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1. Astrobiological Potential of Rocks Acquired by the Perseverance Rover at a Sedimentary Fan Front in Jezero Crater, Mars

Author

T. Bosak, D. L. Shuster, E. L. Scheller, S. Siljeström, M. J. Zawaski, L. Mandon, J. I. Simon, B. P. Weiss, K. M. Stack, E. N. Mansbach, A. H. Treiman, K. C. Benison, A. J. Brown, A. D. Czaja, K. A. Farley, E. M. Hausrath, K. Hickman‐Lewis, C. D. K. Herd, J. R. Johnson, L. E. Mayhew, M. E. Minitti, K. H. Williford, B. V. Wogsland, M.‐P. Zorzano, A. C. Allwood, H. E. F. Amundsen, J. F. Bell III, K. Benzerara, S. Bernard, O. Beyssac, D. K. Buckner, M. Cable, F. Calef III, G. Caravaca, D. C. Catling, E. Clavé, E. Cloutis, B. A. Cohen, A. Cousin, E. Dehouck, A. G. Fairén, D. T. Flannery, T. Fornaro, O. Forni, T. Fouchet, E. Gibbons, F. Gomez Gomez, S. Gupta, K. P. Hand, J. A. Hurowitz, H. Kalucha, D. A. K. Pedersen, G. Lopes‐Reyes, J. N. Maki, S. Maurice, J. I. Nuñez, N. Randazzo, J. W. Rice Jr., C. Royer, M. A. Sephton, S. Sharma, A. Steele, C. D. Tate, K. Uckert, A. Udry, R. C. Wiens, and A. Williams

Subjects
Mars, sedimentary geochemistry, planetary geochemistry, origin of life, hydrothermal systems and weathering on other planets, hydrology and fluvial processes, Geology, QE1-996.5, Geophysics. Cosmic physics, QC801-809
Abstract

Abstract The Perseverance rover has collected seven oriented samples of sedimentary rocks, all likely older than the oldest signs of widespread life on Earth, at the exposed base of the western fan in Jezero crater, Mars. The samples include a sulfate‐ and clay‐bearing mudstone and sandstone, a fluvial sandstone from a stratigraphically low position at the fan front, and a carbonate‐bearing sandstone deposited above the sulfate‐bearing strata. All samples contain aqueously precipitated materials and most or all were aqueously deposited. Although the rover instruments have not confidently detected organic matter in the rocks from the fan front, the much more sensitive terrestrial instruments will still be able to search for remnants of prebiotic chemistries and past life, and study Mars's past habitability in the samples returned to Earth. The hydrated, sulfate‐bearing mudstone has the highest potential to preserve organic matter and biosignatures, whereas the carbonate‐bearing sandstones can be used to constrain when and for how long Jezero crater contained liquid water. Returned sample science analyses of sulfate, carbonate, clay, phosphate and igneous minerals as well as trace metals and volatiles that are present in the samples acquired at the fan front would provide transformative insights into past habitable environments on Mars, the evolution of its magnetic field, atmosphere and climate and the past and present cycling of atmospheric and crustal water, sulfur and carbon.

Published
2024
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2. Geology of the InSight landing site on Mars

Author

M. Golombek, N. H. Warner, J. A. Grant, E. Hauber, V. Ansan, C. M. Weitz, N. Williams, C. Charalambous, S. A. Wilson, A. DeMott, M. Kopp, H. Lethcoe-Wilson, L. Berger, R. Hausmann, E. Marteau, C. Vrettos, A. Trussell, W. Folkner, S. Le Maistre, N. Mueller, M. Grott, T. Spohn, S. Piqueux, E. Millour, F. Forget, I. Daubar, N. Murdoch, P. Lognonné, C. Perrin, S. Rodriguez, W. T. Pike, T. Parker, J. Maki, H. Abarca, R. Deen, J. Hall, P. Andres, N. Ruoff, F. Calef, S. Smrekar, M. M. Baker, M. Banks, A. Spiga, D. Banfield, J. Garvin, C. E. Newman, and W. B. Banerdt

Subjects
Science
Abstract

The InSight spacecraft landed on Mars on November 2018. Here, the authors characterize the surficial geology of the landing site and compare with observations and models derived from remote sensing data prior to landing and from ongoing in situ geophysical investigations of the subsurface.

