DOCSLIB.ORG

Report of the Astronomy and Astrophysics, April 26, 2019

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

April 28, 2019 Dr. France A. Córdova, Director National Science Foundation 2415 Eisenhower Avenue, Suite 19000 Alexandria, VA 22314 Mr. James Bridenstine, Administrator Office of the Administrator NASA Headquarters Washington, DC 20546-0001 Mr. Richard Perry, Secretary of Energy U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 The Honorable Eddie Bernice Johnson, Chairwoman Committee on Science, Space and Technology United States House of Representatives Washington, DC 20515 The Honorable Roger Wicker, Chairman Committee on Commerce, Science and Transportation United States Senate Washington, DC 20510 The Honorable Lamar Alexander, Chairman Committee on Health, Education, Labor & Pensions United States Senate Washington, DC 20510 Headquarters: 65-1120 Mamalahoa Highway, Kamuela, HI 96743 Phone (808) 885-7887 l Fax (808) 885-4464 Dear Dr. Córdova, Mr. Bridenstine, Secretary Perry, Chairwoman Johnson, Chairman Wicker, and Chairman Alexander: I am pleased to transmit to you the annual report of the Astronomy and Astrophysics Advisory Committee for 2018. As you are aware, this year’s report was delayed due to the partial government shutdown early in 2019. The Committee thanks you for your patience, and apologizes for the delay in sending the report. The Astronomy and Astrophysics Advisory Committee was established under the National Science Foundation Authorization Act of 2002 Public Law 107-368 to: (1) assess, and make recommendations regarding, the coordination of astronomy and astrophysics programs of the Foundation and the National Aeronautics and Space Administration, and the Department of Energy; (2) assess, and make recommendations regarding, the status of the activities of the Foundation and the National Aeronautics and Space Administration, and the Department of Energy as they relate to the recommendations contained in the National Research Council's 2010 report entitled New Worlds, New Horizons in Astronomy and Astrophysics, and the recommendations contained in subsequent National Research Council reports of a similar nature; (3) not later than March 15 of each year, transmit a report to the Director, the Administrator of the National Aeronautics and Space Administration, the Secretary of Energy, the Committee on Commerce, Science and Transportation of the United States Senate, the Committee on Energy and Natural Resources of the United States Senate, and the Committee on Science, Space, and Technology of the United States House of Representatives, on the Advisory Committee's findings and recommendations under paragraphs (1) and (2). The attached document is the sixteenth such report. The executive summary is followed by the report, with findings and recommendations for NSF, NASA and DOE regarding their support of the nation’s astronomy and astrophysics research enterprise, along with detailed recommendations concerning specific projects and programs. If there are any matters your offices would like AAAC input on in addition to this report, I would be glad to provide you with a personal briefing. Sincerely yours, on behalf of the Committee, Dr. John O’Meara Chair, Astronomy and Astrophysics Advisory Committee cc: Representative Frank Lucas, Ranking Member, Committee on Science, Space, and Technology, United States House of Representatives Senator Maria Cantwell, Ranking Member, Committee on Commerce, Science and Transportation, United States Senate Senator Patty Murray, Ranking Member, Committee on Health, Education, Labor & Pensions, United States Senate Senator Jerry Moran, Chairman, Subcommittee on Commerce, Justice, Science, and Related Agencies, Committee on Appropriations, United States Senate Senator Jeanne Shaheen, Ranking Member, Subcommittee on Commerce, Justice, Science, and Related Agencies, Committee on Appropriations, United States Senate Senator Lisa Murkowski, Chairwoman, Committee on Energy & Natural Resources, United States Senate Senator Joseph Manchin, Ranking Member, Committee on Energy & Natural Resources, United States Senate Representative Bobby L. Rush, Chairman, Committee on Energy and Commerce, Subcommittee on Energy Representative Fred Upton, Ranking Member, Committee on Energy and Commerce, Subcommittee on Energy Representative José Serrano, Chairman, Subcommittee on Commerce, Justice, Science and Related Agencies, Committee on Appropriations, United States House of Representatives Representative Robert Aderholt, Ranking Member, Subcommittee on Commerce, Justice, Science and Related Agencies, Committee on Appropriations, United States House of Representatives Senator Lamar Alexander, Chairman, Subcommittee on Energy and Water Development Committee on Appropriations, United States Senate Senator Dianne Feinstein, Ranking Member, Subcommittee on Energy