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The baseline Environmental Control and Life Support System (ECLSS) for the International Space Station (ISS) includes regenerative and non-regenerative technologies for Temperature and Humidity Control (THC), Atmosphere Control and Supply (ACS), Fire Detection and Suppression (FDS), Atmosphere Revitalization (AR), Water Recovery and Management (WRM), Waste Management (WM), and Vacuum System (VS). The U.S. Lab module will contain complete THC and ACS subsystems and an open loop AR including a Carbon Dioxide Removal Assembly (CDRA), Trace Contaminant Control Subassembly (TCCS), and a Major Constituent Analyzer (MCA). An Oxygen Generation Assembly (OGA) is added with the U. S. Hab module, along with the WRM and WM subsystems. The final baseline configuration is a closed water loop and partially closed atmosphere loop and represents the best available mature technologies.

Eight SUMMA passivated sampling canisters were shipped to the Russian Space Station Mir in February of 1995 to assess ambient trace contaminant concentrations. Prior to flight, the canisters were injected with isotope labeled surrogates and internal standards to measure potential negative impacts on measurement accuracy caused by the trip environmental conditions of launch and return. Three duplicate canister samples were collected in parallel with Russian sorbent samples to acquire data for comparative purposes. A total of 32 target and 13 non-target volatile compounds were detected in each of the samples analyzed. The concentrations of the compounds remained relatively consistent for the three sampling events, and all of the concentrations of detected contaminants were well below both US and Russian Spacecraft Maximum Allowable Concentrations (SMAC). Five different fluorocarbons were consistently detected at relatively high concentrations.

In an era of tight fiscal constraints, research and development funds are not sufficient to study all possible avenues for technology development. Hence, development priorities must be set and funding decisions made based on the projected benefits which will arise from fully developing different technologies. In order to identify promising development initiatives for advanced thermal control systems, a study was conducted which quantified the potential mass savings of various technologies. Assessments were made for five reference missions considered to be likely candidates for major human space flight initiatives beyond the International Space Station. The reference missions considered were Space Station Evolution, Space Shuttle Replacement, First Lunar Outpost Lander, Permanent Lunar Base, and Mars Lander. For each mission a baseline active thermal control system was defined and mass estimates were established.

The appropriate role of human testing in life support systems design has been a key concern for human spacecraft development. This discussion intensified over the past one and a half years as the International Space Station (ISS) evaluated the risk associated with the baseline program while conducting cost and schedule convergence activities. The activity was carried from the traditional top-level discussion to evaluation of the specific Space Station Life Support concerns associated with human interaction, weighed against cost impacts. This paper details the results of this activity, providing the rationale for the present ISS approach.

The Environmental Control and Life Support System (ECLSS) is distributed throughout the International Space Station (ISS) pressurized modules. Five International Partners (IP) are designing ECLSS hardware: National Aeronautics and Space Agency (NASA), Russian Space Agency (RSA), European Space Agency (ESA), National Space Development Agency of Japan (NASDA), and one International Participant-Italian Space Agency (ASI). Two U. S. Product Group (PG) contractors are designing ECLSS hardware and outfitting modules. Each contractor has subcontractors and vendors designing hardware. These factors contribute to the magnitude of the ECLSS interface integration across ISS. During assembly of ISS, some pressurized modules change on-orbit locations. All of these interfaces are reviewed and defined, if unique, to ensure compatibility. However, this paper will focus on the final configuration of ISS. ISS is composed of various pressurized modules that provide a variety of capabilities.

The International Space Station (ISS) Program has been divided into three distinct stages. The first phase of the program performs risk mitigation experiments during the joint Shuttle - MIR missions. The second stage establishes a point in the program where the United States Laboratory will have the capability to support initial research, the Italian Mini-Pressurized Logistic module will provide the capability to help resupply the ISS and the United States Node and Laboratory module in conjunction with the Russian Functional Cargo Block (FGB) and Service Module (SM) will have the capability to support up to three crew members continuously on-orbit. The final phase of the program will complete the Russian and the U.S. segments and will add the Japanese and the European modules to ISS. At the end of stage three ISS will also have the capability to support up to six crew members continuously.

