DOCSLIB.ORG

Tuesday, March 17, 1998 POSTER SESSION I 7:30 P.M

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Tuesday, March 17, 1998 POSTER SESSION I 7:30 P.M Tuesday, March 17, 1998 POSTER SESSION I 7:30 p.m. Space Center Houston MARS PATHFINDER: IMAGING, DUST, AND ROCKS Johnson J. R. Soderblom L. Kirk R. Gaddis L. Reid R. Smith P. H. Lemmon M. Britt D. Thomas N. Bell J. Bridges N. T. Anderson R. Herkenhoff K. Murchie S. M. Dummel A. Arnold G. Lampen P. Trauthan F. Photometric Imaging Sequences and Analysis at the Mars Pathfinder Landing Site Murchie S. Johnson J. McSween H. Bridges N. Anderson R. Britt D. Bell J. F. III Crisp J. Spectral Properties of Rocks at the Mars Pathfinder Landing Site Crisp J. A. The Effect of Thin Coatings of Dust or Soil on the Bulk APXS Composition of the Underlying Rocks at the Pathfinder Landing Site Pedersen C. T. Dinesen A. R. Hviid S. F. Madsen M. B. Knudsen J. M. Gunnlaugsson H. P. Goetz W. Hargraves R. B. Laboratory Experiments Simulating the Results of the Magnetic Properties Experiment on Mars Pathfinder Kraft M. D. Greeley R. Influence of Rock Coatings on Sand Abrasion at the Mars Pathfinder Landing Site Kirk R. L. Anderson J. Barrett J. Becker K. Becker T. Bennett A. Blue J. Cook D. Eliason E. Gaddis L. Garcia P. Gordon M. Hare T. Howington-Kraus A. Isbell C. Johnson J. Lee E. Morgan H. Redding B. Rosanova T. Soderblom L. Sucharski R. Sucharski T. Thompson K Torson J. Ward W. Dorrer E. Smith P. Britt D. Pathfinder Science Team Mapping the Sagan Memorial Station Site with the IMP Camera Parker T. J. “Super Resolution” of the Mars Pathfinder Landing Site, Using Manual Techniques Gaddis L. Soderblom L. Kirk R. Johnson J. Ward W. Anderson J. Barrett J. Becker K. Becker T. Bennett A. Blue J. Cook D. Eliason E. Garcia P. Gordon M. Hare T. Howington-Kraus A. Isbell C. Lee E. M. Redding B. Rosanova T. Sucharski R. Sucharski T. Thompson K. Torson J. Dorrer E. Smith P. Britt D. The Mars Pathfinder “Super Pan”: A U.S.G.S. Cartographic Product Kanefsky B. Parker T. J. Cheeseman P. C. Super-Resolution Results from Pathfinder IMP Stoker C. R. Blackmon T. Hagen J. Kanefsky B. Rasmussen D. Schwehr K. Sims M. Zbinden E. Marsmap: An Interactive Virtual Reality Model of the Pathfinder Landing Site Hauber E. Jaumann R. Mosangini C. Russ N. Trauthan F. Matz K. D. Fabel O. Rocks at the Pathfinder Landing Site, Mars: Identification and Size Distribution Basilevsky A. T. Markiewicz W. J. Keller H. U. Morphology of Rocks Within and Nearby Rock Garden: Mars Pathfinder Landing Site Lowman P. D. Jr. Andesites on Mars: Implications for the Origin of Terrestrial Continental Crust Nelson D. M. Greeley R. Xanthe Terra Outflow Channel Geology at the Mars Pathfinder Landing Site Marchenko A. G. Basilevsky A. T. Neukum G. Hauber E. Hoffmann H. Cook A. C. The Study of the Mouth of Ares and Tiu Valles, Mars Koehler U. Hiesinger H. Hauber E. Terrestrial Analogs to the MPF Landing Site: Investigation of Morphologies of Sander in Northern Iceland WATER ON MARS Costard F. Gosset J. P. Ground-Ice Distribution on Mars Based on GIS Analysis Koroshetz J. Barlow N. G. Possible