and Water Development, Committee on Appropriations, United States Senate Representative Marcy Kaptur, Chairwoman, Subcommittee on Energy and Water Development and Related Agencies, Committee on Appropriations, United States House of Representatives Representative Mike Simpson, Ranking Member, Subcommittee on Energy and Water Development, Committee on Appropriations, United States House of Representatives Dr. F. Fleming Crim, Chief Operating Officer, Office of the Director, National Science Foundation Dr. James Ulvestad, Chief Officer for Research Facilities, Office of the Director, National Science Foundation Dr. Anne Kinney, Assistant Director, Directorate for Mathematical and Physical Sciences, National Science Foundation Dr. Thomas Zurbuchen, Associate Administrator, Science Mission Directorate, National Aeronautics and Space Administration Mr. Dennis Andrucyk, Deputy Associate Administrator, Science Mission Directorate, National Aeronautics and Space Administration Dr. Paul Hertz, Director, Astrophysics Division, Science Mission Directorate, National Aeronautics and Space Administration Mr. Gabriel Adler, Office of Legislative Affairs, National Aeronautics and Space Administration Dr. J. Stephen Binkley, Deputy Director for Science Programs, Office of Science, U.S. Department of Energy Dr. James Siegrist, Director, Office of High Energy Physics, Office of Science, U.S. Department of Energy Dr. Glen Crawford, Division Director, Research and Technology Division, Office of High Energy Physics, Office of Science, U.S. Department of Energy Dr. Kathleen Turner, Program Manager, Office of High Energy Physics, Office of Science, U.S. Department of Energy Dr. Yi Pei, Program Examiner, NSF, Office of Management and Budget Dr. Grace Hu, Program Examiner, NASA, Office of Management and Budget Dr. Avital Bar-Shalom, Program Examiner, DOE, Office of Management and Budget Dr. Deborah Lockhart, Deputy Assistant Director, Directorate for Mathematical and Physical Sciences, National Science Foundation Dr. Richard Green, Division Director, Division of Astronomical Sciences, National Science Foundation Dr. Ralph Gaume, Deputy Division Director, Division of Astronomical Sciences, National Science Foundation Dr. Christopher Davis, Program Director, Division of Astronomical Sciences, National Science Foundation Ms. Amanda Greenwell, Head, Office of Legislative and Public Affairs, National Science Foundation Ms. Karen Pearce, Senior Legislative Affairs Specialist, Office of Legislative and Public Affairs, National Science Foundation Astronomy and Astrophysics Advisory Committee Members: Dr. Rachel Bean, Cornell University Dr. Andrew Connolly, University of Washington Dr. Ian Dell’Antonio, Brown University Dr. Scott Dodelson, Carnegie-Mellon University Dr. Dieter Hartmann, Clemson University Dr. Kelsey Johnson, University of Virginia Dr. Mansi Kasliwal, California Institute of Technology Dr. Brian Keating, University of California, San Diego Dr. Eliza Kempton, University of Maryland Dr. Shane Larson, Northwestern University Dr. Petrus Martens, Georgia State University Dr. John O’Meara, W.M. Keck Observatory Dr. Constance Rockosi, University of California, Santa Cruz Report of the Astronomy and Astrophysics Advisory Committee April 26, 2019 Image credit: Event Horizon Telescope Collaboration Table of Contents Report of the Astronomy and Astrophysics Advisory Committee 1 Executive Summary 3 Collected Findings and Recommendations 3 1. Introduction 10 2. Highlights of 2018 11 3. Overview of Interagency Coordination and Cooperation 16 3.1 Past and Current Coordination and Cooperation 16 3.2 Opportunities for Future Coordination and Collaboration 17 4. Implementation of Decadal Survey Recommendations 22 4.1 Priorities Addressed or Under Implementation 22 4.1.1 Space-based Projects 22 4.1.2 Ground-based Projects 29 4.1.3 Other Initiatives or Recommendations In Progress 34 4.2 Major Initiatives or Priorities Not Yet Started 36 4.3 Summary and Recommendations 38 5. GBS SubCommittee Report 39 6. Preparation for 2020 Decadal Survey 40 6.1 General preparation informed by past experience 40 6.2 Upcoming Mission Concept Development 42 6.3 Impact of the Decadal Survey Process 43 7. Budget Summary and Impact 44 Appendix A: Explanation of Acronyms 46 2 Executive Summary We list our complete set of findings and recommendations below. The findings and recommendations are developed and supported in the body of the report. Acronyms are introduced in the text and are listed in Appendix A. Collected Findings and Recommendations 1. Finding: The continuing US investment in fundamental research by DOE, NASA, and NSF has enabled important new discoveries in astronomy and astrophysics, and extended the access to this science through public data releases and outstanding
Recommended publications
  • White Dwarf Compact Binary Model for Long Gamma-Ray Bursts

