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October 2017 BRAS Newsletter
October 2017 Issue Next Meeting: Monday, October 9th at 7PM at HRPO nd (2 Mondays, Highland Road Park Observatory) October Program: BRAS President John Nagle will. reveal how he researches and puts together his Observing Notes column for our newsletter each. month. What's In This Issue? HRPO’s Great American Eclipse Event Summary (Page 2) President’s Message Secretary's Summary Outreach Report - FAE Light Pollution Committee Report Recent Forum Entries 20/20 Vision Campaign Messages from the HRPO Spooky Spectrum Observe The Moon Night Natural Sky Conference HRPO 20th Anniversary Observing Notes – Phoenix & Mythology Like this newsletter? See past issues back to 2009 at http://brastro.org/newsletters.html Newsletter of the Baton Rouge Astronomical Society October 2017 President’s Message The first Sidewalk Astronomy of the season was a success. We had a good time, and About 100 people (adult and children) attended. Ben Toman live streamed on the BRAS Facebook page. See his description in this newsletter. A copy of the proposed, revised By-Laws should be in your mail soon. Read through them, and any proposed changes need to be communicated to me before the November meeting. Wally Pursell (who wrote the original and changed by-laws) and I worked last year on getting the By-Laws updated to the current BRAS policies, and we hope the revised By-Laws will need no revisions for a long time. We need more Globe at Night observations – we are behind in the observations compared to last year at this time. We also need observations of variable stars to help in a school project by a new BRAS member, Shreya. -
The Extragalactic Distance Scale
The Extragalactic Distance Scale Published in "Stellar astrophysics for the local group" : VIII Canary Islands Winter School of Astrophysics. Edited by A. Aparicio, A. Herrero, and F. Sanchez. Cambridge ; New York : Cambridge University Press, 1998 Calibration of the Extragalactic Distance Scale By BARRY F. MADORE1, WENDY L. FREEDMAN2 1NASA/IPAC Extragalactic Database, Infrared Processing & Analysis Center, California Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA 91125, USA 2Observatories, Carnegie Institution of Washington, 813 Santa Barbara St., Pasadena CA 91101, USA The calibration and use of Cepheids as primary distance indicators is reviewed in the context of the extragalactic distance scale. Comparison is made with the independently calibrated Population II distance scale and found to be consistent at the 10% level. The combined use of ground-based facilities and the Hubble Space Telescope now allow for the application of the Cepheid Period-Luminosity relation out to distances in excess of 20 Mpc. Calibration of secondary distance indicators and the direct determination of distances to galaxies in the field as well as in the Virgo and Fornax clusters allows for multiple paths to the determination of the absolute rate of the expansion of the Universe parameterized by the Hubble constant. At this point in the reduction and analysis of Key Project galaxies H0 = 72km/ sec/Mpc ± 2 (random) ± 12 [systematic]. Table of Contents INTRODUCTION TO THE LECTURES CEPHEIDS BRIEF SUMMARY OF THE OBSERVED PROPERTIES OF CEPHEID -
Spitzer IRAC Observations of Star Formation in N159 in The
Spitzer IRAC Observations of Star Formation in N159 in the LMC Terry J. Jones, Charles E. Woodward, Martha L. Boyer, Robert D. Gehrz, and Elisha Polomski Department of Astronomy, University of Minnesota, 116 Church Street S.E., Minneapolis, MN 55455 tjj, chelsea, mboyer, gehrz, [email protected] Received ; accepted arXiv:astro-ph/0410708v1 28 Oct 2004 –2– ABSTRACT We present observations of the giant HII region complex N159 in the LMC using IRAC on the Spitzer Space Telescope. One of the two objects previously identified as protostars in N159 has an SED consistent with classification as a Class I young stellar object (YSO) and the other is probably a Class I YSO as well, making these two stars the