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HVS 7 – a Chemically Peculiar Hyper-Velocity Star⋆ N
Astronomy & Astrophysics manuscript no. hvs7 c ESO 2008 June 24, 2008 L E HVS 7 – a chemically peculiar hyper-velocity star⋆ N. Przybilla1, M. F. Nieva1, A. Tillich1, U. Heber1, K. Butler2, and W. R. Brown3 1 Dr. Remeis-Sternwarte Bamberg, Sternwartstr. 7, D-96049 Bamberg, Germany 2 Universit¨atssternwarte M¨unchen, Scheinerstr. 1, D-81679 M¨unchen, Germany 3 Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138, USA Received... ; accepted ... ABSTRACT Context. Hyper-velocity stars are suggested to originate from the dynamical interaction of binary stars with the supermassive black hole in the Galactic centre (GC), which accelerates one component of the binary to beyond the Galactic escape velocity. Aims. The evolutionary status and GC origin of the hyper-velocity star SDSS J113312.12+010824.9 (aka HVS 7) is constrained from a detailed study of its stellar parameters and chemical composition. Methods. High-resolution spectra of HVS 7 obtained with UVES on the ESO VLT were analysed using state-of-the-art NLTE/LTE modelling techniques that can account for a chemically-peculiar composition via opacity sampling. Results. Instead of the expected slight enrichments of α-elements and near-solar iron, huge chemical peculiarities of all elements are apparent. The helium abundance is very low (<1/100 solar), C, N and O are below the detection limit, i.e they are underabundant (.1/3 to <1/100 solar). Heavier elements, however, are overabundant: the iron group by a factor of ∼10, P, Co and Cl by factors ∼40, 80 and 440 and rare-earth elements and mercury even by ∼10 000. -
THE 1000 BRIGHTEST HIPASS GALAXIES: H I PROPERTIES B
The Astronomical Journal, 128:16–46, 2004 July A # 2004. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE 1000 BRIGHTEST HIPASS GALAXIES: H i PROPERTIES B. S. Koribalski,1 L. Staveley-Smith,1 V. A. Kilborn,1, 2 S. D. Ryder,3 R. C. Kraan-Korteweg,4 E. V. Ryan-Weber,1, 5 R. D. Ekers,1 H. Jerjen,6 P. A. Henning,7 M. E. Putman,8 M. A. Zwaan,5, 9 W. J. G. de Blok,1,10 M. R. Calabretta,1 M. J. Disney,10 R. F. Minchin,10 R. Bhathal,11 P. J. Boyce,10 M. J. Drinkwater,12 K. C. Freeman,6 B. K. Gibson,2 A. J. Green,13 R. F. Haynes,1 S. Juraszek,13 M. J. Kesteven,1 P. M. Knezek,14 S. Mader,1 M. Marquarding,1 M. Meyer,5 J. R. Mould,15 T. Oosterloo,16 J. O’Brien,1,6 R. M. Price,7 E. M. Sadler,13 A. Schro¨der,17 I. M. Stewart,17 F. Stootman,11 M. Waugh,1, 5 B. E. Warren,1, 6 R. L. Webster,5 and A. E. Wright1 Received 2002 October 30; accepted 2004 April 7 ABSTRACT We present the HIPASS Bright Galaxy Catalog (BGC), which contains the 1000 H i brightest galaxies in the southern sky as obtained from the H i Parkes All-Sky Survey (HIPASS). The selection of the brightest sources is basedontheirHi peak flux density (Speak k116 mJy) as measured from the spatially integrated HIPASS spectrum. 7 ; 10 The derived H i masses range from 10 to 4 10 M . -
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 -
Für Astronomie Nr
