and the lunar lander, is an essential part of the Constellation program. This paper discusses the on-going preparations for a Constellation Training Facility (CxTF). CxTF will be compromised of training simulators that will be used, in part, to prepare crew and flight controllers for vehicle operations. Current training simulators are reviewed to identify and outline key CxTF elements, i.e., part-task and full-task trainers. These trainers are further discussed within the context of the Constellation missions.

The “low power-CO2 removal (LPCOR) system” is an advanced air revitalization system that is under development at NASA Ames Research Center. The LPCOR utilizes the fundamental design features of the ‘four bed molecular sieve’ (4BMS) CO2 removal technology of the International Space Station (ISS). LPCOR improves power efficiency by replacing the desiccant beds of the 4BMS with a membrane dryer and a state-of-the-art, structured adsorbent device that collectively require 25% of the thermal energy required by the 4BMS desiccant beds for regeneration. Compared to the 4BMS technology, it has the added functionality to deliver pure, compressed CO2 for oxygen recovery. The CO2 removal and recovery functions are performed in a two-stage adsorption compressor. CO2 is removed from the cabin air and partially compressed in the first stage. The second stage performs further compression and delivers the compressed CO2 to a reduction unit such as a Sabatier reactor for oxygen recovery.