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Operational issues encountered by Apollo astronauts relating to lunar dust were catalogued, including material abrasion that resulted in scratches and wear on spacesuit components, ultimately impacting visibility, joint mobility and pressure retention. Standard methods are being developed to measure abrasive wear on candidate construction materials to be used for spacesuits, spacecraft, and robotics. Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. Custom tips were fabricated from terrestrial counterparts of lunar minerals for scratching Al 6061-T6 and comparing to standard diamond scratches. Considerations are offered for how to apply standards when selecting materials and developing dust mitigation strategies for lunar architecture elements.

A terrestrial analog device was developed to test the performance of a proposed lunar regolith-based water filtration design. To support this study, the flow behavior of tracer particles passing through a glass bead media filter was evaluated on NASA's reduced gravity aircraft in simulated microgravity and lunar gravity environments. The flight results were then compared to tests conducted using a novel application of a clinostat tilted ∼10 degrees from horizontal to simulate a lunar gravity vector fraction (1/6 of Earth's gravity, or 0.17g) acting axially on the fluid system. Phase I was designed to examine large particle fluidization and sedimentation characteristics, and showed that with relatively large particles, a sedimentation layer formed in the inclined clinostat similar to the true reduced gravity environment.

Electrochromic devices offer potential benefit as variable emissivity radiators for advanced extravehicular activity (EVA) suits. Supplementing (or even replacing) the water sublimator with radiators will result in reduced mass consumption for heat rejection, and radiators can be effective in environments where sublimation is not possible. The exotic properties of electrochromic devices (ECDs) may also lead to radiators that are capable of adapting, without mechanical actuation, to changing EVA operations and environments. Three concepts for the implementation of flexible electrochromic radiators are presented, along with a preliminary thermal analysis for each configuration.

The most basic design requirements for a space habitat intended for human occupancy are to provide the crew with the necessary metabolic consumables, remove undesirable waste products, and maintain environmental conditions that are conducive to life, health and operations. Propulsive transportation of the habitat to its desired location, either in orbit or to a planetary surface, and either with or without a crew onboard during transit, represents the next fundamental design driver. Both of these spacecraft elements are typically characterized by a common denominator expressed in terms of launch mass, and can be optimized against various parameters for risk mitigation and operational enhancement. This paper outlines a graduate curriculum developed within an academic focus area termed Bioastronautics in the Aerospace Engineering Sciences Department at the University of Colorado (CU).

Access systems for partial gravity planetary exploration are described that may allow humans in spacesuits safe access to scientifically significant terrain on the Moon and Mars. Contingency scenarios are presented for effective rescue of astronauts from flat and sloped terrain. Conclusions and recommendations are offered for Earth-based field testing and potential inclusion of access systems in the larger Lunar surface system architecture.

An eventual return to colonize the Moon or the launch of a human exploration mission to Mars will drive the need for developing novel surface Extravehicular Activity (EVA) technologies as well as require new operational and planning techniques. These advances are necessary to enable safe EVA access to the planetary surface locales that are most likely to yield exciting scientific knowledge, such as in the sedimentary deposit regions recently found on Mars or within and around large craters formed from asteroid collisions; as these represent the areas thought most likely to contain fossilized evidence of life or geological information pertaining to the origins and age of the planets. These sites, while rich in potential for scientific discovery, also introduce challenging terrain for exploration by surface EVA teams.

This study investigated the possibility of detecting water deficit stress in plants by using optical signals collected from leaves. Two theoretical approaches have been investigated. In principle, chlorophyll fluorescence can be used to measure generally stressful situations in plants. Our review, however, found that simple ratios of coarsely time-resolved chlorophyll fluorescence, such as maximum fluorescence over fluorescence at steady state, appear to be incapable of adequately distinguishing water stress from other stress factors. A second principle being investigated involves correlation of light absorption within leaves to leaf-water-content using water absorbing and non-water absorbing wavelengths. Our investigation concentrated on defining and eliminating as many extraneous variables as possible.

Forty to seventy percent of astronauts and cosmonauts reportedly exhibit undesirable vestibular disturbances during the first few days of exposure to weightlessness, including Space Motion Sickness (SMS) and perceptual illusions. While SMS is the primary concern for short-duration missions, the effect of perceptual illusions during landing may be particularly problematic following long-duration missions such as returning from the International Space Station (ISS), or a Mars mission, where vestibular, perceptual and sensorimotor adaptation to 1g, to 0g, to 0.38g has occurred. The longer the mission, the more complete the adaptation is to hypogravity and the more severe the perceptual errors and sensorimotor control disturbances.

The Biological Wastewater Processor Experiment Definition team is performing the preparatory ground research required to define and design a mature space flight experiment. One of the major outcomes from this work will be a unit-gravity prototype design of the infrastructure required to support scientific investigations related to microgravity wastewater bioprocessing. It is envisioned that this infrastructure will accommodate the testing of multiple bioprocessor design concepts in parallel as supplied by NASA, small business innovative research (SBIR), academia, and industry. In addition, a systematic design process to identify how and what to include in the space flight experiment was used.

It is hypothesized that the weightless environment experienced during space flight has a stimulating effect on the growth rate of microorganisms. This theory was tested with the bacterium Escherichia coli using protocols and supporting hardware evolved over five space shuttle missions between April, 1991 and July, 1993. In comparing 38 bacterial growth experiments across multiple flights, the overall average population density of E. coli achieved in space was 88% greater than that of matched ground controls (N=19 flight, 19 ground, p < 0.05). Depending on test variables, growth increases in space of up to 257% over ground controls were observed. Analysis of bacterial proteins by gel electrophoresis indicated an apparent difference in expressed protein between flight and ground control E. coli samples in the range of 20-30 kD.

Extravehicular Activity (EVA) based from the Space Station Freedom presents unique conditions in which a space suit must operate. To accommodate the predicted demands, new technology is required in many aspects of the suit design. The requirements associated with Space Station EVA are addressed and an overview of various technology concepts is given. Two candidate space suits are presented and the methods used to evaluate their performance characteristics are described.