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Occuttau'm@Newsteuer
Occuttau'm@Newsteuer Volume IV, Number 3 january, 1987 ISSN 0737-6766 Occultation Newsletter is published by the International Occultation Timing Association. Editor and compos- itor: H. F. DaBo11; 6N106 White Oak Lane; St. Charles, IL 60174; U.S.A. Please send editorial matters, new and renewal memberships and subscriptions, back issue requests, address changes, graze prediction requests, reimbursement requests, special requests, and other IOTA business, but not observation reports, to the above. FROM THE PUBLISHER IOTA NEWS This is the first issue of 1987. Some reductions in David Id. Dunham prices of back issues are shown below. The main purpose of this issue is to distribute pre- dictions and charts for planetary and asteroidal oc- When renewing, please give your name and address exactly as they ap- pear on your mailing label, so that we can locate your file; if the cultations that occur during at least the first part label should be revised, tell us how it should be changed. of 1987. As explained in the article about these If you wish, you may use your VISA or NsterCard for payments to IOTA; events starting on p. 41, the production of this ma- include the account number, the expiration date, and your signature. terial was delayed by successful efforts to improve Card users must pay the full prices. If paying by cash, check, or the prediction system and various year-end pres- money order, please pay only the discount prices. Full Discount sures, including the distribution o"' lunar grazing price price occultation predictions. Unfortunately, this issue IOTA membership dues (incl. -
Molecular Outflows Identified in the FCRAO CO Survey of the Taurus
Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 10 November 2018 (MN LATEX style file v2.2) Molecular Outflows Identified in the FCRAO CO Survey of the Taurus Molecular Cloud Gopal Narayanan1, Ronald Snell1, and Ashley Bemis1;2 1 Dept. of Astronomy, Univ. of Massachusetts, Amherst MA 01003 2 Department of Physics and Astronomy, Bonn University, Wegelerstrasse 8, 53115 Bonn, Germany Received 2012 June 14; in original form 2012 April 23; accepted 2012 June 22 ABSTRACT Jets and outflows are an integral part of the star formation process. While there are many detailed studies of molecular outflows towards individual star-forming sites, few studies have surveyed an entire star-forming molecular cloud for this phenomenon. The 100 square degree FCRAO CO survey of the Taurus molecular cloud provides an excellent opportunity to under- take an unbiased survey of a large, nearby, molecular cloud complex for molecular outflow activity. Our study provides information on the extent, energetics and frequency of outflows in this region, which are then used to assess the impact of outflows on the parent molecular cloud. The search identified 20 outflows in the Taurus region, 8 of which were previously unknown. Both 12CO and 13CO data cubes from the Taurus molecular map were used, and dynamical properties of the outflows are derived. Even for previously known outflows, our large-scale maps indicate that many of the outflows are much larger than previously suspected, with eight of the flows (40%) being more than a parsec long. The mass, momentum and kinetic energy from the 20 outflows are compared to the repository of turbulent energy in Taurus. -
Organic Molecules and Water in the Inner Disks of T Tauri Stars
Organic Molecules and Water in the Inner Disks of T Tauri Stars John S. Carr Naval Research Laboratory, Code 7211, Washington, DC 20375, USA [email protected] Joan R. Najita National Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ 85716, USA [email protected] ABSTRACT We report high signal-to-noise Spitzer IRS spectra of a sample of eleven classical T Tauri stars. Molecular emission from rotational transitions of H2O and OH and ro-vibrational bands of simple organic molecules (CO2, HCN, C2H2) is common among the sources in the sample. The emission shows a range in both flux and line-to-continuum ratio for each molecule