Tectonic Interpretations of Central Ishtar Terra (Venus) from and Magellan Full-Resolution Radar Images
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Round 3 Michael Etzkorn • Brad Fischer • Clare Keenan • Mike Laudermith • Lauren Onel Noah Prince • Jacob Simmons • Kristin Strey • Tyler Vaughan
2017 SCOP MS 8 Round 3 Michael Etzkorn • Brad Fischer • Clare Keenan • Mike Laudermith • Lauren Onel Noah Prince • Jacob Simmons • Kristin Strey • Tyler Vaughan Tossups (1) This astronomical body, which was called Hesperus when it appeared as the Evening Star, has surface features called Maxwell Montes, Lakshmi Planum, and Ishtar Terra that are obscured by a permanent cover of (*) sulfuric acid clouds. A 96% carbon dioxide atmosphere led to a runaway greenhouse effect on, for ten points, what second planet in the Solar System? ANSWER: Venus (2) A holder of this title controversially pushed his people away from polytheism in favor of a solar god worshiped at Amarna. Lord Carnavon funded Howard Carter’s 1922 expedition to discover the burial grounds of one of these people at (*) Luxor, and found a sarcophagus containing a solid gold funerary mask and mummified remains. For ten points, name this title given to Akenhaten, King Tut, and other ancient Egyptian rulers. ANSWER: Egyptian pharaohs (3) A composer from this country wrote about the unlucky servant Ninetta in The Thieving Magpie, and included a “cavalry charge” galop in his (*) William Tell overture. For ten points, name this home country of Gioachino Rossini as well as Giacomo Puccini, who set his opera Tosca in Rome. ANSWER: Italy (accept Italia; accept Italian Republic or Repubblica italiana) (4) The Rydberg formula inspired one model of these objects, and the first sub-parts of these objects were detected by a deflection of cathode rays observed by JJ Thomson. A (*) gold foil experiment determined that these things possess a dense central mass, disproving their “plum pudding” model. -
Investigating Mineral Stability Under Venus Conditions: a Focus on the Venus Radar Anomalies Erika Kohler University of Arkansas, Fayetteville
University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 5-2016 Investigating Mineral Stability under Venus Conditions: A Focus on the Venus Radar Anomalies Erika Kohler University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Geochemistry Commons, Mineral Physics Commons, and the The unS and the Solar System Commons Recommended Citation Kohler, Erika, "Investigating Mineral Stability under Venus Conditions: A Focus on the Venus Radar Anomalies" (2016). Theses and Dissertations. 1473. http://scholarworks.uark.edu/etd/1473 This Dissertation is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Investigating Mineral Stability under Venus Conditions: A Focus on the Venus Radar Anomalies A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Space and Planetary Sciences by Erika Kohler University of Oklahoma Bachelors of Science in Meteorology, 2010 May 2016 University of Arkansas This dissertation is approved for recommendation to the Graduate Council. ____________________________ Dr. Claud H. Sandberg Lacy Dissertation Director Committee Co-Chair ____________________________ ___________________________ Dr. Vincent Chevrier Dr. Larry Roe Committee Co-chair Committee Member ____________________________ ___________________________ Dr. John Dixon Dr. Richard Ulrich Committee Member Committee Member Abstract Radar studies of the surface of Venus have identified regions with high radar reflectivity concentrated in the Venusian highlands: between 2.5 and 4.75 km above a planetary radius of 6051 km, though it varies with latitude. -
Cleopatra Crater on Venus: Happy Solution of the Volcanic Vs
CLEOPATRA CRATER ON VENUS: HAPPY SOLUTION OF THE VOLCANIC VS. IMPACT CRATER CONTROVERSY; A.T. Basilevsky, A.T. Vernadsky Institute of Geochemistry and Analytical chemistry, Moscow, USSR, and G.G. Schaber, U.S. Geological Survey, Flagstaff AZ 86001 ~ntroduction. Cleopatra is a 100-km-diameter crater on the eastern slope of Maxwell Montes in western Ishtar Terra. For over 12 years, Cleopatra has been the subject of scientific controversy. Discovered during the Pioneer Venus altimetric survey, this feature was initially interpreted as a caldera near the top of a giant volcanic construct, Maxwell Montes [I]. Venera 15/16 data and recent Arecibo radar images show, however, that the