The Origin and Timing of Fluvial Activity at Eberswalde Crater, Mars
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SPACE RESEARCH in POLAND Report to COMMITTEE
SPACE RESEARCH IN POLAND Report to COMMITTEE ON SPACE RESEARCH (COSPAR) 2020 Space Research Centre Polish Academy of Sciences and The Committee on Space and Satellite Research PAS Report to COMMITTEE ON SPACE RESEARCH (COSPAR) ISBN 978-83-89439-04-8 First edition © Copyright by Space Research Centre Polish Academy of Sciences and The Committee on Space and Satellite Research PAS Warsaw, 2020 Editor: Iwona Stanisławska, Aneta Popowska Report to COSPAR 2020 1 SATELLITE GEODESY Space Research in Poland 3 1. SATELLITE GEODESY Compiled by Mariusz Figurski, Grzegorz Nykiel, Paweł Wielgosz, and Anna Krypiak-Gregorczyk Introduction This part of the Polish National Report concerns research on Satellite Geodesy performed in Poland from 2018 to 2020. The activity of the Polish institutions in the field of satellite geodesy and navigation are focused on the several main fields: • global and regional GPS and SLR measurements in the frame of International GNSS Service (IGS), International Laser Ranging Service (ILRS), International Earth Rotation and Reference Systems Service (IERS), European Reference Frame Permanent Network (EPN), • Polish geodetic permanent network – ASG-EUPOS, • modeling of ionosphere and troposphere, • practical utilization of satellite methods in local geodetic applications, • geodynamic study, • metrological control of Global Navigation Satellite System (GNSS) equipment, • use of gravimetric satellite missions, • application of GNSS in overland, maritime and air navigation, • multi-GNSS application in geodetic studies. Report -
Placing World War I in the History of Mathematics David Aubin, Catherine Goldstein
Placing World War I in the History of Mathematics David Aubin, Catherine Goldstein To cite this version: David Aubin, Catherine Goldstein. Placing World War I in the History of Mathematics. 2013. hal- 00830121v1 HAL Id: hal-00830121 https://hal.sorbonne-universite.fr/hal-00830121v1 Preprint submitted on 4 Jun 2013 (v1), last revised 8 Jul 2014 (v2) HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Placing World War I in the History of Mathematics David Aubin and Catherine Goldstein Abstract. In the historical literature, opposite conclusions were drawn about the impact of the First World War on mathematics. In this chapter, the case is made that the war was an important event for the history of mathematics. We show that although mathematicians' experience of the war was extremely varied, its impact was decisive on the life of a great number of them. We present an overview of some uses of mathematics in war and of the development of mathematics during the war. We conclude by arguing that the war also was a crucial factor in the institutional modernization of mathematics. Les vrais adversaires, dans la guerre d'aujourd'hui, ce sont les professeurs de math´ematiques`aleur table, les physiciens et les chimistes dans leur laboratoire. -
Tentative Lists Submitted by States Parties As of 15 April 2021, in Conformity with the Operational Guidelines
World Heritage 44 COM WHC/21/44.COM/8A Paris, 4 June 2021 Original: English UNITED NATIONS EDUCATIONAL, SCIENTIFIC AND CULTURAL ORGANIZATION CONVENTION CONCERNING THE PROTECTION OF THE WORLD CULTURAL AND NATURAL HERITAGE WORLD HERITAGE COMMITTEE Extended forty-fourth session Fuzhou (China) / Online meeting 16 – 31 July 2021 Item 8 of the Provisional Agenda: Establishment of the World Heritage List and of the List of World Heritage in Danger 8A. Tentative Lists submitted by States Parties as of 15 April 2021, in conformity with the Operational Guidelines SUMMARY This document presents the Tentative Lists of all States Parties submitted in conformity with the Operational Guidelines as of 15 April 2021. • Annex 1 presents a full list of States Parties indicating the date of the most recent Tentative List submission. • Annex 2 presents new Tentative Lists (or additions to Tentative Lists) submitted by States Parties since 16 April 2019. • Annex 3 presents a list of all sites included in the Tentative Lists of the States Parties to the Convention, in alphabetical order. Draft Decision: 44 COM 8A, see point II I. EXAMINATION OF TENTATIVE LISTS 1. The World Heritage Convention provides that each State Party to the Convention shall submit to the World Heritage Committee an inventory of the cultural and natural sites situated within its territory, which it considers suitable for inscription on the World Heritage List, and which it intends to nominate during the following five to ten years. Over the years, the Committee has repeatedly confirmed the importance of these Lists, also known as Tentative Lists, for planning purposes, comparative analyses of nominations and for facilitating the undertaking of global and thematic studies. -