and in the flux ratios of different molecular species. The gas temperatures (200–800 K) and emitting areas we derive are consistent with the emission originating in a warm disk atmosphere in the inner planet formation region at radii < 2 AU. The H2O emission appears to form under a limited range of excitation conditions, as demonstrated by the similarity in relative strengths of H2O features from star to star and the narrow range in derived temperature and column density. Emission from highly excited rotational levels of OH is present in all stars; the OH emission flux increases with the stellar accretion rate, and the OH/H2O flux ratio shows a relatively small scatter. We interpret these results as evidence for OH production via FUV photo-dissociation of H2O in the disk surface layers. No obvious explanation is found for the observed range in the relative emission strengths of different organic molecules or in their strength with respect to water. -
Sky-High 2009
Sky-High 2009 Total Solar Eclipse, 29th March 2006 The 17th annual guide to astronomical phenomena visible from Ireland during the year ahead (naked-eye, binocular and beyond) By John O’Neill and Liam Smyth Published by the Irish Astronomical Society € 5 P.O. Box 2547, Dublin 14, Ireland. e-mail: [email protected] www.irishastrosoc.org Page 1 Foreword Contents 3 Your Night Sky Primer We send greetings to all fellow astronomers and welcome them to this, the seventeenth edition of 5 Sky Diary 2009 Sky-High. 8 Phases of Moon; Sunrise and Sunset in 2009 We thank the following contributors for their 9 The Planets in 2009 articles: Patricia Carroll, John Flannery and James O’Connor. The remaining material was written by 12 Eclipses in 2009 the editors John O’Neill and Liam Smyth. The Gal- 14 Comets in 2009 lery has images and drawings by Society members. The times of sunrise etc. are from SUNRISE by J. 16 Meteors Showers in 2009 O’Neill. 17 Asteroids in 2009 We are always glad to hear what you liked, or 18 Variable Stars in 2009 what you would like to have included in Sky-High. If we have slipped up on any matter of fact, let us 19 A Brief Trip Southwards know. We can put a correction in future issues. And if you have any problem with understanding 20 Deciphering Star Names the contents or would like more information on 22 Epsilon Aurigae – a long period variable any topic, feel free to contact us at the Society e- mail address [email protected]. -
Macrocosmo Nº24
A PRIMEIRA REVISTA ELETRÔNICA BRASILEIRA EXCLUSIVA DE ASTRONOMIA macroCOSMO .com ISSN 1808-0731 Ano II - Edição n° 24 - Novembro de 2005 Eclipse Anular 3 de outubro de 2005 O O ^^Q uando a W Lua S o l oculta o w l Cratera de Colônia 25 anos da Aspectos Gerais The Planetary Society revista macroCOSMO .com Ano II - Edição n° 24 - Novembro de 2005 Editorial Redação [email protected] Assim como tantos outros fenômenos naturais, para as primeiras civilizações, os eclipses já foram atribuídos à sinais de múltiplas Diretor Editor Chefe divindades. Eclipses Solares e Lunares, eventos estes repentinos que Hemerson Brandão quebravam a imutabilidade do céu, eram interpretados como [email protected] manifestações de ira dos deuses, predizendo morte de chefes de estado, grandes catástrofes, guerras, e várias pragas. Diagramadores Mesmo nos dias de hoje, com toda a tecnologia e conhecimento Hemerson Brandão adquirido é comum pessoas ficarem receosas com o desaparecimento [email protected] repentino temporário do Sol ou da Lua. Exemplo disso são alguns cristãos Rodolfo Saccani fanáticos, que afirmam que os eclipses são indícios do “fim do mundo”. [email protected] Durante a história, enquanto alguns povos nômades cultivavam um Sharon Camargo temor mítico por esses fenômenos, povos sedentários se empenhavam [email protected] em entender sobre a periodicidade desses fenômenos raros, tentando encontrar padrões que permitissem a previsão dos eclipses. Para isso, Revisão muitos povos erigiram grandes templos e observatórios para estudo e Tasso Napoleão previsão de eclipses além de outros fenômenos celestes. Há quem afirme [email protected] que as pedras megalíticas de Stonehenge, nas ilhas britânicas, estão Walkiria Schulz dispostas numa posição que permitia ao povo que o construiu, prever [email protected] eclipses, há mais de 3700 anos. -
