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Wilson CF, Marcq E, Gillmann C, Widemann T, Korablev O, Mueller NT, Lefèvre M, Rimmer PB, Robert S, Zolotov MY. Possible Effects of Volcanic Eruptions on the Modern Atmosphere of Venus. SPACE SCIENCE REVIEWS 2024; 220:31. [PMID: 38585189 PMCID: PMC10997549 DOI: 10.1007/s11214-024-01054-5] [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: 04/26/2023] [Accepted: 02/01/2024] [Indexed: 04/09/2024]
Abstract
This work reviews possible signatures and potential detectability of present-day volcanically emitted material in the atmosphere of Venus. We first discuss the expected composition of volcanic gases at present time, addressing how this is related to mantle composition and atmospheric pressure. Sulfur dioxide, often used as a marker of volcanic activity in Earth's atmosphere, has been observed since late 1970s to exhibit variability at the Venus' cloud tops at time scales from hours to decades; however, this variability may be associated with solely atmospheric processes. Water vapor is identified as a particularly valuable tracer for volcanic plumes because it can be mapped from orbit at three different tropospheric altitude ranges, and because of its apparent low background variability. We note that volcanic gas plumes could be either enhanced or depleted in water vapor compared to the background atmosphere, depending on magmatic volatile composition. Non-gaseous components of volcanic plumes, such as ash grains and/or cloud aerosol particles, are another investigation target of orbital and in situ measurements. We discuss expectations of in situ and remote measurements of volcanic plumes in the atmosphere with particular focus on the upcoming DAVINCI, EnVision and VERITAS missions, as well as possible future missions.
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Affiliation(s)
- Colin F. Wilson
- European Space Agency, Keplerlaan 1, 2201, AZ Noordwijk, The Netherlands
- Physics Dept, Oxford University, Oxford, OX1 3PU UK
| | - Emmanuel Marcq
- LATMOS/IPSL, UVSQ Sorbonne Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France
| | - Cédric Gillmann
- Institut für Geophysik, Geophysical Fluid Dynamics, ETH Zurich, Sonneggstraße 5, 8092 Zürich, Switzerland
| | - Thomas Widemann
- LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 5 place Jules Janssen, 92195 Meudon, France
- Université Paris-Saclay, UVSQ, DYPAC, 78000 Versailles, France
| | - Oleg Korablev
- Space Research Institute (IKI), Russian Academy of Sciences, Moscow, 117997 Russia
| | - Nils T. Mueller
- Institute for Planetary Research, DLR, Rutherfordstraße 2, 12489 Berlin, Germany
- Institute of Geosciences, Freie Universität Berlin, Malteserstr. 74-100, 12249 Berlin, Germany
| | - Maxence Lefèvre
- LATMOS/IPSL, UVSQ Sorbonne Université Paris-Saclay, Sorbonne Université, CNRS, Guyancourt, France
| | - Paul B. Rimmer
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE UK
| | - Séverine Robert
- Royal Belgian Institute for Space Aeronomy, Brussels, Belgium
| | - Mikhail Y. Zolotov
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 USA
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2
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Styczinski MJ, Cooper ZS, Glaser DM, Lehmer O, Mierzejewski V, Tarnas J. Chapter 7: Assessing Habitability Beyond Earth. ASTROBIOLOGY 2024; 24:S143-S163. [PMID: 38498826 DOI: 10.1089/ast.2021.0097] [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: 03/20/2024]
Abstract
All known life on Earth inhabits environments that maintain conditions between certain extremes of temperature, chemical composition, energy availability, and so on (Chapter 6). Life may have emerged in similar environments elsewhere in the Solar System and beyond. The ongoing search for life elsewhere mainly focuses on those environments most likely to support life, now or in the past-that is, potentially habitable environments. Discussion of habitability is necessarily based on what we know about life on Earth, as it is our only example. This chapter gives an overview of the known and presumed requirements for life on Earth and discusses how these requirements can be used to assess the potential habitability of planetary bodies across the Solar System and beyond. We first consider the chemical requirements of life and potential feedback effects that the presence of life can have on habitable conditions, and then the planetary, stellar, and temporal requirements for habitability. We then review the state of knowledge on the potential habitability of bodies across the Solar System and exoplanets, with a particular focus on Mars, Venus, Europa, and Enceladus. While reviewing the case for the potential habitability of each body, we summarize the most prominent and impactful studies that have informed the perspective on where habitable environments are likely to be found.
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Affiliation(s)
- M J Styczinski
- University of Washington, Seattle, Washington, USA
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Z S Cooper
- University of Washington, Seattle, Washington, USA
| | - D M Glaser
- School of Molecular Sciences, Arizona State University, Tempe, Arizona, USA
| | - O Lehmer
- NASA Ames Research Center, Moffett Field, California, USA
| | - V Mierzejewski
- School of Earth and Space Exploration, Arizona State University, Arizona, USA
| | - J Tarnas
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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3
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Civiš S, Pastorek A, Ferus M, Yurchenko SN, Boudjema NI. Infrared Spectra of Small Radicals for Exoplanetary Spectroscopy: OH, NH, CN and CH: The State of Current Knowledge. Molecules 2023; 28:molecules28083362. [PMID: 37110598 PMCID: PMC10143568 DOI: 10.3390/molecules28083362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/29/2023] Open
Abstract
In this study, we present a current state-of-the-art review of middle-to-near IR emission spectra of four simple astrophysically relevant molecular radicals-OH, NH, CN and CH. The spectra of these radicals were measured by means of time-resolved Fourier transform infrared spectroscopy in the 700-7500 cm-1 spectral range and with 0.07-0.02 cm-1 spectral resolution. The radicals were generated in a glow discharge of gaseous mixtures in a specially designed discharge cell. The spectra of short-lived radicals published here are of great importance, especially for the detailed knowledge and study of the composition of exoplanetary atmospheres in selected new planets. Today, with the help of the James Webb telescope and upcoming studies with the help of Plato and Ariel satellites, when the investigated spectral area is extended into the infrared spectral range, it means that detailed knowledge of the infrared spectra of not only stable molecules but also the spectra of short-lived radicals or ions, is indispensable. This paper follows a simple structure. Each radical is described in a separate chapter, starting with historical and actual theoretical background, continued by our experimental results and concluded by spectral line lists with assigned notation.
