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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 . -
1. Introduction
THE ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 122:109È150, 1999 May ( 1999. The American Astronomical Society. All rights reserved. Printed in U.S.A. GALAXY STRUCTURAL PARAMETERS: STAR FORMATION RATE AND EVOLUTION WITH REDSHIFT M. TAKAMIYA1,2 Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637; and Gemini 8 m Telescopes Project, 670 North Aohoku Place, Hilo, HI 96720 Received 1998 August 4; accepted 1998 December 21 ABSTRACT The evolution of the structure of galaxies as a function of redshift is investigated using two param- eters: the metric radius of the galaxy(Rg) and the power at high spatial frequencies in the disk of the galaxy (s). A direct comparison is made between nearby (z D 0) and distant(0.2 [ z [ 1) galaxies by following a Ðxed range in rest frame wavelengths. The data of the nearby galaxies comprise 136 broad- band images at D4500A observed with the 0.9 m telescope at Kitt Peak National Observatory (23 galaxies) and selected from the catalog of digital images of Frei et al. (113 galaxies). The high-redshift sample comprises 94 galaxies selected from the Hubble Deep Field (HDF) observations with the Hubble Space Telescope using the Wide Field Planetary Camera 2 in four broad bands that range between D3000 and D9000A (Williams et al.). The radius is measured from the intensity proÐle of the galaxy using the formulation of Petrosian, and it is argued to be a metric radius that should not depend very strongly on the angular resolution and limiting surface brightness level of the imaging data. It is found that the metric radii of nearby and distant galaxies are comparable to each other. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate 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 is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it 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 of course 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. The longitud inal angle is called the right ascension (RA for short). -
Observing List Evening of 2011 Dec 25 at Boyden Observatory
Southern Skies Binocular list Observing List Evening of 2011 Dec 25 at Boyden Observatory Sunset 19:20, Twilight ends 20:49, Twilight begins 03:40, Sunrise 05:09, Moon rise 06:47, Moon set 20:00 Completely dark from 20:49 to 03:40. New Moon. All times local (GMT+2). Listing All Classes visible above 2 air mass and in complete darkness after 20:49 and before 03:40. Cls Primary ID Alternate ID Con Mag Size Distance RA 2000 Dec 2000 Begin Optimum End S.A. Ur. 2 PSA Difficulty Optimum EP Open Collinder 227 Melotte 101 Car 8.4 15.0' 6500 ly 10h42m12.0s -65°06'00" 01:32 03:31 03:54 25 210 40 challenging Glob NGC 2808 Car 6.2 14.0' 26000 ly 09h12m03.0s -64°51'48" 21:57 03:08 04:05 25 210 40 detectable Open IC 2602 Collinder 229 Car 1.6 100.0' 520 ly 10h42m58.0s -64°24'00" 23:20 03:31 04:07 25 210 40 obvious Open Collinder 246 Melotte 105 Car 9.4 5.0' 7200 ly 11h19m42.0s -63°29'00" 01:44 03:33 03:57 25 209 40 challenging Open IC 2714 Collinder 245 Car 8.2 14.0' 4000 ly 11h17m27.0s -62°44'00" 01:32 03:33 03:57 25 209 40 challenging Open NGC 2516 Collinder 172 Car 3.3 30.0' 1300 ly 07h58m04.0s -60°45'12" 20:38 01:56 04:10 24 200 30 obvious Open NGC 3114 Collinder 215 Car 4.5 35.0' 3000 ly 10h02m36.0s -60°07'12" 22:43 03:27 04:07 25 199 40 easy Neb NGC 3372 Eta Carinae Nebula Car 3.0 120.0' 10h45m06.0s -59°52'00" 23:26 03:32 04:07 25 199 38 easy Open NGC 3532 Collinder 238 Car 3.4 50.0' 1600 ly 11h05m39.0s -58°45'12" 23:47 03:33 04:08 25 198 38 easy Open NGC 3293 Collinder 224 Car 6.2 6.0' 7600 ly 10h35m51.0s -58°13'48" 23:18 03:32 04:08 25 199 -
Machine Learning for Star Cluster Identification∗ Submitted to Apj