Near-Surface Ice Reservoir South of Valles Marineris, Mars Tanaka K. L. Dohm J. M. Lias J. H. Hare T. M. Valley Erosion in Thaumasia Region of Mars Caused by Hydrothermal and Seismic Activity Grant J. A. Geologic Mapping and Drainage Morphometry in Margaritifer Sinus, Mars Scott E. D. Wilson L. Evidence for Fluvial Features Produced by Sill Emplacement on the Upper Flanks of Ascraeus Mons Volcano, Mars Price K. H. Cantu O. R. Prouty D. B. Geologic Mapping of the Dao and Niger Valles Source Region, Mars Forsythe R. D. Blackwelder C. W. Closed Drainage Crater Basins of the Martian Highlands; Constraints on the Early Martian Hydrologic Cycle Parker T. J. Mapping of Possible “Oceanus Borealis” Shorelines on Mars: A Status Report Mosangini C. Komatsu G. Geomorphology of Kasei Valles and Scale of Flooding Episodes Ewing R. C. Schenk P. M. Formation of Debris Aprons on Mars: Viking Stereotopographic Mapping Demura H. Abe Y. Spreading Flow at the Mouth of Outflow Channel on Mars Kraal E. R. Wong M. P. Grosfils E. B. Gilmore M. S. Kozak S. J. Reinen L. A. The Origin and Modification of a Trough in the Nili Fossae, Mars McKenzie D. Nimmo F. Martian Dikes, Outflow Channels and Valles Marineris Kirkland L. E. Forney P. B. Herr K. C. Mariner Mars 6/7 Infrared Spectra: New Calibration and a Search for Water Ice Clouds Lorenz R. D. Containerless Thermal Analysis: In-Situ Microinstrumentation for Detecting Ice and Evaporites on Mars Drake D. M. Clark B. C. Jakosky B. M. Reedy R. Squyres S. W. A LiF Silicon Sandwich Counter to Measure Water Content of Planetary Surfaces MARS GLOBAL SURVEYOR RESULTS: SURFACE AND ATMOSPHERE Acuna M. H. Connerney J. E. P. Wasilewski P. J. Frey H. V. Lin R. P. Anderson K. A. Carlson C. W. McFadden J. Curtis D. W. Mitchell D. Reme H. Cros A. Medale J. L. Mazelle C. Sauvand J. A. D’Uston C. Bauer S. J. Cloutier P. Mayhew M. Ness N. F. Magnetic Field at Mars: Preliminary Results of the Mars Global Surveyor Mission Aharonson O. Zuber M. T. Neumann G. A. Smith D. E. Head J. W. Slopes and Stochastic Properties of the Northern Hemisphere of Mars from MOLA Altimetry Zuber M. T. Smith D. E. The Relationship of MOLA Northern Hemisphere Topography to the 6.1 mbar Atmospheric Pressure Surface of Mars Garvin J. B. Sakimoto S. E. H. Frawley J. J. Martian Impact Crater Ejecta Topography as Measured by the Mars Orbiter Laser Altimeter (MOLA) Frey H. V. Sakimoto S. E. H. Roark J. H. MOLA Topography and the Isidis Basin: Constraints on Basin Center and Ring Diameters Frey H. V. Sakimoto S. E. H. Roark J. H. A Tale of Two Craters: MOLA Constraints on Timing of the Formation of the Crustal Dichotomy Boundary Zone and Its Associated Topography on Mars Frey H. V. Sakimoto S. E. H. Roark J. H. MOLA Topography and Stratigraphy of Geologic Units at the Dichotomy Boundary: The Medusae Fossae Formation Ivanov A. B. Muhleman D. O. Atmospheric Opacity from Mars Observer Laser Altimiter Observations Moreau D. Marten A. Biraud Y. Meridional and Seasonal Distributions of Trace Gases in the Lower and Middle Atmosphere of Mars MARS: THE KITCHEN SINK Frey H. Roark J. Origin of the Western Arabian