youngest stars known outside the Milky Way. We identify two other sources that may also be Class I YSOs. One component, N159AN, is completely hidden at optical wavelengths, but is very prominent in 6 the infrared. The integrated luminosity of the entire complex is L ≈ 9 × 10 L⊙, consistent with the observed radio emission assuming a normal Galactic initial mass function (IMF). There is no evidence for a red supergiant population indica- tive of an older burst of star formation. The N159 complex is 50 pc in diameter, larger in physical size than typical HII regions in the Milky Way with comparable luminosity. We argue that all of the individual components are related in their star formation history. The morphology of the region is consistent with a wind blown bubble ≈ 1 − 2 Myr-old that has initiated star formation now taking place at the rim. -
SAGE−Spectroscopy: the Life Cycle of Dust and Gas in the Large Magellanic Cloud
Spitzer Space Telescope Legacy Science Proposal #40159. SAGE−Spectroscopy: The life cycle of dust and gas in the Large Magellanic Cloud Principal Investigator: Alexander G.G.M. Tielens (ES, ISM, SF) Institution: NASA Ames Research Center Electronic mail: [email protected] Technical Contact: Ciska Markwick−Kemper, University of Manchester (SC, ES, ISM) Co−Investigators: Jean−Philippe Bernard, CESR, Toulouse (ISM, SF) Robert Blum, NOAO (ES) Martin Cohen , UC−Berkeley (ES, SC) Catharinus Dijkstra, unaff. (ES) Karl Gordon, U. Arizona (IRSE, MP, ME, ISM, SF) Varoujan Gorjian, NASA−JPL (SC) Jason Harris, U. Arizona (SC, ES) Sacha Hony, CEA, Saclay (ISM, SF) Joseph Hora, CfA−Harvard (ES) Remy Indebetouw, U. Virginia (IRSE, SF) Eric Lagadec, U. of Manchester (ES) Jarron Leisenring, U. of Virginia (IRSP, ES) Suzanne Madden, CEA,Saclay (ISM, SF) Massimo Marengo, CfA−Harvard (SC) Mikako Matsuura, NAO, Japan (ES) Margaret Meixner, STScI (DB, ES, SC, SF) Knut Olsen, NOAO (ES) Roberta Paladini, IPAC/CalTech (SF) Deborah Paradis, CESR, Toulouse (ISM) William T. Reach, IPAC/CalTech (IRSE, ISM) Douglas Rubin, CEA, Saclay (ISM, SF) Marta Sewilo, STSci (DB, SF, SC) Greg Sloan, Cornell (IRSP, SC, ES) Angela Speck, U. Missouri (ES) Sundar Srinivasan, Johns Hopkins U. (ES) Schuyler Van Dyk, Spitzer Science Center (IRSP, SC) Jacco van Loon, U. of Keele (MP, ES) Uma Vijh, STSci and U. of Toledo (DB, ES, ISM) Kevin Volk, Gemini Observatory (ES, SC) Barbara Whitney, Space Science Institute (SF, SC) Albert Zijlstra, U. of Manchester (ES) Science Category: Extragalactic: local group galaxies Observing Modes: IRS Staring, IRS Mapping, MIPS SED Hours Requested: 224.4 Proprietary Period(days): 0 Abstract: Cycling of matter between the ISM and stars drives the evolution of a galaxy’s visible matter and its emission characteristics. -
Stellar Clusters in Dwarf Galaxies
A&A 448, 471–478 (2006) Astronomy DOI: 10.1051/0004-6361:20052949 & c ESO 2006 Astrophysics Stellar clusters in dwarf galaxies L. Vanzi1 and M. Sauvage2 1 European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago, Chile e-mail: [email protected] 2 CEA/DSM/DAPNIA/Service d’Astrophysique – UMR AIM, CE Saclay, 91191 Gif-sur-Yvette Cedex, France e-mail: [email protected] Received 28 February 2005 / Accepted 13 October 2005 ABSTRACT We present new observations in the Ks (2.2 µm) and L (3.7 µm) infrared bands of a sample of blue dwarf galaxies with the larger aim of studying the population of massive stellar clusters, the occurrence of dust-embedded stellar clusters, and their properties. All Ks images show a rich population of clusters, but only a small fraction of them is bright in L.MostL sources have radio counterparts. We derived the luminosity function in Ks for the galaxies IC 4661 and NGC 5408, finding both to be consistent with those of similar galaxies. We also compared the number of clusters and their luminosities with the star-formation rate of the host galaxies and found no compelling evidence of correlation. We conclude that young clusters and embedded clusters are a common feature of blue dwarf galaxies and possibly of galaxies in general, we suggest that their occurrence is due to purely statistical effects rather than a phenomenon related to specific physical conditions. In this sense we expect these objects to be abundant at high red-shift. Key words. galaxies: dwarf – galaxies: starburst – galaxies: star clusters 1. -
