Module 5: to the Galaxies and Beyond Lesson 1: the Hubble Classification of Galaxies
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A Revised View of the Canis Major Stellar Overdensity with Decam And
MNRAS 501, 1690–1700 (2021) doi:10.1093/mnras/staa2655 Advance Access publication 2020 October 14 A revised view of the Canis Major stellar overdensity with DECam and Gaia: new evidence of a stellar warp of blue stars Downloaded from https://academic.oup.com/mnras/article/501/2/1690/5923573 by Consejo Superior de Investigaciones Cientificas (CSIC) user on 15 March 2021 Julio A. Carballo-Bello ,1‹ David Mart´ınez-Delgado,2 Jesus´ M. Corral-Santana ,3 Emilio J. Alfaro,2 Camila Navarrete,3,4 A. Katherina Vivas 5 and Marcio´ Catelan 4,6 1Instituto de Alta Investigacion,´ Universidad de Tarapaca,´ Casilla 7D, Arica, Chile 2Instituto de Astrof´ısica de Andaluc´ıa, CSIC, E-18080 Granada, Spain 3European Southern Observatory, Alonso de Cordova´ 3107, Casilla 19001, Santiago, Chile 4Millennium Institute of Astrophysics, Santiago, Chile 5Cerro Tololo Inter-American Observatory, NSF’s National Optical-Infrared Astronomy Research Laboratory, Casilla 603, La Serena, Chile 6Instituto de Astrof´ısica, Facultad de F´ısica, Pontificia Universidad Catolica´ de Chile, Av. Vicuna˜ Mackenna 4860, 782-0436 Macul, Santiago, Chile Accepted 2020 August 27. Received 2020 July 16; in original form 2020 February 24 ABSTRACT We present the Dark Energy Camera (DECam) imaging combined with Gaia Data Release 2 (DR2) data to study the Canis Major overdensity. The presence of the so-called Blue Plume stars in a low-pollution area of the colour–magnitude diagram allows us to derive the distance and proper motions of this stellar feature along the line of sight of its hypothetical core. The stellar overdensity extends on a large area of the sky at low Galactic latitudes, below the plane, and in the range 230◦ <<255◦. -
Complex Stellar Populations in Massive Clusters: Trapping Stars of a Dwarf Disc Galaxy in a Newborn Stellar Supercluster
Mon. Not. R. Astron. Soc. 372, 338–342 (2006) doi:10.1111/j.1365-2966.2006.10867.x Complex stellar populations in massive clusters: trapping stars of a dwarf disc galaxy in a newborn stellar supercluster M. Fellhauer,1,3⋆ P. Kroupa2,3⋆ and N. W. Evans1⋆ 1Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA 2Argelander Institute for Astronomy, University of Bonn, Auf dem Hug¨ el 71, D-53121 Bonn, Germany 3The Rhine Stellar-Dynamical Network Accepted 2006 July 24. Received 2006 July 21; in original form 2006 April 27 ABSTRACT Some of the most-massive globular clusters of our Milky Way, such as, for example, ω Centauri, show a mixture of stellar populations spanning a few Gyr in age and 1.5 dex in metallicities. In contrast, standard formation scenarios predict that globular and open clusters form in one single starburst event of duration 10 Myr and therefore should exhibit only one age and one metallicity in its stars. Here, we investigate the possibility that a massive stellar supercluster may trap older galactic field stars during its formation process that are later detectable in the cluster as an apparent population of stars with a very different age and metallicity. With a set of numerical N-body simulations, we are able to show that, if the mass of the stellar supercluster is high enough and the stellar velocity dispersion in the cluster is comparable to the dispersion of the surrounding disc stars in the host galaxy, then up to about 40 per cent of its initial mass can be additionally gained from trapped disc stars. -
Messier Objects
