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Borehole seismic observations from the Chicxulub impact drilling: implications for seismic reflectivity and impact damage
No full textSeismic profiling over geological features reveal to us both the geometry of the structure and the speeds of the seismic waves within it. Calibrating these profiles using only data from the surface, however, remains challenging, but this can be accomplished by making direct seismic measurements in a borehole with a technique called vertical seismic profiling (VSP). Here, we describe the analysis of such a VSP acquired during drilling into the Chicxulub Impact Structure during International Ocean Discovery Program Expedition 364. Special processing of the waves confirm that the strong seismic reflection seen in surface data originates from abrupt changes in the rock properties related to the juxtaposition of hardened sediments, weak suevites, and melt rock. No seismic reflections could be found originating deeper in the uplifted and highly damaged granitoids of the structures's peak ring. As noted in earlier studies, the seismic wave speeds are anomalously low in these lower materials. These speeds were converted into damage indexes and as such this information may provide a means toward constraining advanced numerical impact modeling and in assessing levels of damage in the subsurface in advance of construction on the surfaces of the Moon and Mars.C. G. Nixon, D. R. Schmitt, R. Kofman, J. Lofi, S. P. S. Gulick, S. Saustrup, G. L. Christeson, D. A. Krin
The dynamic atmospheric and aeolian environment of Jezero crater, Mars
No full textDespite the importance of sand and dust to Mars geomorphology, weather, and exploration, the processes that move sand and that raise dust to maintain Mars' ubiquitous dust haze and to produce dust storms have not been well quantified in situ, with missions lacking either the necessary sensors or a sufficiently active aeolian environment. Perseverance rover's novel environmental sensors and Jezero crater's dusty environment remedy this. In Perseverance's first 216 sols, four convective vortices raised dust locally, while, on average, four passed the rover daily, over 25% of which were significantly dusty ("dust devils"). More rarely, dust lifting by nonvortex wind gusts was produced by daytime convection cells advected over the crater by strong regional daytime upslope winds, which also control aeolian surface features. One such event covered 10 times more area than the largest dust devil, suggesting that dust devils and wind gusts could raise equal amounts of dust under nonstorm conditionsClaire E. Newman, Ricardo Hueso, Mark T. Lemmon, Asier Munguira, Álvaro Vicente-Retortillo, Víctor Apestigue, Germán M. Martínez, Daniel Toledo, Rob Sullivan, Ken E. Herkenhoff, Manuel de la Torre Juárez, Mark I. Richardson, Alexander E. Stott, Naomi Murdoch, Agustín Sanchez-Lavega, Michael J. Wolff, Ignacio Arruego, Eduardo Sebastián, Sara Navarro, Javier Gómez-Elvira, Leslie Tamppari, Daniel Viúdez-Moreiras, Ari-Matti Harri, Maria Genzer, Maria Hieta, Ralph D. Lorenz, Pan Conrad, Felipe Gómez, Timothy H. McConnochie, David Mimoun, Christian Tate, Tanguy Bertrand, James F. Bell III, Justin N. Maki, Jose Antonio Rodriguez-Manfredi, Roger C. Wiens, Baptiste Chide, Sylvestre Maurice, Maria-Paz Zorzano, Luis Mora, Mariah M. Baker, Don Banfield, Jorge Pla-Garcia, Olivier Beyssac, Adrian Brown, Ben Clark, Alain Lepinette, Franck Montmessin, Erik Fischer, Priyaben Patel, Teresa del Río-Gaztelurrutia, Thierry Fouchet, Raymond Francis, Scott D. Guzewic
Coordinated Neutron and X-ray Computed Tomography of Meteorites: Detection and Distribution of Hydrogen-Bearing Materials
No full textCalculations referred to in text, and additional color schemesSOM-1: Calculations referred to in text, and additional color scheme
Ancient Venus Conference 2022
No full textThematically, the conference will focus on four main topics, while cementing the discussion around our knowledge of ancient Venus: 1. Accretion history of Venus; 2. Evolution of the volatile inventory and climate on Venus; 3. Habitability of ancient Venus; 4. Geodynamics and surface processes through time.Convener: Allan Treiman, USRA/Lunar and Planetary Institute, Walter Kiefer, USRA/Lunar and Planetary Institute, Science Organizing Committee: Michael Way, NASA Goddard Space Flight Center, Jennifer Whitten, Tulane University, Seth Jacobson, Michigan State University, Marty Gilmore, Wesleyan University, Gabe Eggers, USRA/Lunar and Planetary Institute, Caroline Doumoulin, Université de Nantes, Guillaume Avice, Université de Paris, IPGP, Allan Treiman, USRA/Lunar and Planetary Institute.PARTIAL CONTENTS: Venus, Earth’s Divergent Twin: Observations Constraining the Transition from a Mobile Lid Convection Planet to a Stagnant Lid Convection Planet / W. S. Kiefer and M. B. Weller -- When and How Did Venus Resurfacing Begin? / S. D. King and