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The Faint Globular Cluster in the Dwarf Galaxy Andromeda I
Publications of the Astronomical Society of Australia (PASA), Vol. 34, e039, 4 pages (2017). © Astronomical Society of Australia 2017; published by Cambridge University Press. doi:10.1017/pasa.2017.35 The Faint Globular Cluster in the Dwarf Galaxy Andromeda I Nelson Caldwell1, Jay Strader2,7, David J. Sand3,4, Beth Willman5 and Anil C. Seth6 1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 2Center for Data Intensive and Time Domain Astronomy, Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA 3Department of Physics and Astronomy, Texas Tech University, PO Box 41051, Lubbock, TX 79409, USA 4Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ, 85721, USA 5LSST and Steward Observatory, 933 North Cherry Avenue, Tucson, AZ 85721, USA 6Department of Physics and Astronomy, University of Utah, 115 South 1400 East, Salt Lake City, Utah 84112, USA 7Email: [email protected] (RECEIVED July 7, 2017; ACCEPTED August 10, 2017) Abstract Observations of globular clusters in dwarf galaxies can be used to study a variety of topics, including the structure of dark matter halos and the history of vigorous star formation in low-mass galaxies. We report on the properties of the faint globular cluster (MV ∼−3.4) in the M31 dwarf galaxy Andromeda I. This object adds to the growing population of low-luminosity Local Group galaxies that host single globular clusters. Keywords: galaxies: individual: Andromeda I – globular clusters: general 1 INTRODUCTION a standard cuspy halo were present, the GC would have been very unlikely to have survived to the present day. -
And Ecclesiastical Cosmology
GSJ: VOLUME 6, ISSUE 3, MARCH 2018 101 GSJ: Volume 6, Issue 3, March 2018, Online: ISSN 2320-9186 www.globalscientificjournal.com DEMOLITION HUBBLE'S LAW, BIG BANG THE BASIS OF "MODERN" AND ECCLESIASTICAL COSMOLOGY Author: Weitter Duckss (Slavko Sedic) Zadar Croatia Pусскй Croatian „If two objects are represented by ball bearings and space-time by the stretching of a rubber sheet, the Doppler effect is caused by the rolling of ball bearings over the rubber sheet in order to achieve a particular motion. A cosmological red shift occurs when ball bearings get stuck on the sheet, which is stretched.“ Wikipedia OK, let's check that on our local group of galaxies (the table from my article „Where did the blue spectral shift inside the universe come from?“) galaxies, local groups Redshift km/s Blueshift km/s Sextans B (4.44 ± 0.23 Mly) 300 ± 0 Sextans A 324 ± 2 NGC 3109 403 ± 1 Tucana Dwarf 130 ± ? Leo I 285 ± 2 NGC 6822 -57 ± 2 Andromeda Galaxy -301 ± 1 Leo II (about 690,000 ly) 79 ± 1 Phoenix Dwarf 60 ± 30 SagDIG -79 ± 1 Aquarius Dwarf -141 ± 2 Wolf–Lundmark–Melotte -122 ± 2 Pisces Dwarf -287 ± 0 Antlia Dwarf 362 ± 0 Leo A 0.000067 (z) Pegasus Dwarf Spheroidal -354 ± 3 IC 10 -348 ± 1 NGC 185 -202 ± 3 Canes Venatici I ~ 31 GSJ© 2018 www.globalscientificjournal.com GSJ: VOLUME 6, ISSUE 3, MARCH 2018 102 Andromeda III -351 ± 9 Andromeda II -188 ± 3 Triangulum Galaxy -179 ± 3 Messier 110 -241 ± 3 NGC 147 (2.53 ± 0.11 Mly) -193 ± 3 Small Magellanic Cloud 0.000527 Large Magellanic Cloud - - M32 -200 ± 6 NGC 205 -241 ± 3 IC 1613 -234 ± 1 Carina Dwarf 230 ± 60 Sextans Dwarf 224 ± 2 Ursa Minor Dwarf (200 ± 30 kly) -247 ± 1 Draco Dwarf -292 ± 21 Cassiopeia Dwarf -307 ± 2 Ursa Major II Dwarf - 116 Leo IV 130 Leo V ( 585 kly) 173 Leo T -60 Bootes II -120 Pegasus Dwarf -183 ± 0 Sculptor Dwarf 110 ± 1 Etc. -
The Major Merger Origin of the Andromeda II Kinematics