Messier Objects From the Stocker Astroscience Center at Florida International University Miami Florida The Messier Project Main contributors: • Daniel Puentes • Steven Revesz • Bobby Martinez Charles Messier • Gabriel Salazar • Riya Gandhi • Dr. James Webb – Director, Stocker Astroscience center • All images reduced and combined using MIRA image processing software. (Mirametrics) What are Messier Objects? • Messier objects are a list of astronomical sources compiled by Charles Messier, an 18th and early 19th century astronomer. He created a list of distracting objects to avoid while comet hunting. This list now contains over 110 objects, many of which are the most famous astronomical bodies known. The list contains planetary nebula, star clusters, and other galaxies. - Bobby Martinez The Telescope The telescope used to take these images is an Astronomical Consultants and Equipment (ACE) 24- inch (0.61-meter) Ritchey-Chretien reflecting telescope. It has a focal ratio of F6.2 and is supported on a structure independent of the building that houses it. It is equipped with a Finger Lakes 1kx1k CCD camera cooled to -30o C at the Cassegrain focus. It is equipped with dual filter wheels, the first containing UBVRI scientific filters and the second RGBL color filters. Messier 1 Found 6,500 light years away in the constellation of Taurus, the Crab Nebula (known as M1) is a supernova remnant. The original supernova that formed the crab nebula was observed by Chinese, Japanese and Arab astronomers in 1054 AD as an incredibly bright “Guest star” which was visible for over twenty-two months. The supernova that produced the Crab Nebula is thought to have been an evolved star roughly ten times more massive than the Sun. -
Introduction to Astronomy from Darkness to Blazing Glory
Introduction to Astronomy From Darkness to Blazing Glory Published by JAS Educational Publications Copyright Pending 2010 JAS Educational Publications All rights reserved. Including the right of reproduction in whole or in part in any form. Second Edition Author: Jeffrey Wright Scott Photographs and Diagrams: Credit NASA, Jet Propulsion Laboratory, USGS, NOAA, Aames Research Center JAS Educational Publications 2601 Oakdale Road, H2 P.O. Box 197 Modesto California 95355 1-888-586-6252 Website: http://.Introastro.com Printing by Minuteman Press, Berkley, California ISBN 978-0-9827200-0-4 1 Introduction to Astronomy From Darkness to Blazing Glory The moon Titan is in the forefront with the moon Tethys behind it. These are two of many of Saturn’s moons Credit: Cassini Imaging Team, ISS, JPL, ESA, NASA 2 Introduction to Astronomy Contents in Brief Chapter 1: Astronomy Basics: Pages 1 – 6 Workbook Pages 1 - 2 Chapter 2: Time: Pages 7 - 10 Workbook Pages 3 - 4 Chapter 3: Solar System Overview: Pages 11 - 14 Workbook Pages 5 - 8 Chapter 4: Our Sun: Pages 15 - 20 Workbook Pages 9 - 16 Chapter 5: The Terrestrial Planets: Page 21 - 39 Workbook Pages 17 - 36 Mercury: Pages 22 - 23 Venus: Pages 24 - 25 Earth: Pages 25 - 34 Mars: Pages 34 - 39 Chapter 6: Outer, Dwarf and Exoplanets Pages: 41-54 Workbook Pages 37 - 48 Jupiter: Pages 41 - 42 Saturn: Pages 42 - 44 Uranus: Pages 44 - 45 Neptune: Pages 45 - 46 Dwarf Planets, Plutoids and Exoplanets: Pages 47 -54 3 Chapter 7: The Moons: Pages: 55 - 66 Workbook Pages 49 - 56 Chapter 8: Rocks and Ice: -
Midwife of the Galactic Zoo
FOCUS 30 A miniature milky way: approximately 40 million light-years away, UGC 5340 is classified as a dwarf galaxy. Dwarf galaxies exist in a variety of forms – elliptical, spheroidal, spiral, or irregular – and originate in small halos of dark matter. Dwarf galaxies contain the oldest known stars. Max Planck Research · 4 | 2020 FOCUS MIDWIFE OF THE GALACTIC ZOO TEXT: THOMAS BÜHRKE 31 IMAGE: NASA, TEAM ESA & LEGUS Stars cluster in galaxies of dramatically different shapes and sizes: elliptical galaxies, spheroidal galaxies, lenticular galaxies, spiral galaxies, and occasionally even irregular galaxies. Nadine Neumayer at the Max Planck Institute for Astronomy in Heidelberg and Ralf Bender at the Max Planck Institute for Extraterrestrial Physics in Garching investigate the reasons for this diversity. They have already identified one crucial factor: dark matter. Max Planck Research · 4 | 2020 FOCUS Nature has bestowed an overwhelming diversity upon our planet. The sheer resourcefulness of the plant and