Formation of Gullies on Mars: Link to Recent Climate History and Insolation Microenvironments Implicate Surface Water Flow Origin
Formation of gullies on Mars: Link to recent climate history and insolation microenvironments implicate surface water flow origin James W. Head*†, David R. Marchant‡, and Mikhail A. Kreslavsky*§ *Department of Geological Sciences, Brown University, Providence, RI 02912; ‡Department of Earth Sciences, Boston University, Boston, MA 02215; and §Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064 Edited by John Imbrie, Brown University, Providence, RI, and approved July 18, 2008 (received for review April 17, 2008) Features seen in portions of a typical midlatitude Martian impact provide a context and framework of information in which their crater show that gully formation follows a geologically recent origin might be better understood. Assessment of the stratigraphic period of midlatitude glaciation. Geological evidence indicates relationships in a crater interior typical of many gully occurrences that, in the relatively recent past, sufficient snow and ice accumu- provides evidence that gully formation is linked to glaciation and to lated on the pole-facing crater wall to cause glacial flow and filling geologically recent climate change that provided conditions for of the crater floor with debris-covered glaciers. As glaciation snow/ice accumulation and top-down melting. waned, debris-covered glaciers ceased flowing, accumulation The distribution of gullies shows a latitudinal dependence on zones lost ice, and newly exposed wall alcoves continued as the Mars, exclusively poleward of 30° in each hemisphere (2, 14) with location for limited snow/frost deposition, entrapment, and pres- a distinct concentration in the 30–50° latitude bands (e.g., 2, 7, ervation. Analysis of the insolation geometry of this pole-facing 8, 14, 18). -
MARS DURING the PRE-NOACHIAN. J. C. Andrews-Hanna1 and W. B. Bottke2, 1Lunar and Planetary La- Boratory, University of Arizona
Fourth Conference on Early Mars 2017 (LPI Contrib. No. 2014) 3078.pdf MARS DURING THE PRE-NOACHIAN. J. C. Andrews-Hanna1 and W. B. Bottke2, 1Lunar and Planetary La- boratory, University of Arizona, Tucson, AZ 85721, [email protected], 2Southwest Research Institute and NASA’s SSERVI-ISET team, 1050 Walnut St., Suite 300, Boulder, CO 80302. Introduction: The surface geology of Mars appar- ing the pre-Noachian was ~10% of that during the ently dates back to the beginning of the Early Noachi- LHB. Consideration of the sawtooth-shaped exponen- an, at ~4.1 Ga, leaving ~400 Myr of Mars’ earliest tially declining impact fluxes both in the aftermath of evolution effectively unconstrained [1]. However, an planet formation and during the Late Heavy Bom- enduring record of the earlier pre-Noachian conditions bardment [5] suggests that the impact flux during persists in geophysical and mineralogical data. We use much of the pre-Noachian was even lower than indi- geophysical evidence, primarily in the form of the cated above. This bombardment history is consistent preservation of the crustal dichotomy boundary, to- with a late heavy bombardment (LHB) of the inner gether with mineralogical evidence in order to infer the Solar System [6] during which HUIA formed, which prevailing surface conditions during the pre-Noachian. followed the planet formation era impacts during The emerging picture is a pre-Noachian Mars that was which the dichotomy formed. less dynamic than Noachian Mars in terms of impacts, Pre-Noachian Tectonism and Volcanism: The geodynamics, and hydrology. crust within each of the southern highlands and north- Pre-Noachian Impacts: We define the pre- ern lowlands is remarkably uniform in thickness, aside Noachian as the time period bounded by two impacts – from regions in which it has been thickened by volcan- the dichotomy-forming impact and the Hellas-forming ism (e.g., Tharsis, Elysium) or thinned by impacts impact. -
Mawrth Vallis, Mars: a Fascinating Place for Future in Situ Exploration
Mawrth Vallis, Mars: a fascinating place for future in situ exploration François Poulet1, Christoph Gross2, Briony Horgan3, Damien Loizeau1, Janice L. Bishop4, John Carter1, Csilla Orgel2 1Institut d’Astrophysique Spatiale, CNRS/Université Paris-Sud, 91405 Orsay Cedex, France 2Institute of Geological Sciences, Planetary Sciences and Remote Sensing Group, Freie Universität Berlin, Germany 3Purdue University, West Lafayette, USA. 4SETI Institute/NASA-ARC, Mountain View, CA, USA Corresponding author: François Poulet, IAS, Bâtiment 121, CNRS/Université Paris-Sud, 91405 Orsay Cedex, France; email: [email protected] Running title: Mawrth: a fascinating place for exploration 1 Abstract After the successful landing of the Mars Science Laboratory rover, both NASA and ESA initiated a