1773 research outputs found
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Habitability of hydrothermal systems at Jezero and Gusev Craters as constrained by hydrothermal alteration of a terrestrial mafic dike
Full text linkNASA's search for habitable environments has focused on alteration mineralogy of the Martian crust and the formation of hydrous minerals, because they reveal information about the fluid and environmental conditions from which they precipitated. Extensive work has focused on the formation of alteration minerals at low temperatures, with limited work investigating metamorphic or high-temperature alteration. We have investigated such a site as an analog for Mars: a mafic dike on the Colorado Plateau that was hydrothermally altered from contact with groundwater as it was emplaced in the porous and permeable Jurassic Entrada sandstone.Lacey J. Costello, Justin Filiberto, Jake R. Crandall, Sally L. Potter-McIntyre, Susanne P. Schwenzer, Michael A. Miller, Daniel R. Hummer, Karen Olsson-Francis, Scott Per
Hydrothermal precipitation of sanidine (adularia) having full Al,Si structural disorder and specular hematite at Maunakea Volcano (Hawai'i) and at Gale Crater (Mars)
No full textA layer of weathering‐resistant material is located within the walls of an erosional gully of the Pu'u Poliahu cinder cone in the summit region of Maunakea volcano (Hawai'i). The volcanic cone, initially composed of unaltered basaltic material (tephra), was extensively altered throughout by hot, sulfuric‐acid solutions. The layer is a location where the alteration by hot water was particularly aggressive, cementing the volcanic sediment and causing extensive chemical and mineralogical changes. Instead of basaltic chemical and mineralogical compositions, altered tephra was enriched in iron from aqueous precipitation of the mineral hematite (Fe2O3) and was characterized by high sanidine with full structural disorder as the feldspar (instead of plagioclase, which was removed by dissolution) and by Mg‐rich phyllosilicates as additional precipitation products. Hematite, often present as a red pigment in geologic materials, was precipitated from the hot water as specular (i.e., gray) hematite. By analogy, high sanidine and specular hematite at Gale crater (Mars) can be interpreted as alteration products of preexisting Martian basaltic sediment by hot‐water solutions.R. V. Morris, E. B. Rampe, D. T. Vaniman, R. Christoffersen, A. S. Yen, S. M. Morrison, D. W. Ming, C. N. Achilles, A. A. Fraeman, L. Le, V. M. Tu, J. P. Ott, A. H. Treiman, J. V. Hogancamp, T. G. Graff, M. Adams, J. C. Hamilton, S. A. Mertzman, T. F. Bristow, D. F. Blake, N. Castle, S. J. Chipera, P. I. Craig, D. J. Des Marais, G. Downs, R. T. Downs, R. M. Hazen, J.‐M. Morookian, M. Thorp
Asteroids Inside Out: Radar Tomography
No full textThis white paper summarizes the science opportunities, state of the art, and outstanding knowledge gaps, with a particular emphasis on the 99942 Apophis encounter when it flies by within six Earth radii (near the outer geostationary satellite belt) on April 13, 202
Lunar Heat Flow: Global Predictions and Reduced Heat Flux
No full textGeothermal heat flow is a fundamental measure of the internal composition of a planet. On the Moon (which has lost much of its heat of formation, is not strongly tidally heated, and is not likely to have strong mantle convection) surface heat flux results predominantly from the subsurface column abundance of radiogenic material (e.g. U, Th, K…). As U and Th are refractory, the concentration of these elements can be directly related to the refractory composition of the bulk planetary body
Artemis 3 EVA Opportunities along a Ridge Extending from Shackleton Crater towards de Gerlache Crater
No full textEVAs in this location can begin to address science objectives 1c, 2a, 3a, 3b, 3d, 4a, 4d, 6c, and 7b, and potentially address objectives 1a, 1b, 4b, 5a-b, and 7d [12]. EVAs can also help address strategic knowledge gaps (SKGs) I-D, I-G, II-D-3, III-C-2, III-D-1, III-D-2, III-D-4, and III-J-4 of the Scientific Context for Exploration of the Moon. National Academies Press, Washington D. C.David A. Kring; Natasha Barrett; Sarah J. Boazman; Aleksandra Gawronska; Cosette M. Gilmour; Samuel H. Halim; Harish; Katie McCanaan; Animireddi V. Satyakumar; Jahnavi Sha
