Sociated with the Apparently Stellar Images. the Sources Have Small Angular Diameters, from Radio and Optical Measures-Less Than a Second of Arc
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Index Page numbers in italics refer to Tables or Figures Acasta gneiss 137, 138 Chladni, Ernst 94, 97 Adam, Robert 8, 11 chlorite 70, 71 agriculture, Hutton on 177 chloritoid stability 70 Albritton, Claude C. 100 Clerk Jnr, John 3 alumina (A1203), reaction in metamorphism 67-71 Clerk of Odin, John 5, 6, 7, 10, 11 andalusite stability 67 Clerk-Maxwell, George 10 anthropic principle 79-80 climate change 142 Apex basalt 140 Lyell on 97-8 Archean cratons (archons) 28, 31-2 coal as Earth heat source 176 Arizona Crater 98-9 coesite stability 65 Arran, Isle of 170 Columbia River basalts 32 asthenosphere 22 comets 89-90, 147-8 astrobleme 101 short v. long period 92 atmospheric composition 83-6 as source of life 148-9 Austral Volcanic Chain 24 continental flood basalt (CFB) 20, 23, 32 cordierite stability 67 craters, impact Bacon, Francis 21 Chixulub 109, 110, 143 Baldwin, Ralph 102 early ideas on 90, 98 Banks, Sir Joseph 96 modern occurrences 91, 98-101 Barringer, Daniel Moreau 99 Morokweng 142 Barringer Crater 99, 102, 103 modern research 102-3 basalt periodicity of 111-12 described by Hall 40-1 creation, Hutton's views on 76 mid-ocean ridge (MORB) 16-17, 20-1, 22, 23, 30-1 Creech, William 5 modern experiments on 44-7 Cretaceous-Tertiary impacts 141 ocean island (OIB) 20, 23 crust formation 17 see also flood basalt cryptoexplosion structures 101 Benares (India) meteorite shower 96 cryptovolcanic structures 100-1 Biot, Jean-Baptiste 97 Black, Joseph 4, 9, 10, 11, 42, 171 Boon, John D. -
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. -
Hadley's Principle: Understanding and Misunderstanding the Trade
History of Meteorology 3 (2006) 17 Hadley’s Principle: Understanding and Misunderstanding the Trade Winds Anders O. Persson Department for research and development Swedish Meteorological and Hydrological Institute SE 601 71 Norrköping, Sweden [email protected] Old knowledge will often be rediscovered and presented under new labels, causing much confusion and impeding progress—Tor Bergeron.1 Introduction In May 1735 a fairly unknown Englishman, George Hadley, published a groundbreaking paper, “On the Cause of the General Trade Winds,” in the Philosophical Transactions of the Royal Society. His path to fame was long and it took 100 years to have his ideas accepted by the scientific community. But today there is a “Hadley Crater” on the moon, the convectively overturning in the tropics is called “The Hadley Cell,” and the climatological centre of the UK Meteorological Office “The Hadley Centre.” By profession a lawyer, born in London, George Hadley (1685-1768) had in 1735 just became a member of the Royal Society. He was in charge of the Society’s meteorological work which consisted of providing instruments to foreign correspondents and of supervising, collecting and scrutinizing the continental network of meteorological observations2. This made him think about the variations in time and geographical location of the surface pressure and its relation to the winds3. Already in a paper, possibly written before 1735, Hadley carried out an interesting and far-sighted discussion on the winds, which he found “of so uncertain and variable nature”: Hadley’s Principle 18 …concerning the Cause of the Trade-Winds, that for the same Cause the Motion of the Air will not be naturally in a great Circle, for any great Space upon the surface of the Earth anywhere, unless in the Equator itself, but in some other Line, and, in general, all Winds, as they come nearer the Equator will become more easterly, and as they recede from it, more and more westerly, unless some other Cause intervene4. -
Viscosity from Newton to Modern Non-Equilibrium Statistical Mechanics
Viscosity from Newton to Modern Non-equilibrium Statistical Mechanics S´ebastien Viscardy Belgian Institute for Space Aeronomy, 3, Avenue Circulaire, B-1180 Brussels, Belgium Abstract In the second half of the 19th century, the kinetic theory of gases has probably raised one of the most impassioned de- bates in the history of science. The so-called reversibility paradox around which intense polemics occurred reveals the apparent incompatibility between the microscopic and macroscopic levels. While classical mechanics describes the motionof bodies such as atoms and moleculesby means of time reversible equations, thermodynamics emphasizes the irreversible character of macroscopic phenomena such as