    White Dwarf Compact Binary Model for Long Gamma-Ray Bursts

    MNRAS 000, 1–5 (0000) Preprint 6 October 2018 Compiled using MNRAS LATEX style file v3.0 A Black Hole - White Dwarf Compact Binary Model for Long Gamma-ray Bursts without Supernova Association Yi-Ze Dong, Wei-Min Gu ⋆, Tong Liu, and Junfeng Wang Department of Astronomy, Xiamen University, Xiamen, Fujian 361005, China 6 October 2018 ABSTRACT Gamma-ray bursts (GRBs) are luminous and violent phenomena in the universe. Tra- ditionally, long GRBs are expected to be produced by the collapse of massive stars and associated with supernovae. However, some low-redshift long GRBs have no detection of supernova association, such as GRBs 060505, 060614 and 111005A. It is hard to classify these events convincingly according to usual classifications, and the lack of the supernova implies a non-massive star origin. We propose a new path to produce long GRBs without supernova association, the unstable and extremely violent accretion in a contact binary system consisting of a stellar-mass black hole and a white dwarf, which fills an important gap in compact binary evolution. Key words: accretion, accretion discs – stars: black holes – binaries: close gamma-ray burst: general – white dwarfs 1 INTRODUCTION X-ray binaries (UCXBs) (Nelemans & Jonker 2010) and the repeating fast radio burst (FRB 121102) (Gu et al. 2016). It is generally believed that long gamma-ray bursts (GRBs) In addition, the gravitational wave emission originating originate from the collapse of massive stars and are accom- from the merger of double BHs was detected by LIGO panied with supernovae (Woosley 1993; Woosley & Bloom (Abbott et al. 2016a,b).
  • Astronomy Binder

    Astronomy Binder

    Astronomy Binder Bloomington High School South 2011 Contents 1 Astronomical Distances 2 1.1 Geometric Methods . 2 1.2 Spectroscopic Methods . 4 1.3 Standard Candle Methods . 4 1.4 Cosmological Redshift . 5 1.5 Distances to Galaxies . 5 2 Age and Size 6 2.1 Measuring Age . 6 2.2 Measuring Size . 7 3 Variable Stars 7 3.1 Pulsating Variable Stars . 7 3.1.1 Cepheid Variables . 7 3.1.2 RR Lyrae Variables . 8 3.1.3 RV Tauri Variables . 8 3.1.4 Long Period/Semiregular Variables . 8 3.2 Binary Variables . 8 3.3 Cataclysmic Variables . 11 3.3.1 Classical Nova . 11 3.3.2 Recurrent Novae . 11 3.3.3 Dwarf Novae (U Geminorum) . 11 3.3.4 X-Ray Binary . 11 3.3.5 Polar (AM Herculis) star . 12 3.3.6 Intermediate Polar (DQ Herculis) star . 12 3.3.7 Super Soft Source (SSS) . 12 3.3.8 VY Sculptoris stars . 12 3.3.9 AM Canum Venaticorum stars . 12 3.3.10 SW Sextantis stars . 13 3.3.11 Symbiotic Stars . 13 3.3.12 Pulsating White Dwarfs . 13 4 Galaxy Classification 14 4.1 Elliptical Galaxies . 14 4.2 Spirals . 15 4.3 Classification . 16 4.4 The Milky Way Galaxy (MWG . 19 4.4.1 Scale Height . 19 4.4.2 Magellanic Clouds . 20 5 Galaxy Interactions 20 6 Interstellar Medium 21 7 Active Galactic Nuclei 22 7.1 AGN Equations . 23 1 8 Spectra 25 8.1 21 cm line . 26 9 Black Holes 26 9.1 Stellar Black Holes .
  • Fundamental Parameters of 4 Massive Eclipsing Binaries in Westerlund 1