Annual Report 1972
I I ANNUAL REPORT 1972 EUROPEAN SOUTHERN OBSERVATORY ANNUAL REPORT 1972 presented to the Council by the Director-General, Prof. Dr. A. Blaauw, in accordance with article VI, 1 (a) of the ESO Convention Organisation Europeenne pour des Recherches Astronomiques dans 1'Hkmisphtre Austral EUROPEAN SOUTHERN OBSERVATORY Frontispiece: The European Southern Observatory on La Silla mountain. In the foreground the "old camp" of small wooden cabins dating from the first period of settlement on La Silln and now gradually being replaced by more comfortable lodgings. The large dome in the centre contains the Schmidt Telescope. In the background, from left to right, the domes of the Double Astrograph, the Photo- metric (I m) Telescope, the Spectroscopic (1.>2 m) Telescope, and the 50 cm ESO and Copen- hagen Telescopes. In the far rear at right a glimpse of the Hostel and of some of the dormitories. Between the Schmidt Telescope Building and the Double Astrograph the provisional mechanical workshop building. (Viewed from the south east, from a hill between thc existing telescope park and the site for the 3.6 m Telescope.) TABLE OF CONTENTS INTRODUCTION General Developments and Special Events ........................... 5 RESEARCH ACTIVITIES Visiting Astronomers ........................................ 9 Statistics of Telescope Use .................................... 9 Research by Visiting Astronomers .............................. 14 Research by ESO Staff ...................................... 31 Joint Research with Universidad de Chile ...................... -
Review Article Star Formation Histories of Dwarf Galaxies from the Colour-Magnitude Diagrams of Their Resolved Stellar Populations
Hindawi Publishing Corporation Advances in Astronomy Volume 2010, Article ID 158568, 25 pages doi:10.1155/2010/158568 Review Article Star Formation Histories of Dwarf Galaxies from the Colour-Magnitude Diagrams of Their Resolved Stellar Populations Michele Cignoni1, 2 and Monica Tosi2 1 Astronomy Department, Bologna University, Via Ranzani 1, 40127 Bologna, Italy 2 Osservatorio Astronomico di Bologna, INAF, Via Ranzani 1, 40127 Bologna, Italy Correspondence should be addressed to Michele Cignoni, [email protected] Received 5 May 2009; Accepted 12 August 2009 Academic Editor: Ulrich Hopp Copyright © 2010 M. Cignoni and M. Tosi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In this tutorial paper we summarize how the star formation (SF) history of a galactic region can be derived from the colour- magnitude diagram (CMD) of its resolved stars. The procedures to build synthetic CMDs and to exploit them to derive the SF histories (SFHs) are described, as well as the corresponding uncertainties. The SFHs of resolved dwarf galaxies of all morphological types, obtained from the application of the synthetic CMD method, are reviewed and discussed. To summarize: (1) only early-type galaxies show evidence of long interruptions in the SF activity; late-type dwarfs present rather continuous, or gasping, SF regimes; (2) a few early-type dwarfs have experienced only one episode of SF activity concentrated at the earliest epochs, whilst many others show extended or recurrent SF activity; (3) no galaxy experiencing now its first SF episode has been found yet; (4) no frequent evidence of strong SF bursts is found; (5) there is no significant difference in the SFH of dwarf irregulars and blue compact dwarfs, except for the current SF rates. -
Neutral Hydrogen in Nearby Dwarf Galaxies B¨Arbel S
