Newsletter 105 ª June 2001 NEWSLETTER
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CENTAURI II Benutzerhandbuch
CENTAURI II Benutzerhandbuch SW-Version ab 3.1.0.73 MAYAH, CENTAURI, FLASHCAST sind eingetragene Warenzeichen. Alle anderen verwendeten Warenzeichen werden hiermit anerkannt. CENTAURI II Benutzerhandbuch ab SW 3.1.0.73 Bestell-Nr. CIIUM001 Stand 11/2005 (c) Copyright by MAYAH Communications GmbH Die Vervielfältigung des vorliegenden Handbuches, sowie der darin besprochenen Dokumentationen aus dem Internet, auch nur auszugsweise, ist nur mit ausdrücklicher schriftlicher Genehmigung der MAYAH Communications GmbH erlaubt. 1 Einführung ........................................................................................................... 1 1.1 Vorwort......................................................................................................... 1 1.2 Einbau / Installation ...................................................................................... 2 1.3 Lieferumfang ................................................................................................ 2 1.4 Umgebungs- / Betriebsbedingung................................................................ 2 1.5 Anschlüsse................................................................................................... 3 2 Verbindungsaufbau ............................................................................................. 4 2.1 ISDN Verbindungen mit dem Centauri II ...................................................... 4 2.1.1 FlashCast Technologie und Audiocodec Kategorien............................. 4 2.1.2 Wie bekomme ich eine synchronisierte Verbindung -
Ira Sprague Bowen Papers, 1940-1973
http://oac.cdlib.org/findaid/ark:/13030/tf2p300278 No online items Inventory of the Ira Sprague Bowen Papers, 1940-1973 Processed by Ronald S. Brashear; machine-readable finding aid created by Gabriela A. Montoya Manuscripts Department The Huntington Library 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2203 Fax: (626) 449-5720 Email: [email protected] URL: http://www.huntington.org/huntingtonlibrary.aspx?id=554 © 1998 The Huntington Library. All rights reserved. Observatories of the Carnegie Institution of Washington Collection Inventory of the Ira Sprague 1 Bowen Papers, 1940-1973 Observatories of the Carnegie Institution of Washington Collection Inventory of the Ira Sprague Bowen Paper, 1940-1973 The Huntington Library San Marino, California Contact Information Manuscripts Department The Huntington Library 1151 Oxford Road San Marino, California 91108 Phone: (626) 405-2203 Fax: (626) 449-5720 Email: [email protected] URL: http://www.huntington.org/huntingtonlibrary.aspx?id=554 Processed by: Ronald S. Brashear Encoded by: Gabriela A. Montoya © 1998 The Huntington Library. All rights reserved. Descriptive Summary Title: Ira Sprague Bowen Papers, Date (inclusive): 1940-1973 Creator: Bowen, Ira Sprague Extent: Approximately 29,000 pieces in 88 boxes Repository: The Huntington Library San Marino, California 91108 Language: English. Provenance Placed on permanent deposit in the Huntington Library by the Observatories of the Carnegie Institution of Washington Collection. This was done in 1989 as part of a letter of agreement (dated November 5, 1987) between the Huntington and the Carnegie Observatories. The papers have yet to be officially accessioned. Cataloging of the papers was completed in 1989 prior to their transfer to the Huntington. -
Supplementary Information For
