1773 research outputs found
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Formation of Tridymite and Evidence for a Hydrothermal History at Gale Crater, Mars
Full text linkUsing data from Curiosity's instrument suite, we show that the tridymite‐bearing rocks exhibit similar chemical patterns with silicon‐rich alteration zones which crosscut the layered sediments. We infer that the tridymite formed in‐place through hydrothermal processes and show additional chemical and mineralogical results from Gale crater consistent with hydrothermal activity occurring after sediment deposition and lithification.A. S. Yen, R. V. Morris, D. W. Ming, S. P. Schwenzer, B. Sutter, D. T. Vaniman, A. H. Treiman, R. Gellert, C. N. Achilles, J. A. Berger, D. F. Blake, N. I. Boyd, T. F. Bristow, S. Chipera, B. C. Clark, P. I. Craig, R. T. Downs, H. B. Franz, T. Gabriel, A. C. McAdam, S. M. Morrison, C. D. O'Connell‐Cooper, E. B. Rampe, M. E. Schmidt, L. M. Thompson, S. J. VanBommel
Ocean resurge‑induced impact melt dynamics on the peak‑ring of the Chicxulub impact structure, Mexico
Full text linkCore from Hole M0077 from IODP/ICDP Expedition 364 provides unprecedented evidence for the physical processes in effect during the interaction of impact melt with rock-debris-laden seawater, following a large meteorite impact into waters of the Yucatán shelf. Evidence for this interaction is based on petrographic, microstructural and chemical examination of the 46.37-m-thick impact melt rock sequence, which overlies shocked granitoid target rock of the peak ring of the Chicxulub impact structure.Felix M. Schulte, Axel Wittmann, Stefan Jung, Joanna V. Morgan, Sean P. S. Gulick, David A. Kring, Richard A. F. Grieve, Gordon R. Osinski, Ulrich Riller, IODP-ICDP Expedition Science Part
Lunar Exploration Analysis Group (2021)
No full textThe theme of the 2021 Annual Meeting is "Lunar Science and Exploration in the Next Five Years." It will feature updates from NASA HQ, current and planned lunar missions, Commercial Lunar Payload Services (CLPS) providers, and others. The meeting will also engage and showcase the early-career lunar community.Lunar and Planetary Institute Universities Space Research AssociationConvener Amy Fagan, Western Carolina UniversityPARTIAL CONTENTS: New LRO Investigations of Volcanism, Tectonism, and the Lunar Interior / J. D. Stopar, M. E. Banks, C. M. Elder, J. W. Keller, N. E. Petro, A. M. Stickle, and The LRO Team -- Lunar Autonomous Robotic Rover System / T. Sweeney, R. Schrock, J. Hoyt, and J. M. Hurtado -- Electrostatic Dust Analyzer (EDA) for Measuring Dust Transport on the Lunar Surface / X. Wang, Z. Sternovsky, M. Horanyi, J. Deca, I. Garrick-Bethell, W. M. Farrell, J. Minafra, and L. Bucciantini -- Lunar Science and Exploration at Marshall Space Flight Center / R. C. Weber, J. Dankanich, and N. Herrmann -- Lunar Mobility as a Service in the Next Five Years: A Software Perspective / T. J. L. Whitaker, C. Rampolla, C. C. De La Fuente, and M. Provenzano -- The Balance of Aeolian and Hydrologic Processes at Great Sand Dunes, Colorado, USA / A. D. Valdez -- A Survey of Uncommon Yardang Morphologies Around Mars' Medusae Fossae Formation / C. M. Wagoner and K. D. Runyon -- Physical Properties of Sand Grains in the Bagnold Dunes at Gale Crater, Mars / C. M. Weitz, R. J. Sullivan, M. G. A. Lapotre, S. K. Rowland, J. A. Grant, M. M. Baker, and R. A. Yingst -- Investigating the Influence of Dust Storm Directions on Surface Winds via Sand Dune Morphologies in the Northern Mid-Latitudes of Mars / J. M. Widmer and L. K. Fenton -- Venus Antidunes: Lessons from Unconfined Terrestrial Density Currents / K. E. Williams and T. N. Titus --Rediscovery of the Fluid Drag Ripples in Wind Tunnel Experiments / H. Yizhaq, N. Swet, L. Saban, and I. Katra -- Material Properties of Tholin: Implications for Aeolian Processes on Titan / X. Yu, S. M. Horst, C. He, P. Mcguiggan, and X. Zhang -- Three-Dimensional Documentation of the Transition from Sand Ripples to Megaripples / J. R. Zimbelman, S. P. Scheidt, M. M. Baker, and E. Williams
