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This study of samples collected from Mars 01 Orbiter was conducted to gain a better understanding and practical experience in methods to process and preserve samples intended for planetary protection analysis. Samples were evaluated for the viable growth of microbes, the molecular biomarker adenosine triphosphate (ATP), and the presence of lipopolysaccharide, a bacterial cell wall component. Losses were observed in the number of viable microbes after freezing as well as in the detectable lipopolysaccharide. Two independent studies of pooled cleanroom samples demonstrate good ATP recovery and consistent values after freezing at −20 °C.

This paper presents the results of theoretical analyses conducted to investigate the potential of various particle removal techniques. The purpose is to limit the extent of cross contamination caused by the small particles generated through in situ handling and processing of simulated Martian rocks. Since the same hardware would be used to process several rocks, the cross contamination is defined as particles transferred from sample to sample as a particulate contaminant. For the purpose of analysis, we assume that during the handling and processing step, rock is crushed using a jaw crusher set at 1 mm gap. The particle distribution of crushed rock is estimated by a Weibull technique. The estimated mass distribution shows that particles in the range of 10 to 100 μm represent approximately 0.5 percent of total weight and they are the major source of the cross contamination. Particles larger than 100 μm are large and easily removed by gravity alone.

In order to meet the National Aeronautics and Space Administration (NASA) planetary protection microbial reduction requirements for all Mars in-situ life detection and sample return missions, entire planetary spacecraft (including planetary entry probe and planetary landing capsules) may have to be exposed to a qualified sterilization process. Presently, dry heat is the only NASA approved sterilization technique available for spacecraft application. However, with the increasing use of various man-made materials, highly sophisticated electronic circuit boards, and sensors in a modern spacecraft, compatibility issues may render this process unacceptable to design engineers and thus impractical to achieve terminal sterilization of entire spacecraft. An alternative vapor phase hydrogen peroxide sterilization process, which is currently used in various industries, has been selected for further consideration.

In order to meet microbial reduction requirements for all Mars in-situ life detection and sample return missions, entire planetary spacecraft (including planetary entry probes and planetary landing capsules) may have to be exposed to a qualified sterilization process. At JPL, we are developing a low temperature (~45°C) vapor phase hydrogen peroxide sterilization process. This process is currently being used by the medical industry and its effectiveness is well established. In order to effectively and safely apply this technology to sterilize a spacecraft, which is made out of various man-made materials and electronic circuit boards, the following technical issues need to be resolved: 1. Efficacy of sterilization process. 2. Diffusion of H2O2 under sterilization process conditions into hard to reach places. 3. Materials and components compatibility with the sterilization process. 4. Development of methodology to protect (isolate) sensitive components (i.e. electronic ) from H2O2 vapor.

Estimates of life-support system mass and power demands were generated using the Life Support Systems Analysis (LiSSA) tool for extra-terrestrial outposts. Parameters varied include the crew size, mission duration, power source, and operating-unit redundancy. Development of promising technologies could reduce launch costs by over $30 million but R&D investment is required. Biological food production technologies are power intensive requiring an order of magnitude more power than physical/chemical air/water regenerative systems. The cost of launching and operating a food production facility is justified by the cost of resupply of food if the mission duration is of the order of several years. A system utilizing food production is, by definition, a highly-recycled and closed-loop system; modeling efforts for such systems should rigorously keep track of all chemical species that have a significant impact on crew survival and processing demands.

A model has been developed for quantitative examination of the integrated operation of a lunar base power system, employing regenerative fuel cell technology, which would lead to incorporation into a lunar base life support system. The model employs methods developed for technology and system trade studies of the Life Support System configuration for the National Aeronautics and Space Administration (NASA). This paper describes the power system and its influence on life support while comparing various technologies, including pressurized gas storage and cryogenic storage, and different operation conditions. Based on preliminary assumptions, the mass, power, and thermal requirement estimates are made at the level of major components. The relative mass contribution and energy requirements of the components in various configurations are presented.

A model is being developed to quantitatively compare and thus assist in the selection of systems and technology options for defined missions envisioned in NASA's Space Exploration Initiative. It consists of a modular top-down hierarchical break-down of the life support systems (LSS) into subsystems, and further break-down of the subsystems into functional elements representing individual processing technologies. A series of papers entitled Human Life Support During Interplanetary Travel & Domicile are planned to describe the techniques and results. Parts I through V have focused on physical/chemical (P/C) Life Support Systems Analysis, with trade-off studies at the systems and technology levels for open and closed loop configurations. This paper discusses an extension to the Generic Modular Flow Schematic (GMFS) for P/C Life Support Systems by the addition of biological (Bio) processes.

Successful operation of life support systems for space exploration missions of the future will require unique sophisticated sensor systems for highly dependable operation, i.e., autonomous and fault tolerant. These sensor systems will require the use of multifunctional in situ sensors that are strategically located throughout the life support systems. These sensors will communicate through control loops that are hierarchically interconnected at several levels of the life support system. Development of the sensor system must be done synergistically with the integration and testing of the subsystems, and their process units, as they are assembled and tested. The plan for proceeding with the sensor systems development and the integration with the test bed assembly and operation is described in this paper.

This paper compares scaleup correlations developed at the Jet Propulsion Laboratory (JPL) and at the Langley Research Center (LaRC) for various life support hardware to estimate mass, volume, and power consumption values as a function of feed or product mass flow rates. The scaleup correlations are provided for a few selected advanced life support technologies developed for the Space Station Freedom (SSF). In addition, correlation validity limits and sources of data on various life support hardware are also discussed.