    Fundamental Parameters of 4 Massive Eclipsing Binaries in Westerlund 1

    Active OB stars: structure, evolution, mass loss and critical limits Proceedings IAU Symposium No. 272, 2010 c 2010 International Astronomical Union C. Neiner, G. Wade, G. Meynet & G. Peters DOI: 00.0000/X000000000000000X Fundamental Parameters of 4 Massive Eclipsing Binaries in Westerlund 1 E. Koumpia and A.Z. Bonanos † National Observatory of Athens, Institute of Astronomy & Astrophysics, I. Metaxa & Vas. Pavlou St., Palaia Penteli GR-15236 Athens, Greece [email protected], [email protected] Abstract. Westerlund 1 is one of the most massive young clusters known in the Local Group, with an age of 3-5 Myr. It contains an assortment of rare evolved massive stars, such as blue, yellow and red supergiants, Wolf-Rayet stars, a luminous blue variable, and a magnetar, as well as 4 massive eclipsing binary systems (Wddeb, Wd13, Wd36, WR77o, see Bonanos 2007). The eclipsing binaries present a rare opportunity to constrain evolutionary models of massive stars, the distance to the cluster and furthermore, to determine a dynamical lower limit for the mass of a magnetar progenitor. Wddeb, being a detached system, is of great interest as it allows determination of the masses of 2 of the most massive unevolved stars in the cluster. We have analyzed spectra of all 4 eclipsing binaries, taken in 2007-2008 with the 6.5 meter Magellan telescope at Las Campanas Observatory, Chile, and present fundamental parameters (masses, radii) for their component stars. Keywords. open clusters and associations: individual (Westerlund 1), stars: fundamental pa- rameters, stars: early-type, binaries: eclipsing, stars: Wolf-Rayet 1. Introduction Westerlund 1 (Wd1) is one of the most massive compact young star clusters known in the Local Group.
  • Ghost Imaging of Space Objects

    Ghost Imaging of Space Objects

    Ghost Imaging of Space Objects Dmitry V. Strekalov, Baris I. Erkmen, Igor Kulikov, and Nan Yu Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109-8099 USA NIAC Final Report September 2014 Contents I. The proposed research 1 A. Origins and motivation of this research 1 B. Proposed approach in a nutshell 3 C. Proposed approach in the context of modern astronomy 7 D. Perceived benefits and perspectives 12 II. Phase I goals and accomplishments 18 A. Introducing the theoretical model 19 B. A Gaussian absorber 28 C. Unbalanced arms configuration 32 D. Phase I summary 34 III. Phase II goals and accomplishments 37 A. Advanced theoretical analysis 38 B. On observability of a shadow gradient 47 C. Signal-to-noise ratio 49 D. From detection to imaging 59 E. Experimental demonstration 72 F. On observation of phase objects 86 IV. Dissemination and outreach 90 V. Conclusion 92 References 95 1 I. THE PROPOSED RESEARCH The NIAC Ghost Imaging of Space Objects research program has been carried out at the Jet Propulsion Laboratory, Caltech. The program consisted of Phase I (October 2011 to September 2012) and Phase II (October 2012 to September 2014). The research team consisted of Drs. Dmitry Strekalov (PI), Baris Erkmen, Igor Kulikov and Nan Yu. The team members acknowledge stimulating discussions with Drs. Leonidas Moustakas, Andrew Shapiro-Scharlotta, Victor Vilnrotter, Michael Werner and Paul Goldsmith of JPL; Maria Chekhova and Timur Iskhakov of Max Plank Institute for Physics of Light, Erlangen; Paul Nu˜nez of Coll`ege de France & Observatoire de la Cˆote d’Azur; and technical support from Victor White and Pierre Echternach of JPL.
  • Arxiv:2103.07476V1 [Astro-Ph.GA] 12 Mar 2021