Shelf: Oblique Impact Formation of the Chryse Basin? Roddy D. J. Hare T. M. Wyatt M. B. Isbell N. R. Mardock C. L. Soderblom L. M. Boyce J. M. II) Martian Impact Craters, Ejecta Blankets, and Related Morphologic Features: Preliminary Results from Computer Digital Inventory Using Arc/Info and Arcview Roddy D. J. Isbell N. R. Mardock C. L. Hare T. M. Wyatt M. B. Soderblom L. M. Boyce J. M. I) Martian Impact Craters, Ejecta Blankets, and Related Morphologic Features: Computer Digital Inventory in Arc/Info and Arcview Format Foxx R. Brugger C. Grosfils E. Reinen L. Gilmore M. Kozak S. Cooper J. Morphology and Possible Volcanic Origin of Sub-Kilometer Domes in the Arrhenius Region, Mars Bulmer M. H. McGovern P. J. The Role of Mass Movements in the Evolution of Olympus Mons Head J. W. Seibert N. Pratt S. Smith D. Zuber M. Garvin J. B. McGovern P. J. MOLA Science Team Volcanic Calderas on Mars: Initial Views Using Mars Orbiter Laser Altimeter Data Head J. W. Wilson L. Tharsis Montes as Composite Volcanoes?: 1. The Role of Explosive Volcanism in Edifice Construction and Implications for the Volatile Contents of Edifice-forming Magmas Joens H.-P. Comparative Planetology: Coronae on Venus, Mars, and Earth Joens H.-P. Oscillation Ridges Along the Flanks of the Tharsis Montes, Mars Mitchell K. L. Wilson L. Implications of the Apparent Absence of Maars in Viking Orbiter Imagery Anderson R. C. Golombek M. P. Franklin B. J. Tanaka K. L. Dohm J. M. Lias J. H. Peer B. Centers of Tectonic Activity Through Time for the Western Hemisphere of Mars Cooper C. D. Mustard J. F. Rates of Erosion in Oxia Palus, Mars Edgett K. S. Parker T. J. “Bright” Aeolian Dunes on Mars: Viking Orbiter Observations Reese C. C. Solomatov V. S. Moresi L.-N. Non-Newtonian Stagnant Lid Convection: Application to Mars Smith D. E. Zuber M. T. Lemoine F. G. Tracadas P. Gravity Field Modeling and Orbit Determination with MGS Watters T. R. Robinson M. S. Lobate Scarps and the Origin of the Crustal Dichotomy on Mars Zimbelman J. R. Johnston A. K. Patel S. D. Photogeologic Constraints on the Emplacement of the Medusae Fossae Formation, Mars Stooke P. J. Locating the Viking 2 Landing Site CHONDRITES AND PRESOLAR/NEBULA PROCESSES Genge M. J. Clark R. J. H. Firth S. Batchelder M. Grady M. M. Parent Body Aqueous Alteration of Kamacite in the Kakangari Chondrite Goodrich C. A. Delaney J. S. Origin of the Total Iron – Oxidized Iron – ∆17O Correlations Among Ordinary Chondrites Weisberg M. K. Prinz M. Zolensky M. E. Clayton R. N. Mayeda T. K. Petrologic and Oxygen Isotopic Study of Dark Inclusions in the Wells LL3 Ordinary Chondrite Bridges J. C. Franchi I. A. Sexton A. S. Pillinger C. T. Mineralogical Controls on Oxygen Isotopic Exchange in UOCs Komatsu M. Reid A. M. LL Chondrites and Prior’s Rules Noble S. K. Lofgren G. E. Melting Histories of Chondrule Precursor Aggregates in UOC’s Newton J. Franchi I. A. Pillinger C. T. An Oxygen Isotope Study of Enstatite Meteorites Krestina N. Bogdanovski O. Jagoutz E. Kurat G. A Stepwise Technique of Chondrule Abrasion and Its Application to Study of Isotopic Systems in Single Chondrules Genge M.