selection process for potential landing sites for the Mars2020 and ExoMars missions, respectively. Two ellipses located in the Mawrth Vallis region were proposed and evaluated during a series of meetings (3 for Mars2020 mission and 5 for ExoMars). We describe here the regional context of the two proposed ellipses as well as the framework of the objectives of these two missions. Key science targets of the ellipses and their astrobiological interests are reported. This work confirms the proposed ellipses contain multiple past Martian wet environments of subaerial, subsurface and/or subaqueous character, in which to probe the past climate of Mars, build a broad picture of possible past habitable environments, evaluate their exobiological potentials and search for biosignatures in well-preserved rocks. A mission scenario covering several key investigations during the nominal mission of each rover is also presented, as well as descriptions of how the site fulfills the science requirements and expectations of in situ martian exploration. -
Review of the MEPAG Report on Mars Special Regions
THE NATIONAL ACADEMIES PRESS This PDF is available at http://nap.edu/21816 SHARE Review of the MEPAG Report on Mars Special Regions DETAILS 80 pages | 8.5 x 11 | PAPERBACK ISBN 978-0-309-37904-5 | DOI 10.17226/21816 CONTRIBUTORS GET THIS BOOK Committee to Review the MEPAG Report on Mars Special Regions; Space Studies Board; Division on Engineering and Physical Sciences; National Academies of Sciences, Engineering, and Medicine; European Space Sciences Committee; FIND RELATED TITLES European Science Foundation Visit the National Academies Press at NAP.edu and login or register to get: – Access to free PDF downloads of thousands of scientific reports – 10% off the price of print titles – Email or social media notifications of new titles related to your interests – Special offers and discounts Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the National Academies Press. (Request Permission) Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved. Review of the MEPAG Report on Mars Special Regions Committee to Review the MEPAG Report on Mars Special Regions Space Studies Board Division on Engineering and Physical Sciences European Space Sciences Committee European Science Foundation Strasbourg, France Copyright National Academy of Sciences. All rights reserved. Review of the MEPAG Report on Mars Special Regions THE NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001 This study is based on work supported by the Contract NNH11CD57B between the National Academy of Sciences and the National Aeronautics and Space Administration and work supported by the Contract RFP/IPL-PTM/PA/fg/306.2014 between the European Science Foundation and the European Space Agency. -
IN-SITU RADIOMETRIC AGE DETERMINATION: a CRITICAL COMPONENT of MARS EXPLORATION. J. B. Plescia1 and T. D. Swindle2, 1Applied
Seventh International Conference on Mars 3278.pdf IN-SITU RADIOMETRIC AGE DETERMINATION: A CRITICAL COMPONENT OF MARS EXPLORATION. J. B. Plescia1 and T. D. Swindle2, 1Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723, [email protected]. 2Department of Planetary Sciences, Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, [email protected]. Introduction: In order to understand the geologic, Bombardment [12-18], although this remains a contro- climatic and possibly the biologic evolution of Mars, versial topic. It has also been suggested that the crater- the absolute timing of events must be established. ing rate over the last several billion years has not been Questions of climate change, glacial processes, avail- uniform, but rather has been punctuated by periodic ability of surface water, recent volcanism, and atmos- spikes in the rate [19-20]. pheric evolution all hinge on determining when those events occurred in absolute time. Resolving the abso- lute timing of events has become even more critical with the suggestions of currently active glacial and perhaps fluvial activity and very young volcanic activ- ity. Background: To date, only the relative chronology of events has been firmly established [1]. This has been accomplished through the use of impact crater counts in which the frequency of impact craters per unit area greater than or equal to some diameter is used as a reference for comparison among surfaces; the higher the frequency, the older the age [2-3]. This technique allows surfaces and events on different parts of a planet to be correlated in time. -
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. -
11 Fall Unamagazine