Published
2020
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3. Location and Setting of the Mars InSight Lander, Instruments, and Landing Site

Author

M. Golombek, N. Williams, N. H. Warner, T. Parker, M. G. Williams, I. Daubar, F. Calef, J. Grant, P. Bailey, H. Abarca, R. Deen, N. Ruoff, J. Maki, A. McEwen, N. Baugh, K. Block, L. Tamppari, J. Call, J. Ladewig, A. Stoltz, W. A. Weems, L. Mora‐Sotomayor, J. Torres, M. Johnson, T. Kennedy, and E. Sklyanskiy

Subjects
Mars, Mars lander, location, InSight, surface location, Astronomy, QB1-991, Geology, QE1-996.5
Abstract

Abstract Knowing precisely where a spacecraft lands on Mars is important for understanding the regional and local context, setting, and the offset between the inertial and cartographic frames. For the InSight spacecraft, the payload of geophysical and environmental sensors also particularly benefits from knowing exactly where the instruments are located. A ~30 cm/pixel image acquired from orbit after landing clearly resolves the lander and the large circular solar panels. This image was carefully georeferenced to a hierarchically generated and coregistered set of decreasing resolution orthoimages and digital elevation models to the established positive east, planetocentric coordinate system. The lander is located at 4.502384°N, 135.623447°E at an elevation of −2,613.426 m with respect to the geoid in Elysium Planitia. Instrument locations (and the magnetometer orientation) are derived by transforming from Instrument Deployment Arm, spacecraft mechanical, and site frames into the cartographic frame. A viewshed created from 1.5 m above the lander and the high‐resolution orbital digital elevation model shows the lander is on a shallow regional slope down to the east that reveals crater rims on the east horizon ~400 m and 2.4 km away. A slope up to the north limits the horizon to about 50 m away where three rocks and an eolian bedform are visible on the rim of a degraded crater rim. Azimuths to rocks and craters identified in both surface panoramas and high‐resolution orbital images reveal that north in the site frame and the cartographic frame are the same (within 1°).

Published
2020
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4. An Impact Crater Origin for the InSight Landing Site at Homestead Hollow, Mars: Implications for Near Surface Stratigraphy, Surface Processes, and Erosion Rates

Author

Maria Elaine Banks, N H Warner, J A Grant, S A Wilson, Matthew P Golombek, A DeMott, C Charalambous, E Hauber, V Ansan, C Weitz, T Pike, N Williams, M E Banks, F Calef, M Baker, M Kopp, M Deahn, H Lethcoe, and L Berger

Subjects
Earth Resources And Remote Sensing
Abstract

The InSight mission to Mars landed within Homestead hollow on an Early Amazonian lavaplain. The hollow is a 27‐m‐diameter, 0.3‐m‐deep quasi‐circular depression that shares morphologic and sedimentologic characteristics to degraded impact craters. Unlike the intercrater plains outside of the hollow, the interior lacks cobbles and is dominated by loose sand, granules, and pebbles. Fresher craters near the landing site exhibit meter‐scale bedforms in their ejecta and on their floors due to sediment trapping.The sedimentology of the interior fill of Homestead hollow suggests similar trapping. The hollow falls along amorphologic continuum that requires low rates of rim degradation and fill. Crater degradation rates (rim erosion plus filling) in the landing site decline nonlinearly through time from 10−2to 10−4m/Myr as craters evolve to a hollow‐like form. Rim erosion rates are lower initially, at 10−3m/Myr, but converge with degradation rates to 10−4m/Myr. This implies that while filling plays an important role soon after crater formation, it is limited in later stages. Crater statistics indicate that the bulk of the fill occurred in the first~50 Myr for Homestead hollow. The estimated maximum age of the hollow is ~400 to 700 Myr. This requires near‐zero fill aggradation and long‐term soil stability for the bulk of the crater's history. Fill stability manifests in Homestead hollow as a ~5‐to 10‐cm‐thick duricrust, formed by exchanges of atmospheric water vapor with soil. The estimated degradation in the hollow requires ~2 to 3 m of sedimentary fill beneath the lander.