G. T. Euen -- Adv, Maximal Endurance, VTOL and Sample Return Capable, Mission Agnostic Planetary 4D Explorer[4DPE] / M. K. Kroupa and N. C. Coleman -- Multiple Tectonic and Volcanic Events: Gina Crater Area, Venus / E. K. Roberts, A. H. Treiman, and G. L. Eggers -- Atmospheric Effects on Crater Size: Preliminary Results from a Pilot Study / K. D. Runyon, O. S. Barnouin, N. Izenberg, C. M. Ernst, and A. M. Stickle -- Venus Science and Exploration and Public Engagement: A Proposal / A. J. Shaner, S. R. Buxner, J. Balcerski, N. R. Izenberg, W. S. Kiefer, and A. H. Treiman -- Chemistry of Venus’ Recent Basalts as Clues to its Ancient Past / A. H. Treiman and J. Filiberto -- Day-Night Cloud Asymmetry Inhibits Early Ocean Formation on Venus and Telluric Planets / M. Turbet, J. Leconte, T. Fauchez, F. Selsis, E. Bolmont, B. Charnay, G. Chaverot, / D. Ehrenreich, F. Forget, C. Lovis, E. Marcq, and E. Millour -- Becoming Venus: How the Mantle, Volcanism, and Physics-Backed Models of Global Tectonic Evolution Can Self-Consistently Explain Observations for Venus / M. B. Weller and W. S. Kiefer -- Creating the Bridge: Melting and Volcanism In, and On, Active and Stagnant Lid Planets / M. B. Weller and W. S. Kiefer -- Tesserae: Identifying Distinct Deposits Using Surface Roughness Characteristics Derived from Magellan Data / J. L. Whitten and B. A. Campbell -- Ancient Gases of Ancient Venus / K. J. Zahnle
Downwelling LW Flux and Aerosol Opacity at Jezero Crater, Mars, as Derived from MEDA/TIRS
No full textColumns defined in the first row of each file.This dataset contains the downwelling LW fluxes in the 5–80 microns range and the IR aerosol opacity needed to reproduce and plot the results shown in Figs. 8, 9, 10, 11 and 15 of the manuscript entitled "Surface Energy Budget, Albedo and Thermal Inertia at Jezero Crater, Mars, as Observed from the Mars 2020 MEDA Instrument", currently under review in JGR:Planets
Chirality in organic and mineral systems: a review of reactivity and alteration processes relevant to prebiotic chemistry and life detection missions
No full textChirality is a central feature in the evolution of biological systems, but the reason for biology's strong preference for specific chiralities of amino acids, sugars, and other molecules remains a controversial and unanswered question in origins of life research. Biological polymers tend toward homochiral systems, which favor the incorporation of a single enantiomer (molecules with a specific chiral configuration) over the other. There have been numerous investigations into the processes that preferentially enrich one enantiomer to understand the evolution of an early, racemic, prebiotic organic world. Chirality can also be a property of minerals; their interaction with chiral organics is important for assessing how post-depositional alteration processes could affect the stereochemical configuration of simple and complex organic molecules. In this paper, we review the properties of organic compounds and minerals as well as the physical, chemical, and geological processes that affect organic and mineral chirality during the preservation and detection of organic compounds. We provide perspectives and discussions on the reactions and analytical techniques that can be performed in the laboratory, and comment on the state of knowledge of flight-capable technologies in current and future planetary missions, with a focus on organics analysis and life detection.by Carina Lee, Jessica M. Weber, Laura E. Rodriguez, Rachel Y. Sheppard, Laura M. Barge, Eve L. Berger, and Aaron S. Burto
Advancing IDEA in Planetary Science (2022)
No full textThe planetary science community has initiated the much-needed conversations to delve into the full breadth of IDEA principles. There are many lessons learned and best practices from the experience of other Science, Technology, Engineering, and Mathematics (STEM) fields. For example, the social sciences have revealed some of the psychological and sociological challenges that communities face when confronting and dismantling structural and systemic problems and have provided evidence-based solutions. In this conference, we will bring together the planetary, astrobiological, and social science communities to (1) lean into lessons learned to date, (2) identify opportunities for improvement by listening to those most impacted in our community, and (3) make recommendations for actionable and tangible measures for advancing IDEA principles within planetary science.Co-Conveners: Edgard G. Rivera-Valentín, USRA/Lunar and Planetary Institute, Kennda Lynch, USRA/Lunar and Planetary Institut
Thirteenth Planetary Crater Consortium Meeting : August 10-12, Boulder, Colorado/Virtual