animal world is seemingly inexhaustible. When scien- tists first started to explore this diversity, their first step was always to systematize it. Hence, the Swedish naturalist Carl von Linné established the principles of modern botany and zoology in the 18th century by clas- sifying organisms. In the last century, astronomers have likewise discovered that galaxies can come in an array of shapes and sizes. In this case, it was Edwin Hubble in the mid-1920s who systematized them. The “Hubble tuning fork dia- gram” classified elliptical galaxies according to their ellipticity. The series of elliptical galaxies along the di- PHOTO: PETER FRIEDRICH agram branches off into two arms: spiral galaxies with a compact bulge along the upper branch and galaxies with a central bar on the lower branch. -
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 . -
Lecture 6: Galaxy Dynamics (Basic) Elliptical Galaxy Dynamics
Lecture 6: Galaxy Dynamics (Basic) • Basic dynamics of galaxies – Ellipticals, kinematically hot random orbit systems – Spirals, kinematically cool rotating system • Key relations: – The fundamental plane of ellipticals/bulges – The Faber-Jackson relation for ellipticals/bulges – The Tully-Fisher for spirals disks • Using FJ and TF to calculate distances – The extragalactic distance ladder – Examples 1 Elliptical galaxy dynamics • Ellipticals are triaxial spheroids • No rotation, no flattened plane • Typically we can measure a velocity dispersion, σ – I.e., the integrated motions of the stars • Dynamics analogous to a gravitational bound cloud of gas (I.e., an isothermal sphere). • I.e., dp GM(r)ρ(r) HYDROSTATIC − = EQUILIBRIUM dr r2 Check Wikipedia “Hydrostatic PRESSURE FORCE GRAVITATIONAL FORCE Equilibrium” to see PER UNIT VOLUME PER UNIT VOLUME deriiation. € 2 1 Elliptical galaxy dynamics • For an isothermal sphere gas pressure is given by: 2 Reminder from p = ρ(r)σ Thermodynamics: P=nRT/V=ρT, 1 E=(3/2)kT=(1/2)mv^2 ρ(r) ∝ r2 σ 2 GM(r) 2 ⇒ 3 ∝ 4 2σ r r r M(r) = G M(r) ∝σ 2r € 3 € Elliptical galaxy dynamics • As E/S0s are centrally concentrated if σ is measured over sufficient area M(r)=>M, I.e., Total Mass ∝σ 2r • σ is measured from either: – Radial velocity distributions from individual stellar spectra – From line widths€ in integrated galaxy spectra [See Galactic Astronomy, Binney & Merrifield for details on how these are measured in practice] 4 2 Elliptical galaxy dynamices • We have three measureable quantities: – L = luminosity (or magnitude) – Re = effective or half-light radius – σ = velocity dispersion • From these we can derive Σο the central surface brightness (nb: one of these four is redundant as its calculable from the others.) • How are these related observationally and theoretically ? x y • I.e., what does: L ∝ Σ o σ ν look like ? Σο Log logL THE FUNDAMENTAL PLANE € Logσ 5 Fundamental Plane Theory 2 (I.e., stars behaving as if isothermal sphere) IF σν ∝ M Re 2 Surf. -
Isolated Elliptical Galaxies in the Local Universe
A&A 588, A79 (2016) Astronomy DOI: 10.1051/0004-6361/201527844 & c ESO 2016 Astrophysics Isolated elliptical galaxies in the local Universe I. Lacerna1,2,3, H. M. Hernández-Toledo4 , V. Avila-Reese4, J. Abonza-Sane4, and A. del Olmo5 1 Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Av. V. Mackenna 4860, Santiago, Chile e-mail: [email protected] 2 Centro de Astro-Ingeniería, Pontificia Universidad Católica de Chile, Av. V. Mackenna 4860, Santiago, Chile 3 Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany 4 Instituto de Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264, 04510 México D. F., Mexico 5 Instituto de Astrofísica de Andalucía IAA – CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain Received 26 November 2015 / Accepted 6 January 2016 ABSTRACT Context. We have studied a sample of 89 very isolated, elliptical galaxies at z < 0.08 and compared their properties with elliptical galaxies located in a high-density environment such as the Coma supercluster. Aims. Our aim