viscosity. Aiming at reconciling both levels of description, Boltzmann proposed a probabilistic explanation. Nevertheless, such an interpretation has not totally convinced gen- erations of physicists, so that this question has constantly animated the scientific community since his seminal work. In this context, an important breakthrough in dynamical systems theory has shown that the hypothesis of microscopic chaos played a key role and provided a dynamical interpretation of the emergence of irreversibility. Using viscosity as a leading concept, we sketch the historical development of the concepts related to this fundamental issue up to recent advances. Following the analysis of the Liouville equation introducing the concept of Pollicott-Ruelle resonances, two successful approaches — the escape-rate formalism and the hydrodynamic-mode method — establish remarkable relationships between transport processes and chaotic properties of the underlying Hamiltonian dynamics. Keywords: statistical mechanics, viscosity, reversibility paradox, chaos, dynamical systems theory Contents 1 Introduction 2 2 Irreversibility 3 2.1 Mechanics. Energyconservationand reversibility . ........................ 3 2.2 Thermodynamics. -
Origin of the Solar System
Creation Myths The rise of the monotheistic religions changed this view. When one of the gods got a higher Old Myths status than others (who in some cases became Speculation about the origin and evolution of demons or devils), he continued to increase in the earth and the celestial bodies is probably as prestige and power until he became the Supreme old as human thinking. During the millennia that Lord, the undisputed ruler of the whole world. are covered by the history of science, philosphy, Then it was not enough for him to create the world and religion we can distinguish three types of ap in the sense of organizing a preexisting chaos; he proach to this problem. had to create it all from nothing (ex nihilo) by The first is the "theocratic-myth" approach, pronouncing a magic word or by his will power. according to which the evolution of the world was This is the meaning of "creation" when we use it governed by gods who once upon a time created today, but it is a relatively new concept. It was it. However, we must remember that the meaning generally accepted in Christianity in the second of "creation" has changed. The earliest meaning century A.D. but the Genesis description of the of this term seems to have been that the gods Creation seems to have either meaning. The crea brought order into a preexisting chaos. The world tion ex nihilo was not generally accepted by the was "ungenerated and indestructible"-as Aris philosophical-scientific community until the syn totle puts it-and the gods were part of this world thesis by St. -
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. -
Ages of Large Lunar Impact Craters and Implications for Bombardment During the Moon’S Middle Age ⇑ Michelle R
Icarus 225 (2013) 325–341 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Ages of large lunar impact craters and implications for bombardment during the Moon’s middle age ⇑ Michelle R. Kirchoff , Clark R. Chapman, Simone Marchi, Kristen M. Curtis, Brian Enke, William F. Bottke Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302, United States article info abstract Article history: Standard lunar chronologies, based on combining lunar sample radiometric ages with impact crater den- Received 20 October 2012 sities of inferred associated units, have lately been questioned about the robustness of their interpreta- Revised 28 February 2013 tions of the temporal dependance of the lunar impact flux. In particular, there has been increasing focus Accepted 10 March 2013 on the ‘‘middle age’’ of lunar bombardment, from the end of the Late Heavy Bombardment (3.8 Ga) until Available online 1 April 2013 comparatively recent times (1 Ga). To gain a better understanding of impact flux in this time period, we determined and analyzed the cratering ages of selected terrains on the Moon. We required distinct ter- Keywords: rains with random locations and areas large enough to achieve good statistics for the small, superposed Moon, Surface crater size–frequency distributions to be compiled. Therefore, we selected 40 lunar craters with diameter Cratering Impact processes 90 km and determined the model ages of their floors by measuring the density of superposed craters using the Lunar Reconnaissance Orbiter Wide Angle Camera mosaic. Absolute model ages were computed using the Model Production Function of Marchi et al.