Origin of the Solar System
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Planetary Surfaces
Chapter 4 PLANETARY SURFACES 4.1 The Absence of Bedrock A striking and obvious observation is that at full Moon, the lunar surface is bright from limb to limb, with only limited darkening toward the edges. Since this effect is not consistent with the intensity of light reflected from a smooth sphere, pre-Apollo observers concluded that the upper surface was porous on a centimeter scale and had the properties of dust. The thickness of the dust layer was a critical question for landing on the surface. The general view was that a layer a few meters thick of rubble and dust from the meteorite bombardment covered the surface. Alternative views called for kilometer thicknesses of fine dust, filling the maria. The unmanned missions, notably Surveyor, resolved questions about the nature and bearing strength of the surface. However, a somewhat surprising feature of the lunar surface was the completeness of the mantle or blanket of debris. Bedrock exposures are extremely rare, the occurrence in the wall of Hadley Rille (Fig. 6.6) being the only one which was observed closely during the Apollo missions. Fragments of rock excavated during meteorite impact are, of course, common, and provided both samples and evidence of co,mpetent rock layers at shallow levels in the mare basins. Freshly exposed surface material (e.g., bright rays from craters such as Tycho) darken with time due mainly to the production of glass during micro- meteorite impacts. Since some magnetic anomalies correlate with unusually bright regions, the solar wind bombardment (which is strongly deflected by the magnetic anomalies) may also be responsible for darkening the surface [I]. -
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. -
Peer Review Draft Synthesis and Assessment Product 4.2 Thresholds
1 Peer Review Draft 2 Synthesis and Assessment Product 4.2 3 Thresholds of Change in Ecosystems 4 Authors: Daniel B. Fagre (lead author), Colleen W. Charles, Craig 5 D. Allen, Charles Birkeland, F. Stuart Chapin, III, Peter M. 6 Groffman, Glenn R. Guntenspergen, Alan K. Knapp, A. David 7 McGuire, Patrick J. Mulholland, Debra P.C. Peters, Daniel D. 8 Roby, and George Sugihara 9 Contributing authors: Brandon T. Bestelmeyer, Julio L. 10 Betancourt, Jeffrey E. Herrick, and Douglas S. Kenney 11 U.S. Climate Change Science Program 12 Draft 5.0 SAP 4.2 9/26/2008 1 1 Table of Contents 2 Executive Summary............................................................................................................ 5 3 Introduction................................................................................................................... 5 4 Definitions.....................................................................................................................5 5 Development of Threshold Concepts............................................................................ 6 6 Principles of Thresholds ............................................................................................... 7 7 Case Studies.................................................................................................................. 8 8 Potential Management Responses............................................................................... 10 9 Recommendations...................................................................................................... -
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, -
GSA TODAY • Radon in Water, P
Vol. 8, No. 11 November 1998 INSIDE • Field Guide Editor, p. 5 GSA TODAY • Radon in Water, p. 10 • Women Geoscientists, p. 12 A Publication of the Geological Society of America • 1999 Annual Meeting, p. 31 Gas Hydrates: Greenhouse Nightmare? Energy Panacea or Pipe Dream? Bilal U. Haq, National Science Foundation, Division of Ocean Science, Arlington, VA 22230 ABSTRACT Recent interest in methane hydrates has resulted from the recognition that they may play important roles in the global carbon cycle and rapid climate change through emissions of methane from marine sediments and permafrost into the atmosphere, and in causing mass failure of sediments and structural changes on the continental slope. Their presumed large volumes are also consid- ered to be a potential source for future exploitation of methane as a resource. Natural gas hydrates occur widely on continental slope and rise, stabilized in place by high hydrostatic pressure and frigid bottom-temperature condi- tions. Change in these conditions, Figure 1. This seismic profile, over the landward side of Blake Ridge, crosses a salt diapir; the profile has either through lowering of sea level or been processed to show reflection strength. The prominent bottom simulating reflector (BSR) swings increase in bottom-water temperature, upward over the diapir because of the higher conductivity of the salt. Note the very strong reflections of may trigger the following sequence of gas accumulations below the gas-hydrate stability zone and the “blanking” of energy above it. Bright events: dissociation of the hydrate at its Spots along near-vertical faults above the diapir represent conduits for gas venting. -
Earth: Atmospheric Evolution of a Habitable Planet
