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Lemmon MT, Lorenz RD, Rabinovitch J, Newman CE, Williams NR, Sullivan R, Golombek MP, Bell JF, Maki JN, Vicente‐Retortillo A. Lifting and Transport of Martian Dust by the Ingenuity Helicopter Rotor Downwash as Observed by High-Speed Imaging From the Perseverance Rover. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2022; 127:e2022JE007605. [PMID: 37033154 PMCID: PMC10078181 DOI: 10.1029/2022je007605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/19/2022] [Accepted: 11/29/2022] [Indexed: 06/19/2023]
Abstract
Martian atmospheric dust is a major driver of weather, with feedback between atmospheric dust distribution, circulation changes from radiative heating and cooling driven by this dust, and winds that mobilize surface dust and distribute it in the atmosphere. Wind-driven mobilization of surface dust is a poorly understood process due to significant uncertainty about minimum wind stress and whether the saltation of sand particles is required. This study utilizes video of six Ingenuity helicopter flights to measure dust lifting during helicopter ascents, traverses, and descents. Dust mobilization persisted on takeoff until the helicopter exceeded 3 m altitude, with dust advecting at 4-6 m/s. During landing, dust mobilization initiated at 2.3-3.6 m altitude. Extensive dust mobilization occurred during traverses at 5.1-5.7 m altitude. Dust mobilization threshold friction velocity of rotor-induced winds during landing is modeled at 0.4-0.6 m/s (factor of two uncertainty in this estimate), with higher winds required when the helicopter was over undisturbed terrain. Modeling dust mobilization from >5 m cruising altitude indicates mobilization by 0.3 m/s winds, suggesting nonsaltation mechanisms such as mobilization and destruction of dust aggregates. No dependence on background winds was seen for the initiation of dust lifting but one case of takeoff in 7 m/s winds created a track of darkened terrain downwind of the helicopter, which may have been a saltation cluster. When the helicopter was cruising at 5-6 m altitude, recirculation was seen in the dust clouds.
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Affiliation(s)
| | | | | | | | - N. R. Williams
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - M. P. Golombek
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - J. N. Maki
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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2
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Bell JF, Maki JN, Alwmark S, Ehlmann BL, Fagents SA, Grotzinger JP, Gupta S, Hayes A, Herkenhoff KE, Horgan BHN, Johnson JR, Kinch KB, Lemmon MT, Madsen MB, Núñez JI, Paar G, Rice M, Rice JW, Schmitz N, Sullivan R, Vaughan A, Wolff MJ, Bechtold A, Bosak T, Duflot LE, Fairén AG, Garczynski B, Jaumann R, Merusi M, Million C, Ravanis E, Shuster DL, Simon J, St. Clair M, Tate C, Walter S, Weiss B, Bailey AM, Bertrand T, Beyssac O, Brown AJ, Caballo-Perucha P, Caplinger MA, Caudill CM, Cary F, Cisneros E, Cloutis EA, Cluff N, Corlies P, Crawford K, Curtis S, Deen R, Dixon D, Donaldson C, Barrington M, Ficht M, Fleron S, Hansen M, Harker D, Howson R, Huggett J, Jacob S, Jensen E, Jensen OB, Jodhpurkar M, Joseph J, Juarez C, Kah LC, Kanine O, Kristensen J, Kubacki T, Lapo K, Magee A, Maimone M, Mehall GL, Mehall L, Mollerup J, Viúdez-Moreiras D, Paris K, Powell KE, Preusker F, Proton J, Rojas C, Sallurday D, Saxton K, Scheller E, Seeger CH, Starr M, Stein N, Turenne N, Van Beek J, Winhold AG, Yingling R. Geological, multispectral, and meteorological imaging results from the Mars 2020 Perseverance rover in Jezero crater. SCIENCE ADVANCES 2022; 8:eabo4856. [PMID: 36417517 PMCID: PMC9683734 DOI: 10.1126/sciadv.abo4856] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 10/20/2022] [Indexed: 06/15/2023]
Abstract
Perseverance's Mastcam-Z instrument provides high-resolution stereo and multispectral images with a unique combination of spatial resolution, spatial coverage, and wavelength coverage along the rover's traverse in Jezero crater, Mars. Images reveal rocks consistent with an igneous (including volcanic and/or volcaniclastic) and/or impactite origin and limited aqueous alteration, including polygonally fractured rocks with weathered coatings; massive boulder-forming bedrock consisting of mafic silicates, ferric oxides, and/or iron-bearing alteration minerals; and coarsely layered outcrops dominated by olivine. Pyroxene dominates the iron-bearing mineralogy in the fine-grained regolith, while olivine dominates the coarse-grained regolith. Solar and atmospheric imaging observations show significant intra- and intersol variations in dust optical depth and water ice clouds, as well as unique examples of boundary layer vortex action from both natural (dust devil) and Ingenuity helicopter-induced dust lifting. High-resolution stereo imaging also provides geologic context for rover operations, other instrument observations, and sample selection, characterization, and confirmation.
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Affiliation(s)
- James F. Bell
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Justin N. Maki
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Sanna Alwmark
- Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
- Department of Geology, Lund University, 22362 Lund, Sweden
| | - Bethany L. Ehlmann
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Sarah A. Fagents
- Hawai’i Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822, USA
| | | | - Sanjeev Gupta
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Alexander Hayes
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | | | - Briony H. N. Horgan
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Jeffrey R. Johnson
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - Kjartan B. Kinch
- Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | | | - Morten B. Madsen
- Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Jorge I. Núñez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - Melissa Rice
- Western Washington University, Bellingham, WA 98225, USA
| | - James W. Rice
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | | | - Robert Sullivan
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | - Alicia Vaughan
- USGS Astrogeology Science Center, Flagstaff, AZ 86001, USA
| | | | - Andreas Bechtold
- Department of Lithospheric Research, University of Vienna, 1090 Vienna, Austria
- Austrian Academy of Sciences, Vienna 1010, Austria
| | - Tanja Bosak
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | - Alberto G. Fairén
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
- Astrobiology Center (CSIC-INTA), Madrid, Spain
| | - Brad Garczynski
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Ralf Jaumann
- Institute for Geological Sciences, Freie Universitaet Berlin, 14195 Berlin, Germany
| | - Marco Merusi
- Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | | | - Eleni Ravanis
- Hawai’i Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822, USA
| | - David L. Shuster
- Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Justin Simon
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | | | - Christian Tate
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | - Sebastian Walter
- Institute for Geological Sciences, Freie Universitaet Berlin, 14195 Berlin, Germany
| | - Benjamin Weiss
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alyssa M. Bailey
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | | | - Olivier Beyssac
- Institut de Minéralogie, Physique des Matériaux et Cosmochimie, CNRS, Muséum National d’Histoire Naturelle, Sorbonne University, Paris 75005, France
| | | | | | | | | | - Francesca Cary
- Hawai’i Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822, USA
| | - Ernest Cisneros
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | | | - Nathan Cluff
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Paul Corlies
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | - Kelsie Crawford
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Sabrina Curtis
- Western Washington University, Bellingham, WA 98225, USA
| | - Robert Deen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Darian Dixon
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | | | - Megan Barrington
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | - Michelle Ficht
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | | | | | - David Harker
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Rachel Howson
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Joshua Huggett
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Samantha Jacob
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Elsa Jensen
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Ole B. Jensen
- Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Mohini Jodhpurkar
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Jonathan Joseph
- Department of Astronomy, Cornell University, Ithaca, NY 14850, USA
| | | | - Linda C. Kah
- Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37916, USA
| | - Oak Kanine
- California Institute of Technology, Pasadena, CA 91125, USA
| | | | - Tex Kubacki
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Kristiana Lapo
- Western Washington University, Bellingham, WA 98225, USA
| | - Angela Magee
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | | | - Greg L. Mehall
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Laura Mehall
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Jess Mollerup
- Western Washington University, Bellingham, WA 98225, USA
| | - Daniel Viúdez-Moreiras
- Astrobiology Center (CSIC-INTA), Madrid, Spain
- National Institute for Aerospace Technology, Madrid, Spain
| | - Kristen Paris
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | - Kathryn E. Powell
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | | | | | - Corrine Rojas
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
| | | | - Kim Saxton
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Eva Scheller
- California Institute of Technology, Pasadena, CA 91125, USA
| | | | - Mason Starr
- Malin Space Science Systems Inc., San Diego, CA 92121, USA
| | - Nathan Stein
- California Institute of Technology, Pasadena, CA 91125, USA
| | | | - Jason Van Beek
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - Andrew G. Winhold
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85281, USA
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3
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Love R, Jackson DWT, Michaels T, Smyth TAG, Avouac JP, Cooper A. From Macro- to Microscale: A combined modelling approach for near-surface wind flow on Mars at sub-dune length-scales. PLoS One 2022; 17:e0276547. [PMCID: PMC9635718 DOI: 10.1371/journal.pone.0276547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
Abstract
The processes that initiate and sustain sediment transport which contribute to the modification of aeolian deposits in Mars’ low-density atmosphere are still not fully understood despite recent atmospheric modelling. However, detailed microscale wind flow modelling, using Computational Fluid Dynamics at a resolution of <2 m, provides insights into the near-surface processes that cannot be modeled using larger-scale atmospheric modeling. Such Computational Fluid Dynamics simulations cannot by themselves account for regional-scale atmospheric circulations or flow modifications induced by regional km-scale topography, although realistic fine-scale mesoscale atmospheric modeling can. Using the output parameters from mesoscale simulations to inform the input conditions for the Computational Fluid Dynamics microscale simulations provides a practical approach to simulate near-surface wind flow and its relationship to very small-scale topographic features on Mars, particularly in areas which lack in situ rover data. This paper sets out a series of integrated techniques to enable a multi-scale modelling approach for surface airflow to derive surface airflow dynamics at a (dune) landform scale using High Resolution Imaging Science Experiment derived topographic data. The work therefore provides a more informed and realistic Computational Fluid Dynamics microscale modelling method, which will provide more detailed insight into the surface wind forcing of aeolian transport patterns on martian surfaces such as dunes.