Dwarf Galaxies: From the Deep Universe to the Present Proceedings IAU Symposium No. 344, 2019 c International Astronomical Union 2019 K. B. W. McQuinn & S. Stierwalt, eds. doi:10.1017/S1743921318005276 The major merger origin of the Andromeda II kinematics Ivana Ebrov´a, Ewa L.Lokas, Sylvain Fouquet and Andr´es del Pino Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland Abstract. Prolate rotation (i.e. rotation around the long axis) has been reported for two Local Group dwarf galaxies: Andromeda II, a dwarf spheroidal satellite of M31, and Phoenix, a tran- sition type dwarf galaxy. The prolate rotation may be an exceptional indicator of a past major merger between dwarf galaxies. We showed that this type of rotation cannot be obtained in the tidal stirring scenario, in which the satellite is transformed from disky to spheroidal by tidal forces of the host galaxy. However, we successfully reproduced the observed Andromeda II kinematics in controlled, self-consistent simulations of mergers between equal-mass disky dwarf galaxies on a radial or close-to-radial orbit. In simulations including gas dynamics, star forma- tion and ram pressure stripping, we are able to reproduce more of the observed properties of Andromeda II: the unusual rotation, the bimodal star formation history and the spatial distri- bution of the two stellar populations, as well as the lack of gas. We support this scenario by demonstrating the merger origin of prolate rotation in the cosmological context for sufficiently resolved galaxies in the Illustris large-scale cosmological hydrodynamical simulation. Keywords. galaxies: dwarf, (galaxies:) Local Group, galaxies: individual (Andromeda II), galax- ies: kinematics and dynamics, galaxies: interactions, galaxies: evolution, galaxies: peculiar, methods: N-body simulations 1. -
An Observational Limit on the Dwarf Galaxy Population of the Local Group
An Observational Limit on the Dwarf Galaxy Population of the Local Group Alan B. Whiting1 Cerro Tololo Inter-American Observatory Casilla 603, La Serena, Chile [email protected] George K. T. Hau University of Durham Mike Irwin University of Cambridge Miguel Verdugo Institut f¨ur Astrophysik G¨ottingen, Germany ABSTRACT We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar survey (POSS-II) and ESO/SRC survey plates and follow-up observations performed to determine whether they were indeed overlooked members of the Local Group. arXiv:astro-ph/0610551v1 18 Oct 2006 Only two galaxies (Antlia and Cetus) were discovered this way out of 206 candi- dates. Based on internal and external comparisons, we estimate that our visual survey is more than 77% complete for objects larger than one arc minute in size and with a surface brightness greater than an extremely faint limit over the 72% of the sky not obstructed by the Milky Way. Our limit of sensitivity cannot be calculated exactly, but is certainly fainter than 25 magnitudes per square arc second in R, probably 25.5 and possibly approaching 26. We conclude that there are at most one or two Local Group dwarf galaxies fitting our observational cri- teria still undiscovered in the clear part of the sky, and roughly a dozen hidden behind the Milky Way. Our work places the “missing satellite problem” on a firm quantitative observational basis. We present detailed data on all our candidates, including surface brightness measurements. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
PDF Presentatie Van Frank