The ultimate goal of human space exploration is to discover if life exists on other worlds, to understand the genesis and evolution of the universe and to learn to live on other planets. Mars offers the closest opportunity to pursue these goals realistically. The capabilities to define, design, develop, build, test, contract out, manufacture and operate new technologies are the means to achieve this set of goals. The purpose of this set of criteria is to evaluate mission design and exploration technology proposals to ensure that the means support the goals and do no obstruct them. This paper presents a comprehensive approach to evaluating complete Mars mission designs and partial designs. It begins from current theory and methodology of design problem definition. It proposes a method of evaluating if the mission design solution answers the problem definition.

The lunar-solar power system features collection of solar radiation on the moon and conversion to RF or laser beams for power transmission to earth receivers for rectification. The subsystems are similar to those proposed for satellite solar power systems but there are significant differences for the transmitting apertures and receiver systems (rectennas). The latter are designed to operate over a wide angular range of beam directions (up to 120°). Two methods of single axis tracking have been identified [2]; these use either: 1) stationary reflector elements, or 2) modular tracking units. Both methods use cylindric optics to concentrate the power beams and their properties are discussed.

This paper will demonstrate design of a Mars transit/surface habitat, beginning with composition of the private living spaces, using established proportioning systems. The living spaces will be used as basis for the overall design of a habitation module transported to low Earth orbit individually by a Shuttle type vehicles, or as a fully integrated spacecraft in an Energiya class HLLV. The high degree of order achieved will enable full assimilation of all systems necessary to sustain six crew members for approximately 1000 days and provide living space greater than that currently recommended for long duration missions.

This paper questions the widely held assumption that a single crew habitat can serve equally well as both an interplanetary vehicle and as a Mars surface habitat. This paper argues that these two uses and the designs to support them are so fundamentally different that it is not possible to serve both optimally with the same habitat element. This distinction leads to a reassessment of the Mars Direct approach and similar mission architectures. As an alternative, this paper presents the Being There versus Getting There (BTvGT) approach, so-named because it comprehends the distinction between the two habitats and the mission scenarios that they support. The first distinction is the emphasis upon placing optimal facilities upon the Mars surface and in the interplanetary vehicle, even at the cost of greater total mission launch mass. This shift signifies a focus upon the quality and content of the masses involved, rather than just total undifferentiated tonnage delivered to the surface.

The paper submits the description and the temperature performances of an autonomous adsorption refrigerator. The volume of the chamber is equal to 7 litres. As the refrigerant was used the distilled water. It is shown, that such device can support the lowered temperature in the chamber without use of source of energy during 12 hours. To obtain the lower temperature in the evaporator, the thermal and sorption characteristics of the sorbent bed with active carbon - acetone pair were studied. The possibility of thermal control over refrigerating capacity and of the provision of uniform heat output from the evaporator is illustrated.

A cross-discipline approach is undertaken to establish, in a small lunar crater, a permanent domed oasis which optimizes human factors. A satellite first performs global mapping prior to site selection. It will transfer to lunar-stationary orbit and transmit power to the base via laser beam to drive equipment and illumine the long lunar night. Tele-robotic operations minimize risk during heavy construction prior to occupancy. A coring penetrator tunnels habitats in the crater wall which allow an elevated outlook towards the agricultural interior ground plane. A sustained trial period monitors controlled plant growth prior to the introduction of other life forms.

The external active thermal control system (ATCS) of International Space Station (ISS) in the assembly-complete configuration has 24 radiator panels on each side, designed to reject the Station's waste heat to deep space. The radiators use liquid ammonia as the working fluid. The effective sink temperature of the radiators may vary from -112° C to 116° C (-170° F to 240° F) depending on several factors including the orbit parameters and attitude and orientation of the Station. At sink temperatures below the ammonia freezing point of -77.7° C (-107.9° F) and low heat load conditions, the radiator flow tubes may freeze. Therefore, the radiators are designed to withstand freezing and thawing. The purpose of this study is to develop a detailed SINDA/FLUINT model of the ATCS radiators and use it to predict the freeze/thaw cycles of the radiator flow tubes at extremely cold environments, and examine its impact on the performance of the ATCS loop.