is to probe the role of environment on the morphological transformation and quenching of elliptical galaxies as a function of mass. In addition, we elucidate the nature of a particular set of blue and star-forming isolated ellipticals identified here. Methods. We studied physical properties of ellipticals, such as color, specific star formation rate, galaxy size, and stellar age, as a function of stellar mass and environment based on SDSS data. We analyzed the blue and star-forming isolated ellipticals in more detail, through photometric characterization using GALFIT, and infer their star formation history using STARLIGHT. -
An Extended Star Formation History in an Ultra-Compact Dwarf
MNRAS 451, 3615–3626 (2015) doi:10.1093/mnras/stv1221 An extended star formation history in an ultra-compact dwarf Mark A. Norris,1‹ Carlos G. Escudero,2,3,4 Favio R. Faifer,2,3,4 Sheila J. Kannappan,5 Juan Carlos Forte4,6 and Remco C. E. van den Bosch1 1Max Planck Institut fur¨ Astronomie, Konigstuhl¨ 17, D-69117 Heidelberg, Germany 2Facultad de Cs. Astronomicas´ y Geof´ısicas, UNLP, Paseo del Bosque S/N, 1900 La Plata, Argentina 3Instituto de Astrof´ısica de La Plata (CCT La Plata – CONICET – UNLP), Paseo del Bosque S/N, 1900 La Plata, Argentina 4Consejo Nacional de Investigaciones Cient´ıficas y Tecnicas,´ Rivadavia 1917, C1033AAJ Ciudad Autonoma´ de Buenos Aires, Argentina 5Department of Physics and Astronomy UNC-Chapel Hill, CB 3255, Phillips Hall, Chapel Hill, NC 27599-3255, USA 6Planetario Galileo Galilei, Secretar´ıa de Cultura, Ciudad Autonoma´ de Buenos Aires, Argentina Accepted 2015 May 29. Received 2015 May 28; in original form 2015 April 2 ABSTRACT Downloaded from There has been significant controversy over the mechanisms responsible for forming compact stellar systems like ultra-compact dwarfs (UCDs), with suggestions that UCDs are simply the high-mass extension of the globular cluster population, or alternatively, the liberated nuclei of galaxies tidally stripped by larger companions. Definitive examples of UCDs formed by either route have been difficult to find, with only a handful of persuasive examples of http://mnras.oxfordjournals.org/ stripped-nucleus-type UCDs being known. In this paper, we present very deep Gemini/GMOS spectroscopic observations of the suspected stripped-nucleus UCD NGC 4546-UCD1 taken in good seeing conditions (<0.7 arcsec). -
Elements of Astronomy and Cosmology Outline 1
ELEMENTS OF ASTRONOMY AND COSMOLOGY OUTLINE 1. The Solar System The Four Inner Planets The Asteroid Belt The Giant Planets The Kuiper Belt 2. The Milky Way Galaxy Neighborhood of the Solar System Exoplanets Star Terminology 3. The Early Universe Twentieth Century Progress Recent Progress 4. Observation Telescopes Ground-Based Telescopes Space-Based Telescopes Exploration of Space 1 – The Solar System The Solar System - 4.6 billion years old - Planet formation lasted 100s millions years - Four rocky planets (Mercury Venus, Earth and Mars) - Four gas giants (Jupiter, Saturn, Uranus and Neptune) Figure 2-2: Schematics of the Solar System The Solar System - Asteroid belt (meteorites) - Kuiper belt (comets) Figure 2-3: Circular orbits of the planets in the solar system The Sun - Contains mostly hydrogen and helium plasma - Sustained nuclear fusion - Temperatures ~ 15 million K - Elements up to Fe form - Is some 5 billion years old - Will last another 5 billion years Figure 2-4: Photo of the sun showing highly textured plasma, dark sunspots, bright active regions, coronal mass ejections at the surface and the sun’s atmosphere. The Sun - Dynamo effect - Magnetic storms - 11-year cycle - Solar wind (energetic protons) Figure 2-5: Close up of dark spots on the sun surface Probe Sent to Observe the Sun - Distance Sun-Earth = 1 AU - 1 AU = 150 million km - Light from the Sun takes 8 minutes to reach Earth - The solar wind takes 4 days to reach Earth Figure 5-11: Space probe used to monitor the sun Venus - Brightest planet at night - 0.7 AU from the -