FALL 2011 • VOLUME 19 • No. 3 FOR ALUMNI AND FRIENDS OF THE UNIVERSITY OF NORTH ALABAMA Cover Story 10 ..... Thanks a Million, Harvey Robbins Features 3 ..... The Transition 14 ..... From Zero to Infinity 16 ..... Something Special 20 ..... The Sounds of the Pride 28 ..... Southern Laughs 30 ..... Academic Affairs Awards 33 ..... Excellence in Teaching Award 34 ..... China 38 ..... Words on the Breeze Departments 2 ..... President’s Message 6 ..... Around the Campus 45 ..... Class Notes 47 ..... In Memory FALL 2011 • VOLUME 19 • No. 3 for alumni and friends of the University of North Alabama president’s message ADMINISTRATION William G. Cale, Jr. President William G. Cale, Jr. The annual everyone to attend one of these. You may Vice President for Academic Affairs/Provost Handy festival contact Dr. Alan Medders (Vice President John Thornell is drawing large for Advancement, [email protected]) Vice President for Business and Financial Affairs crowds to the many or Mr. Mark Linder (Director of Athletics, Steve Smith venues where music [email protected]) for information or to Vice President for Student Affairs is being played. At arrange a meeting for your group. David Shields this time of year Sometimes we measure success by Vice President for University Advancement William G. Cale, Jr. it is impossible the things we can see, like a new building. Alan Medders to go anywhere More often, though, success happens one Vice Provost for International Affairs in town and not hear music. The festival student at a time as we provide more and Chunsheng Zhang is also a reminder that we are less than better educational opportunities. -
Discrete Element Modelling of Pit Crater Formation on Mars
geosciences Article Discrete Element Modelling of Pit Crater Formation on Mars Stuart Hardy 1,2 1 ICREA (Institució Catalana de Recerca i Estudis Avançats), Passeig Lluís Companys 23, 08010 Barcelona, Spain; [email protected]; Tel.: +34-934-02-13-76 2 Departament de Dinàmica de la Terra i de l’Oceà, Facultat de Ciències de la Terra, Universitat de Barcelona, C/Martí i Franqués s/n, 08028 Barcelona, Spain Abstract: Pit craters are now recognised as being an important part of the surface morphology and structure of many planetary bodies, and are particularly remarkable on Mars. They are thought to arise from the drainage or collapse of a relatively weak surficial material into an open (or widening) void in a much stronger material below. These craters have a very distinctive expression, often presenting funnel-, cone-, or bowl-shaped geometries. Analogue models of pit crater formation produce pits that typically have steep, nearly conical cross sections, but only show the surface expression of their initiation and evolution. Numerical modelling studies of pit crater formation are limited and have produced some interesting, but nonetheless puzzling, results. Presented here is a high-resolution, 2D discrete element model of weak cover (regolith) collapse into either a static or a widening underlying void. Frictional and frictional-cohesive discrete elements are used to represent a range of probable cover rheologies. Under Martian gravitational conditions, frictional-cohesive and frictional materials both produce cone- and bowl-shaped pit craters. For a given cover thickness, the specific crater shape depends on the amount of underlying void space created for drainage. -
Downselection of Landing Sites Proposed for the Mars 2020 Rover Mission
47th Lunar and Planetary Science Conference (2016) 2324.pdf DOWNSELECTION OF LANDING SITES PROPOSED FOR THE MARS 2020 ROVER MISSION. M. P. Golombek1, J. A. Grant2, K. A. Farley3, K. Williford1, A. Chen1, R. E. Otero1, and J. W. Ashley1, 1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; 2Smithsonian Institution, Center for Earth and Planetary Sciences, Washington, D.C. 20560, 3Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125. Introduction: The Mars 2020 mission would ex- suitable for addressing key planetary evolution ques- plore a site likely to have been habitable, seek signs of tions if and when they are returned to Earth. past life, prepare a returnable cache with the most Results of the voting were presented as the compelling samples, take the first steps towards in-situ weighted average (assigning 5 points to each green resource utilization on Mars, and demonstrate technol- vote, 3 to each yellow vote, and 1 to each red vote that ogy needed for future human and robotic exploration were then summed and divided by the total number of of Mars. The first landing site workshop identified and votes) and the mode (color receiving the most votes). prioritized 27 landing sites proposed by the science This ensured that participants could not skew the re- community according to science objectives that also sults by withholding votes from some sites. Both met the engineering constraints [1]. This abstract de- methods yield similar results and reveal a fall-off in scribes the downselection of landing sites that occurred support for sites ranked lower than the top nine or ten at the second landing site workshop and associated based on mode and average, respectively [2].