La Constelacion De Tauro
LA CONSTELACION DE TAURO Es una de las constelaciones más interesantes desde el punto de vista observacional entre las que podemos ver desde el hemisferio norte. En la zona de la bóveda celeste donde identificamos la constelación de Tauro encontramos estrellas dobles y dos bellísimos cúmulos abiertos, asi como la famosa Nebulosa del Cangrejo, objeto Messier M1. 1. Las constelaciones: una aparente imágen estelar: Desde nuestra perspectiva visual como habitantes de un pequeño planeta orbitando alrededor de una estrella en una cierta galaxia espiral, observamos, en todas las direcciones de la bóveda celeste, agrupaciones aparentes de estrellas que llamamos constelaciones. Decimos que son agrupaciones aparentes porque, realmente, no tienen que estar - de hecho no lo están en general - agrupadas físicamente. Es esta la misma situación que se nos plantea en nuestra vida cotidiana cuando observamos a lo lejos dos objetos que aparentan estar juntos, y, ante la duda de si lo están o no, nosotros nos movemos lateralmente a una distancia suficiente para observarlos desde una perspectiva lateral. Es en ese momento cuando, vistos desde otro ángulo, comprobamos si están entre sí próximos o no. Este movimiento lateral es muy sencillo de realizar en nuestros avatares de la vida cotidiana, pero es evidente que, a escala astronómica, es imposible con la tecnología existente en nuestra civilización. Es imposible para nosotros salir de la Vía Láctea, nuestra galaxia espiral, para poder observar “lateralmente” una cierta estrella doble, por ejemplo, de la que sospechamos que no es una doble física, interactuando gravitacionalmente, sino que es una doble de perspectiva. Existen métodos radiométricos, espectrométricos, etc.., que nos permiten calcular la distancia de la estrellas que observamos a simple vista, y sabemos que en general, la distancia a nosotros de astros de una misma constelación varía grandemente. -
CURRICULUM VITAE Name: Matthew A. Wood Address
CURRICULUM VITAE Name: Matthew A. Wood Address: Department of Physics and Astronomy Texas A&M University{Commerce Tel: 903-886-5488 Email: [email protected] Education: Ph.D., Astronomy: The University of Texas at Austin, May 1990 M.A., Astronomy: The University of Texas at Austin, Dec. 1985 B.Sci., Physics: Iowa State University, May 1983 Work Experience: 8/12 { Present Deptartment Head & Professor Department of Physics and Astronomy Texas A&M University{Commerce 8/04 { 7/12 Professor Department of Physics & Space Sciences Florida Institute of Technology 8/96 { 7/04 Associate Professor Florida Institute of Technology 6/91 { 7/96 Assistant Professor Florida Institute of Technology 6/90 { 5/91 NSF{NATO Postdoctoral Fellow D´epartement de Physique Universit´ede Montr´eal Societies: American Astronomical Society International Astronomical Union Royal Astronomical Society Sigma Pi Sigma Florida Academy of Sciences Visiting Scientist: International Ultraviolet Explorer Satellite (NASA/Goddard) Kitt Peak National Observatory Mauna Kea Observatory Keck Observatory Hubble Space Telescope McDonald Observatory Proposal Reviewer: NSF / NASA / NOAO / NOVA (Dutch NSF) Referee: The Astrophysical Journal (Main Journal and Letters) Monthly Notices of the Royal Astronomical Society Astronomy and Astrophysics SCIENCE Publications of the Astronomical Society of the Pacific Astrophysics and Space Science Matthew A. Wood Curriculum Vitae Page 2 Major Grants: PI on grants totaling USD $1.9 million. Selected recent: NASA Kepler Mission (PI) \Cataclysmic Variables -
Astronomy with an Opera-Glass