No full textThe annual meeting is designed to present abstracts related to observational, theoretical, experimental, and numerical modeling studies of impact craters on planets, dwarf planets, moons, asteroids, comets, or other small solar system objects.Convener: Stuart Robbins, Southwest Research Institute, Science Organizing Committee: Michelle Kirchoff, Southwest Research Institute, Kassandra Martin-Wells, Ursinus College, Margaret Landis, Laboratory for Atmospheric and Space Physics, University of Colorado, Jamie Riggs Northwestern University, Stuart Robbins, Southwest Research Institute.PARTIAL CONTENTS: Crustal Fragmentation from the Chicxulub Impact: Preliminary Results / A. M. Alexander, B. Johnson, and S. Marchi --Topographic Diffusion of Impact Craters on Mars: Sources, Atmospheric Effects, and Dependence on Climate / B. D. Boatwright, J. W. Head, and M. A. Kreslavsky -- Hypervelocity Airburst Shower Formation of the Pica Glass / M. B. Boslough, P. H. Schultz, and R. S. Harris-- Why Ramparts of Martian Impact Crater are High Relief? / J. M. Boyce and P. J. Mouginis-Mark -- Update on Our Software Simulating Low Angle Skip Impacts — Now 3D and Showing the Ejecta Secondary Impacts / J. A. Burgener -- Distinguishing Impactoclastic From Pyroclastic Layered Rocks on Mars / D. M. Burt -- Exploring Porosity in Asteroid 16 Psyche with 3D Hydrocode Modeling of Its Deepest Impact Structure / W. K. Caldwell, A. Hunter, and C. S. Plesko -- The Mare Protolith Thickness and Competence: A Control of Rocky Crater Populations / M. A. Chertok, P. G. Lucey, E. S. Costello, and S. M. Ireland -- Using Secondary Craters to Assess Strength Differences Between Neighboring Surface Units / J. W. Conrad and C. I. Fassett -- Large Impacts on Icy Bodies s a Feasible Mechanism for Inducing Habitability: The Case of Menrva Crater on Titan / A. P. Crósta, E. A. Silber, R. M. C. Lopes, and M. J. Malaska -- Regime Tracking and Benchmarks for the Impact Modeling Community / M. L. Harwell, S. T. Stewart, R. I. Citron, W. K. Caldwell, and C. S. Plesko -- Modeling Micrometeorite Bombardment into Metal Targets Using the FLAG Hydrocode / M. C. Holmes and W. K. Caldwell --
Update on the Morphometric Measurements for the Robbins Lunar Crater Database / R. H. Hoover, S. J. Robbins, and B. M. Hynek
The Distribution and Accessibility of Geologic Targets near the Lunar South Pole and Candidate Artemis Landing Sites
No full textTransformative lunar science will be driven by the accessibility, recovery, and return to Earth of geological
specimens. Isolated boulders, rock exposures, and rocky craters at the lunar south pole all provide opportunities for
geologic characterization and sampling of the lunar crust. Here, we present the results of orbital geological
mapping of the region surrounding the south pole using Lunar Reconnaissance Orbiter Narrow Angle Camera
images (0.5–2 m pixel−1). We mapped the distribution of isolated boulders (86,896), rocky craters (3556), and rock
exposures (7553) around potential Artemis landing sites 001 and 004 (NASA 2020), which are within or near one
of the Artemis III candidate landing regions. We found that boulder abundance decreases with increasing distance
from the rim of Shackleton crater. From that correlation, we infer that most of the boulders and rock exposures near
Shackleton were deposited as ejecta by the Shackleton impact, and by later the reworking of that material during
smaller impact events. We additionally assessed the accessibility of the mapped features, and documented geologic
targets located on shallow (<15°) slopes, including those on the Shackleton crater rim and on the “Connecting
Ridge” between Shackleton and Henson crater. Such targets could be sampled by a future mission to the lunar
south pole region. Our catalog of mapped features is made available to the lunar community.Sarah. J. Boazman; Jahnavi Shah; Harish; Aleksandra J. Gawronska; Samuel H. Halim; Animireddi V. Satyakumar; Cosette M. Gilmour; Valentin T. Bickel; Natasha Barrett; David A. Krin
Advancing IDEA in Planetary Science
No full textThe Advancing IDEA in Planetary Science Conference was held virtually on April 25 - 29, 2022. A key outcome of this conference was to identify community-led actionable and tangible recommendations to advance IDEA (Inclusion, Diversity, Equity, and Accessibility) principles within the planetary science and astrobiology community. To do this, the conference organized discussions throughout the week into seven Working Groups: (1) Recommendations for Funding Agencies, (2) Recommendations for Universities, (3) Recommendations for Research Groups, (4) Recommendations for Professional Organizations, (5) Recommendations for Employers and about Employment, (6) Recommendations about Safety and Accessibility, and (7) Recommendations about Public Engagement and Outreach. The Working Groups were led by co-facilitators who led asynchronous conversations via Slack and two focused discussion sessions during the conference. After the conference, the Working Groups organized their recommendations into a summary report. This Consensus Report collates and summarizes the recommendations from the seven Working Groups.Version