Published
2020
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5. Samples Collected from the Floor of Jezero Crater with the Mars 2020 Perseverance Rover

Author

J. I. Simon, K. Hickman‐Lewis, B. A. Cohen, L.E. Mayhew, D.L. Shuster, V. Debaille, E. M. Hausrath, B.P. Weiss, T. Bosak, M.‐P. Zorzano, H. E. F. Amundsen, L.W. Beegle, J.F. Bell, K. C. Benison, E. L. Berger, O. Beyssac, A.J. Brown, F. Calef, T. M. Casademont, B. Clark, E. Clavé, L. Crumpler, A. D. Czaja, A. G. Fairén, K. A. Farley, D. T. Flannery, T. Fornaro, O. Forni, F. Gómez, Y. Goreva, A. Gorin, K. P. Hand, S.‐E. Hamran, J. Henneke, C. D. K. Herd, B. H. N. Horgan, J. R. Johnson, J. Joseph, R. E. Kronyak, J. M. Madariaga, J. N. Maki, L. Mandon, F. M. McCubbin, S. M. McLennan, R. C. Moeller, C. E. Newman, J. I. Núñez, A. C. Pascuzzo, D. A. Pedersen, G. Poggiali, P. Pinet, C. Quantin‐Nataf, M. Rice, J. W. Rice, C. Royer, M. Schmidt, M. Sephton, S. Sharma, S. Siljeström, K. M. Stack, A. Steele, V. Z. Sun, A. Udry, S. VanBommel, M. Wadhwa, R. C. Wiens, A. J. Williams, and K. H. Williford

Subjects
Mars Sample Return, rock core, Geophysics, Space and Planetary Science, Geochemistry and Petrology, Jezero Crater, Mars 2020, Earth and Planetary Sciences (miscellaneous)
Abstract

The first samples collected by the Mars 2020 mission represent units exposed on the Jezero Crater floor, from the potentially oldest Séítah formation outcrops to the potentially youngest rocks of the heavily cratered Máaz formation. Surface investigations reveal landscape-to-microscopic textural, mineralogical, and geochemical evidence for igneous lithologies, some possibly emplaced as lava flows. The samples contain major rock-forming minerals such as pyroxene, olivine, and feldspar, accessory minerals including oxides and phosphates, and evidence for various degrees of aqueous activity in the form of water-soluble salt, carbonate, sulfate, iron oxide, and iron silicate minerals. Following sample return, the compositions and ages of these variably altered igneous rocks are expected to reveal the geophysical and geochemical nature of the planet’s interior at the time of emplacement, characterize martian magmatism, and place timing constraints on geologic processes, both in Jezero Crater and more widely on Mars. Petrographic observations and geochemical analyses, coupled with geochronology of secondary minerals, can also reveal the timing of aqueous activity as well as constrain the chemical and physical conditions of the environments in which these minerals precipitated, and the nature and composition of organic compounds preserved in association with these phases. Returned samples from these units will help constrain the crater chronology of Mars and the global evolution of the planet’s interior, for understanding the processes that formed Jezero Crater floor units, and for constraining the style and duration of aqueous activity in Jezero Crater, past habitability, and cycling of organic elements in Jezero Crater.

Published
2023
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6. Chemical variations in Yellowknife Bay formation sedimentary rocks analyzed by ChemCam on board the Curiosity rover on Mars

Author

N. Mangold, O. Forni, G. Dromart, K. Stack, R. C. Wiens, O. Gasnault, D. Y. Sumner, M. Nachon, P.‐Y. Meslin, R. B. Anderson, B. Barraclough, J. F. Bell, G. Berger, D. L. Blaney, J. C. Bridges, F. Calef, B. Clark, S. M. Clegg, A. Cousin, L. Edgar, K. Edgett, B. Ehlmann, C. Fabre, M. Fisk, J. Grotzinger, S. Gupta, K. E. Herkenhoff, J. Hurowitz, J. R. Johnson, L. C. Kah, N. Lanza, J. Lasue, S. Le Mouélic, R. Léveillé, E. Lewin, M. Malin, S. McLennan, S. Maurice, N. Melikechi, A. Mezzacappa, R. Milliken, H. Newsom, A. Ollila, S. K. Rowland, V. Sautter, M. Schmidt, S. Schröder, C. d'Uston, D. Vaniman, and R. Williams

Published
2015
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7. A Komatiite Succession as an analog for the Olivine Bearing Rocks at Jezero

Author

A., Brown, R.C., Wiens, S., Maurice, K., Uckert, M., Tice, D. Flannery R.G., Deen, A.H., Treiman, K. L., Siebach, L.W., Beegle, W.J., Abbey, J.F., Bell, L.E., Mayhew, J.I., Simon, O., Beyssac, P.A., Willis, R., Bhartia, R.J., Smith, T., Fouchet, C., Quantin-Nataf., Pinet, P.C., L., Mandon, S. Le, Mouélic, A., Udry, B., Horgan, F., Calef, E., Cloutis, N., Turenne, C., Royer, M.-P., Zorzano, E., Ravanis, S., Fagents, A., Fairen, S., Gupta, V., Sautter, Y., Liu, M., Schmidt, K., Hickman-Lewis, Tennessee State University, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Jackson School of Geosciences (JSG), University of Texas at Austin [Austin], Rice University [Houston], NASA Johnson Space Center (JSC), NASA, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Cornell University [New York], Imperial College London, Brock University [Canada], The Natural History Museum [London] (NHM), and pinet, patrick

