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[1] We studied visible to near-infrared (VNIR, 0.35-2.5 mm) and middle infrared (MIR, 1800-250 cm À1 , also called thermal infrared and vibrational) spectra of basaltic tephras from Mauna Kea volcano that were altered under ambient, hydrothermal (hydrolytic and acid sulfate), and dry heat conditions. Although models of MIR spectra of altered tephras generally produce fits whose quality is reduced compared to deconvolutions of primary lithologies, they successfully identify major alteration phases (cristobalite, oxide, phyllosilicate, and sulfate) except in palagonites. MIR spectra of the <45 mm fraction of all altered tephra samples exhibit an H 2 O peak at $1640 cm À1 , but it cannot be used as an indicator of H 2 O content. This feature is present with band strengths >1% in spectra of the 500-1000 mm fraction only if phyllosilicates are present. Although Mauna Kea palagonitic tephra is considered a VNIR analog to Martian dust, comparison of MIR altered tephra spectra (<45 mm fraction) to dust spectra retrieved from Mars Global Surveyor and Mars Exploration Rover instruments do not provide good spectral matches. The best MIR match is a tephra that has a strong plagioclase feldspar transparency feature and was altered under dry, high-temperature, oxidizing conditions. This sample is not a VNIR analog and is not a process analog, but it emphasizes the mineralogical importance of plagioclase feldspar in Martian dust. No single tephra is a good spectral analog across the VNIR and MIR. We found no evidence for substantial sulfates or phyllosilicates in Mini-Thermal Emission Spectrometer (Mini-TES) spectra from Gusev Crater.Citation: Hamilton, V. E., R. V. Morris, J. E. Gruener, and S. A. Mertzman (2008), Visible, near-infrared, and middle infrared spectroscopy of altered basaltic tephras: Spectral signatures of phyllosilicates, sulfates, and other aqueous alteration products with application to the mineralogy of the Columbia Hills of Gusev Crater, Mars,

This article is a U.S. government work, and is not subject to copyright in the United States. CrossMark a r t i c l e i n f o b s t r a c tDesert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona on the San Francisco Volcanic Field. These activities are designed to exercise planetary surface hardware and operations in conditions where long-distance, multi-day roving is achievable, and they allow NASA to evaluate different mission concepts and approaches in an environment less costly and more forgiving than space. The results from the RATS tests allow selection of potential operational approaches to planetary surface exploration prior to making commitments to specific flight and mission hardware development. In previous RATS operations, the Science Support Room has operated largely in an advisory role, an approach that was driven by the need to provide a loose science mission framework that would underpin the engineering tests. However, the extensive nature of the traverse operations for 2010 expanded the role of the science operations and tested specific operational approaches. Science mission operations approaches from the Apollo and Mars-Phoenix missions were merged to become the baseline for this test. Six days of traverse operations were conducted during each week of the 2-week test, with three traverse days each week conducted with voice and data communications continuously available, and three traverse days conducted with only two 1-hour communications periods per day. Within this framework, the team evaluated integrated science operations management using real-time, tactical science operations to oversee daily crew activities, and strategic level evaluations of science data and daily traverse results during a post-traverse planning shift. During continuous communications, both tactical and strategic teams were employed. On days when communications were reduced to only two communications periods per day, only a strategic team was employed. The Science Operations Team found that, if communications are good and down-linking of science data is ensured, high quality science returns is possible regardless of communications. What is absent from reduced communications is the scientific interaction between the crew on the planet and the scientists on the ground. These scientific interactions were a critical part of the science process and significantly improved mission science return over reduced communications conditions. The test also showed that the quality of science return is not measurable by simple numerical quantities but is, in fact, based on strongly non-quantifiable factors, such as the interactions between the crew and the Science Operations Teams. Although the metric evaluation data suggested some trends, there was not sufficient granularity in the data or specificity in the metrics to allow those trends to be understood on numerical data alone.Published by Elsevier Ltd. on behalf of IAA.

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