    Arxiv:2103.07476V1 [Astro-Ph.GA] 12 Mar 2021

    FERMILAB-PUB-21-075-AE-LDRD Draft version September 3, 2021 Typeset using LATEX twocolumn style in AASTeX63 The DECam Local Volume Exploration Survey: Overview and First Data Release A. Drlica-Wagner ,1, 2, 3 J. L. Carlin ,4 D. L. Nidever ,5, 6 P. S. Ferguson ,7, 8 N. Kuropatkin ,1 M. Adamow´ ,9, 10 W. Cerny ,2, 3 Y. Choi ,11 J. H. Esteves,12 C. E. Mart´ınez-Vazquez´ ,13 S. Mau ,14, 15 A. E. Miller,16, 17 B. Mutlu-Pakdil ,2, 3 E. H. Neilsen ,1 K. A. G. Olsen ,6 A. B. Pace ,18 A. H. Riley ,7, 8 J. D. Sakowska ,19 D. J. Sand ,20 L. Santana-Silva ,21 E. J. Tollerud ,11 D. L. Tucker ,1 A. K. Vivas ,13 E. Zaborowski,2 A. Zenteno ,13 T. M. C. Abbott ,13 S. Allam ,1 K. Bechtol ,22, 23 C. P. M. Bell ,16 E. F. Bell ,24 P. Bilaji,2, 3 C. R. Bom ,25 J. A. Carballo-Bello ,26 D. Crnojevic´ ,27 M.-R. L. Cioni ,16 A. Diaz-Ocampo,28 T. J. L. de Boer ,29 D. Erkal ,19 R. A. Gruendl ,30, 31 D. Hernandez-Lang,32, 13, 33 A. K. Hughes,20 D. J. James ,34 L. C. Johnson ,35 T. S. Li ,36, 37, 38 Y.-Y. Mao ,39, 38 D. Mart´ınez-Delgado ,40 P. Massana,19, 41 M. McNanna ,22 R. Morgan ,22 E. O. Nadler ,14, 15 N. E. D. Noel¨ ,19 A. Palmese ,1, 2 A. H. G. Peter ,42 E. S.
  • Rhodri Evans

    Rhodri Evans

    Rhodri Evans The Cosmic Microwave Background How It Changed Our Understanding of the Universe Astronomers’ Universe More information about this series at http://www.springer.com/series/6960 Rhodri Evans The Cosmic Microwave Background How It Changed Our Understanding of the Universe 123 Rhodri Evans School of Physics & Astronomy Cardiff University Cardiff United Kingdom ISSN 1614-659X ISSN 2197-6651 (electronic) ISBN 978-3-319-09927-9 ISBN 978-3-319-09928-6 (eBook) DOI 10.1007/978-3-319-09928-6 Springer Cham Heidelberg New York Dordrecht London Library of Congress Control Number: : 2014957530 © Springer International Publishing Switzerland 2015 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law.
  • What Can Make a Contact Binary Star Explode? Evan Cook, Kenton Greene, and Prof

