RASC Bulletin October 1994
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I N S I D E T H I S I S S
Publications from February/février 1998 Volume/volume 92 Number/numero 1 [669] The Royal Astronomical Society of Canada The Beginner’s Observing Guide This guide is for anyone with little or no experience in observing the night sky. Large, easy to read star maps are provided to acquaint the reader with the constellations and bright stars. Basic information on observing the moon, planets and eclipses through the year 2000 is provided. There The Journal of the Royal Astronomical Society of Canada Le Journal de la Société royale d’astronomie du Canada is also a special section to help Scouts, Cubs, Guides and Brownies achieve their respective astronomy badges. Written by Leo Enright (160 pages of information in a soft-cover book with a spiral binding which allows the book to lie flat). Price: $12 (includes taxes, postage and handling) Looking Up: A History of the Royal Astronomical Society of Canada Published to commemorate the 125th anniversary of the first meeting of the Toronto Astronomical Club, “Looking Up — A History of the RASC” is an excellent overall history of Canada’s national astronomy organization. The book was written by R. Peter Broughton, a Past President and expert on the history of astronomy in Canada. Histories on each of the centres across the country are included as well as dozens of biographical sketches of the many people who have volunteered their time and skills to the Society. (hard cover with cloth binding, 300 pages with 150 b&w illustrations) Price: $43 (includes taxes, postage and handling) Observers Calendar — 1998 This calendar was created by members of the RASC. -
Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects
Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Porto Alegre 2017 Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Dissertação elaborada sob orientação do Prof. Dr. Eduardo Luis Damiani Bica, co- orientação do Prof. Dr. Charles José Bon- ato e apresentada ao Instituto de Física da Universidade Federal do Rio Grande do Sul em preenchimento do requisito par- cial para obtenção do título de Mestre em Física. Porto Alegre 2017 Acknowledgements To my parents, who supported me and made this possible, in a time and place where being in a university was just a distant dream. To my dearest friends Elisabeth, Robert, Augusto, and Natália - who so many times helped me go from "I give up" to "I’ll try once more". To my cats Kira, Fen, and Demi - who lazily join me in bed at the end of the day, and make everything worthwhile. "But, first of all, it will be necessary to explain what is our idea of a cluster of stars, and by what means we have obtained it. For an instance, I shall take the phenomenon which presents itself in many clusters: It is that of a number of lucid spots, of equal lustre, scattered over a circular space, in such a manner as to appear gradually more compressed towards the middle; and which compression, in the clusters to which I allude, is generally carried so far, as, by imperceptible degrees, to end in a luminous center, of a resolvable blaze of light." William Herschel, 1789 Abstract We provide a sample of 170 Galactic Globular Clusters (GCs) and analyse its spatial distribution properties. -
Authentic Data in the Classroom with the Sloan Digital Sky Survey
Proc. of the GHOU 2007 in Tokyo Authentic Data in the Classroom with the Sloan Digital Sky Survey M. Jordan Raddick* 1 Student engagement with the process of science is a proven part of highquality science education, but authentic science activities can be difficult in astronomy because of the difficulty students have in taking data. This paper describes how the Sloan Digital Sky Survey (SDSS) contributes to solving this problem by making its entire dataset available to students and the public, free of charge. The survey's SkyServer website (http://skyserver.sdss.org) includes simple tools to browse and search the data, as well as projects that use the data to teach science. The dataset is also a great source of independent research projects for students. 1. Introduction for each star or galaxy, including magnitudes and object types. Images are available as FITS files. Movements in science education reform in the The survey also measures followup spectra for United States and around the world frequently cite stars, galaxies and quasars. These spectra run from engagement with the process of science as a key 3800 to 9200 Ångstroms, and have a resolution of component of effective science learning, and 1.8 Ångstroms per pixel. They are available as GIF scientific inquiry as an important part of images or FITS files, and detailed line widths and understanding science [1,2]. strengths are available for each spectral line. Laboratory activities in other science subjects frequently make use of student inquiry labs, in which 3. SkyServer students make their own observations, interpret the results, and draw conclusions. -