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Affiliation(s)
- Richard Love
- School of Geography & Environmental Sciences, Ulster University, Northern Ireland, United Kingdom
- * E-mail:
| | - Derek W. T. Jackson
- School of Geography & Environmental Sciences, Ulster University, Northern Ireland, United Kingdom
- Geological Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Timothy Michaels
- Carl Sagan Center (at the SETI Institute), Mountain View, California, United States of America
| | - Thomas A. G. Smyth
- Department of Biological and Geographical Sciences, School of Applied Sciences, University of Huddersfield, England, United Kingdom
| | - Jean-Philippe Avouac
- School of Geography & Environmental Sciences, Ulster University, Northern Ireland, United Kingdom
- Division of Geological and Planetary Sciences, CalTech, Pasadena, California, United States of America
| | - Andrew Cooper
- School of Geography & Environmental Sciences, Ulster University, Northern Ireland, United Kingdom
- Geological Sciences, University of KwaZulu-Natal, Durban, South Africa
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4
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Stack KM, Dietrich WE, Lamb MP, Sullivan RJ, Christian JR, Newman CE, O’Connell‐Cooper CD, Sneed JW, Day M, Baker M, Arvidson RE, Fedo CM, Khan S, Williams RME, Bennett KA, Bryk AB, Cofield S, Edgar LA, Fox VK, Fraeman AA, House CH, Rubin DM, Sun VZ, Van Beek JK. Orbital and In-Situ Investigation of Periodic Bedrock Ridges in Glen Torridon, Gale Crater, Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2022; 127:e2021JE007096. [PMID: 35865672 PMCID: PMC9286800 DOI: 10.1029/2021je007096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 05/03/2022] [Accepted: 05/07/2022] [Indexed: 06/15/2023]
Abstract
Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover, contains a diverse and extensive record of aeolian deposition and erosion. This study focuses on a series of regularly spaced, curvilinear, and sometimes branching bedrock ridges that occur within the Glen Torridon region on the lower northwest flank of Aeolis Mons, the central mound within Gale crater. During Curiosity's exploration of Glen Torridon between sols ∼2300-3080, the rover drove through this field of ridges, providing the opportunity for in situ observation of these features. This study uses orbiter and rover data to characterize ridge morphology, spatial distribution, compositional and material properties, and association with other aeolian features in the area. Based on these observations, we find that the Glen Torridon ridges are consistent with an origin as wind-eroded bedrock ridges, carved during the exhumation of Mount Sharp. Erosional features like the Glen Torridon ridges observed elsewhere on Mars, termed periodic bedrock ridges (PBRs), have been interpreted to form transverse to the dominant wind direction. The size and morphology of the Glen Torridon PBRs are consistent with transverse formative winds, but the orientation of nearby aeolian bedforms and bedrock erosional features raise the possibility of PBR formation by a net northeasterly wind regime. Although several formation models for the Glen Torridon PBRs are still under consideration, and questions persist about the nature of PBR-forming paleowinds, the presence of PBRs at this site provides important constraints on the depositional and erosional history of Gale crater.
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Affiliation(s)
- Kathryn M. Stack
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - William E. Dietrich
- Department of Earth and Planetary ScienceUniversity of California, BerkeleyBerkeleyCAUSA
| | - Michael P. Lamb
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Robert J. Sullivan
- Cornell Center for Astrophysics & Planetary ScienceCornell UniversityIthacaNYUSA
| | - John R. Christian
- Department of Earth and Planetary SciencesWashington University in St. LouisSt. LouisMOUSA
| | | | | | - Jonathan W. Sneed
- Department of Earth, Planetary, and Space SciencesUniversity of California, Los AngelesLos AngelesCAUSA
| | - Mackenzie Day
- Department of Earth, Planetary, and Space SciencesUniversity of California, Los AngelesLos AngelesCAUSA
| | - Mariah Baker
- Center for Earth & Planetary StudiesNational Air & Space MuseumSmithsonian InstitutionWashingtonDCUSA
| | - Raymond E. Arvidson
- Department of Earth and Planetary SciencesWashington University in St. LouisSt. LouisMOUSA
| | - Christopher M. Fedo
- Department of Earth and Planetary SciencesUniversity of Tennessee, KnoxvilleKnoxvilleTNUSA
| | - Sabrina Khan
- Department of Earth, Atmospheric, and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMAUSA
| | | | | | - Alexander B. Bryk
- Department of Earth and Planetary ScienceUniversity of California, BerkeleyBerkeleyCAUSA
| | - Shannon Cofield
- U.S. Department of the InteriorBureau of Ocean Energy ManagementWashingtonDCUSA
| | - Lauren A. Edgar
- Astrogeology Science CenterU.S. Geological SurveyFlagstaffAZUSA
| | - Valerie K. Fox
- Earth and Environmental SciencesUniversity of MinnesotaMinneapolisMNUSA
| | - Abigail A. Fraeman
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - David M. Rubin
- Earth and Planetary SciencesUniversity of California, Santa CruzSanta CruzCAUSA
| | - Vivian Z. Sun
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jason K. Van Beek
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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5
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Megaripple mechanics: bimodal transport ingrained in bimodal sands. Nat Commun 2022; 13:162. [PMID: 35013166 PMCID: PMC8748662 DOI: 10.1038/s41467-021-26985-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 10/20/2021] [Indexed: 12/03/2022] Open
Abstract
Aeolian sand transport is a major process shaping landscapes on Earth and on diverse celestial bodies. Conditions favoring bimodal sand transport, with fine-grain saltation driving coarse-grain reptation, give rise to the evolution of megaripples with a characteristic bimodal sand composition. Here, we derive a unified phase diagram for this special aeolian process and the ensuing nonequilibrium megaripple morphodynamics by means of a conceptually simple quantitative model, grounded in the grain-scale physics. We establish a well-preserved quantitative signature of bimodal aeolian transport in the otherwise highly variable grain size distributions, namely, the log-scale width (Krumbein phi scale) of their coarse-grain peaks. A comprehensive collection of terrestrial and extraterrestrial data, covering a wide range of geographical sources and environmental conditions, supports the accuracy and robustness of this unexpected theoretical finding. It could help to resolve ambiguities in the classification of terrestrial and extraterrestrial sedimentary bedforms. Megaripples are sand landforms found in wind-blown environments. A newly identified characteristic signature of the underlying bimodal sand transport process is found in the grain-size distribution on megaripples and could lend insight into transport conditions on Earth and other planetary bodies.