Draft version December 1, 2020 Typeset using LATEX default style in AASTeX63 StarcNet: Machine Learning for Star Cluster Identification∗ Gustavo Perez´ ,1 Matteo Messa ,2 Daniela Calzetti ,2 Subhransu Maji ,1 Dooseok E. Jung ,2 Angela Adamo ,3 and Mattia Siressi3 1Department of Computer Science University of Massachusetts Amherst 40 Governors Drive Amherst, MA 01003, USA 2Department of Astronomy University of Massachusetts Amherst 710 North Pleasant Street Amherst, MA 01003, USA 3Department of Astronomy, Oskar Klein Centre, Stockholm University, AlbaNova University Centre, SE-106 91 Stockholm, Sweden (Received July 1, 2020; Revised; Accepted) Submitted to ApJ ABSTRACT We present a machine learning (ML) pipeline to identify star clusters in the multi{color images of nearby galaxies, from observations obtained with the Hubble Space Telescope as part of the Treasury Project LEGUS (Legacy ExtraGalactic Ultraviolet Survey). StarcNet (STAR Cluster classification NETwork) is a multi{scale convolutional neural network (CNN) which achieves an accuracy of 68.6% (4 classes)/86.0% (2 classes: cluster/non{cluster) for star cluster classification in the images of the LEGUS galaxies, nearly matching human expert performance. We test the performance of StarcNet by applying pre{trained CNN model to galaxies not included in the training set, finding accuracies similar to the reference one. We test the effect of StarcNet predictions on the inferred cluster properties by comparing multi{color luminosity functions and mass{age plots from catalogs produced by StarcNet and by human{labeling; distributions in luminosity, color, and physical characteristics of star clusters are similar for the human and ML classified samples. There are two advantages to the ML approach: (1) reproducibility of the classifications: the ML algorithm's biases are fixed and can be measured for subsequent analysis; and (2) speed of classification: the algorithm requires minutes for tasks that humans require weeks to months to perform. -
Information to Users
INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter fece, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely afreet reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell & Howell Information Company 300 North Zed) Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 A STUDY OF ATTENUATION EFFECTS IN HIGHLY INCLINED SPIRAL GALAXIES DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Leslie E. -
Synapses of Active Galactic Nuclei: Comparing X-Ray and Optical Classifications Using Artificial Neural Networks?
A&A 567, A92 (2014) Astronomy DOI: 10.1051/0004-6361/201322592 & c ESO 2014 Astrophysics Synapses of active galactic nuclei: Comparing X-ray and optical classifications using artificial neural networks? O. González-Martín1;2;??, D. Díaz-González3, J. A. Acosta-Pulido1;2, J. Masegosa4, I. E. Papadakis5;6, J. M. Rodríguez-Espinosa1;2, I. Márquez4, and L. Hernández-García4 1 Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, 38205 La Laguna, Spain e-mail: [email protected] 2 Departamento de Astrofísica, Universidad de La Laguna (ULL), 38205 La Laguna, Spain 3 Shidix Technologies, 38320, La Laguna, Spain 4 Instituto de Astrofísica de Andalucía, CSIC, C/ Glorieta de la Astronomía s/n, 18005 Granada, Spain 5 Physics Department, University of Crete, PO Box 2208, 710 03 Heraklion, Crete, Greece 6 IESL, Foundation for Research and Technology, 711 10 Heraklion, Crete, Greece Received 2 September 2013 / Accepted 3 April 2014 ABSTRACT Context. Many classes of active galactic nuclei (AGN) have been defined entirely through optical wavelengths, while the X-ray spectra have been very useful to investigate their inner regions. However, optical and X-ray results show many discrepancies that have not been fully understood yet. Aims. The main purpose of the present paper is to study the synapses (i.e., connections) between X-ray and optical AGN classifications. Methods. For the first time, the newly implemented efluxer task allowed us to analyse broad band X-ray spectra of a sample of emission-line nuclei without any prior spectral fitting. Our sample comprises 162 spectra observed with XMM-Newton/pn of 90 lo- cal emission line nuclei in the Palomar sample. -
Atlas Menor Was Objects to Slowly Change Over Time