für Astronomie Nr. 28 Zeitschrift der Vereinigung der Sternfreunde e.V. / VdS DAS WELTALL Orionnebel DU LEBST DARIN – ENTDECKE ES! Computerastronomie Internationales Jahr der Astronomie INTERNATIONALES ISSN 1615 - 0880 www.vds-astro.de I/ 2009 ASTRONOMIEJAHR [email protected] • www.astro-shop.com Tel.: 040/5114348 • Fax: 040/5114594 Eiffestr. 426 • 20537 Hamburg Astroart 4.0 The Night Sky Observer´s Guide Photoshop Astronomy Die aktuellste Version Dieses hilfreiche Werk Der Autor arbeitet seit fast 10 Jahren mit Photo- des bekannten Bildbe- dient der erfolg- shop, um seine Astrofotos zu bearbeiten. Die arbeitungspro- reichen Vorbereitung dabei gemachten Erfahrungen hat er in diesem grammes gibt es jetzt einer abwechslungs- speziell auf die Bedürfnisse des Amateurastro- mit interessanten reichen Deep-Sky- nomen zugeschnitte- neuen Funktionen. Nacht. Sortiert nach nen Buch gesammelt. Moderne Dateifor- Sternbildern des Die behandelten The- men sind unter ande- mate wie DSLR-RAW Sommer- und Win- rem: die technische werden unterstützt, terhimmels nden Ausstattung, Farbma- Bilder können sich detaillierte NEU nagement, Histo- durch automa- Beschreibungen Südhimmel gramme, Maskie- 3. Band tische Sternfelderken- zu hunderten rungstechniken, nung direkt überlagert werden, was die Bild- Galaxien, Nebeln, Oenen Stern- und Addition mehrerer feldrotation vernachlässigbar macht. Auch die Kugelhaufen. Der Teleskopanblick jedes Bilder, Korrektur von Bearbeitung von Farbbildern wurde erweitert. Objekts ist beschrieben und mit einem Hin- Vignettierungen, Besonderes Augenmerk liegt auf der Erken- weis bezüglich der verwendeten Optik verse- Farbhalos, Deformationen oder nung und Behandlung von Pixelfehlern der hen. 2 Bände mit insgesamt 446 Fotos, 827 überbelichteten Sternen, LRGB und vieles Aufnahme-Chips. Zeichnungen, 143 Tabellen und 431 Sternkar- mehr. Auf der beigefügten DVD benden sich 90 alle im Buch besprochenen und verwendeten Update ten. -
Issue No. 72, April 2012 ISSN 1323-6326
CSIRO ASTroNOMY AND SPacE SciENCE www.csiro.au ATNF News Issue No. 72, April 2012 ISSN 1323-6326 CSIRO Astronomy and Space Science — Undertaking world-leading astronomical research and operator of the Australia Telescope National Facility. Editorial Welcome to the April 2012 edition of ATNF forthcoming changes to the ATNF website. News. We review two recent workshops held at ATNF headquarters in Marsfield and we Regular readers will have noticed that this welcome our newest postdoctoral staff. edition has a fresh new appearance. We are in the process of updating the ‘visual Four science articles give a snapshot of identity’ of all CSIRO communications the latest radio astronomy research being including ATNF News, a flagship publication conducted with the ATNF. These include: of CSIRO Astronomy and Space Science An investigation into the neutral gas of (CASS). While the newsletter’s appearance ◆ the blue compact dwarf galaxy NGC 5253 has changed, we will continue to bring you by Ángel R. López-Sánchez and Bärbel news and research results related to CSIRO’s Koribalski Australia Telescope National Facility. A report on constraining the fundamental We start this edition by acknowledging ◆ constants of physics through astronomical Michelle Storey and George Hobbs, two observations of rotational transitions CASS staff members who have recently of methanol by Simon Ellingsen and received external awards for their collaborators contributions to radio astronomy. An ATCA survey of molecular gas in We then feature the recent progress that ◆ high-z radio galaxies by Bjorn Emonts and has been made on the construction of collaborators, and ASKAP and the Murchison Widefield Array, and CSIRO’s contribution to the next phase ◆ Ray Norris’ account of witnessing the of planning for the international Square birth of a quasar. -