Venus Surface Platform Study Final Report
No full textA main purpose of this Venus Surface Platform Study is to understand platform capabilities required to achieve desired Venus interior-, surface-, and surface-atmosphere-related science. More generally, the original study purpose was to assess the science achievable by various surface platform capabilities, to describe the state of the technologies applicable to Venus surface exploration, and to lay out a high-level roadmap for the future exploration of the planet by this means.Submitted by Tibor Kremic and Mike Amato, co-chairs, Venus Surface Platform Study Team Leads Martha Gilmore, Walter Kiefer, Natasha Johnson, Jonathan Sauder, Gary Hunter, and Thomas ThompsonExecutive Summary -- Introduction -- Venus Surface Science Gaps and Desired Measurements -- Science and Driving Capabilities -- Underlying Technology to Enable Capabilities -- Technology and Infrastructure Development Needs -- The Potential of Future Venus Surface Platforms -- Summary of Overall Findings -- Study Team Membership -- Overview of Science, Capabilities, and Technologies for Expanded Venus Surface Exploration -- References
Introduction—First Billion Years: Habitability
Full text linkThe physical processes active during the first billion years (FBY) of Earth's history, such as accretion, differentiation, and impact cratering, provide constraints on the initial conditions that were conducive to the formation and establishment of life on Earth. This motivated the Lunar and Planetary Institute's FBY topical initiative, which was a four-part conference series intended to look at each of these physical processes to study the basic structure and composition of our Solar System that was set during the FBY. The FBY Habitability conference, held in September 2019, was the last in this series and was intended to synthesize the initiative; specifically, to further our understanding of the origins of life, planetary and environmental habitability, and the search for life beyond Earth. The conference included discussions of planetary habitability and the potential emergence of life on bodies within our Solar System, as well as extrasolar systems by applying our knowledge of the Solar System's FBY, and in particular Earth's early history.Edgard G. Rivera-Valentín, Justin Filiberto, Kennda L. Lynch, Irena Mamajanov, Timothy W. Lyons, Mitch Schulte, and Abel Ménde
Shock impedance amplified impact deformation of zircon in granitic rocks from the Chicxulub impact crater
Full text linkTo resolve issues with the shock petrographic use of zircon, we classified impact deformation features in 429 zircon grains in a continuous drill core of uplifted, granitic bedrock in the peak ring of the 200-km-diameter K-Pg Chicxulub impact structure.Axel Wittmann, Aaron J. Cavosie, Nicholas E. Timms, Ludovic Ferrière, Auriol Raed, Cornelia Rasmussen, Catherine Ross, Daniel Stockli, Martin Schmieder, David A. Kring, Jiawei Zhao, Long Xiao, Joanna V. Morgan, Sean P. S. Gulick, and the IODP-ICDP Expedition 364 Scientist
Globally distributed iridium layer preserved within the Chicxulub impact structure
Full text linkHere, we report new data from four independent laboratories that reveal a positive iridium anomaly within the peak-ring sequence of the Chicxulub impact structure, in drill core recovered by IODP-ICDP Expedition 364. The highest concentration of ultrafine meteoritic matter occurs in the post-impact sediments that cover the crater peak ring, just below the lowermost Danian pelagic limestone. Within years to decades after the impact event, this part of the Chicxulub impact basin returned to a relatively low-energy depositional environment, recording in unprecedented detail the recovery of life during the succeeding millennia. The iridium layer provides a key temporal horizon precisely linking Chicxulub to K-Pg boundary sections worldwide