Direct N-Body Simulations of Globular Clusters--III. Palomar\, 4 on An
MNRAS 000, 1–11 (2013) Preprint 14 September 2018 Compiled using MNRAS LATEX style file v3.0 Direct N-body simulations of globular clusters – III. Palomar4 on an eccentric orbit Akram Hasani Zonoozi1⋆, Hosein Haghi1, Pavel Kroupa2,3, Andreas H.W. K¨upper4†, Holger Baumgardt5 1Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), PO Box 11365-9161, Zanjan, Iran 2Helmholtz-Institut f¨ur Strahlen-und Kernphysik (HISKP), Universit¨at Bonn, Nussallee 14-16, D-53115 Bonn, Germany 3Charles University in Prague, Faculty of Mathematics and Physics, Astronomical Institute, V Holeˇsoviˇck´ach 2, CZ-180 00 Praha 8, Czech Republic 4Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027, USA 5School of Mathematics and Physics, University of Queensland, Brisbane, QLD 4072, Australia Accepted .... Received ABSTRACT Palomar 4 is a low-density globular cluster with a current mass ≈ 30000 M⊙in the outer halo of the Milky Way with a two-body relaxation time of the order of a Hubble time. Yet, it is strongly mass segregated and contains a stellar mass function depleted of low-mass stars. Pal 4 was either born this way or it is a result of extraordi- nary dynamical evolution. Since two-body relaxation cannot explain these signatures alone, enhanced mass loss through tidal shocking may have had a strong influence on Pal 4. Here, we compute a grid of direct N-body simulations to model Pal4 on various eccentric orbits within the Milky Way potential to find likely initial conditions that reproduce its observed mass, half-light radius, stellar MF-slope and line-of-sight ve- locity dispersion. -
Guide Du Ciel Profond
Guide du ciel profond Olivier PETIT 8 mai 2004 2 Introduction hjjdfhgf ghjfghfd fg hdfjgdf gfdhfdk dfkgfd fghfkg fdkg fhdkg fkg kfghfhk Table des mati`eres I Objets par constellation 21 1 Androm`ede (And) Andromeda 23 1.1 Messier 31 (La grande Galaxie d'Androm`ede) . 25 1.2 Messier 32 . 27 1.3 Messier 110 . 29 1.4 NGC 404 . 31 1.5 NGC 752 . 33 1.6 NGC 891 . 35 1.7 NGC 7640 . 37 1.8 NGC 7662 (La boule de neige bleue) . 39 2 La Machine pneumatique (Ant) Antlia 41 2.1 NGC 2997 . 43 3 le Verseau (Aqr) Aquarius 45 3.1 Messier 2 . 47 3.2 Messier 72 . 49 3.3 Messier 73 . 51 3.4 NGC 7009 (La n¶ebuleuse Saturne) . 53 3.5 NGC 7293 (La n¶ebuleuse de l'h¶elice) . 56 3.6 NGC 7492 . 58 3.7 NGC 7606 . 60 3.8 Cederblad 211 (N¶ebuleuse de R Aquarii) . 62 4 l'Aigle (Aql) Aquila 63 4.1 NGC 6709 . 65 4.2 NGC 6741 . 67 4.3 NGC 6751 (La n¶ebuleuse de l’œil flou) . 69 4.4 NGC 6760 . 71 4.5 NGC 6781 (Le nid de l'Aigle ) . 73 TABLE DES MATIERES` 5 4.6 NGC 6790 . 75 4.7 NGC 6804 . 77 4.8 Barnard 142-143 (La tani`ere noire) . 79 5 le B¶elier (Ari) Aries 81 5.1 NGC 772 . 83 6 le Cocher (Aur) Auriga 85 6.1 Messier 36 . 87 6.2 Messier 37 . 89 6.3 Messier 38 . -
Science in the Urantia Papers
Science ¾ Scientific Validation of the UB z By Denver Pearson z By Phil Calabrese ¾ Seraphic Velocities ¾ Astronomy The Scientific Integrity of the Urantia Book by Denver Pearson As scientifically minded readers first peruse the Urantia Book, it soon occurs to them that many of its statements on the natural sciences conflict with currently held data and theories. In the minds of many this gives rise to doubts about the truthfulness of those statements. Wisdom would lead us to realize that nothing short of perfection is perfect, and anything touched by human hands has fingerprints. This should be our guiding thoughts as we contemplate the accuracy of the scientific content of the Urantia Papers. Several years ago, at the first scientific symposium, it was implied by one of the speakers that the revelation contains errors. This implication is alarming. More recently, at the second symposium held in Oklahoma, an interesting publication named "The Science Content of The Urantia Book" was made available (this document is obtainable from the Brotherhood of Man Library). In this publication is an article entitled "Time Bombs" in which the author suggests that the revelators planted certain inaccurate scientific statements in the book in order to prevent it from becoming a fetish. He states "...the revelators incorporated safeguards in the papers that would form The Urantia Book to diminish the tendency to regard it as an object of worship. What safeguards did they use? Suppose they decided to make sure that mortals reading it understood that some cosmological statements in the book would be found to be inaccurate". -
Hubble Sees a Unique Cluster: One of the 'Hidden 15' 22 April 2013