Supplementary Information for Vertical Angular Momentum Constraint on Lunar Formation and Orbital History ZhenLiang Tian and Jack Wisdom Z. Tian, J. Wisdom E-mail: [email protected], [email protected] This PDF file includes: Supplementary text Figs. S1 to S4 Table S1 References for SI reference citations www.pnas.org/cgi/doi/10.1073/pnas.2003496117 ZhenLiang Tian and Jack Wisdom 1 of 11 Supporting Information Text Model Comparison. Our model, which is the same as in (1), differs from the model of (2) in the following aspects: 1. Probably the most important difference is the tidal model. We use the conventional Darwin-Kaula constant Q model (3). In this model the tidal potential is expanded in a Fourier series and the response to each term is given a phase delay to model dissipation, by analogy to the damped harmonic oscillator. The explicit form builds in considerable constraints from orbital mechanics. There is little observational evidence to constrain the phase delays, but results from the analysis of lunar laser ranging (LLR) data are consistent with the Darwin-Kaula choice to set all the phase delays to be equal (4). Ćuk et al. (2) stated that there is a problem with the constant Q model: that it predicts a decay of orbital eccentricity that, to leading order, is independent of eccentricity. However, this is not true. Using the expressions in (3), one can show that the constant Q model gives a decay of eccentricity that is, to leading order, proportional to eccentricity. Nevertheless, given this misunderstanding of the constant Q model, Ćuk et al. -
Breakthrough Propulsion Study Assessing Interstellar Flight Challenges and Prospects
Breakthrough Propulsion Study Assessing Interstellar Flight Challenges and Prospects NASA Grant No. NNX17AE81G First Year Report Prepared by: Marc G. Millis, Jeff Greason, Rhonda Stevenson Tau Zero Foundation Business Office: 1053 East Third Avenue Broomfield, CO 80020 Prepared for: NASA Headquarters, Space Technology Mission Directorate (STMD) and NASA Innovative Advanced Concepts (NIAC) Washington, DC 20546 June 2018 Millis 2018 Grant NNX17AE81G_for_CR.docx pg 1 of 69 ABSTRACT Progress toward developing an evaluation process for interstellar propulsion and power options is described. The goal is to contrast the challenges, mission choices, and emerging prospects for propulsion and power, to identify which prospects might be more advantageous and under what circumstances, and to identify which technology details might have greater impacts. Unlike prior studies, the infrastructure expenses and prospects for breakthrough advances are included. This first year's focus is on determining the key questions to enable the analysis. Accordingly, a work breakdown structure to organize the information and associated list of variables is offered. A flow diagram of the basic analysis is presented, as well as more detailed methods to convert the performance measures of disparate propulsion methods into common measures of energy, mass, time, and power. Other methods for equitable comparisons include evaluating the prospects under the same assumptions of payload, mission trajectory, and available energy. Missions are divided into three eras of readiness (precursors, era of infrastructure, and era of breakthroughs) as a first step before proceeding to include comparisons of technology advancement rates. Final evaluation "figures of merit" are offered. Preliminary lists of mission architectures and propulsion prospects are provided. -
The Chaotic Rotation of Hyperion*
ICARUS 58, 137-152 (1984) The Chaotic Rotation of Hyperion* JACK WISDOM AND STANTON J. PEALE Department of Physics, University of California, Santa Barbara, California 93106 AND FRANGOIS MIGNARD Centre d'Etudes et de Recherehes G~odynamique et Astronomique, Avenue Copernic, 06130 Grasse, France Received August 22, 1983; revised November 4, 1983 A plot of spin rate versus orientation when Hyperion is at the pericenter of its orbit (surface of section) reveals a large chaotic zone surrounding the synchronous spin-orbit state of Hyperion, if the satellite is assumed to be rotating about a principal axis which is normal to its orbit plane. This means that Hyperion's rotation in this zone exhibits large, essentially random variations on a short time scale. The chaotic zone is so large that it surrounds the 1/2 and 2 states, and libration in the 3/2 state is not possible. Stability analysis shows that for libration in the synchronous and 1/2 states, the orientation of the spin axis normal to the orbit plane is unstable, whereas rotation in the 2 state is attitude stable. Rotation in the chaotic zone is also attitude unstable. A small deviation of the principal axis from the orbit normal leads to motion through all angles in both the chaotic zone and the attitude unstable libration regions. Measures of the exponential rate of separation of nearby trajectories in phase space (Lyapunov characteristic exponents) for these three-dimensional mo- tions indicate the the tumbling is chaotic and not just a regular motion through large angles. As tidal dissipation drives Hyperion's spin toward a nearly synchronous value, Hyperion necessarily enters the large chaotic zone. -