National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) requires the maximum analytical temperature limit for solar array drive (SAD) slip rings to be 50°C based on previous flight programs. With the baseline thermal control, the Landsat-7 peak slip ring temperature prediction significantly exceeded the requirement. The initial options of changing the slip ring assembly shaft material from titanium to aluminum or filling the hollow center of the titanium shaft with copper could reduce the slip ring temperature significantly. However, they have high technical risks and significant impacts on the program cost and schedule. This paper presents low-risk and low-cost thermal changes to reduce the peak slip ring temperature prediction to below 50°C.

A BRIC (Biological Research In a Canister) experiment to investigate the effects of reduced gravity at the molecular level using Arabidopsis has been initiated. To ensure an efficient BRIC experiment, a series of ground-based studies have been conducted. These studies were designed to determine: 1) the ideal seed density to obtain enough plant tissue from a single canister; 2) optimum germination surface for tissue recovery after freezing in liquid nitrogen; 3) yield and quality of mRNA from small amounts of tissue; 4) time point to freeze the seedlings; and 5) changes in gene expression that may be caused by stresses during launch.

The International Space Station (ISS) will have, upon completion, a large suite of international facilities that can be utilized for plant research from cell and tissue culture to intact plants. Characteristics and capabilities of the various plant related facilities being developed in the United States and by our international partners will be described in the order of their current launch sequence. An overview will also be presented of support equipment and facilities such as the life science glove box and 2.5 meter centrifuge. A critical feature of plant research on ISS will be the ability to have controls as well as conduct long term and repetitive experiments.

Five potato (Solanum tuberosum L.) leaf cuttings were flown on STS-73 in late October, 1995 as part of the 16-day USML-2 mission. Pre-flight studies were conducted to study tuber growth, determine carbohydrate concentrations and examine the developing starch grains within the tuber. In these tests, tubers attained a fresh weight of 1.4 g tuber-1 after 13 days. Tuber fresh mass was significantly correlated to tuber diameter. Greater than 60% of the tuber dry mass was starch and the starch grains varied in size from 2 to 40 mm in the long axis. For the flight experiment, cuttings were obtained from seven-week-old Norland potato plants, kept at 5°C for 12 hours then planted into arcillite in the ASTROCULTURE™ flight hardware. The flight package was loaded on-board the orbiter 22 hours prior to launch.

Results obtained during the shuttle mid-deck locker experiment CHROMEX-03 suggested that failure of reproductive development of plants during spaceflight was related to a limitation in availability of metabolic gases to developing tissues due to the lack of convective air movement in microgravity. The purpose of this ground-based experiment was to determine the effect of different O2 and CO2 concentrations on plant reproductive development and growth. Fourteen day old Arabidopsis thaliana (L.) Heynh plants were grown as for the spaceflight experiment and exposed for six days to either air or one of six different air/nitrogen dilutions. Growth and reproductive responses to treatments of less than 50 mL·L-1 O2, 100 μL·L-1 CO2 were significantly different (P=0.05) from each other and all other treatments, while responses to treatments with greater than 140 mL·L-1 O2, 300 μL·L-1 CO2 were not significantly different from the air treatment.

The International Space Station (ISS) Active Thermal Control System uses a single phase liquid ammonia system to collect and reject waste heat from the various space station systems. The expected cold environments in which the Heat Rejection Subsystem (HRS) radiators of the heat rejection system are to operate fall as low as -102.8 °C (-153 °F). Because the ammonia working fluid freezes at -77.7 °C (-108 °F) and since the environment temperatures are to remain below this level for 30 minutes per orbit, design approaches have been identified, implemented, and tested to ensure that the ISS Active Thermal Control System radiators will perform under these environments. There are several items of concern in a freeze-tolerant design. The flow tubes imbedded in the panel, from which heat is rejected, must be designed to tolerate potentially high pressure during a thaw. The supply and return manifold tubing must be designed to prevent ammonia from freezing within them.

The paper discusses the potentialities of the plasmo-ozonocatalytic system of microcontaminants (MC) removal from space orangery atmosphere. Atmosphere contaminated by vapours of MC was vented through a purifier consisted of a plasmochemical, ozonocatalytic and chemosorbed units. It was shown the process of decomposition of contaminants is connected with formation of the strong oxidizing and unequilibrium medium. Kinetic mechanism of plasmochemical decomposition of MC is discussed within the framework of radical mechanism. The paper describes a construction and results of the examination of the new filter for contaminants removal from orangery atmosphere. It was shown a broad potentialities of the filter for using it in the orangery gas recycle system.