C h a r t Atlas Charts s O b by j Objects e c t Constellation s Objects by Number 64 Objects by Type 71 Objects by Name 76 Messier Objects 78 Caldwell Objects 81 Orion & Stars by Name 84 Lepus, circa , Brightest Stars 86 1720 , Closest Stars 87 Mythology 88 Bimonthly Sky Charts 92 Meteor Showers 105 Sun, Moon and Planets 106 Observing Considerations 113 Expanded Glossary 115 Th e 88 Constellations, plus 126 Chart Reference BACK PAGE Introduction he night sky was charted by western civilization a few thou - N 1,370 deep sky objects and 360 double stars (two stars—one sands years ago to bring order to the random splatter of stars, often orbits the other) plotted with observing information for T and in the hopes, as a piece of the puzzle, to help “understand” every object. the forces of nature. The stars and their constellations were imbued with N Inclusion of many “famous” celestial objects, even though the beliefs of those times, which have become mythology. they are beyond the reach of a 6 to 8-inch diameter telescope. The oldest known celestial atlas is in the book, Almagest , by N Expanded glossary to define and/or explain terms and Claudius Ptolemy, a Greco-Egyptian with Roman citizenship who lived concepts. in Alexandria from 90 to 160 AD. The Almagest is the earliest surviving astronomical treatise—a 600-page tome. The star charts are in tabular N Black stars on a white background, a preferred format for star form, by constellation, and the locations of the stars are described by charts. -
Optically Identified Supernova Remnants in the Nearby Spiral Galaxies NGC 5204, NGC 5585, NGC 6946, M81, and M101
Dartmouth College Dartmouth Digital Commons Open Dartmouth: Peer-reviewed articles by Dartmouth faculty Faculty Work 9-1997 Optically Identified Supernova Remnants in the Nearby Spiral Galaxies NGC 5204, NGC 5585, NGC 6946, M81, and M101 David M. Matonick Dartmouth College Robert A. Fesen Dartmouth College Follow this and additional works at: https://digitalcommons.dartmouth.edu/facoa Part of the Stars, Interstellar Medium and the Galaxy Commons Dartmouth Digital Commons Citation Matonick, David M. and Fesen, Robert A., "Optically Identified Supernova Remnants in the Nearby Spiral Galaxies NGC 5204, NGC 5585, NGC 6946, M81, and M101" (1997). Open Dartmouth: Peer-reviewed articles by Dartmouth faculty. 2307. https://digitalcommons.dartmouth.edu/facoa/2307 This Article is brought to you for free and open access by the Faculty Work at Dartmouth Digital Commons. It has been accepted for inclusion in Open Dartmouth: Peer-reviewed articles by Dartmouth faculty by an authorized administrator of Dartmouth Digital Commons. For more information, please contact [email protected]. THE ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 112:49È107, 1997 September ( 1997. The American Astronomical Society. All rights reserved. Printed in U.S.A. OPTICALLY IDENTIFIED SUPERNOVA REMNANTS IN THE NEARBY SPIRAL GALAXIES NGC 5204, NGC 5585, NGC 6946, M81, AND M101 DAVID M. MATONICK AND ROBERT A. FESEN Department of Physics and Astronomy, 6127 Wilder Laboratory, Dartmouth College, Hanover, NH 03755 Received 1997 January 24; accepted 1997 April 11 ABSTRACT We present the results of an optical search for supernova remnants (SNRs) in the spiral galaxies NGC 5204, NGC 5585, NGC 6946, M81, and M101. Using the criterion that emission nebulae with [S II]/ Ha º 0.45 are identiÐed as SNRs, we found three SNRs in NGC 5204, Ðve in NGC 5585, 27 in NGC 6946, 41 in M81, and 93 in M101. -
Aktuelles Am Sternenhimmel Mai 2020 Antares
A N T A R E S NÖ AMATEURASTRONOMEN NOE VOLKSSTERNWARTE Michelbach Dorf 62 3074 MICHELBACH NOE VOLKSSTERNWARTE 3074 MICHELBACH Die VOLKSSTERNWARTE im Zentralraum Niederösterreich 04.05.1961 Alan Shepard mit Mercury 3 1. Amerikaner im All (suborbitaler Flug) 07.05.1963 Erste Transatlantische Farbfernsehübertragung mittels Telstar 2 (USA) 10.05.1916 Einsteins Relativitätstheorie wird veröffentlicht (Deutschland) 13.05.1973 Die amerikanische Raumstation Skylab 1 wird gestartet 14.05.1960 Sputnik I ist erstes Raumschiff in einer Umlaufbahn (UdSSR) 16.05.1974 Erster geostationärer Wettersatellit SMS 1 wird gestartet 17.05.1969 Apollo 10: Start zur ersten Erprobung der Mondfähre im Mondorbit 20.05.1984 Erster kommerzieller Flug der europäischen Trägerrakete Ariane 23.05.1960 Start des ersten militärischen Frühwarnsystems Midas 2 25.05.2012 Erster privater Raumtransporter, die Dragonkapsel der Firma Space