Subjects
[SDU] Sciences of the Universe [physics], [SDU]Sciences of the Universe [physics], [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, planetary surface, mars, mineralogy, petrology
Abstract

International audience

Published
2022

8. A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars

Author

J. P. Grotzinger, D. Y. Sumner, L. C. Kah, K. Stack, S. Gupta, L. Edgar, D. Rubin, K. Lewis, J. Schieber, N. Mangold, R. Milliken, P. G. Conrad, D. DesMarais, J. Farmer, K. Siebach, F. Calef, J. Hurowitz, S. M. McLennan, D. Ming, D. Vaniman, J. Crisp, A. Vasavada, K. S. Edgett, M. Malin, D. Blake, R. Gellert, P. Mahaffy, R. C. Wiens, S. Maurice, J. A. Grant, S. Wilson, R. C. Anderson, L. Beegle, R. Arvidson, B. Hallet, R. S. Sletten, M. Rice, J. Bell, J. Griffes, B. Ehlmann, R. B. Anderson, T. F. Bristow, W. E. Dietrich, G. Dromart, J. Eigenbrode, A. Fraeman, C. Hardgrove, K. Herkenhoff, L. Jandura, G. Kocurek, S. Lee, L. A. Leshin, R. Leveille, D. Limonadi, J. Maki, S. McCloskey, M. Meyer, M. Minitti, H. Newsom, D. Oehler, A. Okon, M. Palucis, T. Parker, S. Rowland, M. Schmidt, S. Squyres, A. Steele, E. Stolper, R. Summons, A. Treiman, R. Williams, A. Yingst, MSL Science Team, Osku Kemppinen, Nathan Bridges, Jeffrey R. Johnson, David Cremers, Austin Godber, Meenakshi Wadhwa, Danika Wellington, Ian McEwan, Claire Newman, Mark Richardson, Antoine Charpentier, Laurent Peret, Penelope King, Jennifer Blank, Gerald Weigle, Shuai Li, Kevin Robertson, Vivian Sun, Michael Baker, Christopher Edwards, Kenneth Farley, Hayden Miller, Megan Newcombe, Cedric Pilorget, Claude Brunet, Victoria Hipkin, Richard Léveillé, Geneviève Marchand, Pablo Sobrón Sánchez, Laurent Favot, George Cody, Lorenzo Flückiger, David Lees, Ara Nefian, Mildred Martin, Marc Gailhanou, Frances Westall, Guy Israël, Christophe Agard, Julien Baroukh, Christophe Donny, Alain Gaboriaud, Philippe Guillemot, Vivian Lafaille, Eric Lorigny, Alexis Paillet, René Pérez, Muriel Saccoccio, Charles Yana, Carlos Armiens-Aparicio, Javier Caride Rodríguez, Isaías Carrasco Blázquez, Felipe Gómez Gómez, Javier Gómez-Elvira, Sebastian Hettrich, Alain Lepinette Malvitte, Mercedes Marín Jiménez, Jesús Martínez-Frías, Javier Martín-Soler, F. Javier Martín-Torres, Antonio Molina Jurado, Luis Mora-Sotomayor, Guillermo Muñoz Caro, Sara Navarro López, Verónica Peinado-González, Jorge Pla-García, José Antonio Rodriguez Manfredi, Julio José Romeral-Planelló, Sara Alejandra Sans Fuentes, Eduardo Sebastian Martinez, Josefina Torres Redondo, Roser Urqui-O’Callaghan, María-Paz Zorzano Mier, Steve Chipera, Jean-Luc Lacour, Patrick Mauchien, Jean-Baptiste Sirven, Heidi Manning, Alberto Fairén, Alexander Hayes, Jonathan Joseph, Robert Sullivan, Peter Thomas, Audrey Dupont, Angela Lundberg, Noureddine Melikechi, Alissa Mezzacappa, Julia DeMarines, David Grinspoon, Günther Reitz, Benito Prats, Evgeny Atlaskin, Maria Genzer, Ari-Matti Harri, Harri Haukka, Henrik Kahanpää, Janne Kauhanen, Mark Paton, Jouni Polkko, Walter Schmidt, Tero Siili, Cécile Fabre, James Wray, Mary Beth Wilhelm, Franck Poitrasson, Kiran Patel, Stephen Gorevan, Stephen Indyk, Gale Paulsen, David Bish, Brigitte Gondet, Yves Langevin, Claude Geffroy, David Baratoux, Gilles Berger, Alain Cros, Claude d’Uston, Olivier Forni, Olivier Gasnault, Jérémie Lasue, Qiu-Mei Lee, Pierre-Yves