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Affiliation(s)
- Svatopluk Civiš
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague 8, Czech Republic
| | - Adam Pastorek
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA
| | - Martin Ferus
- J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 18200 Prague 8, Czech Republic
| | - Sergei N Yurchenko
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
| | - Noor-Ines Boudjema
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
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4
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Herrick RR, Hensley S. Surface changes observed on a Venusian volcano during the Magellan mission. Science 2023; 379:1205-1208. [PMID: 36921020 DOI: 10.1126/science.abm7735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
Venus has a geologically young surface, but it is unknown whether it has ongoing active volcanism. From 1990 to 1992, the Magellan spacecraft imaged the planet's surface, using synthetic aperture radar. We examined volcanic areas on Venus that were imaged two or three times by Magellan and identified an ~2.2-square-kilometer volcanic vent that changed shape in the 8-month interval between two radar images. Additional volcanic flows downhill from the vent are visible in the second-epoch images, although we cannot rule out that they were present but invisible in the first epoch because of differences in imaging geometry. We interpret these results as evidence of ongoing volcanic activity on Venus.
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Affiliation(s)
- Robert R Herrick
- Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Scott Hensley
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
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Way MJ, Ostberg C, Foley BJ, Gillmann C, Höning D, Lammer H, O’Rourke J, Persson M, Plesa AC, Salvador A, Scherf M, Weller M. Synergies Between Venus & Exoplanetary Observations: Venus and Its Extrasolar Siblings. SPACE SCIENCE REVIEWS 2023; 219:13. [PMID: 36785654 PMCID: PMC9911515 DOI: 10.1007/s11214-023-00953-3] [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: 04/13/2022] [Accepted: 01/11/2023] [Indexed: 06/18/2023]
Abstract
Here we examine how our knowledge of present day Venus can inform terrestrial exoplanetary science and how exoplanetary science can inform our study of Venus. In a superficial way the contrasts in knowledge appear stark. We have been looking at Venus for millennia and studying it via telescopic observations for centuries. Spacecraft observations began with Mariner 2 in 1962 when we confirmed that Venus was a hothouse planet, rather than the tropical paradise science fiction pictured. As long as our level of exploration and understanding of Venus remains far below that of Mars, major questions will endure. On the other hand, exoplanetary science has grown leaps and bounds since the discovery of Pegasus 51b in 1995, not too long after the golden years of Venus spacecraft missions came to an end with the Magellan Mission in 1994. Multi-million to billion dollar/euro exoplanet focused spacecraft missions such as JWST, and its successors will be flown in the coming decades. At the same time, excitement about Venus exploration is blooming again with a number of confirmed and proposed missions in the coming decades from India, Russia, Japan, the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA). Here we review what is known and what we may discover tomorrow in complementary studies of Venus and its exoplanetary cousins.
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Affiliation(s)
- M. J. Way
- NASA Goddard Institute for Space Studies, 2880 Broadway, New York, NY 10025 USA
- Theoretical Astrophysics, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Colby Ostberg
- Department of Earth and Planetary Sciences, University of California, Riverside, CA 92521 USA
| | - Bradford J. Foley
- Department of Geosciences, Pennsylvania State University, University Park, PA USA
| | - Cedric Gillmann
- Department of Earth, Environmental and Planetary Sciences, Rice University, Houston, TX 77005 USA
| | - Dennis Höning
- Potsdam Institute for Climate Impact Research, Potsdam, Germany
- Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Helmut Lammer
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8042 Graz, Austria
| | - Joseph O’Rourke
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ USA
| | - Moa Persson
- Institut de Recherche en Astrophysique et Planétologie, Centre National de la Recherche Scientifique, Université Paul Sabatier – Toulouse III, Centre National d’Etudes Spatiales, Toulouse, France
| | | | - Arnaud Salvador
- Department of Astronomy and Planetary Science, Northern Arizona University, Box 6010, Flagstaff, AZ 86011 USA
- Habitability, Atmospheres, and Biosignatures Laboratory, University of Arizona, Tucson, AZ USA
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ USA
| | - Manuel Scherf
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstr. 6, 8042 Graz, Austria
- Institute of Physics, University of Graz, Graz, Austria
- Institute for Geodesy, Technical University, Graz, Austria
| | - Matthew Weller
- Lunar and Planetary Institute, 3600 Bay Area Blvd., Houston, TX 77058 USA
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The formation of tonalitic and granodioritic melt from Venusian basalt. Sci Rep 2022; 12:1652. [PMID: 35102296 PMCID: PMC8803830 DOI: 10.1038/s41598-022-05745-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/17/2022] [Indexed: 11/09/2022] Open
Abstract
The crust of Venus is composed of the low lying volcanic planitiae and the elevated, deformed tesserae. It is thought that the tesserae may be composed of silicic igneous rocks and that it may resemble proto-continental crust. The initial development of terrestrial continental crust is likely due to melting and deformation of primitive mafic crust via mantle-plume upwelling and collisional plate processes. Unlike Earth, the lithosphere of Venus is not divided into plates and therefore evolved continental crust, if present, developed primarily by melting of pre-existing mafic crust. Here, we report the results of high pressure equilibrium partial melting experiments using a parental composition similar to the basalt measured at the Venera 14 landing site in order to determine if silicic melts can be generated. It was found that at pressures of 1.5 GPa and 2.0 GPa and temperatures of 1080 °C, 1090 °C, and 1285 °C that tonalitic and granodioritic melts can be generated. The experimental results indicate that silicic rocks may be able to form in the crust of Venus providing the thermal regime is suitable and that the lower crust is basaltic. The implication is that the older, thicker regions of Venusian crust may be partially composed of silicic igneous rocks.