Hubble sees a unique cluster: One of the 'hidden 15' 22 April 2013 almost always see them in the same region of the sky. Palomar 2 is an exception to this, as it is around five times further away from the center of the Milky Way than other clusters. It also lies in the opposite direction—further out than Earth—and so it is classed as an "outer halo" globular. It is also unusual due to its apparent dimness. The cluster is veiled by a mask of dust, dampening the apparent brightness of the stars within it and making it appear as a very faint burst of stars. The stunning NASA/ESA Hubble Space Telescope image shows Palomar 2 in a way that could not be captured from smaller or ground-based telescopes—some amateur astronomers with large telescopes attempt to observe all of the obscure and well-hidden Palomar 15 as a challenge, to see how many they can pick out from the starry sky. Credit: ESA/NASA, Hubble Provided by NASA (Phys.org) —Palomar 2 is part of a group of 15 globulars known as the Palomar clusters. These clusters, as the name suggests, were discovered in survey plates from the first Palomar Observatory Sky Survey in the 1950s, a project that involved some of the most well-known astronomers of the day, including Edwin Hubble. They were discovered quite late because they are so faint—each is either extremely remote, very heavily hidden behind blankets of dust, or has a very small number of remaining stars. This particular cluster is unique in more than one way. -
Young Globular Clusters and Dwarf Spheroidals
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server Young Globular Clusters and Dwarf Spheroidals Sidney van den Bergh Dominion Astrophysical Observatory Herzberg Institute of Astrophysics National Research Council of Canada 5071 West Saanich Road Victoria, British Columbia, V8X 4M6 Canada ABSTRACT Most of the globular clusters in the main body of the Galactic halo were formed almost simultaneously. However, globular cluster formation in dwarf spheroidal galaxies appears to have extended over a significant fraction of a Hubble time. This suggests that the factors which suppressed late-time formation of globulars in the main body of the Galactic halo were not operative in dwarf spheroidal galaxies. Possibly the presence of significant numbers of “young” globulars at RGC > 15 kpc can be accounted for by the assumption that many of these objects were formed in Sagittarius-like (but not Fornax-like) dwarf spheroidal galaxies, that were subsequently destroyed by Galactic tidal forces. It would be of interest to search for low-luminosity remnants of parental dwarf spheroidals around the “young” globulars Eridanus, Palomar 1, 3, 14, and Terzan 7. Furthermore multi-color photometry could be used to search for the remnants of the super-associations, within which outer halo globular clusters originally formed. Such envelopes are expected to have been tidally stripped from globulars in the inner halo. Subject headings: Globular clusters - galaxies: dwarf The galaxy is, in fact, nothing but a congeries of innumerable stars grouped together in clusters. Galileo (1610) –2– 1. Introduction The vast majority of Galactic globular clusters appear to have formed at about the same time (e.g. -
Arxiv:1307.6035V1 [Astro-Ph.GA] 23 Jul 2013 Uaeydtriigterpoete,Ms Ftegalac- the of Most Properties, Their Determining Curately Et Ferraro the 1997; on Heggie 2012)
Draft version July 24, 2013 A Preprint typeset using LTEX style emulateapj v. 12/16/11 STAR COUNT DENSITY PROFILES AND STRUCTURAL PARAMETERS OF 26 GALACTIC GLOBULAR CLUSTERS P. Miocchi1, B. Lanzoni1, F.R. Ferraro1, E. Dalessandro1, E. Vesperini2, M. Pasquato3 , G. Beccari4, C. Pallanca1, and N. Sanna1 1Dipartimento di Fisica e Astronomia, Universit`adi Bologna, Viale Berti Pichat 6/2, 40127 Bologna, Italy 2Department of Astronomy, Indiana University, Bloomington, Indiana 47405, USA 3Department of Astronomy & Center for Galaxy Evolution Research, Yonsei University, and Yonsei University Observatory, Seoul 120-749, Republic of Korea 4European Organization for Astronomical Research in the Southern Hemisphere, K. Schwarzschild-Str. 2, 85748 Garching, Germany Draft version July 24, 2013 ABSTRACT We used a proper combination of high-resolution HST observations and wide-field ground based data to derive the radial star density profile of 26 Galactic globular clusters from resolved star counts (which can be all freely downloaded on-line). With respect to surface brightness (SB) profiles (which can be biased by the presence of sparse, bright stars), star counts are considered to be the most robust and reliable tool to derive cluster structural parameters. For each system a detailed comparison with both King and Wilson models has been performed and the most relevant best-fit parameters have been obtained. This is the largest homogeneous catalog collected so far of star count profiles and structural parameters derived therefrom. The analysis of the data -
Taking the Measure of the Universe: Precision Astrometry with SIM