SSSTRONOMY : : Opera-Glass V ASTRONOMY WITH AN OPEEA-GLASS A POPULAE INTRODUCTION TO THE STUDY OF THE STARRY HEAVENS WITH THE SIMPLEST OF OPTICAL INSTRUMENTS WITH MAPS AND DIRECTIONS TO FACILITATE THE RECOGNITION OF THE CONSTELLATIONS AND THE PRINCIPAL STARS VISIBLE TO THE NAKED EYE BY GARRETT P. SERVISS n " Known are their laws ; in harmony unroll The nineteen-orbed cycles of the Moon. And all the signs through which Night whirls her car From belted Orion back to Orion and his dauntless Hound, And all Poseidon's, all high Zeus' stars Bear on their beams true messages to man." Poste's Arattls. EIGHTH EDITION, WITH APPENDIX NEW YOEK D. APPLETON AND COMPANY 72 FIFTH AVENUE LONDON: 33 BEDFORD STREET 1896 Or • \%**- COPYRIGHT, 1888, By D. APPLETON AJSD COMPANY. .. ^ . TO THE READEK. In the pages that follow, the author has endeavored to encourage the study of the heavenly bodies by pointing out some of the interesting and marvelous phenomena of the uni- verse that are visible with little or no assistance from optical instruments, and indicating means of becoming acquainted with the constellations and the planets. Knowing that an opera-glass is capable of revealing some of the most beautiful sights in the starry dome, and believing that many persons would be glad to learn the fact, he set to work with such an instrument and surveyed all the constellations visible in the latitude of New York, carefully noting everything that it seemed might interest amateur star-gazers. All the objects thus observed have not been included in this book, lest the multiplicity of details should deter or discourage the very readers for whom it was specially written. -
Studying Hydrogen Emission Lines from Classical T Tauri Stars: Telluric Line Removal, Physical Conditions in the Emitting Gas, and Reddening
Studying Hydrogen Emission Lines from Classical T Tauri Stars: Telluric Line Removal, Physical Conditions in the Emitting Gas, and Reddening Dissertation zur Erlangung des Doktorgrades des Fachbereichs Physik der Universit¨atHamburg vorgelegt von Natascha Rudolf aus Hamburg Hamburg 2014 ii Gutachter der Dissertation: Prof. Dr. J¨urgenH. M. M. Schmitt Prof. Dr. Ralph Neuh¨auser Gutachter der Disputation: Prof. Dr. Robi Banerjee Dr. Frederic V. Hessman Datum der Disputation: 26. Juni 2014 Vorsitzender des Pr¨ufungsausschusses: Dr. Robert Baade Vorsitzende des Promotionsausschusses: Prof. Dr. Daniela Pfannkuche Dekan der MIN Fakult¨at: Prof. Dr. Heinrich Graener iii Zusammenfassung W¨ahrendihrer Entstehung durchlaufen Sterne verschiedene Entwicklungsphasen, bevor sie die Hauptreihe erreichen. Sie bilden sich durch den gravitativen Kollaps von molekularen Wolken. Die Erhaltung des Drehimpulses erfordert es, dass die Massenakkretion nicht radial, sondern von einer Scheibe aus stattfindet. Sterne mit niedriger Masse, die sich in einer Entwicklungsphase befinden, in der sich das meiste Material in der Scheibe befindet und der Stern nicht mehr in der Wolke verborgen ist, werden klassische T Tauri Sterne (CTTS) genannt. Diese Arbeit befasst sich mit der zirkumstellaren Umgebung dieser Sterne. Die Untersuchungen basieren auf VLT/X-Shooter-Spektren von 20 Sternen mit unterschiedlichen Spektraltypen und Massenakkretionsraten. Die X-Shooter-Spektren decken zeitgleich einen Spektralbereich von etwa 3000 A˚ bis etwa 25 000 A˚ bei einer mittleren Aufl¨osung(R ∼ 10 000) ab. Ein wichtiger Schritt der Datenreduktion ist die Entfernung der tellurischen Linien, die die Erdatmosph¨aredem Spektrum hinzuf¨ugt.An Stelle der Nutzung beobachteter tellurischer Standardsterne verwende ich Modelle der atmosph¨arischen Transmission, die an die Wetterbe- dingungen zum Zeitpunkt der Beobachtung angepasst sind, um diese Kontamination zu entfer- nen. -
Andromeda Andromeda Andromeda Andromeda Andromeda Aries