13” Frank Hol / Skyheerlen Elfje en Vixen R150S Newton in de jaren ’80 en begin ’90 vooral zon, maan, planeten en Messiers. H.T.S. – vriendin – baan – huis kopen & verbouwen trouwen – kinderen waarneemstop. Vanaf 2006 weer actief waarnemen. Focus op objecten uit de Local Group of Galaxies • 2008: Celestron C14. • 2015: 13” aluminium reisdobson. • 2017-2018-2019: 13” aluminium bino-dobson. Rocherath – SQM 21.2-21.7 13” M31 NGC206 Globulars Stofbanden Stervormings- gebieden … 13” M31 M32 NGC206 Globulars Stofbanden Stervormings- gebieden … NGC206 13” NGC205 M32 M32 is de kern van een NGC 221 galaxy die grotendeels Andromeda opgelokt is door M31. M32 is dan ook net zo X helder als de kern van M31 (met 100 miljoen sterren). Telescoop: ≈ 5.0° x 4.0° verrekijker Locatie: (bijna) overal. De helderste dwerg (vanuit onze breedte) aan de hemel: magnitude 8.1. M110 “Een elliptisch stelsel is NGC 205 dood-saai.” Andromeda Neen, kijk eens hoe mooi het stelsel aan de rand in de X donkere achtergrond verdwijnt. Een watje in de lucht! Telescoop: ≈ 5.0° x 4.0° verrekijker Locatie: (bijna) overal. Een grotere telescoop laat de randen mooi verdwijnen in de omgeving. 30’ x 25’ Burnham’s NGC185 and NGC147 “These two miniature elliptical galaxies appear to be distant Celestial companians of the Great Andromeda Galaxy M31. They are Handbook some 7 degrees north of it in the sky, and are approximately the same distance from us, about 2.2 milion light years.” Start van een lange zoektocht (die nog niet voorbij is). 13” NGC147 Twee elliptische stelsels. & NGC147 is een stuk moeilijker dan NGC185. -
Neutral Hydrogen in Local Group Dwarf Galaxies
Neutral Hydrogen in Local Group Dwarf Galaxies Jana Grcevich Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2013 c 2013 Jana Grcevich All rights reserved ABSTRACT Neutral Hydrogen in Local Group Dwarfs Jana Grcevich The gas content of the faintest and lowest mass dwarf galaxies provide means to study the evolution of these unique objects. The evolutionary histories of low mass dwarf galaxies are interesting in their own right, but may also provide insight into fundamental cosmological problems. These include the nature of dark matter, the disagreement be- tween the number of observed Local Group dwarf galaxies and that predicted by ΛCDM, and the discrepancy between the observed census of baryonic matter in the Milky Way’s environment and theoretical predictions. This thesis explores these questions by studying the neutral hydrogen (HI) component of dwarf galaxies. First, limits on the HI mass of the ultra-faint dwarfs are presented, and the HI content of all Local Group dwarf galaxies is examined from an environmental standpoint. We find that those Local Group dwarfs within 270 kpc of a massive host galaxy are deficient in HI as compared to those at larger galactocentric distances. Ram- 4 3 pressure arguments are invoked, which suggest halo densities greater than 2-3 10− cm− × out to distances of at least 70 kpc, values which are consistent with theoretical models and suggest the halo may harbor a large fraction of the host galaxy’s baryons. We also find that accounting for the incompleteness of the dwarf galaxy count, known dwarf galaxies whose gas has been removed could have provided at most 2.1 108 M of HI gas to the Milky Way. -
Draft181 182Chapter 10
Chapter 10 Formation and evolution of the Local Group 480 Myr <t< 13.7 Gyr; 10 >z> 0; 30 K > T > 2.725 K The fact that the [G]alactic system is a member of a group is a very fortunate accident. Edwin Hubble, The Realm of the Nebulae Summary: The Local Group (LG) is the group of galaxies gravitationally associ- ated with the Galaxy and M 31. Galaxies within the LG have overcome the general expansion of the universe. There are approximately 75 galaxies in the LG within a 12 diameter of ∼3 Mpc having a total mass of 2-5 × 10 M⊙. A strong morphology- density relation exists in which gas-poor dwarf spheroidals (dSphs) are preferentially found closer to the Galaxy/M 31 than gas-rich dwarf irregulars (dIrrs). This is often promoted as evidence of environmental processes due to the massive Galaxy and M 31 driving the evolutionary change between dwarf galaxy types. High Veloc- ity Clouds (HVCs) are likely to be either remnant gas left over from the formation of the Galaxy, or associated with other galaxies that have been tidally disturbed by the Galaxy. Our Galaxy halo is about 12 Gyr old. A thin disk with ongoing star formation and older thick disk built by z ≥ 2 minor mergers exist. The Galaxy and M 31 will merge in 5.9 Gyr and ultimately resemble an elliptical galaxy. The LG has −1 vLG = 627 ± 22 km s with respect to the CMB. About 44% of the LG motion is due to the infall into the region of the Great Attractor, and the remaining amount of motion is due to more distant overdensities between 130 and 180 h−1 Mpc, primarily the Shapley supercluster. -
Meteor Csillagászati Évkönyv
Ár: 3000 Ft 2016 meteor csillagászati évkönyv csillagászati évkönyv meteor ISSN 0866- 2851 2016 9 770866 285002 meteor 2016 Távcsöves Találkozó Tarján, 2016. július 28–31. www.mcse.hu Magyar Csillagászati Egyesület Fotó: Sztankó Gerda, Tarján, 2012 METEOR CSILLAGÁSZATI ÉVKÖNYV 2016 METEOR CSILLAGÁSZATI ÉVKÖNYV 2016 MCSE – 2015. OKTÓBER–NOVEMBER METEOR CSILLAGÁSZATI ÉVKÖNYV 2016 MCSE – 2015. OKTÓBER–NOVEMBER meteor csillagászati évkönyv 2016 Szerkesztette: Benkõ József Mizser Attila Magyar Csillagászati Egyesület www.mcse.hu Budapest, 2015 METEOR CSILLAGÁSZATI ÉVKÖNYV 2016 MCSE – 2015. OKTÓBER–NOVEMBER Az évkönyv kalendárium részének összeállításában közremûködött: Bagó Balázs Kaposvári Zoltán Kiss Áron Keve Kovács József Molnár Péter Sánta Gábor Sárneczky Krisztián Szabadi Péter Szabó M. Gyula Szabó Sándor Szôllôsi Attila A kalendárium csillagtérképei az Ursa Minor szoftverrel készültek. www.ursaminor.hu Szakmailag ellenôrizte: Szabados László A kiadvány a Magyar Tudományos Akadémia támogatásával készült. További támogatóink mindazok, akik az SZJA 1%-ával támogatják a Magyar Csillagászati Egyesületet. Adószámunk: 19009162-2-43 Felelôs kiadó: Mizser Attila Nyomdai elôkészítés: Kármán Stúdió, www.karman.hu Nyomtatás, kötészet: OOK-Press Kft., www.ookpress.hu Felelôs vezetô: Szathmáry Attila Terjedelem: 23 ív fekete-fehér + 12 oldal színes melléklet 2015. november ISSN 0866-2851 METEOR CSILLAGÁSZATI ÉVKÖNYV 2016 MCSE – 2015. OKTÓBER–NOVEMBER Tartalom Bevezetô ................................................... 7 Kalendárium .............................................. -
Observer's Handbook 1986
OBSERVER’S HANDBOOK 1986 EDITOR: ROY L. BISHOP THE ROYAL ASTRONOMICAL SOCIETY OF CANADA CONTRIBUTORS AND ADVISORS A l a n H. B a t t e n , Dominion Astrophysical Observatory, 5071 W. Saanich Road, Victoria, BC, Canada V8X 4M6 (The Nearest Stars). L a r r y D. B o g a n , Department of Physics, Acadia University, Wolfville, NS, Canada B0P 1X0 (Configurations of Saturn’s Satellites). Terence Dickinson, R.R. 3, Odessa, ON, Canada K0H 2H0 (The Planets). David W. Dunham, International Occultation Timing Association, P.O. Box 7488, Silver Spring, MD 20907, U.S.A. (Lunar and Planetary Occultations). Alan Dyer, Queen Elizabeth Planetarium, 10004-104 Ave., Edmonton, AB, Canada T5J 0K1 (Messier Catalogue, Deep-Sky Objects). Fred Espenak, Planetary Systems Branch, NASA-Goddard Space Flight Centre, Greenbelt, MD, U.S.A. 20771 (Eclipses and Transits). M arie Fidler, The Royal Astronomical Society of Canada, 136 Dupont St., Toronto, ON, Canada M5R 1V2 (Observatories and Planetaria). Victor Gaizauskas, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Solar Activity). R o b e r t F. G a r r is o n , David Dunlap Observatory, University of Toronto, Box 360, Richmond Hill, ON, Canada L4C 4Y6 (The Brightest Stars). Ian H alliday, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Miscellaneous Astronomical Data). W illiam Herbst, Van Vleck Observatory, Wesleyan University, Middletown, CT, U.S.A. 06457 (Galactic Nebulae). H e l e n S. H o g g , David Dunlap Observatory, University of Toronto, Box 360, Richmond Hill, ON, Canada L4C 4Y6 (Foreword). -