Maxwell Montes appear to be more of a tectonic construct, with little or no resemblance to other giant shields known in the Solar System; thus, a nonvolcanic origin of Cleopatra was proposed [2-61. The similarity of the double-ring structure of Cleopatra to those of other multi-ring impact craters of similar size on Venus and the Moon, Mercury, and Mars was more recently given by Basilevsky and Ivanov [7] as the primarily reason to consider this feature an impact crater. At the same time, some characteristics of Cleopatra seemed to contradict an impact origin. For example, Schaber et al. [8], suggestingthat a definitive verification of a volcanic or impact origin would probably require Magellan data, proposed that the evidence from Venera 15/16 and earlier data for a probable volcanic origin for Cleopatra is substantial. They cited, among other points: (1) the absence of a raised rim and highly backscattering ejecta deposits; (2) the crater's association with plains-forming deposits immediately downslope to the east, interpreted as probable lava flows emanating from a distinct breach in the crater's rim; (3) the excessive depth (2.5 km) and depth-to-diameter ratio (0.028) of the crater, (4) the offset of the inner and outer craters; and (5) the crater's position in what was interpreted as a regional tectonic framework. -
Styles of Deformation in Ishtar Terra and Their Implications
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 97, NO. El0, PAGES 16,085-16,120, OCTOBER 25, 1992 Stylesof Deformationin IshtarTerra and Their Implications Wn.T.TAMM. KAU•A,• DOAN•L. BINDSCHAD•-R,l ROBERT E. GPaM•,2'3 VICKIL. HANSEN,2KARl M. ROBERTS,4AND SUZANNE E. SMREr,AR s IshtarTerra, the highest region on Venus, appears to havecharacteristics of both plume uplifts and convergent belts.Magellan imagery over longitudes 330ø-30øE indicates a great variety of tectonicand volcanic activity, with largevariations within distances of onlya few 100km. Themost prominent terrain types are the volcanic plains of Lakshmiand the mountain belts of Maxwell,Freyja, and Danu. Thebelts appear to havemarked variations in age. Thereare also extensive regions of tesserain boththe upland and outboard plateaus, some rather featureless smoothscarps, flanking basins of complexextensional tectonics, and regions of gravitationalor impactmodifica- tion.Parts of Ishtarare the locations of contemporaryvigorous tectonics and past extensive volcanism. Ishtar appearsto be the consequence of a history of several100 m.y., in whichthere have been marked changes in kinematic patternsand in whichactivity at any stage has been strongly influenced by the past. Ishtar demonstrates three general propertiesof Venus:(1) erosionaldegradation is absent,leading to preservationof patternsresulting from past activity;(2) manysurface features are the responses ofa competentlayer less than 10 km thick to flowsof 100km orbroaderscale; and (3) thesebroader scale flows are controlled mainly by heterogeneities inthe mantle. Ishtar Terra doesnot appear to bethe result of a compressionconveyed by anEarthlike lithosphere. But there is stilldoubt as to whetherIshtar is predominantlythe consequence of a mantleupflow or downflow.Upflow is favoredby the extensivevolcanic plain of Lakshmiand the high geoid: topography ratio; downflow is favoredby the intense deformationof themountain belts and the absence of majorrifts. -
Venus' Ishtar Terra: Topographic Analysis of Maxwell, Freyja, Akna
16th VEXAG Meeting 2018 (LPI Contrib. No. 2137) 8046.pdf Venus’ Ishtar Terra: Topographic Analysis of Maxwell, Freyja, Akna and Danu Montes. Sara Rastegar1 and 2 1 Donna M. Jurdy , C ity Colleges of Chicago, Harold Washington College, 30 E. Lake Street, Chicago, IL 60601, 2 [email protected], D epartment of Earth and Planetary Sciences, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, [email protected] Introduction: Venus’ mountain chains (Figure 1) Analysis: We attempt to address these questions surround Lakshmi Planum, a 3-4 km highland, making with analysis of Magellan topographic data for up Ishtar Terra. No other mountain belts exist on quantitative comparison of Venus' four mountain Venus. Circling Ishtar Terra, Maxwell Montes, ascends chains: Maxwell, Freyja, Akna and Danu. Patterns in to over 11 km, ranking as the location of highest topography may provide clues to the dynamics forming elevation on the planet. Freyja Montes rises