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Chojnacki M, Vaz DA, Silvestro S, Silva DCA. Widespread Megaripple Activity Across the North Polar Ergs of Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2021; 126:e2021JE006970. [PMID: 35096495 PMCID: PMC8793034 DOI: 10.1029/2021je006970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 11/10/2021] [Indexed: 06/14/2023]
Abstract
The most expansive dune fields on Mars surround the northern polar cap where various aeolian bedform classes are modified by wind and ice. The morphology and dynamics of these ripples, intermediate-scale bedforms (termed megaripples and Transverse Aeolian Ridges [TARs]), and sand dunes reflect information regarding regional boundary conditions. We found that populations of polar megaripples and larger TARs are distinct in terms of their morphology, spatial distribution, and mobility. Whereas regionally restricted TARs appeared degraded and static in long-baseline observations, polar megaripples were not only widespread but migrating at relatively high rates (0.13 ± 0.03 m/Earth year) and possibly more active than other regions on Mars. This high level of activity is somewhat surprising since there is limited seasonality for aeolian transport due to surficial frost and ice during the latter half of the martian year. A comprehensive analysis of an Olympia Cavi dune field estimated that the advancement of megaripples, ripples, and dunes avalanches accounted for ~1%, ~10%, and ~100%, respectively, of the total aeolian system's sand fluxes. This included dark-toned ripples that migrated the average equivalent of 9.6 ± 6 m/yr over just 22 days in northern summer-unprecedented rates for Mars. While bedform transport rates are some of the highest yet reported on Mars, the sand flux contribution between the different bedforms does not substantially vary from equatorial sites with lower rates. Seasonal off-cap sublimation winds and summer-time polar storms are attributed as the cause for the elevated activity, rather than cryospheric processes.
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Affiliation(s)
| | - David A Vaz
- Centre for Earth and Space Research of the University of Coimbra, Observatório Geofísico e Astronómico da Universidade de Coimbra, Coimbra, Portugal
| | - Simone Silvestro
- SETI Institute, Carl Sagan Center, Mountain View, CA, USA
- INAF Osservatorio Astronomico di Capodimonte, Napoli, Italia
| | - David C A Silva
- Centre for Earth and Space Research of the University of Coimbra, Observatório Geofísico e Astronómico da Universidade de Coimbra, Coimbra, Portugal
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7
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Recognition of Sedimentary Rock Occurrences in Satellite and Aerial Images of Other Worlds—Insights from Mars. REMOTE SENSING 2021. [DOI: 10.3390/rs13214296] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sedimentary rocks provide records of past surface and subsurface processes and environments. The first step in the study of the sedimentary rock record of another world is to learn to recognize their occurrences in images from instruments aboard orbiting, flyby, or aerial platforms. For two decades, Mars has been known to have sedimentary rocks; however, planet-wide identification is incomplete. Global coverage at 0.25–6 m/pixel, and observations from the Curiosity rover in Gale crater, expand the ability to recognize Martian sedimentary rocks. No longer limited to cases that are light-toned, lightly cratered, and stratified—or mimic original depositional setting (e.g., lithified deltas)—Martian sedimentary rocks include dark-toned examples, as well as rocks that are erosion-resistant enough to retain small craters as well as do lava flows. Breakdown of conglomerates, breccias, and even some mudstones, can produce a pebbly regolith that imparts a “smooth” appearance in satellite and aerial images. Context is important; sedimentary rocks remain challenging to distinguish from primary igneous rocks in some cases. Detection of ultramafic, mafic, or andesitic compositions do not dictate that a rock is igneous, and clast genesis should be considered separately from the depositional record. Mars likely has much more sedimentary rock than previously recognized.
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Piqueux S, Müller N, Grott M, Siegler M, Millour E, Forget F, Lemmon M, Golombek M, Williams N, Grant J, Warner N, Ansan V, Daubar I, Knollenberg J, Maki J, Spiga A, Banfield D, Spohn T, Smrekar S, Banerdt B. Soil Thermophysical Properties Near the InSight Lander Derived From 50 Sols of Radiometer Measurements. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2021; 126:e2021JE006859. [PMID: 35845552 PMCID: PMC9285084 DOI: 10.1029/2021je006859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/12/2021] [Accepted: 04/19/2021] [Indexed: 06/11/2023]
Abstract
Measurements from the InSight lander radiometer acquired after landing are used to characterize the thermophysical properties of the Martian soil in Homestead hollow. This data set is unique as it stems from a high measurement cadence fixed platform studying a simple well-characterized surface, and it benefits from the environmental characterization provided by other instruments. We focus on observations acquired before the arrival of a regional dust storm (near Sol 50), on the furthest observed patch of soil (i.e., ∼3.5 m away from the edge of the lander deck) where temperatures are least impacted by the presence of the lander and where the soil has been least disrupted during landing. Diurnal temperature cycles are fit using a homogenous soil configuration with a thermal inertia of 183 ± 25 J m-2 K-1 s-1/2 and an albedo of 0.16, corresponding to very fine to fine sand with the vast majority of particles smaller than 140 μm. A pre-landing assessment leveraging orbital thermal infrared data is consistent with these results, but our analysis of the full diurnal temperature cycle acquired from the ground further indicates that near surface layers with different thermophysical properties must be thin (i.e., typically within the top few mm) and deep layering with different thermophysical properties must be at least below ∼4 cm. The low thermal inertia value indicates limited soil cementation within the upper one or two skin depths (i.e., ∼4-8 cm and more), with cement volumes <<1%, which is challenging to reconcile with visible images of overhangs in pits.
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Affiliation(s)
- Sylvain Piqueux
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Nils Müller
- DLR Institute for Planetary ResearchBerlinGermany
| | | | | | | | | | | | - Matthew Golombek
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Nathan Williams
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - John Grant
- National Air and Space MuseumSmithsonian InstitutionWashingtonDCUSA
| | | | | | | | | | - Justin Maki
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | | | - Tilman Spohn
- DLR Institute for Planetary ResearchBerlinGermany
- International Space Science Institute ISSIBernSwitzerland
| | - Susan Smrekar
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Bruce Banerdt
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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9
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Dundas CM, Becerra P, Byrne S, Chojnacki M, Daubar IJ, Diniega S, Hansen CJ, Herkenhoff KE, Landis ME, McEwen AS, Portyankina G, Valantinas A. Active Mars: A Dynamic World. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2021; 126:e2021JE006876. [PMID: 35845553 PMCID: PMC9285055 DOI: 10.1029/2021je006876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 06/15/2023]
Abstract
Mars exhibits diverse surface changes at all latitudes and all seasons. Active processes include impact cratering, aeolian sand and dust transport, a variety of slope processes, changes in polar ices, and diverse effects of seasonal CO2 frost. The extent of surface change has been surprising and indicates that the present climate is capable of reshaping the surface. Activity has important implications for the Amazonian history of Mars: understanding processes is a necessary step before we can understand their implications and variations over time.