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Abstract
The initial reports of the presence of phosphine in the cloud decks of Venus have led to the suggestion that volcanism is the source of phosphine, through volcanic phosphides ejected into the clouds. Here, we examine the idea that mantle plume volcanism, bringing material from the deep mantle to the surface, could generate observed amounts of phosphine through the interaction of explosively erupted phosphide with sulfuric acid clouds. The direct eruption of deep mantle phosphide is unphysical, but a shallower material could contain traces of phosphide, and could be erupted to the surface. The explosive eruption that efficiently transports material to the clouds would require ocean:magma interactions or the subduction of a hydrated oceanic crust, neither of which occur on modern Venus. The transport of the erupted material to altitudes coinciding with the observations of phosphine is consequently very inefficient. Using the model proposed by Truong and Lunine as a base case, we estimate that an eruption volume of at least 21,600 km3/year would be required to explain the presence of 1 ppb phosphine in the clouds. This is greater than any historical terrestrial eruption rate, and would have several detectable consequences for remote and in situ observations to confirm. More realistic lithospheric mineralogy, volcano mechanics or atmospheric photochemistry require even more volcanism.
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8
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Davila AF. Life on Mars: Independent Genesis or Common Ancestor? ASTROBIOLOGY 2021; 21:802-812. [PMID: 33848439 DOI: 10.1089/ast.2020.2397] [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: 06/12/2023]
Abstract
The possibility of biological transfer between planetary bodies is seldom factored into life detection strategies, although the actuality of such an event would have profound implications for how we interpret potential biosignatures found on other worlds. This article addresses the possibility of life on Mars in the context of a biological transfer and an independent genesis of life. The phylogenetic tree of life on Earth is used as a blueprint to interpret evidence of life and as a guideline to determine the likelihood that potential biosignatures could be expressed by martian organisms. Several transfer scenarios are considered, depending on the timing of transfer with respect to the evolution of life on Earth. The implications of each transfer scenario and an independent genesis of life on the biochemical nature of the resulting martian organisms are discussed. The analysis highlights how conceding the possibility of a biological transfer has practical implications for how we search for evidence of life, both in terms of the quality of potential biosignatures and the likelihood that certain biosignatures might be expressed. It is concluded that a degree of uncertainty on the origin of martian organisms might be unavoidable, particularly in the absence of a biochemical context.
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Affiliation(s)
- Alfonso F Davila
- NASA Ames Research Center, Exobiology Branch, Moffett Field, California, USA
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9
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Brossier J, Gilmore MS, Toner K, Stein AJ. Distinct Mineralogy and Age of Individual Lava Flows in Atla Regio, Venus Derived From Magellan Radar Emissivity. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2021; 126:e2020JE006722. [PMID: 33959469 PMCID: PMC8098063 DOI: 10.1029/2020je006722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 02/18/2021] [Indexed: 06/12/2023]
Abstract
NASA's Magellan mission revealed that many Venus highlands exhibit low radar emissivity values at higher altitudes. This phenomenon is ascribed to the presence of minerals having high dielectric constants, produced or stabilized by temperature-dependent chemical weathering between the rocks and the atmosphere. Some large volcanoes on Venus have multiple reductions of radar emissivity at varying altitudes. The authors present morphological maps of major lava flow units at Maat, Ozza, and Sapas montes and compare them to radar emissivity. Sapas has a single reduction in emissivity values at 6,054.6 km, while Maat and Ozza have several reductions at altitudes of 6,052.5-6,056.7 km. Emissivity values are highly spatially correlated to individual lava flows indicating that minerals in the rocks control the emissivity signature. The emissivity patterns at these volcanoes require at least four individual ferroelectric mineral compositions in the rocks that are highly conductive at Curie temperatures of 693-731 K. These temperatures are compatible with chlorapatite and some perovskite oxides. Modeling the minimum volumes of ferroelectrics (10-100s ppm) shows the volume and type of ferroelectric may vary over the lifetime of a single volcano. The modeled volumes of ferroelectrics in Ozza and Sapas are greater than in Maat, consistent with the production of ferroelectrics via weathering over a longer period of time, and supporting the idea that Maat has younger volcanic activity. The stratigraphic relationship of Maat's youngest flows with impact craters may indicate the timeframe of the production of specific ferroelectrics via chemical weathering is over 9-60 Ma.
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Affiliation(s)
- J. Brossier
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, Middletown, CT, USA
| | - M. S. Gilmore
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, Middletown, CT, USA
| | - K. Toner
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, Middletown, CT, USA
| | - A. J. Stein
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, Middletown, CT, USA
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Brossier J, Gilmore MS. Variations in the radiophysical properties of tesserae and mountain belts on Venus: Classification and mineralogical trends. ICARUS 2021; 355:114161. [PMID: 33688099 PMCID: PMC7939048 DOI: 10.1016/j.icarus.2020.114161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Numerous studies show that major Venus highlands display anomalously high radar reflectivity and low radar emissivity relative to the planetary average. This is thought to be the result of the formation of minerals having high dielectric constants via weathering reactions occurring between the surface and the deep atmosphere in these elevated terrains, where temperatures are lower. These reactions are a function of rock composition, atmospheric composition, and degree of weathering, or age. Here, we examine the Magellan radar emissivity, altimetry and backscatter data for all mapped tesserae and mountain belts on Venus. We characterize and classify each contiguous highland according to its pattern of the variation of radar emissivity with increasing altitude. The highlands can be assigned to 7 distinct patterns of emissivity that correspond to at least 2 discrete types of mineralogy based on the altitude (and temperature) of the emissivity changes from the global average (excursions). The majority of the emissivity changes occur at altitudes above 6053 km (temperature below 726 K). The emissivity signature of the major tesserae of Aphrodite Terra, Beta Regio and Phoebe Regio are consistent with the presence of ferroelectric minerals in their rocks (Curie temperatures of ~700-720 K). Fortuna tesserae and the mountains belts (Maxwell, Freyja, Akna and Danu montes) in Ishtar Terra are consistent with the presence of semiconductor minerals. Some tesserae in Ishtar Terra (Clotho, Itzpapatotl and Jyestha tesserae) lie at altitudes over 6055 but lack the emissivity excursions seen in Fortuna tesserae and the mountains at same altitudes and thus may represent a third type of tessera composition. Finally, the spatial distribution of radar emissivity classes correlates to different geologic settings which may reflect differences in the mantle dynamics. Alternatively, this variability could be ascribed to changes in the atmospheric conditions.