Science Priorities for Sample Return for Artemis Missions to the Lunar South Pole
No full textSamples are needed to address scientific as well as engineering knowledge gaps. Samples collected during the Apollo missions have been studied for five decades and continue to be investigated vigorously. Because of the lasting importance of the samples and to ensure that samples returned to Earth maintain their integrity, curation of the samples is also a crucial activity. In this white paper, we address the key science priorities for which samples are needed.B. L. Jolliff, J. Gross, C. K. Shearer, J. W. Head, T. J. Lapen, C. A. Crow, J. J. Barnes, and J. L. Mitchel
High-pressure metamorphic mineralogy of the Martian crust with implications for density and seismic profiles
No full textHere, we calculate the mineralogy of the Martian lower crust and upper mantle as a function of pressure and temperature with depth using four bulk compositions (average crust, Gusev basalt, olivine-phyric shergottite, and primitive average mantle). We then use this mineralogy to extract rock properties such as density and seismic velocities, describe their changes with varying conditions and geotherms, and make predictions for the crust–mantle boundary
Geologic context and potential EVA targets at the lunar south pole
No full textThe Artemis human landing system concept of operations is initially limited to two astronauts who land "on the lunar south pole" and will not exceed a surface stay of 6.5 days near the south pole (NASA, 2019a). Potentially, five extravehicular activities (EVAs) are possible in that interval (NASA, 2019b). Landing, traverses by crew and supporting robotic assets, and targeted sampling of the region require pre-mission geologic assessments of the lunar south pole. Here, we provide an initial geologic assessment of the lunar south pole, Shackleton crater, and the geology that may be accessible in that type of short duration surface stay
Small Bodies Tell the Story of the Solar System: A Scientific Rationale for a Multi-Target Small Body Sample Return Program including the Earth-based Laboratory Analysis of Returned Samples
No full textA White Paper submitted to the Planetary Science and Astrobiology Decadal Survey 2023-203
Maximizing the Value of Solar System Data through Planetary Spatial Data Infrastructures
No full textPlanetary Spatial Data Infrastructure (PSDI) is a collection of data, tools, standards, policies, and the people that use and engage with them. A PSDI comprises an overarching support system for planetary spatial data. PSDIs (1) establish effective plans for data acquisition; (2) create and make available higher-order products; and (3) consider long-term planning for correct data acquisition, processing and serving (including funding). PSDIs improve the potential for correlating existing and future datasets in ways that will increase the overall scientific return, enable new research activities and inspire the general public and next generation scientists. We recommend that Planetary Spatial Data Infrastructures be created for all bodies and key regions in the Solar System.Primary Author: Jani Radebaugh, Chair, Mapping and Planetary Spatial Infrastructure Team (MAPSIT), Brigham Young University, [email protected], (801) 422-9127 ; coauthors: The MAPSIT Steering Committee: Brad Thomson, Vice-Chair, University of Tennessee Knoxville; Brent Archinal, U. S. Geological Survey; Ross Beyer, SETI Institute, NASA Ames; Dani DellaGiustina, U of Arizona Lunar and Planetary Laboratory; Caleb Fassett, Marshall Space Flight Center; Lisa Gaddis, U. S. Geological Survey; Sander Goossens, Goddard Space Flight Center; Trent Hare, U. S. Geological Survey; Jay Laura, U. S. Geological Survey; Pete Mouginis-Mark, SOEST, University of Hawaii; Andrea Naß, Deutsches Zentrum für Luft- und Raumfahrt; Alex Patthoff, Planetary Science Institute; Julie Stopar, Lunar and Planetary Institute; Sarah Sutton, U of Arizona Lunar and Planetary Laboratory; David Williams, SESE, Arizona State University; Justin Hagerty (ex officio), Director, Astrogeology Science Center, U. S. Geological Survey; Louise Prockter (ex officio), Planetary Data System lead scientist, Lunar and Planetary Institut