X, dockt an die Internationalen Raumstation ISS an 30.05.1986 Erster Flug einer Ariane 2 AKTUELLES AM STERNENHIMMEL MAI 2020 Die Frühlingssternbilder Löwe, Jungfrau und Bärenhüter mit den Coma- und Virgo- Galaxienhaufen stehen hoch im Süden, der Große Bär hoch im Zenit. Nördliche Krone und Herkules sind am Osthimmel auffindbar, Wega und Deneb sind die Vorboten des Sommerhimmels. Merkur kann in der zweiten Monatshälfte am Abend aufgefunden werden; Venus verabschiedet sich vom Abendhimmel. Mars, Jupiter und Saturn sind die Planeten der zweiten Nachthälfte. INHALT Auf- und Untergangszeiten Sonne und Mond Fixsternhimmel Monatsthema – Spektraltypen, -
Galaxy Flow in the Canes Venatici I Cloud
Astronomy & Astrophysics manuscript no. IKarachentsev November 2, 2018 (DOI: will be inserted by hand later) Galaxy Flow in the Canes Venatici I Cloud ⋆ I. D. Karachentsev1, M. E. Sharina1,10, A. E. Dolphin2, E. K. Grebel3, D. Geisler4, P. Guhathakurta5, P. W. Hodge6, V. E. Karachentseva7, A. Sarajedini8, and P. Seitzer9 1 Special Astrophysical Observatory, Russian Academy of Sciences, N. Arkhyz, KChR, 369167, Russia 2 Kitt Peak National Observatory, National Optical Astronomy Observatories, P.O. Box 26732, Tucson, AZ 85726, USA 3 Max-Planck-Institut f¨ur Astronomie, K¨onigstuhl 17, D-69117 Heidelberg, Germany 4 Departamento de F´ısica, Grupo de Astronom´ıa, Universidad de Concepci´on, Casilla 160-C, Concepci´on, Chile 5 UCO/Lick Observatory, University of California at Santa Cruz, Santa Cruz, CA 95064, USA 6 Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA 7 Astronomical Observatory of Kiev University, 04053, Observatorna 3, Kiev, Ukraine 8 Department of Astronomy, University of Florida, Gainesville, FL 32611, USA 9 Department of Astronomy, University of Michigan, 830 Dennison Building, Ann Arbor, MI 48109, USA 10 Isaac Newton Institute, Chile, SAO Branch arXiv:astro-ph/0210414v1 18 Oct 2002 Received: August 8, 2002 Abstract. We present an analysis of Hubble Space Telescope/WFPC2 images of eighteen galaxies in the Canes Venatici I cloud. We derive their distances from the luminosity of the tip of the red giant branch stars with a typical accuracy of ∼ 12 %. The resulting distances are 3.9 Mpc (UGC 6541), 4.9 Mpc (NGC 3738), 3.0 Mpc (NGC 3741), 4.5 Mpc (KK 109), > 6.3 Mpc (NGC 4150), 4.2 Mpc (UGC 7298), 4.5 Mpc (NGC 4244), 4.6 Mpc (NGC 4395), 4.9 Mpc (UGC 7559), 4.2 Mpc (NGC 4449), 4.4 Mpc (UGC 7605), 4.6 Mpc (IC 3687), 4.7 Mpc (KK 166), 4.7 Mpc (NGC 4736), 4.2 Mpc (UGC 8308), 4.3 Mpc (UGC 8320), 4.6 Mpc (NGC 5204), and 3.2 Mpc (UGC 8833). -
Aktuelles Am Sternenhimmel April 2020 Antares
A N T A R E S NÖ AMATEURASTRONOMEN NOE VOLKSSTERNWARTE Michelbach Dorf 62 3074 MICHELBACH NOE VOLKSSTERNWARTE 3074 MICHELBACH Die VOLKSSTERNWARTE im Zentralraum Niederösterreich 02.04.1966 Luna 10 schwenkt als 1. Sonde in einen Mondorbit ein (UdSSR) 03.04.1959 Die ersten sieben Astronauten der USA werden bekanntgegeben 10.04.1970 Start Apollo 13. Nach einer Explosion an Bord können alle 3 Astronauten mit der Mondlandefähre als Rettungsboot zur Erde zurückkehren. 12.04.1960 Start von Transit 1B: Erster Navigationssatellit im All 12.04.1961 Juri Gagarin startet als 1. Mensch mit Vostok 1 (UdSSR) ins All 15.04.1901 Wilbur Wright macht den erste Motorflug (1867 geboren) 18.04.1971 Start der 1. Weltraumstation Saljut 1 (UdSSR) 21.04.1971 Die erste Besatzung dockt an der ersten Raumstation Saljut 1 an (UdSSR) 22.04.1967 Wladimir Komarov stirbt als erster Kosmonaut im Weltraum (Sojus 1) 23.04.1990 Weltraumteleskop Hubble wird mit dem Shuttle Flug 31 gestartet 24.04.1962 Ariel 1, der erste internationale Satellit, wird gestartet (USA, England) AKTUELLES AM STERNENHIMMEL APRIL 2020 Die Wintersternbilder gehen im Westen unter; der Große Bär steht hoch im Zenit, der Löwe im Süden, Bärenhüter und Jungfrau halten sich wie die Galaxienhaufen noch in der östlichen Himmelshälfte auf; südlich der Jungfrau stehen Becher und Rabe, über dem Südhorizont schlänget sich die unscheinbare Wasserschlange. Venus ist strahlender „Abendstern“, Mars, Jupiter und Saturn werden die Planeten der zweiten Nachthälfte. INHALT Auf- und Untergangszeiten Sonne und Mond Fixsternhimmel