Meslin, Etienne Pallier, Yann Parot, Patrick Pinet, Susanne Schröder, Mike Toplis, Éric Lewin, Will Brunner, Ezat Heydari, Cherie Achilles, Brad Sutter, Michel Cabane, David Coscia, Cyril Szopa, François Robert, Violaine Sautter, Stéphane Le Mouélic, Marion Nachon, Arnaud Buch, Fabien Stalport, Patrice Coll, Pascaline François, François Raulin, Samuel Teinturier, James Cameron, Sam Clegg, Agnès Cousin, Dorothea DeLapp, Robert Dingler, Ryan Steele Jackson, Stephen Johnstone, Nina Lanza, Cynthia Little, Tony Nelson, Richard B. Williams, Andrea Jones, Laurel Kirkland, Burt Baker, Bruce Cantor, Michael Caplinger, Scott Davis, Brian Duston, Donald Fay, David Harker, Paul Herrera, Elsa Jensen, Megan R. Kennedy, Gillian Krezoski, Daniel Krysak, Leslie Lipkaman, Elaina McCartney, Sean McNair, Brian Nixon, Liliya Posiolova, Michael Ravine, Andrew Salamon, Lee Saper, Kevin Stoiber, Kimberley Supulver, Jason Van Beek, Tessa Van Beek, Robert Zimdar, Katherine Louise French, Karl Iagnemma, Kristen Miller, Fred Goesmann, Walter Goetz, Stubbe Hviid, Micah Johnson, Matthew Lefavor, Eric Lyness, Elly Breves, M. Darby Dyar, Caleb Fassett, Laurence Edwards, Robert Haberle, Tori Hoehler, Jeff Hollingsworth, Melinda Kahre, Leslie Keely, Christopher McKay, Lora Bleacher, William Brinckerhoff, David Choi, Jason P. Dworkin, Melissa Floyd, Caroline Freissinet, James Garvin, Daniel Glavin, Daniel Harpold, David K. Martin, Amy McAdam, Alexander Pavlov, Eric Raaen, Michael D. Smith, Jennifer Stern, Florence Tan, Melissa Trainer, Arik Posner, Mary Voytek, Andrew Aubrey, Alberto Behar, Diana Blaney, David Brinza, Lance Christensen, Lauren DeFlores, Jason Feldman, Sabrina Feldman, Gregory Flesch, Insoo Jun, Didier Keymeulen, Michael Mischna, John Michael Morookian, Betina Pavri, Marcel Schoppers, Aaron Sengstacken, John J. Simmonds, Nicole Spanovich, Manuel de la Torre Juarez, Christopher R. Webster, Albert Yen, Paul Douglas Archer, Francis Cucinotta, John H. Jones, Richard V. Morris, Paul Niles, Elizabeth Rampe, Thomas Nolan, Martin Fisk, Leon Radziemski, Bruce Barraclough, Steve Bender, Daniel Berman, Eldar Noe Dobrea, Robert Tokar, Timothy Cleghorn, Wesley Huntress, Gérard Manhès, Judy Hudgins, Timothy Olson, Noel Stewart, Philippe Sarrazin, Edward Vicenzi, Mark Bullock, Bent Ehresmann, Victoria Hamilton, Donald Hassler, Joseph Peterson, Scot Rafkin, Cary Zeitlin, Fedor Fedosov, Dmitry Golovin, Natalya Karpushkina, Alexander Kozyrev, Maxim Litvak, Alexey Malakhov, Igor Mitrofanov, Maxim Mokrousov, Sergey Nikiforov, Vasily Prokhorov, Anton Sanin, Vladislav Tretyakov, Alexey Varenikov, Andrey Vostrukhin, Ruslan Kuzmin, Benton Clark, Michael Wolff, Oliver Botta, Darrell Drake, Keri Bean, Mark Lemmon, Susanne P. Schwenzer, Ella Mae Lee, Robert Sucharski, Miguel Ángel de Pablo Hernández, Juan José Blanco Ávalos, Miguel Ramos, Myung-Hee Kim, Charles Malespin, Ianik Plante, Jan-Peter Muller, Rafael Navarro-González, Ryan Ewing, William Boynton, Robert Downs, Mike Fitzgibbon, Karl Harshman, Shaunna Morrison, Onno Kortmann, Amy Williams, Günter Lugmair, Michael A. Wilson, Bruce Jakosky, Tonci Balic-Zunic, Jens Frydenvang, Jaqueline Kløvgaard Jensen, Kjartan Kinch, Asmus Koefoed, Morten Bo Madsen, Susan Louise Svane Stipp, Nick Boyd, John L. Campbell, Glynis Perrett, Irina Pradler, Scott VanBommel, Samantha Jacob, Tobias