Load more

Recommended publications
  • Supervolcanoes Within an Ancient Volcanic Province in Arabia Terra, Mars 2 3 4 Joseph
    EMBARGOED BY NATURE 1 1 Supervolcanoes within an ancient volcanic province in Arabia Terra, Mars 2 3 4 Joseph. R. Michalski 1,2 5 1Planetary Science Institute, Tucson, Arizona 85719, [email protected] 6 2Dept. of Earth Sciences, Natural History Museum, London, United Kingdom 7 8 Jacob E. Bleacher3 9 3NASA Goddard Space Flight Center, Greenbelt, MD, USA. 10 11 12 Summary: 13 14 Several irregularly shaped craters located within Arabia Terra, Mars represent a 15 new type of highland volcanic construct and together constitute a previously 16 unrecognized martian igneous province. Similar to terrestrial supervolcanoes, these 17 low-relief paterae display a range of geomorphic features related to structural 18 collapse, effusive volcanism, and explosive eruptions. Extruded lavas contributed to 19 the formation of enigmatic highland ridged plains in Arabia Terra. Outgassed sulfur 20 and erupted fine-grained pyroclastics from these calderas likely fed the formation of 21 altered, layered sedimentary rocks and fretted terrain found throughout the 22 equatorial region. Discovery of a new type of volcanic construct in the Arabia 23 volcanic province fundamentally changes the picture of ancient volcanism and 24 climate evolution on Mars. Other eroded topographic basins in the ancient Martian 25 highlands that have been dismissed as degraded impact craters should be 26 reconsidered as possible volcanic constructs formed in an early phase of 27 widespread, disseminated magmatism on Mars. 28 29 30 EMBARGOED BY NATURE 2 31 The source of fine-grained, layered deposits1,2 detected throughout the equatorial 32 region of Mars3 remains unresolved, though the deposits are clearly linked to global 33 sedimentary processes, climate change, and habitability of the surface4.
    [Show full text]
  • The History Group's Silver Jubilee
    History of Meteorology and Physical Oceanography Special Interest Group Newsletter 1, 2010 ANNUAL REPORT CONTENTS We asked in the last two newsletters if you Annual Report ........................................... 1 thought the History Group should hold an Committee members ................................ 2 Annual General Meeting. There is nothing in Mrs Jean Ludlam ...................................... 2 the By-Law s or Standing Orders of the Royal Meteorological Society that requires the The 2010 Summer Meeting ..................... 3 Group to hold one, nor does Charity Law Report of meeting on 18 November .......... 4 require one. Which papers have been cited? .............. 10 Don’t try this at home! ............................. 10 Only one person responded, and that was in More Richard Gregory reminiscences ..... 11 passing during a telephone conversation about something else. He was in favour of Storm warnings for seafarers: Part 2 ....... 13 holding an AGM but only slightly so. He Swedish storm warnings ......................... 17 expressed the view that an AGM provides an Rikitea meteorological station ................. 19 opportunity to put forward ideas for the More on the D-Day forecast .................... 20 Group’s committee to consider. Recent publications ................................ 21 As there has been so little response, the Did you know? ........................................ 22 Group’s committee has decided that there will Date for your diary .................................. 23 not be an AGM this year. Historic picture ........................................ 23 2009 members of the Group ................... 24 CHAIRMAN’S REVIEW OF 2009 by Malcolm Walker year. Sadly, however, two people who have supported the Group for many years died during I begin as I did last year. Without an enthusiastic 2009. David Limbert passed away on 3 M a y, and conscientious committee, there would be no and Jean Ludlam died in October (see page 2).
    [Show full text]
  • No. 40. the System of Lunar Craters, Quadrant Ii Alice P
    NO. 40. THE SYSTEM OF LUNAR CRATERS, QUADRANT II by D. W. G. ARTHUR, ALICE P. AGNIERAY, RUTH A. HORVATH ,tl l C.A. WOOD AND C. R. CHAPMAN \_9 (_ /_) March 14, 1964 ABSTRACT The designation, diameter, position, central-peak information, and state of completeness arc listed for each discernible crater in the second lunar quadrant with a diameter exceeding 3.5 km. The catalog contains more than 2,000 items and is illustrated by a map in 11 sections. his Communication is the second part of The However, since we also have suppressed many Greek System of Lunar Craters, which is a catalog in letters used by these authorities, there was need for four parts of all craters recognizable with reasonable some care in the incorporation of new letters to certainty on photographs and having diameters avoid confusion. Accordingly, the Greek letters greater than 3.5 kilometers. Thus it is a continua- added by us are always different from those that tion of Comm. LPL No. 30 of September 1963. The have been suppressed. Observers who wish may use format is the same except for some minor changes the omitted symbols of Blagg and Miiller without to improve clarity and legibility. The information in fear of ambiguity. the text of Comm. LPL No. 30 therefore applies to The photographic coverage of the second quad- this Communication also. rant is by no means uniform in quality, and certain Some of the minor changes mentioned above phases are not well represented. Thus for small cra- have been introduced because of the particular ters in certain longitudes there are no good determi- nature of the second lunar quadrant, most of which nations of the diameters, and our values are little is covered by the dark areas Mare Imbrium and better than rough estimates.