Earth: Atmospheric Evolution of a Habitable Planet Stephanie L. Olson1,2*, Edward W. Schwieterman1,2, Christopher T. Reinhard1,3, Timothy W. Lyons1,2 1NASA Astrobiology Institute Alternative Earth’s Team 2Department of Earth Sciences, University of California, Riverside 3School of Earth and Atmospheric Science, Georgia Institute of Technology *Correspondence: [email protected] Table of Contents 1. Introduction ............................................................................................................................ 2 2. Oxygen and biological innovation .................................................................................... 3 2.1. Oxygenic photosynthesis on the early Earth .......................................................... 4 2.2. The Great Oxidation Event ......................................................................................... 6 2.3. Oxygen during Earth’s middle chapter ..................................................................... 7 2.4. Neoproterozoic oxygen dynamics and the rise of animals .................................. 9 2.5. Continued oxygen evolution in the Phanerozoic.................................................. 11 3. Carbon dioxide, climate regulation, and enduring habitability ................................. 12 3.1. The faint young Sun paradox ................................................................................... 12 3.2. The silicate weathering thermostat ......................................................................... 12 3.3. Geological -
Appendix I Lunar and Martian Nomenclature
APPENDIX I LUNAR AND MARTIAN NOMENCLATURE LUNAR AND MARTIAN NOMENCLATURE A large number of names of craters and other features on the Moon and Mars, were accepted by the IAU General Assemblies X (Moscow, 1958), XI (Berkeley, 1961), XII (Hamburg, 1964), XIV (Brighton, 1970), and XV (Sydney, 1973). The names were suggested by the appropriate IAU Commissions (16 and 17). In particular the Lunar names accepted at the XIVth and XVth General Assemblies were recommended by the 'Working Group on Lunar Nomenclature' under the Chairmanship of Dr D. H. Menzel. The Martian names were suggested by the 'Working Group on Martian Nomenclature' under the Chairmanship of Dr G. de Vaucouleurs. At the XVth General Assembly a new 'Working Group on Planetary System Nomenclature' was formed (Chairman: Dr P. M. Millman) comprising various Task Groups, one for each particular subject. For further references see: [AU Trans. X, 259-263, 1960; XIB, 236-238, 1962; Xlffi, 203-204, 1966; xnffi, 99-105, 1968; XIVB, 63, 129, 139, 1971; Space Sci. Rev. 12, 136-186, 1971. Because at the recent General Assemblies some small changes, or corrections, were made, the complete list of Lunar and Martian Topographic Features is published here. Table 1 Lunar Craters Abbe 58S,174E Balboa 19N,83W Abbot 6N,55E Baldet 54S, 151W Abel 34S,85E Balmer 20S,70E Abul Wafa 2N,ll7E Banachiewicz 5N,80E Adams 32S,69E Banting 26N,16E Aitken 17S,173E Barbier 248, 158E AI-Biruni 18N,93E Barnard 30S,86E Alden 24S, lllE Barringer 29S,151W Aldrin I.4N,22.1E Bartels 24N,90W Alekhin 68S,131W Becquerei -
South Pole-Aitken Basin
Feasibility Assessment of All Science Concepts within South Pole-Aitken Basin INTRODUCTION While most of the NRC 2007 Science Concepts can be investigated across the Moon, this chapter will focus on specifically how they can be addressed in the South Pole-Aitken Basin (SPA). SPA is potentially the largest impact crater in the Solar System (Stuart-Alexander, 1978), and covers most of the central southern farside (see Fig. 8.1). SPA is both topographically and compositionally distinct from the rest of the Moon, as well as potentially being the oldest identifiable structure on the surface (e.g., Jolliff et al., 2003). Determining the age of SPA was explicitly cited by the National Research Council (2007) as their second priority out of 35 goals. A major finding of our study is that nearly all science goals can be addressed within SPA. As the lunar south pole has many engineering advantages over other locations (e.g., areas with enhanced illumination and little temperature variation, hydrogen deposits), it has been proposed as a site for a future human lunar outpost. If this were to be the case, SPA would be the closest major geologic feature, and thus the primary target for long-distance traverses from the outpost. Clark et al. (2008) described four long traverses from the center of SPA going to Olivine Hill (Pieters et al., 2001), Oppenheimer Basin, Mare Ingenii, and Schrödinger Basin, with a stop at the South Pole. This chapter will identify other potential sites for future exploration across SPA, highlighting sites with both great scientific potential and proximity to the lunar South Pole. -
Space and Planetary Environment Criteria Guidelines for Use in Space Vehicle Development, 1 9 8 2 Revision Volume 1
NASA Technicd Memorandum 8 2 4 7 8 Space and Planetary Environment Criteria Guidelines for Use in Space Vehicle Development, 1 9 8 2 Revision Volume 1 Robert E. Smith ar~dGeorge S. West, Compilers George C. Marshall Space Flight Center Marshall Space Flight Center, Alabama National Aeronautics and Space Administration Sclentlfice and Technical lealormation 'Branch TABLE OF CONTENTS Page viii SECTIOP; 1. THE SUN ............................................ .......... 1.1 Introduction ....................... .. ............. ....a* 1.2 Brief Qualitative Description ............................. 1.3 Physical Properties .................................... .. 1.4 Solar Emanations - Descriptive .......................... 1.4.1 The Nature of the Sun's Output .................. 1.4.2 The Solar Cycle ................................... 1.4.3 Variation in the Sun's Output ................... .. 1.5 Solar Electromagnetic Radiation ........................... 1.5.1 Measurements of the Solar Constant ............... 1.5.2 Short-Term Fluctuations in the Solar Constant . .: . 1.5.3 The Solar Spectral Irradiance ..................... 1.6 Solar Plasma Emission .................................... 1.6.1 Properties of the Mean $olar Wind ................. 1.6.2 The Solar Wind and the Interplanetary Magnetic Field ............................................. 1.6.3 High-speed Streams ............................... 1.6.4 Coronal Transients ....................... .. .. .. ... 1.6.5 Spatial Variation of Solar Wind Properties ......... 1.6.6 Variation of the -