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Affiliation(s)
- Jeremy Brossier
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, 265 Church St., Middletown, CT 06459, USA
| | - Martha S. Gilmore
- Department of Earth and Environmental Sciences, Planetary Sciences Group, Wesleyan University, 265 Church St., Middletown, CT 06459, USA
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López I, Hansen VL. Geologic Map of the Niobe Planitia Region (I-2467), Venus. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2020; 7:e2020EA001171. [PMID: 33134436 PMCID: PMC7583383 DOI: 10.1029/2020ea001171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
We present a 1:10M scale geologic map of the Niobe Planitia region of Venus (0°N-57°N/60°E-180°E). We herein refer to this area as the Niobe Map Area (NMA). Geologic mapping employed NASA Magellan synthetic aperture radar and altimetry data. The NMA geologic map and its companion Aphrodite Map Area (AMA) cover ~25% of Venus' surface, providing an important and unique perspective to study global and regional geologic processes. Both areas display a regional coherence of preserved geologic patterns that record three sequential geologic eras: the ancient era, the Artemis superstructure era, and the youngest fracture zone era. The NMA preserves a limited record of the fracture zone era, contrary to the AMA. However, the NMA hosts a diverse and rich assemblage of material and structures of the ancient era and structures that define the Artemis superstructure era. These two eras likely overlap in time and account for the formation of basement materials and lower plain units. Impact craters formed throughout the NMA recorded history. Approximately 40% of the impact craters show interior flood deposits, indicating that a significant number of NMA impact craters experienced notable geological events after impact crater formation. This and other geologic relations record a geohistory inconsistent with postulated global catastrophic resurfacing. Together, the NMA and the AMA record a rich geologic history of the surface of Venus that provide a framework to formulate new working hypotheses of Venus evolution and to plan future studies of the planet.
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Affiliation(s)
- Iván López
- Departamento de Biología y Geología, Física y Química InorgánicaUniversidad Rey Juan CarlosMadridSpain
| | - Vicki L. Hansen
- Department of Earth and Environmental SciencesUniversity of Minnesota‐DuluthDuluthMNUSA
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12
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Hansen VL, López I. Geologic Map of Aphrodite Map Area (AMA; I-2476), Venus. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2020; 7:e2019EA001066. [PMID: 33134435 PMCID: PMC7583386 DOI: 10.1029/2019ea001066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 06/08/2020] [Accepted: 06/13/2020] [Indexed: 06/11/2023]
Abstract
We present a 1:10-M-scale geologic map of the Aphrodite Map Area (AMA) of Venus (0°N-57°S/60-80°E). Geologic mapping employed NASA Magellan synthetic aperture radar and altimetry data. The AMA geologic map, with detailed structural elements and geologic units covering over one eighth of Venus' surface, affords an important and unique perspective to test models of global-scale geologic processes through time. Geologic relations record a history inconsistent with global catastrophic resurfacing. The AMA displays a regional coherence of preserved geologic patterns that record three sequential geologic eras: the ancient era, the Artemis superstructure era, and the youngest fracture zone era. The ancient era and Artemis superstructure, with a footprint covering more than 25% of the surface, are recorded in the Niobe Map Area to the north. The latter two eras likely overlap in time. The fracture zone domain, part of a globally extensive province, marks the most spatially focused tectonomagmatic domain within the AMA. Impact craters are both cut by and overprint fracture zone structures. Twelve percent of AMA impact craters that occur within the fracture zone domain predate or formed during fracture zone development. This observation indicates the relative youth of the fracture zone era and is consistent with the possibility that this domain remains geologically active. The AMA records a rich geologic history of large tract of the surface of Venus and provides an important framework to formulate new working hypotheses of Venus evolution and contribute to planning future studies of the surface of planets.
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Affiliation(s)
- V. L. Hansen
- Department of Earth and Environmental SciencesUniversity of Minnesota, DuluthDuluthMNUSA
| | - I. López
- Department of Biology and Geology, Physics and Inorganic Chemistry, Área de GeologíaUniversidad Rey Juan CarlosMóstoles, MadridSpain
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13
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Brossier J, Gilmore M, Toner K. Low radar emissivity signatures on Venus volcanoes and coronae: New insights on relative composition and age. ICARUS 2020; 343:113693. [PMID: 33678821 PMCID: PMC7934947 DOI: 10.1016/j.icarus.2020.113693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Multiple studies reveal that most of Venus highlands exhibit anomalously high radar reflectivity and low radar emissivity relative to the lowlands. This phenomenon is thought to be the result of atmosphere-surface interactions in the highlands, due to lower temperatures. These reactions are a function of rock composition, atmospheric composition, and degree of weathering. We examine the Magellan radar emissivity, altimetry and SAR data for all major volcanoes and coronae on Venus. We characterize and classify edifices according to the pattern of the variation of radar emissivity with altitude. The volcanic highlands can be classified into 7 distinct patterns of emissivity that correspond to at least 3 discrete types of mineralogy based on the altitude (temperature) of the emissivity anomalies. The majority of emissivity anomalies support the hypothesis of a weathering phenomenon at high altitude (>6053 km), but we also find strong emissivity anomalies at lower altitudes that correspond spatially to individual lava flows, indicating variations in mineralogy within an evolving volcanic system. The emissivity signature of tallest volcanoes on Venus are consistent with the presence of ferroelectric minerals in their rocks, while volcanic edifices in western Ishtar Terra and eastern Aphrodite Terra are consistent with the presence of semiconductor minerals. Sapas Mons and Pavlova Corona are also consistent with ferroelectrics, but at a different Curie temperature than the other volcanoes in Atla Regio. The spatial distribution of radar emissivity classes correlates to different geologic settings indicating that different mantle source regions (deep/shallow plumes, and possible convergence zones) may contribute to differences in mineralogy for the studied edifices. Finally, we show that the emissivity signatures of Idunn, Maat and other volcanic edifices are consistent with relatively fresh and unweathered rocks, indicating recent or possibly current volcanism on Venus.