Table of Contents
AAS Newsletter September/October 2012, Issue 166 - Published for the Members of the American Astronomical Society Table of Contents 2 President’s Column 17 Committee on the Status of Women in 4 From the Executive Office Astronomy 5 What Makes an Astronomy Story 18 News from NSF Division of Astronomical Newsworthy? Sciences (AST) 6 Journals Update 20 JWST Update 9 Secretary's Corner 21 HAD News 9 Council Actions 21 Honored Elsewhere 10 The AAS Heeds the Call of the Wild 22 Announcements 16 Committee on Employment 23 Calendar of Events 25 Washington News A A S American Astronomical Society AAS Officers President's Column David J. Helfand, President Debra M. Elmegreen, Past President David J. Helfand, [email protected] Nicholas B. Suntzeff, Vice-President Edward B. Churchwell, Vice-President Paula Szkody, Vice-President Hervey (Peter) Stockman, Treasurer G. Fritz Benedict, Secretary Anne P. Cowley, Publications Board Chair Edward E. Prather, Education Officer At 1:32AM Eastern time on 6 Councilors August, the Mars Science Laboratory Bruce Balick Nancy S. Brickhouse and its charmingly named rover, Eileen D. Friel Curiosity, executed a perfect landing Edward F. Guinan Todd J. Henry in Gale Crater. President Obama Steven D. Kawaler called the highly complex landing Patricia Knezek Robert Mathieu procedure “an unprecedented feat of Angela Speck technology that will stand as a point Executive Office Staff of pride far into the future.” While Kevin B. Marvel, Executive Officer we certainly hope Curiosity’s lifetime Tracy Beale, Registrar & Meeting Coordinator Chris Biemesderfer, Director of Publishing on Mars is a long one, we must all Sherri Brown, Membership Services continue to make the case that we Coordinator Kelly E. -
Gravity's Fatal Attraction
Cambridge University Press 978-0-521-71793-9 - Gravity’s Fatal Attraction: Black Holes in the Universe, Second Edition Mitchell Begelman and Martin Rees Frontmatter More information GRAVITY’S FATAL ATTRACTION Black Holes in the Universe Second edition Richly illustrated with the images from observatories on the ground and in space, and computer simulations, this book shows how black holes were discovered, and discusses our current understanding of their role in cosmic evolution. This second edition covers new discoveries made in the past decade, including defi nitive proof of a black hole at the center of the Milky Way, evidence that the expansion of the Universe is accelerating, and the new appreciation of the connection between black holes and galaxy formation. There are entirely new chapters on gamma-ray bursts and cosmic feedback. Begelman and Rees blend theoretical arguments with observa- tional results to demonstrate how both have contributed to the subject. Clear, explanatory illustrations and photographs reveal the strange and amazing workings of our Universe. The engaging style makes this book suitable for introductory undergraduate courses, amateur astronomers, and all readers interested in astronomy and physics. Mitchell Begelman is Chairman of the Department of Astrophysical and Planetary Sciences and Fellow of JILA, at the University of Colorado at Boulder. He has won several awards, including the Guggenheim Fel- lowship, Sloan Research Fellowship, and the American Astronomical Society Warner Prize. Martin Rees is Professor of Cosmology and Astrophysics and Master of Trinity College at Cambridge University, and Astronomer Royal. He is a winner of the Gold Medal of the Royal Astronomical Society and other awards. -
10. Scientific Programme 10.1
