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Newly outlined missions in the Space Exploration Initiative include extended human habitation on Mars. During these missions, large amounts of waste materials will be generated in solid, liquid and gaseous form. Returning these wastes to Earth will be extremely costly, and will therefore likely remain on Mars. Untreated, these wastes are a reservoir of live/dead organisms and molecules considered to be "biomarkers" i.e., indicators of life). If released to the planetary surface, these materials can potentially confound exobiology experiments and disrupt Martian ecology indefinitely (if existent). Waste management systems must therefore be specifically designed to control release of problematic materials both during the active phase of the mission, and for any specified post-mission duration. To effectively develop waste management requirements for Mars missions, planetary protection guidelines must first be established. While previous policies for Apollo lunar missions exist, it is anticipated that the increased probability of finding evidence of life on Mars, as well as the lengthy mission durations will initially lead to more conservative planetary protection measures. To facilitate the development of overall requirements for both waste management and planetary protection for future missions, a workshop was conducted to identify how these two areas interface, and to establish a preliminary set of planetary protection guidelines that address waste management operations. This paper provides background regarding past and current planetary protection and waste management issues, and their interactions. A summary of the recommended planetary protection guidelines, anticipated ramifications and research needs for waste management system design for both forward (Mars) and backward (Earth) contamination is also provided.

Carbon nanotubes (CNTs) possess extraordinary properties such as high surface area, ordered chemical structure that allows functionalization, larger pore volume, and very narrow pore size distribution that have attracted considerable research attention from around the world since their discovery in 1991. The development and characterization of an original and innovative approach for the control and elimination of gaseous toxins using single walled carbon nanotubes (SWNTs) promise superior performance over conventional approaches due to the ability to direct the selective uptake of gaseous species based on their controlled pore size, increased adsorptive capacity due to their increased surface area and the effectiveness of carbon nanotubes as catalyst supports for gaseous conversion. We present our recent investigation of using SWNTs as catalytic supporting materials to impregnate metals, such as rhodium (Rh), palladium (Pd) and other catalysts. A protocol has been developed to oxidize the SWNTs first and then impregnate the Rh in aqueous rhodium chloride solution, according to unique surface properties of SWNTs. The Rh has been successfully impregnated in SWNTs. The Rh-SWNTs have been characterized by various techniques, such as TGA, XPS, TEM, and FTIR. The project is funded by a NASA Research Announcement Grant to find applications of single walled nanocarbons in eliminating toxic gas Contaminant in life support system. This knowledge will be utilized in the development of a prototype SWNT KO, gas purification system that would represent a significant step in the development of high efficiency systems capable of selectively removing specific gaseous for use in regenerative life support system for human exploration missions.

The elemental composition of food consumed by astronauts is well defined. The major elements carbon, hydrogen, oxygen, nitrogen and sulfur are taken up in large amounts and these are often associated with the organic fraction (carbohydrates, proteins, fats etc) of human tissue. On the other hand, a number of the elements are located in the extracellular fluids and can be accounted for in the liquid and solid waste fraction of humans. These elements fall into three major categories - cationic macroelements (e.g. Ca, K, Na, Mg and Si), anionic macroelements (e.g. P, S and Cl and 17 essential microelements, (e.g. Fe, Mn, Cr, Co, Cu, Zn, Se and Sr). When provided in the recommended concentrations to an adult healthy human, these elements should not normally accumulate in humans and will eventually be excreted in the different human wastes. Knowledge of the partitioning of these elements between the different human waste fractions is important in understanding (a) developing waste separation technologies, (b) decision-making on how these elements can be recovered for reuse in space habitats, and (c) to developing the processors for waste management. Though considerable literature exists on these elements, there is a lack of understanding and often conflicting data. Two major reasons for these problems include the lack of controlled experimental protocols and the inherently large variations between human subjects (Parker and Gallagher, 1988). We have used the existing knowledge of human nutrition and waste from the available literature and NASA documentation to build towards a consensus to typify and chemically characterize the various human wastes. It is our belief, that this could be a building block towards integrating a human life support and waste processing in a closed system.

The success of physico-chemical waste processing and resource recovery technologies for life support application depends partly on the ability of gas clean-up systems to efficiently remove trace contaminants generated during the process with minimal use of expendables. Highly purified metal-impregnated carbon nanotubes promise superior performance over conventional approaches to gas clean-up due to their ability to direct the selective uptake gaseous species based both on the nanotube s controlled pore size, high surface area, and ordered chemical structure that allows functionalization and on the nanotube s effectiveness as a catalyst support material for toxic contaminants removal. We present results on the purification of single walled carbon nanotubes (SWCNT) and efforts at metal impregnation of the SWCNT's.

This paper presents the results from a joint research initiative between NASA Ames Research Center and Lawrence Berkeley National lab. The objective of the research is to produce activated carbon from life support wastes and to use the activated carbon to adsorb and chemically reduce the NO{sub x} and SO{sub 2} contained in incinerator flue gas. Inedible biomass waste from food production is the primary waste considered for conversion to activated carbon. Results to date show adsorption of both NO{sub x} and SO{sub 2} in activated carbon made from biomass. Conversion of adsorbed NO{sub x} to nitrogen has also been observed.

This paper presents the results from a joint research initiative between NASA Ames Research Center and Lawrence Berkeley National lab. The objective of the research is to produce activated carbon from life support wastes and to use the activated carbon to adsorb and chemically reduce the NO(sub x) and SO(sub 2) contained in incinerator flue gas. Inedible biomass waste from food production is the primary waste considered for conversion to activated carbon. Results to date show adsorption of both NO(sub x) and SO(sub 2) in activated carbon made from biomass. Conversion of adsorbed NO(sub x) to nitrogen has also been observed.

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 synergic, technocentric approach estimate 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. Hence, any early missions will require the presence of a closed life support system where all wastes, both solids and liquids, will need to be recycled or where all consumables will need to be supplied. The economics of both are often a matter of speculation and conjecture, but some attempt is made here to evaluate the choice. If a choice is made to completely resupply and eject the waste mass, a number of unknown issues are at hand. On the other hand, processing of the wastes, will enable predictability and reliability of the ecosystem. Solid wastes though smaller in volume and mass than the liquid wastes contains more than 90% of the essential elements required by humans and plants. Further, if left unprocessed they present a serious risk to human health. This paper presents the use of well established technology in processing solid wastes, ensuring that the biogeochemical cycles of ecosystems are maintained, reliability of the closed life support system maintained and the establishment of the early processes necessary for the permanent presence of humans on Mars.