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Affiliation(s)
- Colin M. Dundas
- U.S. Geological SurveyAstrogeology Science CenterFlagstaffAZUSA
| | | | - Shane Byrne
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | | | - Ingrid J. Daubar
- Department of Earth, Environmental, and Planetary SciencesBrown UniversityProvidenceRIUSA
| | - Serina Diniega
- Jet Propulsion Laboratory/California Institute of TechnologyPasadenaCAUSA
| | | | | | - Margaret E. Landis
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | | | - Ganna Portyankina
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
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10
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Abstract
Transverse aeolian ridges (TARs) are poorly understood relict aeolian Martian surface features. Processes that create TARs are not well-constrained, and understanding their formation is complicated since they appear to share some features of ripples, megaripples, and dunes. While some evidence of multi-stage TAR formation has been documented in Nirgal Vallis, here we present additional evidence for this process at nine locations on Mars using cratering superposition between different ridge morphologies. Most occurrences of multistage evolution will not preserve the precise series of cratering and formation events documented here, which potentially means that this formative process may have been more common than even these new widespread observations suggest. This formative process can help determine the relative similarity of TARs to ripples, megaripples and dunes. Based on our observations, we conclude that primary TAR forms are most like megaripples, and that subsequent ridges formed like aqueous ripple spurs.
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11
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A lower-than-expected saltation threshold at Martian pressure and below. Proc Natl Acad Sci U S A 2021; 118:2012386118. [PMID: 33509927 DOI: 10.1073/pnas.2012386118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Aeolian sediment transport is observed to occur on Mars as well as other extraterrestrial environments, generating ripples and dunes as on Earth. The search for terrestrial analogs of planetary bedforms, as well as environmental simulation experiments able to reproduce their formation in planetary conditions, are powerful ways to question our understanding of geomorphological processes toward unusual environmental conditions. Here, we perform sediment transport laboratory experiments in a closed-circuit wind tunnel placed in a vacuum chamber and operated at extremely low pressures to show that Martian conditions belong to a previously unexplored saltation regime. The threshold wind speed required to initiate saltation is only quantitatively predicted by state-of-the art models up to a density ratio between grain and air of [Formula: see text] but unexpectedly falls to much lower values for higher density ratios. In contrast, impact ripples, whose emergence is continuously observed on the granular bed over the whole pressure range investigated, display a characteristic wavelength and propagation velocity essentially independent of pressure. A comparison of these findings with existing models suggests that sediment transport at low Reynolds number but high grain-to-fluid density ratio may be dominated by collective effects associated with grain inertia in the granular collisional layer.
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12
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Bell JF, Maki JN, Mehall GL, Ravine MA, Caplinger MA, Bailey ZJ, Brylow S, Schaffner JA, Kinch KM, Madsen MB, Winhold A, Hayes AG, Corlies P, Tate C, Barrington M, Cisneros E, Jensen E, Paris K, Crawford K, Rojas C, Mehall L, Joseph J, Proton JB, Cluff N, Deen RG, Betts B, Cloutis E, Coates AJ, Colaprete A, Edgett KS, Ehlmann BL, Fagents S, Grotzinger JP, Hardgrove C, Herkenhoff KE, Horgan B, Jaumann R, Johnson JR, Lemmon M, Paar G, Caballo-Perucha M, Gupta S, Traxler C, Preusker F, Rice MS, Robinson MS, Schmitz N, Sullivan R, Wolff MJ. The Mars 2020 Perseverance Rover Mast Camera Zoom (Mastcam-Z) Multispectral, Stereoscopic Imaging Investigation. SPACE SCIENCE REVIEWS 2021; 217:24. [PMID: 33612866 PMCID: PMC7883548 DOI: 10.1007/s11214-020-00755-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 09/25/2020] [Indexed: 05/16/2023]
Abstract
Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission's Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 μrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 μrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory Curiosity rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover's Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover's traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover's sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions.
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Affiliation(s)
| | | | | | - M. A. Ravine
- Malin Space Science Systems, Inc., San Diego, CA USA
| | | | | | - S. Brylow
- Malin Space Science Systems, Inc., San Diego, CA USA
| | | | | | | | | | | | | | - C. Tate
- Cornell Univ., Ithaca, NY USA
| | | | | | - E. Jensen
- Malin Space Science Systems, Inc., San Diego, CA USA
| | - K. Paris
- Arizona State Univ., Tempe, AZ USA
| | | | - C. Rojas
- Arizona State Univ., Tempe, AZ USA
| | | | | | | | - N. Cluff
- Arizona State Univ., Tempe, AZ USA
| | | | - B. Betts
- The Planetary Society, Pasadena, CA USA
| | | | - A. J. Coates
- Mullard Space Science Laboratory, Univ. College, London, UK
| | - A. Colaprete
- NASA/Ames Research Center, Moffett Field, CA USA
| | - K. S. Edgett
- Malin Space Science Systems, Inc., San Diego, CA USA
| | - B. L. Ehlmann
- JPL/Caltech, Pasadena, CA USA
- Caltech, Pasadena, CA USA
| | | | | | | | | | | | - R. Jaumann
- Inst. of Geological Sciences, Free University Berlin, Berlin, Germany
| | | | - M. Lemmon
- Space Science Inst., Boulder, CO USA
| | - G. Paar
- Joanneum Research, Graz, Austria
| | | | | | | | - F. Preusker
- DLR/German Aerospace Center, Berlin, Germany
| | - M. S. Rice
- Western Washington Univ., Bellingham, WA USA
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13
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Silvestro S, Chojnacki M, Vaz DA, Cardinale M, Yizhaq H, Esposito F. Megaripple Migration on Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2020; 125:e2020JE006446. [PMID: 33133993 PMCID: PMC7583471 DOI: 10.1029/2020je006446] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/09/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Aeolian megaripples, with 5- to 50-m spacing, are abundant on the surface of Mars. These features were repeatedly targeted by high-resolution orbital images, but they have never been observed to move. Thus, aeolian megaripples (especially the bright-toned ones often referred as Transverse Aeolian Ridges-TARs) have been interpreted as relict features of a past climate. In this report, we show evidence for the migration of bright-toned megaripples spaced 1 to 35 m (5 m on average) in two equatorial areas on Mars indicating that megaripples and small TARs can be active today. The moving megaripples display sand fluxes that are 2 orders of magnitudes lower than the surrounding dunes on average and, unlike similar bedforms on Earth, can migrate obliquely and longitudinally. In addition, the active megaripples in the two study areas of Syrtis Major and Mawrth Vallis show very similar flux distributions, echoing the similarities between dune crest fluxes in the two study areas and suggesting the existence of a relationship between dune and megaripple fluxes that can be explored elsewhere. Active megaripples, together with high-sand flux dunes, represent a key indicator of strong winds at the surface of Mars. A past climate with a denser atmosphere is not necessary to explain their accumulation and migration.
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Affiliation(s)
- S. Silvestro
- INAF Osservatorio Astronomico di CapodimonteNapoliItaly
- SETI InstituteMountain ViewCAUSA
| | - M. Chojnacki
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
- Planetary Science InstituteTucsonAZUSA
| | - D. A. Vaz
- Centre for Earth and Space Research of the University of CoimbraObservatório Geofísico e Astronómico da Universidade de CoimbraCoimbraPortugal
| | | | - H. Yizhaq
- Department of Solar Energy and Environmental Physics, BIDRBen‐Gurion University of the NegevBeershebaIsrael
| | - F. Esposito
- INAF Osservatorio Astronomico di CapodimonteNapoliItaly
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14
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Abstract
Recurring Slope Lineae (RSL) on Mars have been enigmatic since their discovery; their behavior resembles a seeping liquid but sources of water remain puzzling. This work demonstrates that the properties of RSL are consistent with observed behaviors of Martian and terrestrial aeolian processes. Specifically, RSL are well-explained as flows of sand that remove a thin coating of dust. Observed RSL properties are supportive of or consistent with this model, which requires no liquid water or other exotic processes, but rather indicates seasonal aeolian behavior. These settings and behaviors resemble features observed by rovers and also explain the occurrence of many slope lineae on Mars that do not meet the strict definition of RSL. This indicates that RSL can be explained simply as aeolian features. Other processes may add complexities just as they could modify the behavior of any sand dune.