Dwarf Galaxies: From the Deep Universe to the Present Proceedings IAU Symposium No. 344, 2018 c 2018 International Astronomical Union K. McQuinn & S. Stierwalt, eds. DOI: 00.0000/X000000000000000X Neutral Hydrogen in Nearby Dwarf Galaxies B¨arbel S. Koribalski CSIRO Astronomy and Space Science, Australia Telescope National Facility PO Box 76, Epping, NSW 1710, Australia email: [email protected] Abstract. Here I briefly highlight our studies of the gas content, kinematics and star formation in nearby dwarf galaxies (D < 10 Mpc) based on the `Local Volume H i Survey' (LVHIS, Koribalski et al. 2018), which was conducted with the Australia Telescope Compact Array (ATCA). The LVHIS sample consists of nearly 100 galaxies, including new discoveries, spanning a large diversity in size, shape, mass and degree of peculiarity. The hydrogen properties of dwarf galaxies in two nearby groups, Sculptor and CenA / M83, are analysed and compared with many rather isolated dwarf galaxies. Around 10% of LVHIS galaxies are transitional or mixed-type dwarf galaxies (dIrr/dSph), the formation of which is explored. | I also provide a brief update on WALLABY Early Science, where we focus on studying the H i properties of galaxies as a function of environment. WALLABY (Dec < +30 degr, z < 0:26) is conducted with the Australian SKA Pathfinder (ASKAP), a ∼6-km diameter array of 36 × 12-m dishes, each equipped with wide-field (30 sq degr) Chequerboard Phased Array Feeds. Keywords. galaxies: kinematics and dynamics | galaxies: structure | radio lines: galaxies | surveys 1. LVHIS { The Local Volume H i Survey The LVHIS project provides high-resolution H i spectral line and 20-cm radio contin- uum data products for nearly 100 nearby galaxies, based on over 2500 hours of ATCA observations. -
Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al
Noname manuscript No. (will be inserted by the editor) Weighing stars from birth to death: mass determination methods across the HRD Aldo Serenelli · Achim Weiss · Conny Aerts · George C. Angelou · David Baroch · Nate Bastian · Paul G. Beck · Maria Bergemann · Joachim M. Bestenlehner · Ian Czekala · Nancy Elias-Rosa · Ana Escorza · Vincent Van Eylen · Diane K. Feuillet · Davide Gandolfi · Mark Gieles · L´eoGirardi · Yveline Lebreton · Nicolas Lodieu · Marie Martig · Marcelo M. Miller Bertolami · Joey S.G. Mombarg · Juan Carlos Morales · Andr´esMoya · Benard Nsamba · KreˇsimirPavlovski · May G. Pedersen · Ignasi Ribas · Fabian R.N. Schneider · Victor Silva Aguirre · Keivan G. Stassun · Eline Tolstoy · Pier-Emmanuel Tremblay · Konstanze Zwintz Received: date / Accepted: date A. Serenelli Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E- 08193, Spain and Institut d'Estudis Espacials de Catalunya (IEEC), Carrer Gran Capita 2, Barcelona, E-08034, Spain E-mail: [email protected] A. Weiss Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany C. Aerts Institute of Astronomy, Department of Physics & Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium and Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands G.C. Angelou Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany D. Baroch J. C. Morales I. Ribas Institute of· Space Sciences· (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E-08193, arXiv:2006.10868v2 [astro-ph.SR] 9 Apr 2021 Spain and Institut d'Estudis Espacials de Catalunya (IEEC), C/Gran Capit`a2-4, E-08034 2 Serenelli, Weiss, Aerts et al. -
Lecture 7: "Basics of Star Formation and Stellar Nucleosynthesis" Outline
Lecture 7: "Basics of Star Formation and Stellar Nucleosynthesis" Outline 1. Formation of elements in stars 2. Injection of new elements into ISM 3. Phases of star-formation 4. Evolution of stars Mark Whittle University of Virginia Life Cycle of Matter in Milky Way Molecular clouds New clouds with gravitationally collapse heavier composition to form stellar clusters of stars are formed Molecular cloud Stars synthesize Most massive stars evolve He, C, Si, Fe via quickly and die as supernovae – nucleosynthesis heavier elements are injected in space Solar abundances • Observation of atomic absorption lines in the solar spectrum • For some (heavy) elements meteoritic data are used Solar abundance pattern: • Regularities reflect nuclear properties • Several different processes • Mixture of material from many, many stars 5 SolarNucleosynthesis abundances: key facts • Solar• Decreaseabundance in abundance pattern: with atomic number: - Large negative anomaly at Be, B, Li • Regularities reflect nuclear properties - Moderate positive anomaly around Fe • Several different processes 6 - Sawtooth pattern from odd-even effect • Mixture of material from many, many stars Origin of elements • The Big Bang: H, D, 3,4He, Li • All other nuclei were synthesized in stars • Stellar nucleosynthesis ⇔ 3 key processes: - Nuclear fusion: PP cycles, CNO bi-cycle, He burning, C burning, O burning, Si burning ⇒ till 40Ca - Photodisintegration rearrangement: Intense gamma-ray radiation drives nuclear rearrangement ⇒ 56Fe - Most nuclei heavier than 56Fe are due to neutron -
MEMORIA IAC 2013 Pero No Todo Son Balances Positivos
MEMORIA 2013 “INSTITUTO DE ASTROFÍSICA DE CANARIAS” EDITA: Unidad de Comunicación y Cultura Científica (UC3) del Instituto de Astrofísica de Canarias (IAC) MAQUETA E IMPRIME: Printisur DEPÓSITO LEGAL: 7- PRESENTACIÓN Índice general 8- CONSORCIO PÚBLICO IAC 12- LOS OBSERVATORIOS DE CANARIAS 14- - Observatorio del Teide (OT) 15- - Observatorio del Roque de los Muchachos (ORM) 16- COMISIÓN PARA LA ASIGNACIÓN DE TIEMPO (CAT) 20- ACUERDOS 22- GRAN TELESCOPIO CANARIAS (GTC) 26- ÁREA DE INVESTIGACIÓN 29- - Estructura del Universo y Cosmología 47- - El Universo Local 80- - Física de las estrellas, Sistemas Planetarios y Medio Interestelar 107- - El Sol y el Sistema Solar 137- - Instrumentación y Espacio 161- - Otros 174- ÁREA DE INSTRUMENTACIÓN 174- - Ingeniería 188- - Producción 192- - Oficina de Proyectos Institucionales y Transferencia de Resultados de Investigación (OTRI) 201- ÁREA DE ENSEÑANZA 201- - Cursos de doctorado 203- - Seminarios científicos 207- - Coloquios 207- - Becas 209- - Tesis doctorales 209- - XXIV Escuela de Invierno: ”Aplicaciones astrofísicas de las lentes gravitatorias” 211- ADMINISTRACIÓN DE SERVICIOS GENERALES 211- - Instituto de Astrofísica 213- - Oficina Técnica para la Protección de la Calidad del Cielo (OTPC) 216- - Observatorio del Teide 216- - Observatorio del Roque de los Muchachos 217- - Centro de Astrofísica de la Palma 218- - Ejecución del Presupuesto 2013 219- GABINETE DE DIRECCIÓN 219- - Ediciones 220- - Carteles 220- - Comunicación y divulgación 232- - Web 234- - Visitas a las instalaciones del IAC 237- -
Referierte Publikationen
14 Publikationslisten Referierte Publikationen Abadie, J., B.P. Abbott, R. Abbott, ..., A. von Kienlin, A. Adams, J.J., K. Gebhardt, G.A. Blanc, M.H. Fabricius, G.J. Rau, and X.-L. Zhang: Search for Gravitational Waves As- Hill, J.D. Murphy, R.C.E. van den Bosch and G. van de sociated with Gamma-Ray Bursts during LIGO Science Ven: The Central Dark Matter Distribution of NGC 2976. Run 6 and Virgo Science Runs 2 and 3. Ap. J. 760, 12 Ap. J. 745, 92 (2012). (2012). Agarwal, B., S. Khochfar, J.L. Johnson, E. Neistein, C. Ackermann, M., M. Ajello, A. Albert, …, A.W. Strong, et Dalla Vecchia and M. Livio: Ubiquitous seeding of super- al.: Anisotropies in the diffuse gamma-ray background massive black holes by direct collapse. Mon. Not. R. As- measured by the Fermi LAT. Physical Review D 85, tron. Soc. 425, 2854-2871 (2012). 083007 (2012). Aghanim, N., M. Arnaud, M. Ashdown, ..., H. Böhringer, Ackermann, M., M. Ajello, A. Albert, …, A.W. Strong, et al.: et al.: Planck intermediate results. I. Further validation Publisher's Note: Anisotropies in the diffuse gamma-ray of new Planck clusters with XMM-Newton. Astron. Astro- background measured by the Fermi LAT [Phys. Rev. D 85, phys. 543, A102 (2012). 083007 (2012)]. Physical Review D 85, 109901 (2012). Ahn, C.P., R. Alexandroff, C. Allende Prieto, …, A. Beifi ori, Ackermann, M., M. Ajello, A. Allafort, …, A.W. Strong, …, F. Montesano, …, A.G. Sanchez, et al.: The Ninth Data et al.: Gamma-Ray Observations of the Orion Molecular Release of the Sloan Digital Sky Survey: First Spectrosco- Clouds with the Fermi Large Area Telescope.