    [Show full text]
  • Glossary Glossary
    Glossary Glossary Albedo A measure of an object’s reflectivity. A pure white reflecting surface has an albedo of 1.0 (100%). A pitch-black, nonreflecting surface has an albedo of 0.0. The Moon is a fairly dark object with a combined albedo of 0.07 (reflecting 7% of the sunlight that falls upon it). The albedo range of the lunar maria is between 0.05 and 0.08. The brighter highlands have an albedo range from 0.09 to 0.15. Anorthosite Rocks rich in the mineral feldspar, making up much of the Moon’s bright highland regions. Aperture The diameter of a telescope’s objective lens or primary mirror. Apogee The point in the Moon’s orbit where it is furthest from the Earth. At apogee, the Moon can reach a maximum distance of 406,700 km from the Earth. Apollo The manned lunar program of the United States. Between July 1969 and December 1972, six Apollo missions landed on the Moon, allowing a total of 12 astronauts to explore its surface. Asteroid A minor planet. A large solid body of rock in orbit around the Sun. Banded crater A crater that displays dusky linear tracts on its inner walls and/or floor. 250 Basalt A dark, fine-grained volcanic rock, low in silicon, with a low viscosity. Basaltic material fills many of the Moon’s major basins, especially on the near side. Glossary Basin A very large circular impact structure (usually comprising multiple concentric rings) that usually displays some degree of flooding with lava. The largest and most conspicuous lava- flooded basins on the Moon are found on the near side, and most are filled to their outer edges with mare basalts.
    [Show full text]
  • Martian Crater Morphology
    ANALYSIS OF THE DEPTH-DIAMETER RELATIONSHIP OF MARTIAN CRATERS A Capstone Experience Thesis Presented by Jared Howenstine Completion Date: May 2006 Approved By: Professor M. Darby Dyar, Astronomy Professor Christopher Condit, Geology Professor Judith Young, Astronomy Abstract Title: Analysis of the Depth-Diameter Relationship of Martian Craters Author: Jared Howenstine, Astronomy Approved By: Judith Young, Astronomy Approved By: M. Darby Dyar, Astronomy Approved By: Christopher Condit, Geology CE Type: Departmental Honors Project Using a gridded version of maritan topography with the computer program Gridview, this project studied the depth-diameter relationship of martian impact craters. The work encompasses 361 profiles of impacts with diameters larger than 15 kilometers and is a continuation of work that was started at the Lunar and Planetary Institute in Houston, Texas under the guidance of Dr. Walter S. Keifer. Using the most ‘pristine,’ or deepest craters in the data a depth-diameter relationship was determined: d = 0.610D 0.327 , where d is the depth of the crater and D is the diameter of the crater, both in kilometers. This relationship can then be used to estimate the theoretical depth of any impact radius, and therefore can be used to estimate the pristine shape of the crater. With a depth-diameter ratio for a particular crater, the measured depth can then be compared to this theoretical value and an estimate of the amount of material within the crater, or fill, can then be calculated. The data includes 140 named impact craters, 3 basins, and 218 other impacts. The named data encompasses all named impact structures of greater than 100 kilometers in diameter.