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Affiliation(s)
- Colin M. Dundas
- U.S. Geological Survey, Astrogeology Science Center, 2255 N. Gemini Dr., Flagstaff, AZ 86001, USA
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15
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Ruff SW, Campbell KA, Van Kranendonk MJ, Rice MS, Farmer JD. The Case for Ancient Hot Springs in Gusev Crater, Mars. ASTROBIOLOGY 2020; 20:475-499. [PMID: 31621375 PMCID: PMC7133449 DOI: 10.1089/ast.2019.2044] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 09/11/2019] [Indexed: 05/19/2023]
Abstract
The origin and age of opaline silica deposits discovered by the Spirit rover adjacent to the Home Plate feature in the Columbia Hills of Gusev crater remains debated, in part because of their proximity to sulfur-rich soils. Processes related to fumarolic activity and to hot springs and/or geysers are the leading candidates. Both processes are known to produce opaline silica on Earth, but with differences in composition, morphology, texture, and stratigraphy. Here, we incorporate new and existing observations of the Home Plate region with observations from field and laboratory work to address the competing hypotheses. The results, which include new evidence for a hot spring vent mound, demonstrate that a volcanic hydrothermal system manifesting both hot spring/geyser and fumarolic activity best explains the opaline silica rocks and proximal S-rich materials, respectively. The opaline silica rocks most likely are sinter deposits derived from hot spring activity. Stratigraphic evidence indicates that their deposition occurred before the emplacement of the volcaniclastic deposits comprising Home Plate and nearby ridges. Because sinter deposits throughout geologic history on Earth preserve evidence for microbial life, they are a key target in the search for ancient life on Mars.
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Affiliation(s)
- Steven W. Ruff
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
- Address correspondence to: Steven W. Ruff, School of Earth and Space Exploration, Arizona State University, Mars Space Flight Facility, Moeur Building Room 131, Tempe, AZ 85287-6305
| | - Kathleen A. Campbell
- School of Environment and Te Ao Mārama—Centre for Fundamental Inquiry, The University of Auckland, Auckland, New Zealand
| | - Martin J. Van Kranendonk
- Australian Centre for Astrobiology, School of Biological, Earth and Environmental Sciences, University of New South Wales Sydney, Sydney, Australia
| | - Melissa S. Rice
- Department of Geology, Western Washington University, Bellingham, Washington
| | - Jack D. Farmer
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
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16
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Distribution and Morphologies of Transverse Aeolian Ridges in ExoMars 2020 Rover Landing Site. REMOTE SENSING 2019. [DOI: 10.3390/rs11080912] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Aeolian processes are believed to play a major role in the landscape evolution of Mars. Investigations on Martian aeolian landforms such as ripples, transverse aeolian ridges (TARs), and dunes, and aeolian sediment flux measurements are important to enhance our understanding of past and present wind regimes, the ongoing dust cycle, landscape evolution, and geochemistry. These aeolian bedforms are often comprised of loose sand and sharply undulating topography and thus pose a threat to mobility and maneuvers of Mars rovers. Here we present a first-hand account of the distribution, morphologies, and morphometrics of TARs in Oxia Planum, the recently selected ExoMars 2020 Rover landing site. The gridded mapping was performed for contiguous stretches of TARs within all the landing ellipses using 57 sub-meter high resolution imaging science experiment (HiRISE) scenes. We also provide the morphological descriptions for all types of TARs present within the landing ellipses. We use HiRISE digital terrain models (DTMs) along with the images to derive morphometric information for TARs in Oxia Planum. In general, the average areal TAR coverage was found to be 5.4% (±4.9% standard deviation), increasing from west to east within the landing ellipses. We report the average TAR morphometrics in the form of crest–ridge width (131.1 ± 106.2 m), down-wind TAR length (17.6 ± 10.1 m), wavelength (37.3 ± 11.6 m), plan view aspect ratio (7.1 ± 2.3), inter-bedform spacing (2.1 ± 1.1), slope (10.6° ± 6.1°), predominant orientations (NE-SW and E-W), and height (1.2 ± 0.8 m). While simple TARs are predominant, we report other TAR morphologies such as forked TAR, wavy TAR with associated smaller secondary ripples, barchan-like TAR, networked TAR, and mini-TARs from the region. Our results can help in planning the rover traverses in terms of both safe passage and scientific returns favoring aeolian research, particularly improving our understanding of TARs.
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17
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Bak EN, Larsen MG, Jensen SK, Nørnberg P, Moeller R, Finster K. Wind-Driven Saltation: An Overlooked Challenge for Life on Mars. ASTROBIOLOGY 2019; 19:497-505. [PMID: 30407074 DOI: 10.1089/ast.2018.1856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Numerous studies have demonstrated that the martian surface environment is hostile to life because of its rough radiation climate and the reactive chemistry of the regolith. Physical processes such as erosion and transport of mineral particles by wind-driven saltation have hitherto not been considered as a life hazard. We report a series of experiments where bacterial endospores (spores of Bacillus subtilis) were exposed to a simulated saltating martian environment. We observed that 50% of the spores that are known to be highly resistant to radiation and oxidizing chemicals were destroyed by saltation-mediated abrasion within one minute. Scanning electron micrographs show that the spores were not only damaged by abrasion but were eradicated during the saltation process. We suggest that abrasion mediated by wind-driven saltation should be included as a factor that defines the habitability of the martian surface environment. The process may efficiently protect the martian surface from forward contamination with terrestrial microbial life-forms. Abrasion mediated by wind-driven saltation should also be considered as a major challenge to indigenous martian surface life if it exists/existed.
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Affiliation(s)
- E N Bak
- 1 Department of Bioscience, Aarhus University , Aarhus, Denmark
| | - M G Larsen
- 1 Department of Bioscience, Aarhus University , Aarhus, Denmark
| | - S K Jensen
- 2 Department of Chemistry, Aarhus University , Aarhus, Denmark
| | - P Nørnberg
- 1 Department of Bioscience, Aarhus University , Aarhus, Denmark
| | - R Moeller
- 3 Institute of Aerospace Medicine , Radiation Biology Department, Space Microbiology Research Group, German Aerospace Center (DLR e.V.), Cologne (Köln), Germany
| | - K Finster
- 1 Department of Bioscience, Aarhus University , Aarhus, Denmark
- 4 Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University , Aarhus, Denmark
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18
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Chojnacki M, Banks M, Urso A. Wind-Driven Erosion and Exposure Potential at Mars 2020 Rover Candidate-Landing Sites. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2018; 123:468-488. [PMID: 29568719 PMCID: PMC5859260 DOI: 10.1002/2017je005460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Aeolian processes have likely been the predominant geomorphic agent for most of Mars' history and have the potential to produce relatively young exposure ages for geologic units. Thus, identifying local evidence for aeolian erosion is highly relevant to the selection of landing sites for future missions, such as the Mars 2020 Rover mission that aims to explore astrobiologically relevant ancient environments. Here we investigate wind-driven activity at eight Mars 2020 candidate-landing sites to constrain erosion potential at these locations. To demonstrate our methods, we found that contemporary dune-derived abrasion rates were in agreement with rover-derived exhumation rates at Gale crater and could be employed elsewhere. The Holden crater candidate site was interpreted to have low contemporary erosion rates, based on the presence of a thick sand coverage of static ripples. Active ripples at the Eberswalde and southwest Melas sites may account for local erosion and the dearth of small craters. Moderate-flux regional dunes near Mawrth Vallis were deemed unrepresentative of the candidate site, which is interpreted to currently be experiencing low levels of erosion. The Nili Fossae site displayed the most unambiguous evidence for local sand transport and erosion, likely yielding relatively young exposure ages. The downselected Jezero crater and northeast Syrtis sites had high-flux neighboring dunes and exhibited substantial evidence for sediment pathways across their ellipses. Both sites had relatively high estimated abrasion rates, which would yield young exposure ages. The downselected Columbia Hills site lacked evidence for sand movement, and contemporary local erosion rates are estimated to be relatively low.