to over 7 these Venusian orogenic belts. From topographic km, higher than Akna Montes at about an elevation of profiles across the ec mountain chain, we then 6 km. Danu Montes, ~1.5 km over Lakshmi Planum, determine an average profile for each mountain belt. alone displays a distinctly arcuate form. Next, we correlate these averages to establish a measure of similarity between the chains and terrestrial Tectonic Enigma: The existence of the four analogs. These correlations allow construction of a venusian mountain chains has been attributed to covariance matrix, which can be diagonalized for localized downwelling - analogous to terrestrial eigenvalues, for Principal Component Analysis (PCA) subduction - in response to the proposed upwelling [4]. -
Testing Evolutionary Models for Venus with the DAVINCI+ Mission
EPSC Abstracts Vol. 14, EPSC2020-534, 2020 https://doi.org/10.5194/epsc2020-534 Europlanet Science Congress 2020 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Venus, Earth's divergent twin?: Testing evolutionary models for Venus with the DAVINCI+ mission Walter S. Kiefer1, James Garvin2, Giada Arney2, Sushil Atreya3, Bruce Campbell4, Valeria Cottini2, Justin Filiberto1, Stephanie Getty2, Martha Gilmore5, David Grinspoon6, Noam Izenberg7, Natasha Johnson2, Ralph Lorenz7, Charles Malespin2, Michael Ravine8, Christopher Webster9, and Kevin Zahnle10 1Lunar and Planetary Institute/USRA, Houston, Texas, United States of America ([email protected]) 2NASA Goddard Space Flight Center, Greenbelt MD USA 3Planetary Science Laboratory, University of Michigan, Ann Arbor MI USA 4Center for Earth and Planetary Studies, Smithsonian Institution, Washington DC USA 5Dept. of Earth and Environmental Science, Wesleyan University, Middletown CT USA 6Planetary Science Institute, Tucson AZ USA 7Applied Physics Lab, Johns Hopkins University, Laurel MD USA 8Malin Space Science Systems, San Diego CA USA 9Jet Propulsion Laboratory, California Insitute of Technology, Pasadena CA USA 10NASA Ames Research Center, Moffet Field CA USA Understanding the divergent evolution of Venus and Earth is a fundamental problem in planetary science. Although Venus today has a hot, dry atmosphere, recent modeling suggests that Venus may have had a clement surface with liquid water until less than 1 billion years ago [1]. Venus today has a nearly stagnant lithosphere. However, Ishtar Terra’s folded mountain belts, 8-11 km high, morphologically resemble Tibet and the Himalaya mountains on Earth and apparently require several thousand kilometers of surface motion at some time in Venus’s past. -
The Official Journal of the Institute of Science & Technology – The
The Institute of Science & Technology The Institute of Science & Technology The Journal The Journal Winter 2011 Winter 2011 Kingfisher House 90 Rockingham Street Sheffield S1 4EB Tel: 0114 276 3197 [email protected] www.istonline.org.uk The Official Journal of The Institute of Science & Technology – The Professional Body for Specialist, Technical and Managerial Staff ISSN 2040-1868 The Journal The Official Publication of the Institute of Science & Technology ISSN 2040-1868 CONTENTS – Winter 2011 Editorial Ian Moulson Acting Chairman’s Report Terry Croft Letters to the Editor Rosina K Nyarko Astrobiology Colin Neve An inside view of a Venezuelan shrimp farm Carlos Conroy Origins, part 2: the general theory of relativity Estelle Asmodelle “My Lunar Estate”: the life of Hannah Jackson-Gwilt Alan Gall Teaching Science Christine Thompson Frog trade link to killer fungus Natural Environment Research Council Students to make ship history Arts & Humanities Research Council How parasites modify plants to attract insects Biotechnology & Biological Sciences Research Council Growing computers Engineering & Physical Sciences Research Council HIV study identifies key cellular defence mechanism Medical Research Council Physicists shed light on supernova mystery Science & Technology Facilities Council From the archives Alan Gall Journal puzzle solutions Alan Gall IST new members What is the IST? Cover images credits Front cover bottom left: Image courtesy of NASA Back cover top: Image courtesy of Wikipedia Commons Back cover middle: Image courtesy of NASA The Journal Page 1 Winter 2011 Editorial Welcome I hope that you enjoy this winter edition of the IST’s Journal. There are some really interesting and informative articles inside. -