Andromeda M31: Great Andromeda Galaxy. Spiral. 3.28 mag. 2.54 Mly. (Plus M31 & M101). Andromeda NGC 891: Spiral galaxy. Caldwell 23. 9.80 mag. 32 Mly. Andromeda Upsilon And: Double Star. Four planets orbit primary. 4.09 mag. 44.0 ly. Andromeda Gamma1,2 And: Double Star. (Almach). 2.17 mag. 390 ly. Andromeda VX And: Carbon star. 8.51 mag. 1300 ly. Aries Lambda Arietis: Double Star. 4.79 mag. 130 lys. Aries Gamma Arietis: Double Star. (Mesarthim). 3.9 mag. 204 ly. Augria B34: Dark Nebula. Two degrees west of M37. About ½ degree in size. Auriga IC 405: (Flaming Star Nebula). Caldwell 31. 5 ly across. 1500 ly distant. Auriga UU Aurigae Carbon star. 5.42 mag. 1800 ly Bootes Mu1,Mu2: A fine triple. (Alkalurops). 6.5 mag. 120 ly. Bootes Epsilon Boo: Double Star. (Izar). 5.12 mag. 203 ly. Bootes Xi Bootis: Double Star. One of closest systems to Earth. 4.76 mag. 21.8 ly. Bootes i Bootis: Double Star. 4.83 mag. 40.8 ly. Bootes Delta Bootis: Double Star. 3.47 mag. 122ly. Camelopardalis 1 Cam: Double Star. 6.94 mag. 2900 ly. Camelopardalis NGC 2403: Intermediate spiral galaxy. Caldwell 7. 8.9 mag. 8 Mly. Northern spiral arm connects to the star forming region NGC 2404 Cancer Iota Cancri: Double Star. Mag 3.93. 300 ly. Cancer Zeta Cancri: Multiple Star System. (Tegmen). 4.67 mag. 83 ly. Cancer M67: Open Cluster. 6.90 mag. 2600 ly. 12 ly diameter. 4 billion yrs old. Cancer M67 Open cluster. One of oldest. -
Observing List
day month year Epoch 2000 local clock time: 2.00 Observing List for 17 11 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 58 286 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 40 283 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 48 295 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 59 279 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 32 301 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 44 292 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 44 291 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 44 293 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 56 279 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 62 285 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 30 300 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 35 308 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 47 258 Aries 1 Arietis 6.2 7.2 2.8 fine yellow & pale blue pair 1 50.1 22 17 57 250 Aries 30 Arietis 6.6 7.4 38.6 pleasing yellow pair 2 37 24 39 59 253 Aries 33 Arietis 5.5 8.4 28.6 yellowish-white & blue pair 2 40.7 27 4 59 239 Aries 48, Epsilon Arietis 5.2 5.5 1.5 white pair, splittable @ 150x 2 59.2 21 20 46 254 Aries 5, Gamma Arietis (*262) 4.8 4.8 7.8 nice bluish-white pair 1 53.5 19 18 49 258 Aries 9, Lambda Arietis -
R Alteola Okt R Altqisic Taiyde Tuarasc Il 2013
Ralteolaokt Raltqisic Taiyde Tuarascil 2013 Astronomy and Astrophysics Research Report 2013 Presented to the Governing Board of the School of Cosmic Physics on 28 March 2014 Contents 1 Research Work 1 1.1 High-Energy Phenomena.....................................1 1.1.1 Radiation processes....................................1 1.1.2 High Energy Radiation of Astrophysical sources....................2 1.1.3 HESS related activity....................................5 1.1.4 Electromagnetic Cascades, UHECR, and Neutrinos..................5 1.1.5 High energy emission from binary systems.......................8 1.2 General Theory...........................................9 1.2.1 The problem of small angular scale structure in the cosmic ray anisotropy data.9 1.2.2 Magnetic field generation in shock precursors..................... 10 1.2.3 Analytic Solution for Self-regulated Collective Escape of Cosmic Rays from Their Acceleration Sites...................................... 10 1.3 Star Formation........................................... 11 1.3.1 Characterization of Infrared Dark Clouds: NH3 Observations of an Absorption- contrast Selected IRDC Sample.............................. 11 1.3.2 X-Shooter spectroscopy of young stellar objects: Impact of chromospheric emis- sion on accretion rate estimates............................. 11 1.3.3 An Empirical Correction for Activity Effects on the Temperatures, Radii, and Es- timated Masses of Low-Mass Stars and Brown Dwarfs................ 12 1.3.4 Long-Term Monitoring of Accretion and Outflows in Young Stellar Objects: Search- ing for the Temporal Connection............................. 12 1.3.5 Non-thermal Radio Emission from Young Stellar Object Outflows......... 13 1.3.6 Very Large Array Observations of DG Tau’s Radio Jet: A Highly Collimated Ther- mal Outflow......................................... 13 1.3.7 New brown dwarf discs in Upper Scorpius observed with WISE..........