    [Show full text]
  • June 9, 2020 LIST of ABSENTEE VOTERS HOLDING BALLOTS – NAMES
    WARSAW CENTRAL SCHOOL BUDGET/BOARD VOTE – June 9, 2020 LIST OF ABSENTEE VOTERS HOLDING BALLOTS – NAMES Abbasey, Salman Aumer, Andrew J. Bauer, James E. Abbott, John Axtell, Paula A. Bauer, Janet M. Ackerman, James Backlas, Frederick A. Jr Bauer, Michael Ackerman, Susan M. Bagg , Robert L. Bauer, Michelle Adolf, Jeremy J. Bagg, Kenneth G. Baxter, Susan Agrawal, Rajendra Bagg, Patty Bayliss, Bruce A. Aguado, Andrew E. Bagley, Raymond F. Bayoumi, Ahmed Ahl, Florence Bailey, Betty J. Beach, Douglas A. Aker, James D. Bailey, Judith L. Beach, Robert L. Akin, Claudia J. Bailey, Lyndsay Beals, Duane M. Alband, Jeffrey L. Bailey, Richard L. Beals, Shane Alcaraz, Christina M. Bailey, Stephen Beardsley, Peter G. Alderson, Donald P. Bailey, Stephen Beck, Michael J. Aldinger, Suzanne Bailey, Tara L. Beckstrand, Benjamine C. Aldrich, Heather L. Baize, Mary A. Beckstrand, Denise C. Aldrich, Jordan A. Baker, Arlene W. Beilein, Paul T. Aldrich, Kathryn J. Baker, Charles O. Beinhauer, Joseph F. Alexander, Christopher J. Baker, Frederic Belden, Barbara A. Alexander, Tara Baker, Gregory S. Belden, James C. Allen, Patricia A. Baker, Karen Bell, David K. Allison, Eddie R. Baker, Kirk E. Bell, Kathleen D. Almeter, David J Baker, Kristina Bell, Lorraine F. Almeter, George Anna Baker, Nichlos Bell, Milda Almeter, Nathan A. Baker, Peggy J. Bell, Mildred E. Almeter, Steven A. Baker, Roger O. Bellaire, Donald Ames, Gregory K. Baker, Shawn R. Bellaire, Donald W. Sr Ames, Richard A. Bakowski, Christopher Belles, Cody J. Andalora, Ingeburg Ballard, Joanne R. Bellinger, Heather Andalora, Orah Ballerstein, Lisa Bender, Gloria Andrews, Lee H. Ballew, Marjorie Bender, Sidney Antinore, Hope Bannister, Jeffrey H.
    [Show full text]
  • Understanding the History of Arabia Terra, Mars Through Crater-Based Tests Karalee Brugman University of Colorado Boulder
    University of Colorado, Boulder CU Scholar Undergraduate Honors Theses Honors Program Spring 2014 Understanding the History of Arabia Terra, Mars Through Crater-Based Tests Karalee Brugman University of Colorado Boulder Follow this and additional works at: http://scholar.colorado.edu/honr_theses Recommended Citation Brugman, Karalee, "Understanding the History of Arabia Terra, Mars Through Crater-Based Tests" (2014). Undergraduate Honors Theses. Paper 55. This Thesis is brought to you for free and open access by Honors Program at CU Scholar. It has been accepted for inclusion in Undergraduate Honors Theses by an authorized administrator of CU Scholar. For more information, please contact [email protected]. ! UNDERSTANDING+THE+HISTORY+OF+ARABIA+TERRA,+MARS++ THROUGH+CRATER4BASED+TESTS+ Karalee K. Brugman Geological Sciences Departmental Honors Thesis University of Colorado Boulder April 4, 2014 Thesis Advisor Brian M. Hynek | Geological Sciences Committee Members Charles R. Stern | Geological Sciences Fran Bagenal | Astrophysical and Planetary Sciences Stephen J. Mojzsis | Geological Sciences ABSTRACT' Arabia Terra, a region in the northern hemisphere of Mars, has puzzled planetary scientists because of its odd assemblage of characteristics. This makes the region difficult to categorize, much less explain. Over the past few decades, several hypotheses for the geological history of Arabia Terra have been posited, but so far none are conclusive. For this study, a subset of the Mars crater database [Robbins and Hynek, 2012a] was reprocessed using a new algorithm [Robbins and Hynek, 2013]. Each hypothesis’s effect on the crater population was predicted, then tested via several crater population characteristics including cumulative size-frequency distribution, depth-to-diameter ratio, and rim height.