Near-infrared Reflectance of Rocks at High Temperature: Preliminary Results and Implications for Near-infrared Emissivity of Venus's Surface
Full text linkLight emitted from Venus's surface can be viewed through spectral "windows" in its atmosphere, in the nearinfrared (NIR) around 1000 nanometer (nm) wavelengths. The NIR emissivity of Venus's surface can constrain rock types and their weathering state; emissivities can be measured directly or calculated from reflectances. We measured the reflectances of igneous and sedimentary rocks at Venus's surface temperature, 400 °C–500 °C at 850 and 950 nm; samples were heated in a box furnace in air, illuminated by light-emitting diodes (LEDs), and imaged with a modified charge-coupled device (CCD) camera. Reflectances were also measured at 25 °C from 350 to 1400 nm
Microbial Sulfur Isotope Fractionation in the Chicxulub Hydrothermal System
No full textTarget lithologies and post-impact hydrothermal mineral assemblages in a new 1.3 km deep core from the peak ring of the Chicxulub impact crater indicate sulfate reduction was a potential energy source for a microbial ecosystem (Kring et al., 2020). That sulfate was metabolized is confirmed here by microscopic pyrite framboids with d34S values of -5 to -35 & and DSsulfate-sulfide values between pyrite and source sulfate of 25 to 54 &, which are indicative of biologic fractionation rather than inorganic fractionation processes. These data indicate the Chicxulub impact crater and its hydrothermal system hosted a subsurface microbial community in porous permeable niches within the crater's peak ring
Planetary Geologic Mappers 2021 (LPI Contrib. No. 2610)
No full textThe annual meeting will bring together community members to report progress on geologic mapping projects, discuss a wide range of mapping strategies, and coordinate map-based scientific investigations of planetary surfaces at multiple scales.Conveners Pete Mouginis-Mark, Jim SkinnerPARTIAL CONTENTS: Venus Quadrangles Shimti Tessera (V-11) and Vellamo Planitia (V-12): Implications of the Venus Shield Plains Unit / J. C. Aubele -- Mineralogical and Geomorphological Characterization of a Martian Crater in Northern Meridiani Planum Terrains / B. Baschetti, F. Altieri, C. Carli, A. Frigeri, and M. Sgavetti -- Geomorphic Map (1:10,000) and Science Target Identification in Artemis III AOI 001 and 004 on the Shackleton-de Gerlache Ridge / H. Bernhardt and M. S. Robinson -- Landforms Analysis of a Floor Fractured Crater in Terra Sirenum, Mars / S. Bertoli, M. Massironi, C. Baroni, and M. C. Salvatore -- Mapping a Duck: Geological Features and Region Definitions on Comet 67P/ Churyumov-Gerasimenko / S. Besse, M. Leon-Dasi, B. Grieger, and M. Kueppers -- Improving the Accessibility and Functionality of Planetary Maps Through Web-Based Resources / S. R. Black and J. A. Skinner -- Progress on Geologic Mapping in the Southern Utopia Basin / H. Buban and C. Okubo -- Geologic Mapping (1:60K) of Aeolis Mons, Gale Crater, Mars and Spectral Interpretation of Map Units / D. L. Buczkowski, I. E. Ettenborough, K. D. Seelos, B. J. Thomson, and L. S. Crumpler -- Geologic Map of the Lachesis Tessera Quadrangle (V-18), Venus / D. L. Buczkowski, L. A. Fattaruso, E. M. McGowan, and G. E. McGill -- Status Update on the Inaugural NASA Planetary Geologic Mapping Workshop: Selected for June -- D. M. Burr, J. Wolak Luna, Z. A. Learner Ponterio, J. A. Skinner, and S. R. Black -- Creating Multispectral Mosaics of Mars' South Polar Residual Cap from CRISM Mapping Data / S. F. A. Cartwright, F. P. Seelos, R. T. Poffenbarger, and W. M. Calvin -- Geological Mapping and Stratigraphy of Thrace and Thera Macula, Europa / G. Chiarolanza, G. Mitri, and M. Pondrelli