Making a Sky Atlas
Appendix A Making a Sky Atlas Although a number of very advanced sky atlases are now available in print, none is likely to be ideal for any given task. Published atlases will probably have too few or too many guide stars, too few or too many deep-sky objects plotted in them, wrong- size charts, etc. I found that with MegaStar I could design and make, specifically for my survey, a “just right” personalized atlas. My atlas consists of 108 charts, each about twenty square degrees in size, with guide stars down to magnitude 8.9. I used only the northernmost 78 charts, since I observed the sky only down to –35°. On the charts I plotted only the objects I wanted to observe. In addition I made enlargements of small, overcrowded areas (“quad charts”) as well as separate large-scale charts for the Virgo Galaxy Cluster, the latter with guide stars down to magnitude 11.4. I put the charts in plastic sheet protectors in a three-ring binder, taking them out and plac- ing them on my telescope mount’s clipboard as needed. To find an object I would use the 35 mm finder (except in the Virgo Cluster, where I used the 60 mm as the finder) to point the ensemble of telescopes at the indicated spot among the guide stars. If the object was not seen in the 35 mm, as it usually was not, I would then look in the larger telescopes. If the object was not immediately visible even in the primary telescope – a not uncommon occur- rence due to inexact initial pointing – I would then scan around for it. -
Ngc Catalogue Ngc Catalogue
NGC CATALOGUE NGC CATALOGUE 1 NGC CATALOGUE Object # Common Name Type Constellation Magnitude RA Dec NGC 1 - Galaxy Pegasus 12.9 00:07:16 27:42:32 NGC 2 - Galaxy Pegasus 14.2 00:07:17 27:40:43 NGC 3 - Galaxy Pisces 13.3 00:07:17 08:18:05 NGC 4 - Galaxy Pisces 15.8 00:07:24 08:22:26 NGC 5 - Galaxy Andromeda 13.3 00:07:49 35:21:46 NGC 6 NGC 20 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 7 - Galaxy Sculptor 13.9 00:08:21 -29:54:59 NGC 8 - Double Star Pegasus - 00:08:45 23:50:19 NGC 9 - Galaxy Pegasus 13.5 00:08:54 23:49:04 NGC 10 - Galaxy Sculptor 12.5 00:08:34 -33:51:28 NGC 11 - Galaxy Andromeda 13.7 00:08:42 37:26:53 NGC 12 - Galaxy Pisces 13.1 00:08:45 04:36:44 NGC 13 - Galaxy Andromeda 13.2 00:08:48 33:25:59 NGC 14 - Galaxy Pegasus 12.1 00:08:46 15:48:57 NGC 15 - Galaxy Pegasus 13.8 00:09:02 21:37:30 NGC 16 - Galaxy Pegasus 12.0 00:09:04 27:43:48 NGC 17 NGC 34 Galaxy Cetus 14.4 00:11:07 -12:06:28 NGC 18 - Double Star Pegasus - 00:09:23 27:43:56 NGC 19 - Galaxy Andromeda 13.3 00:10:41 32:58:58 NGC 20 See NGC 6 Galaxy Andromeda 13.1 00:09:33 33:18:32 NGC 21 NGC 29 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 22 - Galaxy Pegasus 13.6 00:09:48 27:49:58 NGC 23 - Galaxy Pegasus 12.0 00:09:53 25:55:26 NGC 24 - Galaxy Sculptor 11.6 00:09:56 -24:57:52 NGC 25 - Galaxy Phoenix 13.0 00:09:59 -57:01:13 NGC 26 - Galaxy Pegasus 12.9 00:10:26 25:49:56 NGC 27 - Galaxy Andromeda 13.5 00:10:33 28:59:49 NGC 28 - Galaxy Phoenix 13.8 00:10:25 -56:59:20 NGC 29 See NGC 21 Galaxy Andromeda 12.7 00:10:47 33:21:07 NGC 30 - Double Star Pegasus - 00:10:51 21:58:39 -