Size, Scale and the Imaginary in the Work of Land Artists Michael Heizer, Walter De Maria and Dennis Oppenheim
Larger than life: size, scale and the imaginary in the work of Land Artists Michael Heizer, Walter De Maria and Dennis Oppenheim © Michael Albert Hedger A thesis in fulfillment of the requirements for the degree of Doctor of Philosophy Art History and Art Education UNIVERSITY OF NEW SOUTH WALES | Art & Design August 2014 PLEASE TYPE THE UNIVERSITY OF NEW SOUTH WALES Thesis/Dissertation Sheet Surname or Family name: Hedger First name: Michael Other name/s: Albert Abbreviation for degree as given in the University calendar: Ph.D. School: Art History and Education Faculty: Art & Design Title: Larger than life: size, scale and the imaginary in the work of Land Artists Michael Heizer, Walter De Maria and Dennis Oppenheim Abstract 350 words maximum: (PLEASE TYPE) Conventionally understood to be gigantic interventions in remote sites such as the deserts of Utah and Nevada, and packed with characteristics of "romance", "adventure" and "masculinity", Land Art (as this thesis shows) is a far more nuanced phenomenon. Through an examination of the work of three seminal artists: Michael Heizer (b. 1944), Dennis Oppenheim (1938-2011) and Walter De Maria (1935-2013), the thesis argues for an expanded reading of Land Art; one that recognizes the significance of size and scale but which takes a new view of these essential elements. This is achieved first by the introduction of the "imaginary" into the discourse on Land Art through two major literary texts, Swift's Gulliver's Travels (1726) and Shelley's sonnet Ozymandias (1818)- works that, in addition to size and scale, negotiate presence and absence, the whimsical and fantastic, longevity and death, in ways that strongly resonate with Heizer, De Maria and especially Oppenheim. -
The Geologic Evolution of Venus: Insights Into Earth History
The geologic evolution of Venus: Insights into Earth history James W. Head Department of Geological Sciences, Brown University, Providence, Rhode Island 02912, USA Through the clever use of stereo radargrammetric techniques on im- Higher-resolution radar imaging and more coverage were needed to fi nd ages from the Magellan mission to Venus in the 1990s, combined with out whether Venus was Earth-like. recent quantitative analyses of magma reservoirs on Earth, McGovern et In 1983, Soviet Union orbiters Venera 15 and 16 surveyed the north- al. (2014, p. 59 in this issue of Geology) resolve an important outstanding ern hemisphere (~30% of Venus), with radar imaging resolution of 1–2 km question dating from that era: What forces are responsible for the graben (Barsukov et al., 1992), showing that many highlands consist of very high- extending radially from large shield volcanoes? They show that, in addi- ly deformed terrain (tesserae), and that organized linear folded mountain tion to radial dike emplacement, the larger graben are readily accounted belts surround highland plateaus. Large volcanoes exist in abundance, but for by magma reservoir infl ation, providing new insight into processes of show little evidence for hot spot traces or convergent plate boundaries. magma ascent and eruption on Venus, and their relation to globally inter- Coronae looked like the fi ngerprints of mantle processes. Most remark- connected rift systems on Earth’s sibling planet. This new contribution ably, there were few impact craters, indicating an age on the order of only serves as a reminder of the importance of Venus to our understanding of hundreds of millions of years. -
VENUS Corona M N R S a Ak O Ons D M L YN a G Okosha IB E .RITA N Axw E a I O
N N 80° 80° 80° 80° L Dennitsa D. S Yu O Bachue N Szé K my U Corona EG V-1 lan L n- H V-1 Anahit UR IA ya D E U I OCHK LANIT o N dy ME Corona A P rsa O r TI Pomona VA D S R T or EG Corona E s enpet IO Feronia TH L a R s A u DE on U .TÜN M Corona .IV Fr S Earhart k L allo K e R a s 60° V-6 M A y R 60° 60° E e Th 60° N es ja V G Corona u Mon O E Otau nt R Allat -3 IO l m k i p .MARGIT M o E Dors -3 Vacuna Melia o e t a M .WANDA M T a V a D o V-6 OS Corona na I S H TA R VENUS Corona M n r s a Ak o ons D M L YN A g okosha IB E .RITA n axw e A I o U RE t M l RA R T Fakahotu r Mons e l D GI SSE I s V S L D a O s E A M T E K A N Corona o SHM CLEOPATRA TUN U WENUS N I V R P o i N L I FO A A ght r P n A MOIRA e LA L in s C g M N N t K a a TESSERA s U . P or le P Hemera Dorsa IT t M 11 km e am A VÉNUSZ w VENERA w VENUE on Iris DorsaBARSOVA E I a E a A s RM A a a OLO A R KOIDULA n V-7 s ri V VA SSE e -4 d E t V-2 Hiei Chu R Demeter Beiwe n Skadi Mons e D V-5 S T R o a o r LI s I o R M r Patera A I u u s s V Corona p Dan o a s Corona F e A o A s e N A i P T s t G yr A A i U alk 1 : 45 000 000 K L r V E A L D DEKEN t Baba-Jaga D T N T A a PIONEER or E Aspasia A o M e s S a (1 MM= 45 KM) S r U R a ER s o CLOTHO a A N u s Corona a n 40° p Neago VENUS s s 40° s 40° o TESSERA r 40° e I F et s o COCHRAN ZVEREVA Fluctus NORTH 0 500 1000 1500 2000 2500 KM A Izumi T Sekhm n I D . -