10. SCIENTIFIC PROGRAMME 10.1. OVERVIEW (a) Invited Discourses Plenary Hall B 18:00-19:30 ID1 “The Zoo of Galaxies” Karen Masters, University of Portsmouth, UK Monday, 20 August ID2 “Supernovae, the Accelerating Cosmos, and Dark Energy” Brian Schmidt, ANU, Australia Wednesday, 22 August ID3 “The Herschel View of Star Formation” Philippe André, CEA Saclay, France Wednesday, 29 August ID4 “Past, Present and Future of Chinese Astronomy” Cheng Fang, Nanjing University, China Nanjing Thursday, 30 August (b) Plenary Symposium Review Talks Plenary Hall B (B) 8:30-10:00 Or Rooms 309A+B (3) IAUS 288 Astrophysics from Antarctica John Storey (3) Mon. 20 IAUS 289 The Cosmic Distance Scale: Past, Present and Future Wendy Freedman (3) Mon. 27 IAUS 290 Probing General Relativity using Accreting Black Holes Andy Fabian (B) Wed. 22 IAUS 291 Pulsars are Cool – seriously Scott Ransom (3) Thu. 23 Magnetars: neutron stars with magnetic storms Nanda Rea (3) Thu. 23 Probing Gravitation with Pulsars Michael Kremer (3) Thu. 23 IAUS 292 From Gas to Stars over Cosmic Time Mordacai-Mark Mac Low (B) Tue. 21 IAUS 293 The Kepler Mission: NASA’s ExoEarth Census Natalie Batalha (3) Tue. 28 IAUS 294 The Origin and Evolution of Cosmic Magnetism Bryan Gaensler (B) Wed. 29 IAUS 295 Black Holes in Galaxies John Kormendy (B) Thu. 30 (c) Symposia - Week 1 IAUS 288 Astrophysics from Antartica IAUS 290 Accretion on all scales IAUS 291 Neutron Stars and Pulsars IAUS 292 Molecular gas, Dust, and Star Formation in Galaxies (d) Symposia –Week 2 IAUS 289 Advancing the Physics of Cosmic -
Dirk Brouwer
NATIONAL ACADEMY OF SCIENCES D I R K B R O U W ER 1902—1966 A Biographical Memoir by G . M . C LEMENCE Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1970 NATIONAL ACADEMY OF SCIENCES WASHINGTON D.C. DIRK BROUWER September 1, 1902-January 31, 1966 BY G. M. CLEMENCE IRK BROUWER, who contributed more to dynamical astron- D omy than any other astronomer of his time, died on January 31, 1966, after a week in hospital; his death was occa- sioned by an acute disorder of the heart. He is survived by his widow and an only son, James. Brouwer was born in Rotterdam, the Netherlands, on September 1, 1902, the son of a civil service employee. As a stu- dent in the University of Leiden he studied mathematics and astronomy, coming under the influence of Willem de Sitter, who in his own day was the dean of that branch of astronomy in which Brouwer was to do most of his work. Receiving the Ph.D. degree in 1927 under de Sitter, Brouwer came to the United States as a fellow of the International Education Board, spending a year at the University of California in Berkeley and at Yale University, where he was to remain the rest of his life. His initial appointment at Yale was in 1928 as research as- sistant to Ernest W. Brown, who was then the greatest living authority on the motion of the moon. -
Variable Star Classification and Light Curves Manual
Variable Star Classification and Light Curves An AAVSO course for the Carolyn Hurless Online Institute for Continuing Education in Astronomy (CHOICE) This is copyrighted material meant only for official enrollees in this online course. Do not share this document with others. Please do not quote from it without prior permission from the AAVSO. Table of Contents Course Description and Requirements for Completion Chapter One- 1. Introduction . What are variable stars? . The first known variable stars 2. Variable Star Names . Constellation names . Greek letters (Bayer letters) . GCVS naming scheme . Other naming conventions . Naming variable star types 3. The Main Types of variability Extrinsic . Eclipsing . Rotating . Microlensing Intrinsic . Pulsating . Eruptive . Cataclysmic . X-Ray 4. The Variability Tree Chapter Two- 1. Rotating Variables . The Sun . BY Dra stars . RS CVn stars . Rotating ellipsoidal variables 2. Eclipsing Variables . EA . EB . EW . EP . Roche Lobes 1 Chapter Three- 1. Pulsating Variables . Classical Cepheids . Type II Cepheids . RV Tau stars . Delta Sct stars . RR Lyr stars . Miras . Semi-regular stars 2. Eruptive Variables . Young Stellar Objects . T Tau stars . FUOrs . EXOrs . UXOrs . UV Cet stars . Gamma Cas stars . S Dor stars . R CrB stars Chapter Four- 1. Cataclysmic Variables . Dwarf Novae . Novae . Recurrent Novae . Magnetic CVs . Symbiotic Variables . Supernovae 2. Other Variables . Gamma-Ray Bursters . Active Galactic Nuclei 2 Course Description and Requirements for Completion This course is an overview of the types of variable stars most commonly observed by AAVSO observers. We discuss the physical processes behind what makes each type variable and how this is demonstrated in their light curves. Variable star names and nomenclature are placed in a historical context to aid in understanding today’s classification scheme. -
NEWSLETI'er September-October 1987 PRESIDENT's REPORT Although I Am Writing This Report in the Dog Days of Summer, Most of Us Wi
Volume 17, Number 5 NEWSLETI'ER September-October 1987 PRESIDENT'S REPORT Although I am writing this report in the dog days of summer, most of us will be back to the rigors of our respective positions by the time this Newsletter appears. For many mathematicians, fall carries the additional responsibility of preparing grant proposals (I understand there are some very organized individuals who do this in the summer). I urge our women and minority members to bear in mind the many grants available through the ROW (Research Opportunities for Women) and Minority programs at the National Science Foundation. A thorough description of these opportunities is given in the article by Louise Raphael in this Newsletter (May-June 1987). One of the most attractive of the NSF offerings is the Visiting Professorships for Women program. I have spoken to many women who have received this grant or applied for it, and was surprised to learn that there is a wide variety of opinion regarding its efficacy. If you have had experience with this grant or have an opinion about the concept, I would appreciate hearing your views. While on the subject of the NSF, I would like to take this opportunity to wish Dr. Kenneth Gross, who has been the Program Director for Modern Analysis for the past two years, best of luck as he leaves NSF for the University of Vermont. Dr. Gross has been a strong supporter of women and minority mathematicians while at NSF, and many women have commented on the encouragement he has given them. * Linda Keen and I have written to the Notices regarding the lack of women speakers at the symposium on the mathematical heritage of Hermann Weyl at Duke University (see August Notices, Letters to the Editor). -
Nd AAS Meeting Abstracts
nd AAS Meeting Abstracts 101 – Kavli Foundation Lectureship: The Outreach Kepler Mission: Exoplanets and Astrophysics Search for Habitable Worlds 200 – SPD Harvey Prize Lecture: Modeling 301 – Bridging Laboratory and Astrophysics: 102 – Bridging Laboratory and Astrophysics: Solar Eruptions: Where Do We Stand? Planetary Atoms 201 – Astronomy Education & Public 302 – Extrasolar Planets & Tools 103 – Cosmology and Associated Topics Outreach 303 – Outer Limits of the Milky Way III: 104 – University of Arizona Astronomy Club 202 – Bridging Laboratory and Astrophysics: Mapping Galactic Structure in Stars and Dust 105 – WIYN Observatory - Building on the Dust and Ices 304 – Stars, Cool Dwarfs, and Brown Dwarfs Past, Looking to the Future: Groundbreaking 203 – Outer Limits of the Milky Way I: 305 – Recent Advances in Our Understanding Science and Education Overview and Theories of Galactic Structure of Star Formation 106 – SPD Hale Prize Lecture: Twisting and 204 – WIYN Observatory - Building on the 308 – Bridging Laboratory and Astrophysics: Writhing with George Ellery Hale Past, Looking to the Future: Partnerships Nuclear 108 – Astronomy Education: Where Are We 205 – The Atacama Large 309 – Galaxies and AGN II Now and Where Are We Going? Millimeter/submillimeter Array: A New 310 – Young Stellar Objects, Star Formation 109 – Bridging Laboratory and Astrophysics: Window on the Universe and Star Clusters Molecules 208 – Galaxies and AGN I 311 – Curiosity on Mars: The Latest Results 110 – Interstellar Medium, Dust, Etc. 209 – Supernovae and Neutron