Accepted for publication in PASP, January 2008 issue A Preprint typeset using LTEX style emulateapj v. 08/22/09 TAKING THE MEASURE OF THE UNIVERSE: PRECISION ASTROMETRY WITH SIM PLANETQUEST Stephen C. Unwin1, Michael Shao2, Angelle M. Tanner2, Ronald J. Allen3, Charles A. Beichman4, David Boboltz5, Joseph H. Catanzarite2, Brian C. Chaboyer6, David R. Ciardi4, Stephen J. Edberg2, Alan L. Fey5, Debra A. Fischer7, Christopher R. Gelino8, Andrew P. Gould9, Carl Grillmair8, Todd J. Henry10, Kathryn V. Johnston11,12, Kenneth J. Johnston5, Dayton L. Jones2, Shrinivas R. Kulkarni4, Nicholas M. Law4, Steven R. Majewski13, Valeri V. Makarov2, Geoffrey W. Marcy14, David L. Meier2, Rob P. Olling15, Xiaopei Pan2, Richard J. Patterson13, Jo Eliza Pitesky2, Andreas Quirrenbach16, Stuart B. Shaklan2, Edward J. Shaya15, Louis E. Strigari17, John A. Tomsick18,19, Ann E. Wehrle20, and Guy Worthey21 Accepted for publication in PASP, January 2008 issue ABSTRACT Precision astrometry at microarcsecond accuracy has application to a wide range of astrophysical problems. This paper is a study of the science questions that can be addressed using an instrument with flexible scheduling that delivers parallaxes at about 4 microarcsec (µas) on targets as faint as V = 20, and differential accuracy of 0.6 µas on bright targets. The science topics are drawn primarily from the Team Key Projects, selected in 2000, for the Space Interferometry Mission PlanetQuest (SIM PlanetQuest). We use the capabilities of this mission to illustrate the importance of the next level of astrometric precision in modern astrophysics. SIM PlanetQuest is currently in the detailed design phase, having completed in 2005 all of the enabling technologies needed for the flight instrument. -
Multiwavelength, Machine Learning, and Parallax Studies of X-Ray Binaries in Three Local Group Galaxies
Western University Scholarship@Western Electronic Thesis and Dissertation Repository 12-7-2018 1:30 PM Multiwavelength, Machine Learning, and Parallax Studies of X-ray Binaries in Three Local Group Galaxies Robin Arnason The University of Western Ontario Supervisor Barmby, Pauline The University of Western Ontario Graduate Program in Astronomy A thesis submitted in partial fulfillment of the equirr ements for the degree in Doctor of Philosophy © Robin Arnason 2018 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the External Galaxies Commons Recommended Citation Arnason, Robin, "Multiwavelength, Machine Learning, and Parallax Studies of X-ray Binaries in Three Local Group Galaxies" (2018). Electronic Thesis and Dissertation Repository. 5931. https://ir.lib.uwo.ca/etd/5931 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Abstract X-ray binary stars are rare systems consisting of a black hole or neutron star and a main- sequence companion star. They are useful probes of galaxy properties and interesting labora- tories for extreme physical conditions. In this thesis, I investigated the X-ray binary population of three galaxies in the Local Group. The Sculptor Dwarf Spheroidal Galaxy offers the chance to study a primordial low-mass X-ray binary (LMXB) population in an isolated, low-metallicity environment. Combining X- ray, optical, and infrared observations, I have studied nine previously identified and discovered four additional LMXB candidates in this galaxy. -
Small Wonders: Ophiuchus
Page 1 of 13 Small Wonders: Ophiuchus Small Wonders: Ophiuchus A monthly sky guide for the beginning to intermediate amateur astronomer Tom Trusock - 06/09 Barnard 72 (The Snake Nebula) - One of the many dark nebulae in Ophiuchus: Contributed by Hunter Wilson Tom Trusock June 2009 Page 2 of 13 Small Wonders: Ophiuchus This massive constellation culminates around midnight on June 12th and for me, has always been the harbinger of Summer. As with many constellations, it's mythology is somewhat mixed, but the most prevalent mythos is it's association with Aesculapius, surgeon aboard Jason's Argo. I've been an amateur astronomer for decades now, but I'm still awed by the sheer size of this constellation. Bordered on the north by Hercules and the south by Scorpius and Sagittarius, it reaches from +14 to just beneath -30 declination, and covers nearly three hours in right ascension and splits Serpens neatly in two. Widefield Finder Chart - Looking South, early June around 12pm. It's brightest star is 2nd magnitude Rasalhague located at the top of the constellations distinctive bell shape. The most interesting star within it's borders is probably the mag 9.5 red dwarf named Barnard's Star. Discovered in 1916 by E. E. Barnard, it's six light years away (making it the second closest star) and has a proper motion in our sky of one degree every 350 years. Barnard's star is approaching us rapidly – around 87 miles per second – and will reach closest approach of 3.8 light years around 8000 years from now.