Owen, Hannu Savijärvi, Eckart Boehm, Stephan Böttcher, Sönke Burmeister, Jingnan Guo, Jan Köhler, César Martín García, Reinhold Mueller-Mellin, Robert Wimmer-Schweingruber, John C. Bridges, Timothy McConnochie, Mehdi Benna, Heather Franz, Hannah Bower, Anna Brunner, Hannah Blau, Thomas Boucher, Marco Carmosino, Sushil Atreya, Harvey Elliott, Douglas Halleaux, Nilton Rennó, Michael Wong, Robert Pepin, Beverley Elliott, John Spray, Lucy Thompson, Suzanne Gordon, Ann Ollila, Joshua Williams, Paulo Vasconcelos, Jennifer Bentz, Kenneth Nealson, Radu Popa, Jeffrey Moersch, Christopher Tate, Mackenzie Day, Raymond Francis, Emily McCullough, Ed Cloutis, Inge Loes ten Kate, Daniel Scholes, Susan Slavney, Thomas Stein, Jennifer Ward, Jeffrey Berger, John E. Moores, Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Department of Earth and Planetary Science [UC Berkeley] (EPS), University of California [Berkeley], University of California-University of California, The University of Tennessee [Knoxville], Department of Earth Science and Technology [Imperial College London], Imperial College London, ASU School of Earth and Space Exploration (SESE), Arizona State University [Tempe] (ASU), US Geological Survey [Santa Cruz], United States Geological Survey [Reston] (USGS), Princeton University, Department of Geological Sciences [Bloomington], Indiana University [Bloomington], Indiana University System-Indiana University System, Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Geological Sciences [Providence], Brown University, NASA Goddard Space Flight Center (GSFC), NASA Ames Research Center (ARC), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Geosciences [Stony Brook], Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), State University of New York (SUNY), NASA Johnson Space Center (JSC), NASA, Planetary Science Institute [Tucson] (PSI), Department of Physics [Guelph], University of Guelph, Space Remote Sensing Group (ISR-2), Los Alamos National Laboratory (LANL), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Center for Earth and Planetary Studies [Washington] (CEPS), Smithsonian National Air and Space Museum, Smithsonian Institution-Smithsonian Institution, Department of Earth and Space Sciences [Seattle], University of Washington [Seattle], Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Department of Geological Sciences [Austin], Jackson School of Geosciences (JSG), University of Texas at Austin [Austin]-University of Texas at Austin [Austin], Rensselaer Polytechnic Institute (RPI), Canadian Space Agency (CSA), NASA Headquarters, Institute of Meteoritics [Albuquerque] (IOM), The University of New Mexico [Albuquerque], University of Hawaii, Brock University [Canada], Cornell University [New York], Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science [Washington], Massachusetts Institute of Technology (MIT), Lunar and Planetary Institute [Houston] (LPI), GeoRessources, Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Institut national des sciences de l'Univers (INSU - CNRS), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Carnegie Institution for Science, Institut national des sciences de l'Univers (INSU - CNRS)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), NWO-NSO: The role of perchlorates in the preservation of organic compounds on Mars, and Petrology