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14
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Hansen VL. Global tectonic evolution of Venus, from exogenic to endogenic over time, and implications for early Earth processes. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2018; 376:rsta.2017.0412. [PMID: 30275161 DOI: 10.1098/rsta.2017.0412] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/04/2018] [Indexed: 06/08/2023]
Abstract
Venus provides a rich arena in which to stretch one's tectonic imagination with respect to non-plate tectonic processes of heat transfer on an Earth-like planet. Venus is similar to Earth in density, size, inferred composition and heat budget. However, Venus' lack of plate tectonics and terrestrial surficial processes results in the preservation of a unique surface geologic record of non-plate tectonomagmatic processes. In this paper, I explore three global tectonic domains that represent changes in global conditions and tectonic regimes through time, divided respectively into temporal eras. Impactors played a prominent role in the ancient era, characterized by thin global lithosphere. The Artemis superstructure era highlights sublithospheric flow processes related to a uniquely large super plume. The fracture zone complex era, marked by broad zones of tectonomagmatic activity, witnessed coupled spreading and underthrusting, since arrested. These three tectonic regimes provide possible analogue models for terrestrial Archaean craton formation, continent formation without plate tectonics, and mechanisms underlying the emergence of plate tectonics. A bolide impact model for craton formation addresses the apparent paradox of both undepleted mantle and growth of Archaean crust, and recycling of significant Archaean crust to the mantle.This article is part of a discussion meeting issue 'Earth dynamics and the development of plate tectonics'.
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Affiliation(s)
- Vicki L Hansen
- Department of Earth and Environmental Sciences, University of Minnesota Duluth, 1114 Kirby Drive, Duluth, MN 55812, USA
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Rozel AB, Golabek GJ, Jain C, Tackley PJ, Gerya T. Continental crust formation on early Earth controlled by intrusive magmatism. Nature 2017; 545:332-335. [PMID: 28482358 DOI: 10.1038/nature22042] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 02/21/2017] [Indexed: 11/09/2022]
Abstract
The global geodynamic regime of early Earth, which operated before the onset of plate tectonics, remains contentious. As geological and geochemical data suggest hotter Archean mantle temperature and more intense juvenile magmatism than in the present-day Earth, two crust-mantle interaction modes differing in melt eruption efficiency have been proposed: the Io-like heat-pipe tectonics regime dominated by volcanism and the "Plutonic squishy lid" tectonics regime governed by intrusive magmatism, which is thought to apply to the dynamics of Venus. Both tectonics regimes are capable of producing primordial tonalite-trondhjemite-granodiorite (TTG) continental crust but lithospheric geotherms and crust production rates as well as proportions of various TTG compositions differ greatly, which implies that the heat-pipe and Plutonic squishy lid hypotheses can be tested using natural data. Here we investigate the creation of primordial TTG-like continental crust using self-consistent numerical models of global thermochemical convection associated with magmatic processes. We show that the volcanism-dominated heat-pipe tectonics model results in cold crustal geotherms and is not able to produce Earth-like primordial continental crust. In contrast, the Plutonic squishy lid tectonics regime dominated by intrusive magmatism results in hotter crustal geotherms and is capable of reproducing the observed proportions of various TTG rocks. Using a systematic parameter study, we show that the typical modern eruption efficiency of less than 40 per cent leads to the production of the expected amounts of the three main primordial crustal compositions previously reported from field data (low-, medium- and high-pressure TTG). Our study thus suggests that the pre-plate-tectonics Archean Earth operated globally in the Plutonic squishy lid regime rather than in an Io-like heat-pipe regime.