Research and Development Related to the Nevada Nuclear Waste Storage Investigations
LA-11443-PR LA_-H443-PR Progress Report Research and Development Related to the Nevada Nuclear Waste Storage Investigations October 1-December 31,1984 Compiled by K. W. Thomas DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United Sutes Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily stale or reflect those of the United States Government or any agency thereof. tfi / - 11 I iLos Alamos National Laboratory )Los Alamos.New Mexico 87545 Contents ABSTRACT 1 EXECUTIVE SUMMARY 2 I. INTRODUCTION 13 II. GEOCHEMISTRY 13 A. Groundwater Chemistry 13 B. Natural Isotope Chemistry 14 C. Hydrothermal Geochemistry 15 Effect of Silica Activity on the Temperature Stability of Clinoptilolite .... 16 D. Solubility Determinations 18 1. Important Radionuclides for Solubility and Sorption 18 2. Actinide Chemistry in Near-Neutral Solutions 20 3. Effect of Radiolysis on the Pu(VI)-Pu(V)-Pu(IV)-Colloid System .... 20 4. Complex Formation Between Am(III) and Carbonate 22 E. Sorption and Precipitation 23 1. -
Earth Resources NASA SP-7041 (33) a Continuing April 1982 NASA Bibliography with Indexes
Earth Resources NASA SP-7041 (33) A Continuing April 1982 NASA Bibliography with Indexes a 882-28695 National Aeronautics and Space Administration es Earth Resouro Earth Resources Earth Resources th Resources Ear i Resources Earth Resources Earth F sources Earth Re ACCESSION NUMBER RANGES Accession numbers cited in this Supplement fall within the following ranges. STAR (N-10000 Series) N82-10001 - N82-16039 IAA (A-10000 Series) A82-10001 - A82-18839 This bibliography was prepared by the NASA Scientific and Technical Information Facility operated for the National Aeronautics and Space Administration by PRC Government Information Systems. NASASP-7041(33) EARTH RESOURCES A CONTINUING BIBLIOGRAPHY WITH INDEXES Issue 33 A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced between January 1 and March 31, 1982 in • Scientific and Technical Aerospace Reports (STAR) • International Aerospace Abstracts (IAA). Scientific and Technical Information Branch 1982 National Aeronautics and Space Administration Washington, DC This supplement is available as NTISUB/038/093 from the National Technical Information Service (NTIS), Springfield, Virginia 22161 at the price of $10.50 domestic; $21.50 foreign for standing orders. Please note: Standing orders are subscriptions which do not terminate at the end of a year, as do regular subscriptions, but continue indefinitely unless specifically terminated by the subscriber. INTRODUCTION The technical literature described in this continuing bibliography may be helpful to researchers in numerous disciplines such as agriculture and forestry, geography and cartography, geology and mining, oceanography and fishing, environmental control, and many others. Until recently it was impossible for anyone to examine more than a minute fraction of the Earth's surface continuously. -
Supporting Information (SI) Appendix Persistence and Origin of the Lunar Core Dynamo
Supporting Information Corrected July 05, 2013 Supporting Information (SI) Appendix Persistence and origin of the lunar core dynamo Clément Suavet, Benjamin P. Weiss, William S. Cassata, David L. Shuster, Jérôme Gattacceca, Lindsey Chan, Ian Garrick-Bethell, James W. Head, Timothy L. Grove, and Michael D. Fuller 1. Previous paleomagnetic studies of high-K mare basalts During the Apollo era, paleomagnetic studies were carried out on at least six high-K basalts: 10017, 10022, 10024, 10049, 10057, and 10069. 10022 was thermally demagnetized (49), but the lack of published directional data precludes the identification of magnetization components. 10024 was found to carry an intense soft overprint and a higher coercivity component blocked from 5 to at least 50 mT, but spurious demagnetization effects prevented a detailed characterization of the latter (1). Similarly, 10057 was found to contain a soft overprint and a higher coercivity component from 9 to >18 mT, but a high-quality paleointensity value could not be obtained because the sample was not fully demagnetized (50, 51). 10069 was only demagnetized to <7 mT before thermal demagnetization was attempted, at which point the sample irreversibly altered (49). Because so many lunar rocks have poor magnetic recording properties (52), we decided to focus on two samples that appeared to be unusually well-behaved during previous AF demagnetization experiments: 10017 and 10049 (Fig. S1 and Table S6). The natural remanent magnetization (NRM) of 10017 was studied by three groups (13-16). Initial reports identified a directionally stable magnetization component during alternating field (AF) demagnetization of subsample 10017,64 up to 50 mT (13).