Subjects
Geologic Sediments, Salinity, Extraterrestrial Environment, Nitrogen, General Science & Technology, Iron, Curiosity rover, Mars, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Astrobiology, MSL Science Team, Exobiology, MSL, Martian, Multidisciplinary, fluvial-lacustrine environments, Biosphere, Water, Phosphorus, Mars Exploration Program, 15. Life on land, Hydrogen-Ion Concentration, Carbon, Oxygen, Planetary science, Bays, 13. Climate action, Rocknest, Sample Analysis at Mars, Sedimentary rock, Oxidation-Reduction, Geology, Sulfur, Hydrogen
Abstract

International audience; The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both iron and sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, and phosphorus were measured directly as key biogenic elements; by inference, phosphorus is assumed to have been available. The environment probably had a minimum duration of hundreds to tens of thousands of years. These results highlight the biological viability of fluvial-lacustrine environments in the post-Noachian history of Mars.

Published
2014
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9. Mesochem: Chemical Dynamics on a Mesoscopic Scale

Author

L E Fried, R H Gee, C J Wu, and D F Calef

Subjects
chemistry.chemical_classification, Mesoscopic physics, Materials science, Explosive material, Scale (ratio), Crystallization of polymers, Nanotechnology, Polymer, Chemical Dynamics, law.invention, chemistry, law, Particle size, Crystallization
Abstract

Most chemically stable organic materials age through changes on the mesoscopic scale (from 10 nm to 10 mm). Examples include the slow crystallization of polymers, changes in particle size distributions with age, and the swelling of pressed powders. We began the Mesochem project to develop a new mesoscopic modeling capability for organic materials, including polymers, molecular crystals, and filled polymer composites. Our goal was to develop and validate novel mesoscopic modeling techniques that are well suited for materials of interest to LLNL's nation security mission, such as high explosives, binding agents, and foams.

Published
2004
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10. The Reaction Kinetics of LiD with Water Vapor

Author

M Balooch, D F Calef, and L N Dinh

Subjects
Chemical kinetics, Auger electron spectroscopy, Hydrogen, chemistry, Scanning electron microscope, Diffusion, Analytical chemistry, chemistry.chemical_element, Activation energy, Partial pressure, Water vapor
Abstract

The interaction of LiD with water vapor in the partial pressure range of 10{sup -7} Torr to 20 Torr has been investigated. The reaction probability of water with pure LiD cleaved in an ultra high vacuum environment was obtained using the modulated molecular beam technique. This probability was 0.11 and independent of LiD surface temperature suggesting a negligible activation energy for the reaction in agreement with quantum chemical calculations. The value gradually reduced, however, to .007 as the surface concentration of oxygen containing product (LiOH), which was monitored in-situ by Auger electron spectroscopy on the reaction zone, approached full coverage. As the hydroxide film grew beyond a monolayer, the phase lag of hydrogen product increased from zero to 20 degrees and the reaction probability reduced further until it approached our detection limit ({approx} 10{sup -4}). This phase lag was attributed to a diffusion limited process in this regime. In separate experiments, the film growth has been studied in nitrogen atmosphere with 100% relative humidity using thermogravimetric analysis (TGA) and in air with 50% relative humidity utilizing scanning electron microscopy (SEM). For exposures to environment with high water concentrations and for micrometer thick films, the reaction probability reduced to 4 xmore » 10{sup -7} and was independent of exposure time, The lattice diffusion through the film was no longer controlling the transport of water to the LiD/LiOH interface. Microcracks generated in the film to release stress provided easier pathways to the interface. A modified microscope, capable of both atomic force microscopy (AFM) and nanoindentation, was employed to investigate the surface morphology of LiOH.H{sub 2}O grown on LiOH at high water vapor partial pressures and the kinetics of this growth.« less

Published
2003
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11. Diffusion-Controlled Reactions

Author

and D F Calef and John M. Deutch

Subjects
Reaction rate, chemistry.chemical_classification, Colloid, Chemistry, Diffusion, Thermodynamics, Crystal growth, Polymer, Physical and Theoretical Chemistry, Heterogeneous catalysis, Catalysis, Biophysical chemistry
Abstract

It is apparent that the kinetic rate kD influences the effective rate of reaction and that in certain circumstances (kr � kr) it becomes the rate­ limiting step [keff = kD]. Accordingly, the rate coefficient kD' which describes the mass transport rate at which reactants encounter each other, is of central concern to solution kineticists. There is little doubt that the subject of diffusion-controlled reactions has broad application beyond this prototype example. Diffusion-controlled reactions play a prominent role in heterogeneous catalysis (after all, the perfeot catalyst leads to mass transport limitations), polymer chain growth kinetics, colloid or crystal growth, and biophysical chemistry.