    [Show full text]
  • Is Extraterrestrial Organic Matter Relevant to the Origin of Life on Earth?
    IS EXTRATERRESTRIAL ORGANIC MATTER RELEVANT TO THE ORIGIN OF LIFE ON EARTH? D. C. B. WHITTET Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180, U.S.A. (Received 19 August 1996) Abstract. I review the relative importance of internal and external sources of prebiotic molecules on Earth at the time of life's origin 3.7 Gyr ago. The ef®ciency of synthesis in the Earth's atmosphere was critically dependent on its oxidation state. If the early atmosphere was non-reducing and CO2- dominated, external delivery might have been the dominant source. Interplanetary dust grains and micrometeorites currently deliver carbonaceous matter to the Earth's surface at a rate of 3 5 7 10 kg/yr (equivalent to a biomass in 2 Gyr), but this may have been as high as 5 10 kg/yr (a biomass in only 10 Myr) during the epoch of late bombardment. Much of the incoming material is in the form of chemically inactive kerogens and amorphous carbon; but if the Earth once had a dense (10-bar) atmosphere, small comets rich in a variety of prebiotic molecules may have been suf®ciently air-braked to land non-destructively. Lingering uncertainties regarding the impact history of the Earth and the density and composition of its early atmosphere limit our ability to draw ®rm conclusions. 1. Introduction In at least one sense, a connection between the Universe at large and life in our small corner of it is inevitable. The hydrogen, carbon, nitrogen, oxygen, and other elements that make up our bodies and other living things were created billions of years ago in the interiors of stars and, in the case of hydrogen, in the the Big Bang itself (see Trimble, 1997, in this volume for an eloquent review).
    [Show full text]
  • March 21–25, 2016
    FORTY-SEVENTH LUNAR AND PLANETARY SCIENCE CONFERENCE PROGRAM OF TECHNICAL SESSIONS MARCH 21–25, 2016 The Woodlands Waterway Marriott Hotel and Convention Center The Woodlands, Texas INSTITUTIONAL SUPPORT Universities Space Research Association Lunar and Planetary Institute National Aeronautics and Space Administration CONFERENCE CO-CHAIRS Stephen Mackwell, Lunar and Planetary Institute Eileen Stansbery, NASA Johnson Space Center PROGRAM COMMITTEE CHAIRS David Draper, NASA Johnson Space Center Walter Kiefer, Lunar and Planetary Institute PROGRAM COMMITTEE P. Doug Archer, NASA Johnson Space Center Nicolas LeCorvec, Lunar and Planetary Institute Katherine Bermingham, University of Maryland Yo Matsubara, Smithsonian Institute Janice Bishop, SETI and NASA Ames Research Center Francis McCubbin, NASA Johnson Space Center Jeremy Boyce, University of California, Los Angeles Andrew Needham, Carnegie Institution of Washington Lisa Danielson, NASA Johnson Space Center Lan-Anh Nguyen, NASA Johnson Space Center Deepak Dhingra, University of Idaho Paul Niles, NASA Johnson Space Center Stephen Elardo, Carnegie Institution of Washington Dorothy Oehler, NASA Johnson Space Center Marc Fries, NASA Johnson Space Center D. Alex Patthoff, Jet Propulsion Laboratory Cyrena Goodrich, Lunar and Planetary Institute Elizabeth Rampe, Aerodyne Industries, Jacobs JETS at John Gruener, NASA Johnson Space Center NASA Johnson Space Center Justin Hagerty, U.S. Geological Survey Carol Raymond, Jet Propulsion Laboratory Lindsay Hays, Jet Propulsion Laboratory Paul Schenk,
    [Show full text]
  • A Study About the Temporal Constraints on the Martian Yardangs’ Development in Medusae Fossae Formation
    remote sensing Article A Study about the Temporal Constraints on the Martian Yardangs’ Development in Medusae Fossae Formation Jia Liu 1,2 , Zongyu Yue 1,3,*, Kaichang Di 1,3 , Sheng Gou 1,4 and Shengli Niu 4 1 State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100101, China; [email protected] (J.L.); [email protected] (K.D.); [email protected] (S.G.) 2 University of Chinese Academy of Sciences, Beijing 100049, China 3 CAS Center for Excellence in Comparative Planetology, Hefei 230026, China 4 State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau 999078, China; [email protected] * Correspondence: [email protected]; Tel.: +86-10-64889553 Abstract: The age of Mars yardangs is significant in studying their development and the evolution of paleoclimate conditions. For planetary surface or landforms, a common method for dating is based on the frequency and size distribution of all the superposed craters after they are formed. However, there is usually a long duration for the yardangs’ formation, and they will alter the superposed craters, making it impossible to give a reliable dating result with the method. An indirect method by analyzing the ages of the superposed layered ejecta was devised in the research. First, the layered ejecta that are superposed on and not altered by the yardangs are identified and mapped. Then, the ages of the layered ejecta are derived according to the crater frequency and size distribution on them. These ages indicate that the yardangs ceased development by these times, and the ages are valuable for studying the evolution of the yardangs.