    What Can Make a Contact Binary Star Explode? Evan Cook, Kenton Greene, and Prof

    What Can Make a Contact Binary Star Explode? Evan Cook, Kenton Greene, and Prof. Larry Molnar, Calvin College, Grand Rapids, Michigan, Summer 2017 Supported by the Dragt Family (EC), a VanderPlas Fellowship (KG), and the National Science Foundation (LM) Introduction Merger Mechanism What To Look For Contact binary stars orbit each other so closely that they share a common Fillout Factor: atmosphere. For millions of years, these stars orbit without significant change. L2 The degree of contact in Eventually, an as yet unknown mechanism causes them to spiral together, merge, a contact binary is called and explode. the fillout factor (Fig. 3). At the upper extreme, Three years ago, we identified a contact binary system, KIC 9832227, which we the surface approaches observe to be spiraling inwards, and which we now predict will explode in the year L (on the left in Fig. 3), 2022, give or take a year. This was the first ever prediction of a nova outburst. We 2 the point at which the are using this opportunity to try to discover the mechanism behind stellar outward centrifugal mergers. To explore this question this summer, we studied our system more Fig. 3. The black line is a cross section through force balances the intensively using both optical and X-ray telescopes. We determined a more the equator of our star. The gray lines show attractive gravitational accurate shape with the PHOEBE software package (see Fig. 1). And we began a the range of possible shapes for contact stars. Fig. 6. A Hubble Space Telescope image force. Material reaching survey of the shapes The fillout factor is a parameter from 0 to 1 of a red nova, V838 Mon, that exploded L flows away from the of other contact Fig.
  • Study of Eclipsing Binaries: Light Curves & O-C Diagrams Interpretation

    Study of Eclipsing Binaries: Light Curves & O-C Diagrams Interpretation

    galaxies Review Study of Eclipsing Binaries: Light Curves & O-C Diagrams Interpretation Helen Rovithis-Livaniou Department of Astrophysics, Astronomy & Mechanics, Faculty of Physics, Panepistimiopolis, Zografos, Athens University, 15784 Athens, Greece; [email protected]; Tel.: +30-21-0984-7232 Received: 10 October 2020; Accepted: 6 November 2020; Published: 13 November 2020 Abstract: The continuous improvement in observational methods of eclipsing binaries, EBs, yield more accurate data, while the development of their light curves, that is magnitude versus time, analysis yield more precise results. Even so, and in spite the large number of EBs and the huge amount of observational data obtained mainly by space missions, the ways of getting the appropriate information for their physical parameters etc. is either from their light curves and/or from their period variations via the study of their (O-C) diagrams. The latter express the differences between the observed, O, and the calculated, C, times of minimum light. Thus, old and new light curves analysis methods of EBs to obtain their principal parameters will be considered, with examples mainly from our own observational material, and their subsequent light curves analysis using either old or new methods. Similarly, the orbital period changes of EBs via their (O-C) diagrams are referred to with emphasis on the use of continuous methods for their treatment in absence of sudden or abrupt events. Finally, a general discussion is given concerning these two topics as well as to a few related subjects. Keywords: eclipsing binaries; light curves analysis/synthesis; minima times and (O-C) diagrams 1. Introduction A lot of time has passed since the primitive observations of EBs made with naked eye till today’s space surveys.
  • The Massive Wolf-Rayet Binary LSS 1964 (=WR 29) II

    The Massive Wolf-Rayet Binary LSS 1964 (=WR 29) II

    A&A 506, 1269–1275 (2009) Astronomy DOI: 10.1051/0004-6361/200810112 & c ESO 2009 Astrophysics The massive Wolf-Rayet binary LSS 1964 (=WR 29) II. The V light curve R. C. Gamen1,2,, E. Fernández-Lajús1,2,†,V.S.Niemela‡, and R. H. Barbá3,4,§ 1 Instituto de Astrofísica de La Plata, CONICET, Paseo del bosque s/n, B1900FWA, La Plata, Argentina 2 Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del bosque s/n, B1900FWA, La Plata, Argentina e-mail: [email protected] 3 Instituto de Ciencias Astronómicas de la Tierra y del Espacio, CONICET, Avda. España 1512 Sur, J5402DSP, San Juan, Argentina 4 Departamento de Física, Universidad de La Serena, Benavente 980, La Serena, Chile Received 2 May 2008 / Accepted 1 August 2009 ABSTRACT Context. WR 29 is a known WN7h+O double-lined binary system with a rather short period (3.164 days). Aims. We search for light variations to determine the inclination of the system and thus the absolute masses of both components. Methods. We observed photometrically the field of WR 29 between December, 2002, and February, 2006. Results. We find that the V light of WR 29 varies in phase with the spectroscopic period of 3.16412 days, presenting two minima corresponding to the conjunctions of the binary components. Numerical models fitted to the light curve indicate an orbital inclination ◦ of about 44 , and masses of 53 M and 42 M for the O- and WN-type components, respectively. Key words. stars: binaries: close – stars: binaries: eclipsing – stars: binaries: spectroscopic – stars: Wolf-Rayet 1.
  • April 14 2018 7:00Pm at the April 2018 Herrett Center for Arts & Science College of Southern Idaho