Published
1983
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12. Diffusion in lipid bilayers containing barriers

Author

A. A. Rigos, Daniel F. Calef, and John M. Deutch

Subjects
Diffusion equation, Chemistry, Membrane lipids, Bilayer, Lipid Bilayers, Analytical chemistry, Biophysics, Biological membrane, Models, Biological, Epithelium, Diffusion, Membrane Lipids, Membrane, Chemical physics, Monolayer, Animals, lipids (amino acids, peptides, and proteins), Diffusion (business), Lipid bilayer, Mathematics, Research Article
Abstract

In epithelial cells, a barrier or tight junction restricts the diffusion of lipid probes from the apical to the basolateral side of the outer membrane bilayer. This phenomenon is studied theoretically with the diffusion equation on planar and spherical surfaces. Two models for the tight junction are considered: a penetrable barrier embedded in a monolayer and an impenetrable obstacle in the outer membrane of a bilayer than must be bypassed by flip-flopping between inner and outer membranes. The rate of passing from one side of the cell to the other is calculated for each of these models under steady state conditions. The results are compared with recent fluorescent photobleaching recovery experiments. The theoretical interpretation indicates that it would be difficult to distinguish experimentally between the flip-flop case and the barrier crossing case. Assuming a flip-flop model, large differences in the magnitude of the flip-flop rates of probes are necessary to explain the experimental results as suggested by Dragsten et al. (Dragsten, P. R., R. Blumenthal, and J. S. Handler, 1981, Nature [Lond.], 294:718--722).

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13. Calculation of the Green's function from high- and low-density series expansions for disordered transport

Author

Brian B. Laird, Gregory Korzeniewski, Richard A. Friesner, Daniel F. Calef, and Robert J. Silbey

Subjects
Random graph, Combinatorics, Physics, symbols.namesake, Laplace transform, Green's function, Master equation, Cluster (physics), symbols, Thermodynamics, Function (mathematics), Series expansion, Random variable
Abstract

connected nwlusters ' [u1 —W,i] connected decompositions [u1 —W,s] The problem of transport of a localized particle in a random network has been the subject of many investigations, ' ' which have been applicable either to very long or very short times. In this paper, we present a new calculation which bridges the gap between short and long times, by using both lowand high-density expansions in a novel two-point Pade approximant technique. " As an example, we compute the probability of remaining on the initial site, Po(r), as a function of time for a two-dimensional triangular lattice. Using scaling arguments based on the recent results of Coniglio for the structure of the percolating cluster, we examine both the critical and noncritical parts of Po(r) near the percolation edge, and finally we address the question of anomalous diffusion on this cluster. ' The model we consider is a triangular lattice with randomly populated sites, on which the transport is governed by a master equation with transfer matrix 8', whose elements W&= tv(g&. Here, w is the nonrandom nearest-neighbor jump rate and g, is a random variable for occupation of site i: (& = 0 if i is unoccupied, (;= 1 if it is occupied, and (g, ) = p (the concentration of occupied sites), where the bracket represents an average over all configurations consistent with p. The probability of occupation of a site at time t is governed by the averaged Green's function, G(t) = (exp Wr), or by its Laplace transform, G(u) = ([ul —W] '). The probability that the particle is at the initial site is given by Gas(t), which is, of course, a function of p. We write the low-density expansion of G (u ) as The first term on the right-hand side of Eq. (2) corresponds to solving the master equation on a given cluster of n sites; the second term removes from this all processes involving fewer than n sites, leaving only processes contributing to p". All possible locations of the n cluster are summed over in Eq. (2). To compute Gpp( ),uwe only consider connected clusters containing the origin and sum over all locations by taking the trace for each unique cluster. We enumerate the clusters and perform the matrix inversions on a computer. In the same spirit, we write the high-density expansion as

Published
1984
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15. The role of polymer matrix structure and interparticle interactions in diffusion-limited drug release

Author

Daniel F. Calef, Robert Langer, John M. Deutch, Ronald A. Siegel, and Anna C. Balazs

Subjects
Polymers, Biophysics, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Diffusion, Physical Phenomena, Physical phenomena, Lattice (order), Porosity, chemistry.chemical_classification, Physics, Particle interaction, Polymer, Models, Theoretical, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, Chemical physics, Delayed-Action Preparations, Drug release, 0210 nano-technology, Order of magnitude, Communication channel, Research Article
Abstract

A lattice random-walk model is used to simulate diffusion in a porous polymer. This model may be useful for the practical design of drug-release systems. Both interacting and noninteracting particles (random walkers) were allowed to diffuse through a pore with a single exit hole. It was found that the specific interactions among the diffusing particles have little influence on the overall release rate. Diffusion through more complicated structures was investigated by simulating the diffusion of particles through two pores connected by a constricted channel whose length and width were varied. The overall rate of release was found to be proportional to the width of the constricted channel. When the length of the channel was greater than or equal to the length of the pore, the rate of release was also inversely proportional to the channel length. From a practical standpoint, release rates can be decreased (and times for release increased) by one or two orders of magnitude by decreasing the width and expanding the length of the interconnecting channels in the polymer matrix.

Published
1985

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