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Affiliation(s)
- Matthew Chojnacki
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
| | - Maria Banks
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | - Anna Urso
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
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19
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Ewing RC, Lapotre MGA, Lewis KW, Day M, Stein N, Rubin DM, Sullivan R, Banham S, Lamb MP, Bridges NT, Gupta S, Fischer WW. Sedimentary processes of the Bagnold Dunes: Implications for the eolian rock record of Mars. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2017; 122:2544-2573. [PMID: 29497590 PMCID: PMC5815379 DOI: 10.1002/2017je005324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 06/19/2017] [Accepted: 06/26/2017] [Indexed: 05/31/2023]
Abstract
The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were present on all dune slopes and had a size and shape similar to their terrestrial counterpart. Grainfall and grainflow occurred on dune and large-ripple lee slopes. Lee slopes were ~29° where grainflows were present and ~33° where grainfall was present. These slopes are interpreted as the dynamic and static angles of repose, respectively. Grain size measured on an undisturbed impact ripple ranges between 50 μm and 350 μm with an intermediate axis mean size of 113 μm (median: 103 μm). Dissimilar to dune eolian processes on Earth, large, meter-scale ripples were present on all dune slopes. Large ripples had nearly symmetric to strongly asymmetric topographic profiles and heights ranging between 12 cm and 28 cm. The composite observations of the modern sedimentary processes highlight that the Martian eolian rock record is likely different from its terrestrial counterpart because of the large ripples, which are expected to engender a unique scale of cross stratification. More broadly, however, in the Bagnold Dune Field as on Earth, dune-field pattern dynamics and basin-scale boundary conditions will dictate the style and distribution of sedimentary processes.
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Affiliation(s)
- R. C. Ewing
- Department of Geology and GeophysicsTexas A&M UniversityCollege StationTexasUSA
| | - M. G. A. Lapotre
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCaliforniaUSA
| | - K. W. Lewis
- Department of Earth and Planetary SciencesJohns Hopkins UniversityBaltimoreMarylandUSA
| | - M. Day
- Jackson School of Geosciences, Department of Geological SciencesUniversity of Texas at AustinAustinTexasUSA
| | - N. Stein
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCaliforniaUSA
| | - D. M. Rubin
- Department of Earth and Planetary SciencesUniversity of CaliforniaSanta CruzCaliforniaUSA
| | - R. Sullivan
- Department of AstronomyCornell UniversityIthacaNew YorkUSA
| | - S. Banham
- Department of Earth Science and EngineeringImperial College LondonLondonUK
| | - M. P. Lamb
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCaliforniaUSA
| | - N. T. Bridges
- The Johns Hopkins University Applied Physics LaboratoryLaurelMarylandUSA
| | - S. Gupta
- Department of Earth Science and EngineeringImperial College LondonLondonUK
| | - W. W. Fischer
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCaliforniaUSA
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20
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Ehlmann BL, Edgett KS, Sutter B, Achilles CN, Litvak ML, Lapotre MGA, Sullivan R, Fraeman AA, Arvidson RE, Blake DF, Bridges NT, Conrad PG, Cousin A, Downs RT, Gabriel TSJ, Gellert R, Hamilton VE, Hardgrove C, Johnson JR, Kuhn S, Mahaffy PR, Maurice S, McHenry M, Meslin PY, Ming DW, Minitti ME, Morookian JM, Morris RV, O'Connell-Cooper CD, Pinet PC, Rowland SK, Schröder S, Siebach KL, Stein NT, Thompson LM, Vaniman DT, Vasavada AR, Wellington DF, Wiens RC, Yen AS. Chemistry, mineralogy, and grain properties at Namib and High dunes, Bagnold dune field, Gale crater, Mars: A synthesis of Curiosity rover observations. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2017; 122:2510-2543. [PMID: 29497589 DOI: 10.1002/2016je005225] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 05/25/2023]
Abstract
The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 μm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.
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21
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Ehlmann BL, Edgett KS, Sutter B, Achilles CN, Litvak ML, Lapotre MGA, Sullivan R, Fraeman AA, Arvidson RE, Blake DF, Bridges NT, Conrad PG, Cousin A, Downs RT, Gabriel TSJ, Gellert R, Hamilton VE, Hardgrove C, Johnson JR, Kuhn S, Mahaffy PR, Maurice S, McHenry M, Meslin P, Ming DW, Minitti ME, Morookian JM, Morris RV, O'Connell‐Cooper CD, Pinet PC, Rowland SK, Schröder S, Siebach KL, Stein NT, Thompson LM, Vaniman DT, Vasavada AR, Wellington DF, Wiens RC, Yen AS. Chemistry, mineralogy, and grain properties at Namib and High dunes, Bagnold dune field, Gale crater, Mars: A synthesis of Curiosity rover observations. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2017; 122:2510-2543. [PMID: 29497589 PMCID: PMC5815393 DOI: 10.1002/2017je005267] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 05/31/2023]
Abstract
The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 μm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 μm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.
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22
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Chojnacki M, Fenton LK. The Geologic Exploration of the Bagnold Dune Field at Gale Crater by the Curiosity Rover. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2017; 122:2216-2222. [PMID: 29564198 PMCID: PMC5857957 DOI: 10.1002/2017je005455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The Mars Science Laboratory rover Curiosity engaged in a monthlong campaign investigating the Bagnold dune field in Gale crater. What represents the first in situ investigation of a dune field on another planet has resulted in a number of discoveries. Collectively, the Curiosity rover team has compiled the most comprehensive survey of any extraterrestrial aeolian system visited to date with results that yield important insights into a number of processes, including sediment transport, bed form morphology and structure, chemical and physical composition of aeolian sand, and wind regime characteristics. These findings and more are provided in detail by the JGR-Planets Special Issue Curiosity's Bagnold Dunes Campaign, Phase I.
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Affiliation(s)
- Matthew Chojnacki
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
| | - Lori K Fenton
- Carl Sagan Center, SETI Institute, Mountain View, CA, USA
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Chojnacki M, Urso A, Fenton LK, Michaels TI. Aeolian dune sediment flux heterogeneity in Meridiani Planum, Mars. AEOLIAN RESEARCH 2017; 26:73-88. [PMID: 29576818 PMCID: PMC5863747 DOI: 10.1016/j.aeolia.2016.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
It is now known unambiguously that wind-driven bedform activity is occurring on the surface of Mars today, including early detections of active sand dunes in Meridiani Planum's Endeavour crater. Many of these reports are only based on a few sets of observations of relatively isolated bedforms and lack regional context. Here, we investigate aeolian activity across central Meridiani Planum and test the hypothesis that dune sites surrounding Endeavour crater are also active and part of region-wide sediment migration driven by northwesterly winds. All 13 dune fields investigated clearly showed evidence for activity and the majority exhibited dune migration (average rates of 0.6 m/Earth-year). Observations indicate substantial geographic and temporal heterogeneity of dune crest fluxes across the area and per site. Locations with multiple time steps indicate dune sand fluxes can vary by a factor of five, providing evidence for short periods of rapid migration followed by near-stagnation. In contrast, measurements at other sites are nearly identical, indicating that some dunes are in a steady-state as they migrate. The observed sediment transport direction was consistent with a regional northeasterly-to-northwesterly wind regime, revealing more variations than were appreciated from earlier, more localized studies. Craters containing shallow, degraded, flat-floored interiors tended to have dunes with high sediment fluxes/activity, whereas local kilometer-scale topographic obstructions (e.g., central peaks, yardangs) were found to be inversely correlated with dune mobility. Finally, the previous, more limited detections of dune activity in Endeavour crater have been shown to be representative of a broader, region-wide pattern of dune motion.
