Evolution of Dust and Ice Features Around Fu Orionis Objects1 S
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The Observer's Handbook for 1912
T he O bservers H andbook FOR 1912 PUBLISHED BY THE ROYAL ASTRONOMICAL SOCIETY OF CANADA E d i t e d b y C. A, CHANT FOURTH YEAR OF PUBLICATION TORONTO 198 C o l l e g e St r e e t Pr in t e d fo r t h e So c ie t y 1912 T he Observers Handbook for 1912 PUBLISHED BY THE ROYAL ASTRONOMICAL SOCIETY OF CANADA TORONTO 198 C o l l e g e St r e e t Pr in t e d fo r t h e S o c ie t y 1912 PREFACE Some changes have been made in the Handbook this year which, it is believed, will commend themselves to observers. In previous issues the times of sunrise and sunset have been given for a small number of selected places in the standard time of each place. On account of the arbitrary correction which must be made to the mean time of any place in order to get its standard time, the tables given for a particualar place are of little use any where else, In order to remedy this the times of sunrise and sunset have been calculated for places on five different latitudes covering the populous part of Canada, (pages 10 to 21), while the way to use these tables at a large number of towns and cities is explained on pages 8 and 9. The other chief change is in the addition of fuller star maps near the end. These are on a large enough scale to locate a star or planet or comet when its right ascension and declination are given. -
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. -
Nov 2016 Newsletter
Volume22, Issue 3 NWASNEWS November 2016 Newsletter for the Wiltshire, Swindon, Beckington WHAT DO WANT FROM YOUR SOCIETY? Astronomical Societies and Salisbury Plain Firstly can I welcome our returning In the early years there may have been Wiltshire Society Page 2 speaker Philip Perkins who last came to more beginners experiences, especially us when we met over the road in the WI where I was learning the hard way myself, Swindon Stargazers 3 hall. not worried about putting my mistakes to the society so, hopefully, they may learn Beckington and SPOG 4 His imaging of the night sky is really in- from my mistakes. spirational, making the transition from Space Place What kind of plan- 5 film (hyposensitising film was no joke) Would somebody like to write a beginners ets could be at Proxima then moving over to digital. piece every month? It doesn't have to be Centauri. all your own work. His work can be seen on his website Space News: Falcon X, 6-13 Astrocruise.com. He has an observatory Saturn’s hex changes colour. in the south of France, but also does a lot At last we have our darker skies with Mars probe crash site. of imaging from here in Wiltshire near longer nights, it may bring cold and some How many planets in Milky Way Aldbourne. cloud, but did you know there are more Pluto and Charon data at last cloudy nights in August than in Decem- Argentine 30tonne meteorite ber? It is just a case of wrapping up warm Formation of the Earth What I have noticed is the drop in sub- and getting out there. -
Arxiv:0706.2206V1 [Astro-Ph] 14 Jun 2007 1983; Beichman Et Al
Accepted to the Astrophysical Journal Supplemental Series Preprint typeset using LATEX style emulateapj v. 08/22/09 A CASE STUDY OF LOW-MASS STAR FORMATION Jonathan J. Swift Institute for Astronomy, 2680 Woodlawn Dr., Honolulu, HI 96822-1897: [email protected] William J. Welch Department of Astronomy and Radio Astronomy Laboratory, University of California, 601 Campbell Hall, Berkeley, CA 94720-3411 Accepted to the Astrophysical Journal Supplemental Series ABSTRACT This article synthesizes observational data from an extensive program aimed toward a comprehensive understanding of star formation in a low-mass star-forming molecular cloud. New observations and published data spanning from the centimeter wave band to the near infrared reveal the high and low density molecular gas, dust, and pre-main sequence stars in L1551. The total cloud mass of ∼ 160 M contained within a 0.9 pc has a dynamical timescale, tdyn = 1:1 Myr. Thirty-five pre-main sequence stars with masses from ∼ 0:1 to 1.5 M are selected to be members of the L1551 association constituting a total of 22 ± 5 M of stellar mass. The observed star formation efficiency, SFE = 12%, while the total efficiency, SFEtot, is estimated to fall between 9 and 15%. L1551 appears to have been forming stars for several tdyn with the rate of star formation increas- ing with time. Star formation has likely progressed from east to west, and there is clear evidence that another star or stellar system will form in the high column density region to the northwest of L1551 IRS5. High-resolution, wide-field maps of L1551 in CO isotopologue emission display the structure of the molecular cloud at 1600 AU physical resolution. -
Searching for Gas Emission Lines in Spitzer Infrared Spectrograph \(IRS