    April 14 2018 7:00Pm at the April 2018 Herrett Center for Arts & Science College of Southern Idaho

    Snake River Skies The Newsletter of the Magic Valley Astronomical Society www.mvastro.org Membership Meeting President’s Message Tim Frazier Saturday, April 14th 2018 April 2018 7:00pm at the Herrett Center for Arts & Science College of Southern Idaho. It really is beginning to feel like spring. The weather is more moderate and there will be, hopefully, clearer skies. (I write this with some trepidation as I don’t want to jinx Public Star Party Follows at the it in a manner similar to buying new equipment will ensure at least two weeks of Centennial Observatory cloudy weather.) Along with the season comes some great spring viewing. Leo is high overhead in the early evening with its compliment of galaxies as is Coma Club Officers Berenices and Virgo with that dense cluster of extragalactic objects. Tim Frazier, President One of my first forays into the Coma-Virgo cluster was in the early 1960’s with my [email protected] new 4 ¼ inch f/10 reflector and my first star chart, the epoch 1960 version of Norton’s Star Atlas. I figured from the maps I couldn’t miss seeing something since Robert Mayer, Vice President there were so many so closely packed. That became the real problem as they all [email protected] appeared as fuzzy spots and the maps were not detailed enough to distinguish one galaxy from another. I still have that atlas as it was a precious Christmas gift from Gary Leavitt, Secretary my grandparents but now I use better maps, larger scopes and GOTO to make sure [email protected] it is M84 or M86.
  • FY13 High-Level Deliverables

    FY13 High-Level Deliverables

    National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................
  • Uranometría Argentina Bicentenario

    Uranometría Argentina Bicentenario

    URANOMETRÍA ARGENTINA BICENTENARIO Reedición electrónica ampliada, ilustrada y actualizada de la URANOMETRÍA ARGENTINA Brillantez y posición de las estrellas fijas, hasta la séptima magnitud, comprendidas dentro de cien grados del polo austral. Resultados del Observatorio Nacional Argentino, Volumen I. Publicados por el observatorio 1879. Con Atlas (1877) 1 Observatorio Nacional Argentino Dirección: Benjamin Apthorp Gould Observadores: John M. Thome - William M. Davis - Miles Rock - Clarence L. Hathaway Walter G. Davis - Frank Hagar Bigelow Mapas del Atlas dibujados por: Albert K. Mansfield Tomado de Paolantonio S. y Minniti E. (2001) Uranometría Argentina 2001, Historia del Observatorio Nacional Argentino. SECyT-OA Universidad Nacional de Córdoba, Córdoba. Santiago Paolantonio 2010 La importancia de la Uranometría1 Argentina descansa en las sólidas bases científicas sobre la cual fue realizada. Esta obra, cuidada en los más pequeños detalles, se debe sin dudas a la genialidad del entonces director del Observatorio Nacional Argentino, Dr. Benjamin A. Gould. Pero nada de esto se habría hecho realidad sin la gran habilidad, el esfuerzo y la dedicación brindada por los cuatro primeros ayudantes del Observatorio, John M. Thome, William M. Davis, Miles Rock y Clarence L. Hathaway, así como de Walter G. Davis y Frank Hagar Bigelow que se integraron más tarde a la institución. Entre éstos, J. M. Thome, merece un lugar destacado por la esmerada revisión, control de las posiciones y determinaciones de brillos, tal como el mismo Director lo reconoce en el prólogo de la publicación. Por otro lado, Albert K. Mansfield tuvo un papel clave en la difícil confección de los mapas del Atlas. La Uranometría Argentina sobresale entre los trabajos realizados hasta ese momento, por múltiples razones: Por la profundidad en magnitud, ya que llega por vez primera en este tipo de empresa a la séptima.