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Affiliation(s)
- Matthew Chojnacki
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
- Corresponding author at: Lunar and Planetary Lab, University of Arizona, 1541 E. University Blvd, Tucson, AZ 85721-0063, USA. (M. Chojnacki)
| | - Anna Urso
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - Lori K. Fenton
- Carl Sagan Center at the SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043, USA
| | - Timothy I. Michaels
- Carl Sagan Center at the SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043, USA
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24
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Lämmel M, Dzikowski K, Kroy K, Oger L, Valance A. Grain-scale modeling and splash parametrization for aeolian sand transport. Phys Rev E 2017; 95:022902. [PMID: 28297955 DOI: 10.1103/physreve.95.022902] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Indexed: 11/07/2022]
Abstract
The collision of a spherical grain with a granular bed is commonly parametrized by the splash function, which provides the velocity of the rebounding grain and the velocity distribution and number of ejected grains. Starting from elementary geometric considerations and physical principles, like momentum conservation and energy dissipation in inelastic pair collisions, we derive a rebound parametrization for the collision of a spherical grain with a granular bed. Combined with a recently proposed energy-splitting model [Ho et al., Phys. Rev. E 85, 052301 (2012)PLEEE81539-375510.1103/PhysRevE.85.052301] that predicts how the impact energy is distributed among the bed grains, this yields a coarse-grained but complete characterization of the splash as a function of the impact velocity and the impactor-bed grain-size ratio. The predicted mean values of the rebound angle, total and vertical restitution, ejection speed, and number of ejected grains are in excellent agreement with experimental literature data and with our own discrete-element computer simulations. We extract a set of analytical asymptotic relations for shallow impact geometries, which can readily be used in coarse-grained analytical modeling or computer simulations of geophysical particle-laden flows.
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Affiliation(s)
- Marc Lämmel
- Institut für Theoretische Physik, Universität Leipzig, Postfach 100920, 04009 Leipzig, Germany
| | - Kamil Dzikowski
- Institut für Theoretische Physik, Universität Leipzig, Postfach 100920, 04009 Leipzig, Germany
| | - Klaus Kroy
- Institut für Theoretische Physik, Universität Leipzig, Postfach 100920, 04009 Leipzig, Germany
| | - Luc Oger
- Institut de Physique de Rennes, CNRS UMR 6251, Université de Rennes I, 35042 Rennes, France
| | - Alexandre Valance
- Institut de Physique de Rennes, CNRS UMR 6251, Université de Rennes I, 35042 Rennes, France
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25
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Ruff SW, Farmer JD. Silica deposits on Mars with features resembling hot spring biosignatures at El Tatio in Chile. Nat Commun 2016; 7:13554. [PMID: 27853166 PMCID: PMC5473637 DOI: 10.1038/ncomms13554] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 10/13/2016] [Indexed: 11/09/2022] Open
Abstract
The Mars rover Spirit encountered outcrops and regolith composed of opaline silica (amorphous SiO2·nH2O) in an ancient volcanic hydrothermal setting in Gusev crater. An origin via either fumarole-related acid-sulfate leaching or precipitation from hot spring fluids was suggested previously. However, the potential significance of the characteristic nodular and mm-scale digitate opaline silica structures was not recognized. Here we report remarkably similar features within active hot spring/geyser discharge channels at El Tatio in northern Chile, where halite-encrusted silica yields infrared spectra that are the best match yet to spectra from Spirit. Furthermore, we show that the nodular and digitate silica structures at El Tatio that most closely resemble those on Mars include complex sedimentary structures produced by a combination of biotic and abiotic processes. Although fully abiotic processes are not ruled out for the Martian silica structures, they satisfy an a priori definition of potential biosignatures.
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Affiliation(s)
- Steven W Ruff
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287-6305, USA
| | - Jack D Farmer
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287-6305, USA
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26
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Lapotre MGA, Ewing RC, Lamb MP, Fischer WW, Grotzinger JP, Rubin DM, Lewis KW, Ballard MJ, Day M, Gupta S, Banham SG, Bridges NT, Des Marais DJ, Fraeman AA, Grant JA, Herkenhoff KE, Ming DW, Mischna MA, Rice MS, Sumner DY, Vasavada AR, Yingst RA. Large wind ripples on Mars: A record of atmospheric evolution. Science 2016; 353:55-8. [DOI: 10.1126/science.aaf3206] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/31/2016] [Indexed: 11/03/2022]
Affiliation(s)
- M. G. A. Lapotre
- Division of Geological and Planetary Science, California Institute of Technology, Pasadena, CA 91125, USA
| | - R. C. Ewing
- Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USA
| | - M. P. Lamb
- Division of Geological and Planetary Science, California Institute of Technology, Pasadena, CA 91125, USA
| | - W. W. Fischer
- Division of Geological and Planetary Science, California Institute of Technology, Pasadena, CA 91125, USA
| | - J. P. Grotzinger
- Division of Geological and Planetary Science, California Institute of Technology, Pasadena, CA 91125, USA
| | - D. M. Rubin
- Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - K. W. Lewis
- Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - M. J. Ballard
- Department of Geology and Geophysics, Texas A&M University, College Station, TX 77843, USA
| | - M. Day
- Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - S. Gupta
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
| | - S. G. Banham
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
| | - N. T. Bridges
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA
| | | | - A. A. Fraeman
- Division of Geological and Planetary Science, California Institute of Technology, Pasadena, CA 91125, USA
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - J. A. Grant
- National Air and Space Museum, Smithsonian Institution, Washington, DC 20560, USA
| | - K. E. Herkenhoff
- Astrogeology Science Center, U.S. Geological Survey, Flagstaff, AZ 86001-1698, USA
| | - D. W. Ming
- NASA Johnson Space Center, Houston, TX 77058, USA
| | - M. A. Mischna
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M. S. Rice
- Geology Department, Western Washington University, Bellingham, WA 98225-9080, USA
| | - D. Y. Sumner
- Department of Earth and Planetary Sciences, University of California, Davis, CA 95616, USA
| | - A. R. Vasavada
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - R. A. Yingst
- Planetary Science Institute, Tucson, AZ 85719, USA
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27
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Read PL, Lewis SR, Mulholland DP. The physics of Martian weather and climate: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2015; 78:125901. [PMID: 26534887 DOI: 10.1088/0034-4885/78/12/125901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The planet Mars hosts an atmosphere that is perhaps the closest in terms of its meteorology and climate to that of the Earth. But Mars differs from Earth in its greater distance from the Sun, its smaller size, its lack of liquid oceans and its thinner atmosphere, composed mainly of CO(2). These factors give Mars a rather different climate to that of the Earth. In this article we review various aspects of the martian climate system from a physicist's viewpoint, focusing on the processes that control the martian environment and comparing these with corresponding processes on Earth. These include the radiative and thermodynamical processes that determine the surface temperature and vertical structure of the atmosphere, the fluid dynamics of its atmospheric motions, and the key cycles of mineral dust and volatile transport. In many ways, the climate of Mars is as complicated and diverse as that of the Earth, with complex nonlinear feedbacks that affect its response to variations in external forcing. Recent work has shown that the martian climate is anything but static, but is almost certainly in a continual state of transient response to slowly varying insolation associated with cyclic variations in its orbit and rotation. We conclude with a discussion of the physical processes underlying these long- term climate variations on Mars, and an overview of some of the most intriguing outstanding problems that should be a focus for future observational and theoretical studies.
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Affiliation(s)
- P L Read
- Atmospheric, Oceanic & Planetary Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
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28
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Kinch KM, Bell JF, Goetz W, Johnson JR, Joseph J, Madsen MB, Sohl-Dickstein J. Dust deposition on the decks of the Mars Exploration Rovers: 10 years of dust dynamics on the Panoramic Camera calibration targets. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2015; 2:144-172. [PMID: 27981072 PMCID: PMC5125412 DOI: 10.1002/2014ea000073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/09/2015] [Accepted: 03/26/2015] [Indexed: 05/13/2023]
Abstract
The Panoramic Cameras on NASA's Mars Exploration Rovers have each returned more than 17,000 images of their calibration targets. In order to make optimal use of this data set for reflectance calibration, a correction must be made for the presence of air fall dust. Here we present an improved dust correction procedure based on a two-layer scattering model, and we present a dust reflectance spectrum derived from long-term trends in the data set. The dust on the calibration targets appears brighter than dusty areas of the Martian surface. We derive detailed histories of dust deposition and removal revealing two distinct environments: At the Spirit landing site, half the year is dominated by dust deposition, the other half by dust removal, usually in brief, sharp events. At the Opportunity landing site the Martian year has a semiannual dust cycle with dust removal happening gradually throughout two removal seasons each year. The highest observed optical depth of settled dust on the calibration target is 1.5 on Spirit and 1.1 on Opportunity (at 601 nm). We derive a general prediction for dust deposition rates of 0.004 ± 0.001 in units of surface optical depth deposited per sol (Martian solar day) per unit atmospheric optical depth. We expect this procedure to lead to improved reflectance-calibration of the Panoramic Camera data set. In addition, it is easily adapted to similar data sets from other missions in order to deliver improved reflectance calibration as well as data on dust reflectance properties and deposition and removal history.