A&A 528, A22 (2011) Astronomy DOI: 10.1051/0004-6361/201015622 & c ESO 2011 Astrophysics Searching for gas emission lines in Spitzer Infrared Spectrograph (IRS) spectra of young stars in Taurus C. Baldovin-Saavedra1,2, M. Audard1,2, M. Güdel3,L.M.Rebull4,D.L.Padgett4, S. L. Skinner5, A. Carmona1,2,A.M.Glauser6,7, and S. B. Fajardo-Acosta8 1 ISDC Data Centre for Astrophysics, Université de Genève, 16 chemin d’Ecogia, 1290 Versoix, Switzerland e-mail: [email protected] 2 Observatoire Astronomique de l’Université de Genève, 51 chemin de Maillettes, 1290 Sauverny, Switzerland 3 University of Vienna, Department of Astronomy, Türkenschanzstrasse 17, 1180 Vienna, Austria 4 Spitzer Science Center, California Institute of Technology, 220-6 1200 East California Boulevard, CA 91125 Pasadena, USA 5 Center for Astrophysics and Space Astronomy, University of Colorado, CO 80309-0389 Boulder, USA 6 ETH Zürich, 27 Wolfgang-Pauli-Str., 8093 Zürich, Switzerland 7 UK Astronomy Technology Centre, Royal Observatory, Blackford Hill, EH3 9HJ Edinburgh, UK 8 IPAC, California Institute of Technology, 770 South Wilson Avenue, CA 91125 Pasadena, USA Received 19 August 2010 / Accepted 14 January 2011 ABSTRACT Context. Our knowledge of circumstellar disks has traditionally been based on studies of dust. However, gas dominates the disk mass and its study is key to our understanding of accretion, outflows, and ultimately planet formation. The Spitzer Space Telescope provides access to gas emission lines in the mid-infrared, providing crucial new diagnostics of the physical conditions in accretion disks and outflows. Aims. We seek to identify gas emission lines in mid-infrared spectra of 64 pre-main-sequence stars in Taurus. -
July OBSERVER(220Dpi)
THE OBSERVER OF THE TWIN CITY AMATEUR ASTRONOMERS Volume 45, Number 7 July 2020 INSIDE THIS ISSUE: 1«Editor’s Choice: Image of the Month – Messier 27 2«President’s Note 2«NCRAL’s Season Messier Mini Marathons 3«Calendar of Astronomical Events – July 2020 3«New & Renewing Members/Dues Blues/E-Mail List 4«This Month’s Phases of the Moon 4«This Month’s Solar Phenomena 4«AstroBits – News from Around the TCAA 6«Waynesville Observatory Use Policy Statement 7«CDK 24” Telescope Coming Online at WO 7«Celestron NexStar 11” Telescope Donated to TCAA 8«TCAA Image Gallery 9«Maintenance Work at Waynesville Observatory 10«Did You Know? 11«TCAA Active on Facebook 11«July 2020 with Jeffrey L. Hunt 23«Renewing Your TCAA Membership 23«Online Public Talks for 2020 24«TCAA Treasurer’s Report as of June 26, 2020 The TCAA is an affiliate of the Astronomical League as well as its North Central Region. For more information about the TCAA, be certain to visit the TCAA website at http://www.tcaa.us/ Visit http://www.astroleague.org for additional information about the Astronomical League and its EDITOR’S CHOICE: IMAGE OF THE MONTH – MESSIER 27 numerous membership benefits, including observing programs. This image of M27 (Dumbbell Nebula) was taken by Scott and Emily Wade and Deva Chatrathi. Scott writes, “Here’s an image of M27 Also, visit the NCRAL website at that was captured on the evenings of 6/23 (Emily & Scott) and 6/25 http://ncral.wordpress.com for in- (Deva & Scott) using the CDK 17” telescope with the QHY600 formation about our North Central camera and RGB filters. -
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. -
Astronomical Coordinate Systems
Appendix 1 Astronomical Coordinate Systems A basic requirement for studying the heavens is being able to determine where in the sky things are located. To specify sky positions, astronomers have developed several coordinate systems. Each sys- tem uses a coordinate grid projected on the celestial sphere, which is similar to the geographic coor- dinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth’s equator). Each coordinate system is named for its choice of fundamental plane. The Equatorial Coordinate System The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the most closely related to the geographic coordinate system because they use the same funda- mental plane and poles. The projection of the Earth’s equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles onto the celestial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate sys- tems: the geographic system is fixed to the Earth and rotates as the Earth does. The Equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but it’s really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec. for short). It measures the angle of an object above or below the celestial equator. -
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. -
1949 Handbook of the British Astronomical Association
THE HANDBOOK OF THE BRITISH ASTRONOMICAL ASSOCIATION 1 9 4 9 1948 NOVEMBER Price to Members 3s. N on Members 5s. CONTENTS Preface ... ... ... ... ... ... ... 1 Planetary Diagram ... ... ... ' ... 2 V i s i b i l i t y o f P l a n e t s ....................................................................... ........................................................................ 3 Tim e Reckoning .........................! ............................ ........................................................................ 4 S u n , 1 9 4 9 ............................................................................................................................................................... 5 Eclipses, 1949 .................................................................... .. ............................_ .................................. 8 M o o n , 1 9 4 9 . ....................................................................... ............................ 9 L i b r a t i o n ............................................................................................. .................................................. 1 0 O b s e r v a t i o n o f O c c u l t a t i o n s . .................................................................................................................... 1 0 L unar O ccultations, 1949 ........................... .................................................. 1 2 A p p e a r a n c e o f P l a n e t s ................................................................... ....................................................................