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Affiliation(s)
- A B Rozel
- Institute of Geophysics, ETH Zurich, 8092 Zurich, Switzerland
| | - G J Golabek
- Bayerisches Geoinstitut, University of Bayreuth, 95440 Bayreuth, Germany
| | - C Jain
- Institute of Geophysics, ETH Zurich, 8092 Zurich, Switzerland
| | - P J Tackley
- Institute of Geophysics, ETH Zurich, 8092 Zurich, Switzerland
| | - T Gerya
- Institute of Geophysics, ETH Zurich, 8092 Zurich, Switzerland
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16
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Domagal-Goldman SD, Wright KE, Adamala K, Arina de la Rubia L, Bond J, Dartnell LR, Goldman AD, Lynch K, Naud ME, Paulino-Lima IG, Singer K, Walther-Antonio M, Abrevaya XC, Anderson R, Arney G, Atri D, Azúa-Bustos A, Bowman JS, Brazelton WJ, Brennecka GA, Carns R, Chopra A, Colangelo-Lillis J, Crockett CJ, DeMarines J, Frank EA, Frantz C, de la Fuente E, Galante D, Glass J, Gleeson D, Glein CR, Goldblatt C, Horak R, Horodyskyj L, Kaçar B, Kereszturi A, Knowles E, Mayeur P, McGlynn S, Miguel Y, Montgomery M, Neish C, Noack L, Rugheimer S, Stüeken EE, Tamez-Hidalgo P, Imari Walker S, Wong T. The Astrobiology Primer v2.0. ASTROBIOLOGY 2016; 16:561-653. [PMID: 27532777 PMCID: PMC5008114 DOI: 10.1089/ast.2015.1460] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 06/06/2016] [Indexed: 05/09/2023]
Affiliation(s)
- Shawn D Domagal-Goldman
- 1 NASA Goddard Space Flight Center , Greenbelt, Maryland, USA
- 2 Virtual Planetary Laboratory , Seattle, Washington, USA
| | - Katherine E Wright
- 3 University of Colorado at Boulder , Colorado, USA
- 4 Present address: UK Space Agency, UK
| | - Katarzyna Adamala
- 5 Department of Genetics, Cell Biology and Development, University of Minnesota , Minneapolis, Minnesota, USA
| | | | - Jade Bond
- 7 Department of Physics, University of New South Wales , Sydney, Australia
| | | | | | - Kennda Lynch
- 10 Division of Biological Sciences, University of Montana , Missoula, Montana, USA
| | - Marie-Eve Naud
- 11 Institute for research on exoplanets (iREx) , Université de Montréal, Montréal, Canada
| | - Ivan G Paulino-Lima
- 12 Universities Space Research Association , Mountain View, California, USA
- 13 Blue Marble Space Institute of Science , Seattle, Washington, USA
| | - Kelsi Singer
- 14 Southwest Research Institute , Boulder, Colorado, USA
| | | | - Ximena C Abrevaya
- 16 Instituto de Astronomía y Física del Espacio (IAFE) , UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina
| | - Rika Anderson
- 17 Department of Biology, Carleton College , Northfield, Minnesota, USA
| | - Giada Arney
- 18 University of Washington Astronomy Department and Astrobiology Program , Seattle, Washington, USA
| | - Dimitra Atri
- 13 Blue Marble Space Institute of Science , Seattle, Washington, USA
| | | | - Jeff S Bowman
- 19 Lamont-Doherty Earth Observatory, Columbia University , Palisades, New York, USA
| | | | | | - Regina Carns
- 22 Polar Science Center, Applied Physics Laboratory, University of Washington , Seattle, Washington, USA
| | - Aditya Chopra
- 23 Planetary Science Institute, Research School of Earth Sciences, Research School of Astronomy and Astrophysics, The Australian National University , Canberra, Australia
| | - Jesse Colangelo-Lillis
- 24 Earth and Planetary Science, McGill University , and the McGill Space Institute, Montréal, Canada
| | | | - Julia DeMarines
- 13 Blue Marble Space Institute of Science , Seattle, Washington, USA
| | | | - Carie Frantz
- 27 Department of Geosciences, Weber State University , Ogden, Utah, USA
| | - Eduardo de la Fuente
- 28 IAM-Departamento de Fisica, CUCEI , Universidad de Guadalajara, Guadalajara, México
| | - Douglas Galante
- 29 Brazilian Synchrotron Light Laboratory , Campinas, Brazil
| | - Jennifer Glass
- 30 School of Earth and Atmospheric Sciences, Georgia Institute of Technology , Atlanta, Georgia , USA
| | | | | | - Colin Goldblatt
- 33 School of Earth and Ocean Sciences, University of Victoria , Victoria, Canada
| | - Rachel Horak
- 34 American Society for Microbiology , Washington, DC, USA
| | | | - Betül Kaçar
- 36 Harvard University , Organismic and Evolutionary Biology, Cambridge, Massachusetts, USA
| | - Akos Kereszturi
- 37 Research Centre for Astronomy and Earth Sciences , Hungarian Academy of Sciences, Budapest, Hungary
| | - Emily Knowles
- 38 Johnson & Wales University , Denver, Colorado, USA
| | - Paul Mayeur
- 39 Rensselaer Polytechnic Institute , Troy, New York, USA
| | - Shawn McGlynn
- 40 Earth Life Science Institute, Tokyo Institute of Technology , Tokyo, Japan
| | - Yamila Miguel
- 41 Laboratoire Lagrange, UMR 7293, Université Nice Sophia Antipolis , CNRS, Observatoire de la Côte d'Azur, Nice, France
| | | | - Catherine Neish
- 43 Department of Earth Sciences, The University of Western Ontario , London, Canada
| | - Lena Noack
- 44 Royal Observatory of Belgium , Brussels, Belgium
| | - Sarah Rugheimer
- 45 Department of Astronomy, Harvard University , Cambridge, Massachusetts, USA
- 46 University of St. Andrews , St. Andrews, UK
| | - Eva E Stüeken
- 47 University of Washington , Seattle, Washington, USA
- 48 University of California , Riverside, California, USA
| | | | - Sara Imari Walker
- 13 Blue Marble Space Institute of Science , Seattle, Washington, USA
- 50 School of Earth and Space Exploration and Beyond Center for Fundamental Concepts in Science, Arizona State University , Tempe, Arizona, USA
| | - Teresa Wong
- 51 Department of Earth and Planetary Sciences, Washington University in St. Louis , St. Louis, Missouri, USA
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Platz T, Byrne PK, Massironi M, Hiesinger H. Volcanism and tectonism across the inner solar system: an overview. ACTA ACUST UNITED AC 2014. [DOI: 10.1144/sp401.22] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractVolcanism and tectonism are the dominant endogenic means by which planetary surfaces change. This book, in general, and this overview, in particular, aim to encompass the broad range in character of volcanism, tectonism, faulting and associated interactions observed on planetary bodies across the inner solar system – a region that includes Mercury, Venus, Earth, the Moon, Mars and asteroids. The diversity and breadth of landforms produced by volcanic and tectonic processes are enormous, and vary across the inventory of inner solar system bodies. As a result, the selection of prevailing landforms and their underlying formational processes that are described and highlighted in this review are but a primer to the expansive field of planetary volcanism and tectonism. In addition to this extended introductory contribution, this Special Publication features 21 dedicated research articles about volcanic and tectonic processes manifest across the inner solar system. Those articles are summarized at the end of this review.