    [Show full text]
  • Binary Asteroids and the Formation of Doublet Craters
    ICARUS 124, 372±391 (1996) ARTICLE NO. 0215 Binary Asteroids and the Formation of Doublet Craters WILLIAM F. BOTTKE,JR. Division of Geological and Planetary Sciences, California Institute of Technology, Mail Code 170-25, Pasadena, California 91125 E-mail: [email protected] AND H. JAY MELOSH Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721 Received April 29, 1996; revised August 14, 1996 found we could duplicate the observed fraction of doublet cra- At least 10% (3 out of 28) of the largest known impact craters ters found on Earth, Venus, and Mars. Our results suggest on Earth and a similar fraction of all impact structures on that any search for asteroid satellites should place emphasis Venus are doublets (i.e., have a companion crater nearby), on km-sized Earth-crossing asteroids with short-rotation formed by the nearly simultaneous impact of objects of compa- periods. 1996 Academic Press, Inc. rable size. Mars also has doublet craters, though the fraction found there is smaller (2%). These craters are too large and too far separated to have been formed by the tidal disruption 1. INTRODUCTION of an asteroid prior to impact, or from asteroid fragments dispersed by aerodynamic forces during entry. We propose that Two commonly held paradigms about asteroids and some fast rotating rubble-pile asteroids (e.g., 4769 Castalia), comets are that (a) they are composed of non-fragmented after experiencing a close approach with a planet, undergo tidal chunks of rock or rock/ice mixtures, and (b) they are soli- breakup and split into multiple co-orbiting fragments.
    [Show full text]
  • Martian Chronology: Toward Resolution of the 2005 “Controversy” and Evidence for Obliquity-Driven Resurfacing Processes
    Seventh International Conference on Mars 3318.pdf MARTIAN CHRONOLOGY: TOWARD RESOLUTION OF THE 2005 “CONTROVERSY” AND EVIDENCE FOR OBLIQUITY-DRIVEN RESURFACING PROCESSES. William K. Hartmann, Planetary Science Institute, 1700 E. Ft. Lowell Rd., Ste 106, Tucson AZ 85719-2395 USA; [email protected] Direct Observations of New Crater Formation Some of the controversial issues are now moot, and others Confirm Our Isochrons: Malin et al. [1] recently can be answered. reported discovery of 20 Martian impact sites where new First, many authors have repeated a statement that craters, of diameter D = 2 m to 125 m, formed in a crater counting yields useful ages only if the craters used seven-year period. The craters formed at different times are all primaries [3-6], and have indicated that my and appear to mark primary impacts, not secondaries. isochrons plot my estimates of the number of primaries The Malin et al. results match their earlier result (MGS [5]. This is incorrect. I have consistently attempted since web site www.msss.com), proposing a small crater ~ 1967 to measure the background buildup of primaries formation rate for the last 100 years. As seen in Fig. 1, plus scattered distant secondaries as a function of time their two data sets both match the crater formation rates (outside obvious clusters and rays) on various geologic I have used [2] in estimating crater retention ages of formations [7]. This approach was also recommended in surfaces on Mars. Even if only half their detections are the multi-author 1981 Basaltic Volcanism Study Project correct, their rate is still within about an order of volume [8].
    [Show full text]