Vénus Les Transits De Vénus L’Exploration De Vénus Par Les Sondes Iconographie, Photos Et Additifs
VVÉÉNUSNUS Introduction - Généralités Les caractéristiques de Vénus Les transits de Vénus L’exploration de Vénus par les sondes Iconographie, photos et additifs GAP 47 • Olivier Sabbagh • Février 2015 Vénus I Introduction – Généralités Vénus est la deuxième des huit planètes du Système solaire en partant du Soleil, et la sixième par masse ou par taille décroissantes. La planète Vénus a été baptisée du nom de la déesse Vénus de la mythologie romaine. Symbolisme La planète Vénus doit son nom à la déesse de l'amour et de la beauté dans la mythologie romaine, Vénus, qui a pour équivalent Aphrodite dans la mythologie grecque. Cythère étant une épiclèse homérique d'Aphrodite, l'adjectif « cythérien » ou « cythéréen » est parfois utilisé en astronomie (notamment dans astéroïde cythérocroiseur) ou en science-fiction (les Cythériens, une race de Star Trek). Par extension, on parle d'un Vénus à propos d'une très belle femme; de manière générale, il existe en français un lexique très développé mêlant Vénus au thème de l'amour ou du plaisir charnel. L'adjectif « vénusien » a remplacé « vénérien » qui a une connotation moderne péjorative, d'origine médicale. Les cultures chinoise, coréenne, japonaise et vietnamienne désignent Vénus sous le nom d'« étoile d'or », et utilisent les mêmes caractères (jīnxīng en hanyu, pinyin en hiragana, kinsei en romaji, geumseong en hangeul), selon la « théorie » des cinq éléments. Vénus était connue des civilisations mésoaméricaines; elle occupait une place importante dans leur conception du cosmos et du temps. Les Nahuas l'assimilaient au dieu Quetzalcoatl, et, plus précisément, à Tlahuizcalpantecuhtli (« étoile du matin »), dans sa phase ascendante et à Xolotl (« étoile du soir »), dans sa phase descendante. -
Surface Processes in the Venus Highlands: Results from Analysis of Magellan and a Recibo Data
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 104, NO. E], PAGES 1897-1916, JANUARY 25, 1999 Surface processes in the Venus highlands: Results from analysis of Magellan and A recibo data Bruce A. Campbell Center for Earth and Planetary Studies, Smithsonian Institution, Washington, D.C. Donald B. Campbell National Astronomy and Ionosphere Ceiitei-, Cornell University, Ithaca, New York Christopher H. DeVries Department of Physics and Astronomy, University of Massachusetts, Amherst Abstract. The highlands of Venus are characterized by an altitude-dependent change in radar backscattcr and microwave emissivity, likely produced by surface-atmosphere weathering re- actions. We analyzed Magellan and Arecibo data for these regions to study the roughness of the surface, lower radar-backscatter areas at the highest elevations, and possible causes for areas of anomalous behavior in Maxwell Montes. Arecibo data show that circular and linear radar polarization ratios rise with decreasing emissivity and increasing Fresnel reflectivity, supporting the hypothesis that surface scattering dominates the return from the highlands. The maximum values of these polarization ratios are consistent with a significant component of multiple-bounce scattering. We calibrated the Arecibo backscatter values using areas of overlap with Magellan coverage, and found that the echo at high incidence angles (up to 70") from the highlands is lower than expected for a predominantly diffuse scattering regime. This behavior may be due to geometric effects in multiple scattering from surface rocks, but fur- ther modeling is required. Areas of lower radar backscatter above an upper critical elevation are found to be generally consistent across the equatorial highlands, with the shift in micro- wave properties occurring over as little as 5ÜÜ m of elevation.