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Affiliation(s)
- T. Platz
- Planetary Science Institute, 1700 East Fort Lowell Road, Tucson, AZ 85719-2395, USA
- Freie Universität Berlin, Institute of Geological Sciences, Planetary Sciences & Remote Sensing, Malteserstrasse 74-100, 12249 Berlin, Germany
| | - P. K. Byrne
- Lunar and Planetary Institute, Universities Space Research Association, 3600 Bay Area Boulevard, Houston, TX 77058, USA
- Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015-1305, USA
| | - M. Massironi
- Dipartimento di Geoscienze, Universita' degli Studi di Padova, via G. Gradenigo 6, 35131 Padova, Italy
| | - H. Hiesinger
- Institut für Planetologie, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Strasse 10, 48149 Münster, Germany
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18
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Harris LB, Bédard JH. Interactions between continent-like ‘drift’, rifting and mantle flow on Venus: gravity interpretations and Earth analogues. ACTA ACUST UNITED AC 2014. [DOI: 10.1144/sp401.9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractRegional shear zones are interpreted from Bouguer gravity data over northern polar to low southern latitudes of Venus. Offset and deflection of horizontal gravity gradient edges (‘worms’) and lineaments interpreted from displacement of Bouguer anomalies portray crustal structures, the geometry of which resembles both regional transcurrent shear zones bounding or cross-cutting cratons and fracture zones in oceanic crust on Earth. High Bouguer anomalies and thinned crust comparable to the Mid-Continent Rift in North America suggest underplating of denser, mantle-derived mafic material beneath extended crust in Sedna and Guinevere planitia on Venus. These rifts are partitioned by transfer faults and flank a zone of mantle upwelling (Eistla Regio) between colinear hot, upwelling mantle plumes. Data support the northward drift and indentation of Lakshmi Planum in western Ishtar Terra and >1000 km of transcurrent displacement between Ovda and Thetis regiones. Large displacements of areas of continent-like crust on Venus are interpreted to result from mantle tractions and pressure acting against their deep lithospheric mantle ‘keels’ commensurate with extension in adjacent rifts. Displacements of Lakshmi Planum and Ovda and Thetis regiones on Venus, a planet without plate tectonics, cannot be attributed to plate boundary forces (i.e. ridge push and slab pull). Results therefore suggest that a similar, subduction-free geodynamic model may explain deformation features in Archaean greenstone terrains on Earth. Continent-like ‘drift’ on Venus also resembles models for the late Cenozoic–Recent Earth, where westward translation of the Americas and northward displacement of India are interpreted as being driven by mantle flow tractions on the keels of their Precambrian cratons.Supplementary material:Bouguer gravity and topographic images over a segment of the Mid-Atlantic ridge and Ross Island and surrounds in Antarctica, principal horizontal stress trajectories about mantle plumes on Earth, map and interactive 3D representations of cratonic keels beneath North America from seismic tomography, and a centrifuge simulation for comparison with Venus in support of our tectonic model are available at http://www.geolsoc.org.uk/SUP18736.
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Affiliation(s)
- Lyal B. Harris
- Institut national de la recherche scientifique, Centre – Eau Terre Environnement (INRS-ETE), 490 de la Couronne, Québec, Canada QC G1K 9A9
| | - Jean H. Bédard
- Geological Survey of Canada, 490 de la Couronne, Québec, Canada QC G1K 9A9
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19
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Head JW, Coffin MF. Large Igneous Provinces: A Planetary Perspective. ACTA ACUST UNITED AC 2013. [DOI: 10.1029/gm100p0411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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21
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Herrick RR, Rumpf ME. Postimpact modification by volcanic or tectonic processes as the rule, not the exception, for Venusian craters. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010je003722] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Smrekar SE, Stofan ER, Mueller N, Treiman A, Elkins-Tanton L, Helbert J, Piccioni G, Drossart P. Recent hotspot volcanism on Venus from VIRTIS emissivity data. Science 2010; 328:605-8. [PMID: 20378775 DOI: 10.1126/science.1186785] [Citation(s) in RCA: 190] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The questions of whether Venus is geologically active and how the planet has resurfaced over the past billion years have major implications for interior dynamics and climate change. Nine "hotspots"--areas analogous to Hawaii, with volcanism, broad topographic rises, and large positive gravity anomalies suggesting mantle plumes at depth--have been identified as possibly active. This study used variations in the thermal emissivity of the surface observed by the Visible and Infrared Thermal Imaging Spectrometer on the European Space Agency's Venus Express spacecraft to identify compositional differences in lava flows at three hotspots. The anomalies are interpreted as a lack of surface weathering. We estimate the flows to be younger than 2.5 million years and probably much younger, about 250,000 years or less, indicating that Venus is actively resurfacing.
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Affiliation(s)
- Suzanne E Smrekar
- Jet Propulsion Laboratory, Mail Stop 183-501, 4800 Oak Grove Drive, Pasadena, CA 91109, USA.
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25
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Early formation of evolved asteroidal crust. Nature 2009; 457:179-82. [PMID: 19129845 DOI: 10.1038/nature07651] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Accepted: 11/17/2008] [Indexed: 11/08/2022]
Abstract
Mechanisms for the formation of crust on planetary bodies remain poorly understood. It is generally accepted that Earth's andesitic continental crust is the product of plate tectonics, whereas the Moon acquired its feldspar-rich crust by way of plagioclase flotation in a magma ocean. Basaltic meteorites provide evidence that, like the terrestrial planets, some asteroids generated crust and underwent large-scale differentiation processes. Until now, however, no evolved felsic asteroidal crust has been sampled or observed. Here we report age and compositional data for the newly discovered, paired and differentiated meteorites Graves Nunatak (GRA) 06128 and GRA 06129. These meteorites are feldspar-rich, with andesite bulk compositions. Their age of 4.52 +/- 0.06 Gyr demonstrates formation early in Solar System history. The isotopic and elemental compositions, degree of metamorphic re-equilibration and sulphide-rich nature of the meteorites are most consistent with an origin as partial melts from a volatile-rich, oxidized asteroid. GRA 06128 and 06129 are the result of a newly recognized style of evolved crust formation, bearing witness to incomplete differentiation of their parent asteroid and to previously unrecognized diversity of early-formed materials in the Solar System.