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Affiliation(s)
- Kjartan M Kinch
- Niels Bohr Institute University of Copenhagen Copenhagen Denmark
| | - James F Bell
- School of Earth and Space Exploration Arizona State University Phoenix Arizona USA
| | - Walter Goetz
- Max Planck Institute for Solar System Research Göttingen Germany
| | - Jeffrey R Johnson
- Applied Physics Laboratory Johns Hopkins University Laurel Maryland USA
| | - Jonathan Joseph
- Department of Astronomy Cornell University Ithaca New York USA
| | - Morten Bo Madsen
- Niels Bohr Institute University of Copenhagen Copenhagen Denmark
| | - Jascha Sohl-Dickstein
- Neural Dynamics and Computation Laboratory Stanford University Stanford California USA
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29
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Blake DF, Morris RV, Kocurek G, Morrison SM, Downs RT, Bish D, Ming DW, Edgett KS, Rubin D, Goetz W, Madsen MB, Sullivan R, Gellert R, Campbell I, Treiman AH, McLennan SM, Yen AS, Grotzinger J, Vaniman DT, Chipera SJ, Achilles CN, Rampe EB, Sumner D, Meslin PY, Maurice S, Forni O, Gasnault O, Fisk M, Schmidt M, Mahaffy P, Leshin LA, Glavin D, Steele A, Freissinet C, Navarro-González R, Yingst RA, Kah LC, Bridges N, Lewis KW, Bristow TF, Farmer JD, Crisp JA, Stolper EM, Des Marais DJ, Sarrazin P. Curiosity at Gale crater, Mars: characterization and analysis of the Rocknest sand shadow. Science 2013; 341:1239505. [PMID: 24072928 DOI: 10.1126/science.1239505] [Citation(s) in RCA: 231] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The Rocknest aeolian deposit is similar to aeolian features analyzed by the Mars Exploration Rovers (MERs) Spirit and Opportunity. The fraction of sand <150 micrometers in size contains ~55% crystalline material consistent with a basaltic heritage and ~45% x-ray amorphous material. The amorphous component of Rocknest is iron-rich and silicon-poor and is the host of the volatiles (water, oxygen, sulfur dioxide, carbon dioxide, and chlorine) detected by the Sample Analysis at Mars instrument and of the fine-grained nanophase oxide component first described from basaltic soils analyzed by MERs. The similarity between soils and aeolian materials analyzed at Gusev Crater, Meridiani Planum, and Gale Crater implies locally sourced, globally similar basaltic materials or globally and regionally sourced basaltic components deposited locally at all three locations.
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Affiliation(s)
- D F Blake
- National Aeronautics and Space Administration Ames Research Center, Moffett Field, CA 94035, USA.
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30
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Kok JF, Parteli EJR, Michaels TI, Karam DB. The physics of wind-blown sand and dust. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2012; 75:106901. [PMID: 22982806 DOI: 10.1088/0034-4885/75/10/106901] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.
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Affiliation(s)
- Jasper F Kok
- Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA.
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31
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Planning for Mars returned sample science: final report of the MSR End-to-End International Science Analysis Group (E2E-iSAG). ASTROBIOLOGY 2012; 12:175-230. [PMID: 22468886 DOI: 10.1089/ast.2011.0805] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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32
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McGlynn IO, Fedo CM, McSween HY. Soil mineralogy at the Mars Exploration Rover landing sites: An assessment of the competing roles of physical sorting and chemical weathering. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003861] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Gheynani BT, Emami-Razavi M, Taylor PA. Thermophoresis and dust devils on the planet Mars. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:056305. [PMID: 22181496 DOI: 10.1103/physreve.84.056305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 08/08/2011] [Indexed: 05/31/2023]
Abstract
In the Martian atmosphere dust is abundant and is continuously replenished by the entrainment of materials and sediments from the surface of the planet. The sediment concentrations are particularly high and noticeable in whirlwinds, also known as dust devils. Assuming the thermophoresis force as the main driver of dust particles lifting from the surface, the dust process of the Martian atmosphere and its naturally formed dust devils are investigated for the northern polar region of the planet. Our simulated convective boundary layer shows that it may be unlikely that visible dust devils are formed only due to thermophoresis effects and some other lifting mechanisms are required.
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Affiliation(s)
- Babak T Gheynani
- Centre for Research in Earth and Space Science, York University, Toronto, Ontario, Canada
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34
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Ruff SW, Farmer JD, Calvin WM, Herkenhoff KE, Johnson JR, Morris RV, Rice MS, Arvidson RE, Bell JF, Christensen PR, Squyres SW. Characteristics, distribution, origin, and significance of opaline silica observed by the Spirit rover in Gusev crater, Mars. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010je003767] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Chojnacki M, Burr DM, Moersch JE, Michaels TI. Orbital observations of contemporary dune activity in Endeavor crater, Meridiani Planum, Mars. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010je003675] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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McSween HY, McGlynn IO, Rogers AD. Determining the modal mineralogy of Martian soils. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003582] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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37
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Geissler PE, Sullivan R, Golombek M, Johnson JR, Herkenhoff K, Bridges N, Vaughan A, Maki J, Parker T, Bell J. Gone with the wind: Eolian erasure of the Mars Rover tracks. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003674] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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38
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Golombek M, Robinson K, McEwen A, Bridges N, Ivanov B, Tornabene L, Sullivan R. Constraints on ripple migration at Meridiani Planum from Opportunity and HiRISE observations of fresh craters. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003628] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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39
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Greeley R, Waller DA, Cabrol NA, Landis GA, Lemmon MT, Neakrase LDV, Pendleton Hoffer M, Thompson SD, Whelley PL. Gusev Crater, Mars: Observations of three dust devil seasons. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010je003608] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Goetz W, Pike WT, Hviid SF, Madsen MB, Morris RV, Hecht MH, Staufer U, Leer K, Sykulska H, Hemmig E, Marshall J, Morookian JM, Parrat D, Vijendran S, Bos BJ, El Maarry MR, Keller HU, Kramm R, Markiewicz WJ, Drube L, Blaney D, Arvidson RE, Bell JF, Reynolds R, Smith PH, Woida P, Woida R, Tanner R. Microscopy analysis of soils at the Phoenix landing site, Mars: Classification of soil particles and description of their optical and magnetic properties. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009je003437] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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41
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Kok JF. Difference in the wind speeds required for initiation versus continuation of sand transport on mars: implications for dunes and dust storms. PHYSICAL REVIEW LETTERS 2010; 104:074502. [PMID: 20366891 DOI: 10.1103/physrevlett.104.074502] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Indexed: 05/16/2023]
Abstract
Much of the surface of Mars is covered by dunes, ripples, and other features formed by the blowing of sand by wind, known as saltation. In addition, saltation loads the atmosphere with dust aerosols, which dominate the Martian climate. We show here that saltation can be maintained on Mars by wind speeds an order of magnitude less than required to initiate it. We further show that this hysteresis effect causes saltation to occur for much lower wind speeds than previously thought. These findings have important implications for the formation of dust storms, sand dunes, and ripples on Mars.
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Affiliation(s)
- Jasper F Kok
- Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA.
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