Tarmandroff CV Oct 2016
TAFT E. ARMANDROFF The University of Texas at Austin Telephone: 512-471-3300 2515 Speedway, Stop C1402 E-mail: [email protected] Austin, Texas 78712-1206 PROFESSIONAL HISTORY The University of Texas at Austin McDonald Observatory Director; Professor; Frank and Susan Bash Endowed Chair; June 2014-present W. M. Keck Observatory Observatory Director, 2006-2014 National Optical Astronomy Observatory Director, NOAO Gemini Science Center, and Associate Director, NOAO, 2002-2006 Acting Head, U.S. Gemini Program, 2001-2002 United States Gemini Project Manager, 2000-2006 Acting Director, NOAO Instrumentation Program, 1997 Astronomer with Tenure, 2001-2006 Associate Astronomer with Tenure, 1996-2001 Associate Astronomer, 1993-1995 Assistant Astronomer, 1989-1993 Postdoctoral Research Associate, 1987-1989 Wesleyan University Visiting Instructor, Wesleyan University, Department of Astronomy, spring & fall 1985 EDUCATION Yale University, Ph.D. in Astronomy, 1988 Yale University, M.Phil. in Astronomy, 1985 Yale University, M.S. in Astronomy, 1984 Wesleyan University, B.A. in Astronomy (with High Honors), 1982 - 1 - TAFT E. ARMANDROFF RESEARCH INTERESTS Dwarf Spheroidal Galaxies Stellar Populations in the Galaxy and Nearby Galaxies Globular Clusters Astronomical Instrumentation AWARDS AND DISTINCTIONS NASA Group Achievement Award (for Keck Observatory Archive), 2015 Sturm Memorial Lecturer, Wesleyan University, 2009 Distinguished Alumnus Award, Wesleyan University, 2007 AURA Science Award, 1999 Dirk Brouwer Prize for Contribution of Unusual -
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View Article [19]
ABSTRACT ON THE NATURE OF RADIAL DISPERSION PROFILES FOR DWARF SPHEROIDAL GALAXIES IN THE LOCAL GROUP ACCORDING TO MOND by Matthew James Walentosky Modified Newtonian Dynamics (MOND) has long been the only proposed plausible alternative to dark matter to explain mass discrepancies observed in a wide array of systems. In this thesis, the ability of MOND to ac- curately predict the radial velocity dispersion profile of Milky Way and Andromeda dwarf spheroidal galaxies (dSphs) is investigated. Using a Hermite Individual Timestep Scheme based algorithm, the motion of 10,000 stars is tracked in a Hernquist potential with a MONDian correction applied to the acceleration of each star. The observable properties are compared to present day observations and used to generate radial velocity dis- persion profiles for 5 Milky Way dSphs which can be compared to present day observations to demonstrate the accuracy of the procedure. Our calculations are in good agreement with observations. In addition, predictions are made for the radial velocity dispersion profiles for 17 Andromeda dSphs. The results of this study will show agreement between simulated, observed and calculated bulk dispersion and radial dispersion profiles. These predictions will serve as a test on the validity of MOND to either be verified or discredited by future observations. ON THE NATURE OF RADIAL DISPERSION PROFILES FOR DWARF SPHEROIDAL GALAXIES IN THE LOCAL GROUP ACCORDING TO MOND A Thesis Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the