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Mueller N, Helbert J, Hashimoto GL, Tsang CCC, Erard S, Piccioni G, Drossart P. Venus surface thermal emission at 1μm in VIRTIS imaging observations: Evidence for variation of crust and mantle differentiation conditions. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008je003118] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Stern RJ. When and how did plate tectonics begin? Theoretical and empirical considerations. ACTA ACUST UNITED AC 2007. [DOI: 10.1007/s11434-007-0073-8] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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28
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Basilevsky AT, Head JW. Impact craters on regional plains on Venus: Age relations with wrinkle ridges and implications for the geological evolution of Venus. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002473] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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29
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Schulze-Makuch D, Dohm JM, Fairén AG, Baker VR, Fink W, Strom RG. Venus, Mars, and the ices on Mercury and the moon: astrobiological implications and proposed mission designs. ASTROBIOLOGY 2005; 5:778-95. [PMID: 16379531 DOI: 10.1089/ast.2005.5.778] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Venus and Mars likely had liquid water bodies on their surface early in the Solar System history. The surfaces of Venus and Mars are presently not a suitable habitat for life, but reservoirs of liquid water remain in the atmosphere of Venus and the subsurface of Mars, and with it also the possibility of microbial life. Microbial organisms may have adapted to live in these ecological niches by the evolutionary force of directional selection. Missions to our neighboring planets should therefore be planned to explore these potentially life-containing refuges and return samples for analysis. Sample return missions should also include ice samples from Mercury and the Moon, which may contain information about the biogenic material that catalyzed the early evolution of life on Earth (or elsewhere). To obtain such information, science-driven exploration is necessary through varying degrees of mission operation autonomy. A hierarchical mission design is envisioned that includes spaceborne (orbital), atmosphere (airborne), surface (mobile such as rover and stationary such as lander or sensor), and subsurface (e.g., ground-penetrating radar, drilling, etc.) agents working in concert to allow for sufficient mission safety and redundancy, to perform extensive and challenging reconnaissance, and to lead to a thorough search for evidence of life and habitability.
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Strom RG, Malhotra R, Ito T, Yoshida F, Kring DA. The origin of planetary impactors in the inner solar system. Science 2005; 309:1847-50. [PMID: 16166515 DOI: 10.1126/science.1113544] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Insights into the history of the inner solar system can be derived from the impact cratering record of the Moon, Mars, Venus, and Mercury and from the size distributions of asteroid populations. Old craters from a unique period of heavy bombardment that ended approximately 3.8 billion years ago were made by asteroids that were dynamically ejected from the main asteroid belt, possibly due to the orbital migration of the giant planets. The impactors of the past approximately 3.8 billion years have a size distribution quite different from that of the main belt asteroids but very similar to that of near-Earth asteroids.
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Affiliation(s)
- Robert G Strom
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
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Affiliation(s)
- A.C Fowler
- Mathematical Institute, 24–29 St Giles', Oxford OX1 3LB, UK
| | - B.G O'Brien
- Department of Mathematics, University of Limerick, Limerick, Republic of Ireland
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33
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Johnson CL. A conceptual model for the relationship between coronae and large-scale mantle dynamics on Venus. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001962] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Ivanov MA, Head JW. Geology of Venus: Mapping of a global geotraverse at 30°N latitude. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001265] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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38
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Herrick RR, Sharpton VL. Implications from stereo-derived topography of Venusian impact craters. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001225] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Hansen VL, Phillips RJ, Willis JJ, Ghent RR. Structures in tessera terrain, Venus: Issues and answers. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001137] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Collins GC, Head JW, Basilevsky AT, Ivanov MA. Evidence for rapid regional plains emplacement on Venus from the population of volcanically embayed impact craters. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001041] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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41
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Abstract
Tectonics, volcanism, and climate on Venus may be strongly coupled. Large excursions in surface temperature predicted to follow a global or near-global volcanic event diffuse into the interior and introduce thermal stresses of a magnitude sufficient to influence widespread tectonic deformation. This sequence of events accounts for the timing and many of the characteristics of deformation in the ridged plains of Venus, the most widely preserved volcanic terrain on the planet.
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Affiliation(s)
- S C Solomon
- Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015, USA
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42
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Wichman RW. Internal crater modification on Venus: Recognizing crater-centered volcanism by changes in floor morphometry and floor brightness. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1997je000428] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Kreslavsky MA, Head JW. Morphometry of small shield volcanoes on Venus: Implications for the thickness of regional plains. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999je001042] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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44
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Gilmore MS, Collins GC, Ivanov MA, Marinangeli L, Head JW. Style and sequence of extensional structures in tessera terrain, Venus. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01322] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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45
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Hauck SA, Phillips RJ, Price MH. Venus: Crater distribution and plains resurfacing models. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je00400] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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McGovern PJ, Solomon SC. Growth of large volcanoes on Venus: Mechanical models and implications for structural evolution. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je01046] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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47
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Williams-Jones G, Williams-Jones AE, Stix J. The nature and origin of Venusian canali. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je00243] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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48
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Affiliation(s)
- Roger J. Phillips
- R. J. Phillips is in the Department of Earth and Planetary Sciences, Washington University, Campus Box 1169, One Brookings Drive, St. Louis, MO 63130, USA. V. L. Hansen is in the Department of Geological Sciences, Southern Methodist University, Dallas, TX 75275, USA
| | - Vicki L. Hansen
- R. J. Phillips is in the Department of Earth and Planetary Sciences, Washington University, Campus Box 1169, One Brookings Drive, St. Louis, MO 63130, USA. V. L. Hansen is in the Department of Geological Sciences, Southern Methodist University, Dallas, TX 75275, USA
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McGill GE. Central Eistla Regio: Origin and relative age of topographic rise. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98je00229] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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