Spiral Galaxies Like the Milky Way and Andromeda Edge on and Face On

Total Page：16

File Type：pdf, Size：1020Kb

Spiral galaxies like the Milky Way and Andromeda Edge on and face on L of Milky Way ~ few x 10 10 Lsun SDSS image by D. Hogg The Sombrero galaxy 12 kpc 40,000 light years Cartoon of the edge‐on Milky Way galaxy Palomar 5 M5 M13 M15 Images of globular clusters (GCs) (Sloan Digital Sky Survey) Leo I Dwarf Galaxy A galaxy that has 1/10 or fewer the number of stars in a Milky Way sized galaxy Dwarf galaxies Halo of dark maer 250 kpc 800,000 LY Large Magellanic cloud Wei‐Hao Wan, UH image credit (Giant) ellipcal galaxies This type of galaxy is oen found at the centers of galaxy clusters Ellipcal galaxies have relavely less gas, dust, and star formaon than spiral galaxies. They look redder because the ages of their stars are on average older than the stars in a spiral galaxy It is believed that a 2 billion solar mass black hole lives at the center of M87. Electrons accelerang along the strong magnec ﬁeld near the black hole produce this jet of light and charged parcles. Irregular galaxies forming lots of stars and/or interacng with other galaxies Large Magellanic Cloud – luminosity ~ 1/10 luminosity of the Milky Way The Mice Galaxies Many galaxies live in clusters or groups Hickson Group 87 Image taken at Gemini South Abell Cluster S0740 Image was obtained with the Hubble Space Telescope Map of the Local Group Of Galaxies A dozens of dwarf galaxies and 2 giant spirals (the Milky Way and Andromeda) NGC 205 image credit: www.noao.edu ~ 1/40 Milky Way luminosity Image credit: David W. Hogg, Michael R. Blanton, and the Sloan ~ 1/300 Milky Way Digital Sky Survey Collaboraon luminosity Image credit: David W. Hogg, Michael R. Blanton, and the Sloan ~ 1/2700 Milky Way Digital Sky Survey Collaboraon luminosity .

Copy Link

Recommended publications

Reddening Map and Recent Star Formation in the Magellanic Clouds with the Earlier Studies (E.G., Besla Et Al
Astronomy & Astrophysics manuscript no. joshi c ESO 2019 June 19, 2019 Reddening map and recent star formation in the Magellanic Clouds based on OGLE IV Cepheids Y. C. Joshi1⋆⋆⋆, A. Panchal1 1Aryabhatta Research Institute of Observational Sciences (ARIES), Manora peak, Nainital 263002, India Received: 05 November 2018; accepted 11 June 2019 Abstract Context. The reddening maps of the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) are constructed using the Cepheid Period-Luminosity (P-L) relations. Aims. We examine reddening distribution across the LMC and SMC through largest data on Classical Cepheids provided by the OGLE Phase IV survey. We also investigate the age and spatio-temporal distributions of Cepheids to understand the recent star formation history in the LMC and SMC. Methods. The V and I band photometric data of 2476 fundamental mode (FU) and 1775 ﬁrst overtone mode (FO) Cepheids in the LMC and 2753 FU and 1793 FO Cepheids in the SMC are analyzed for their P-L relations. We convert period of FO Cepheids to corresponding period of FU Cepheids before combining the two modes of Cepheids. Both galaxies are divided into small segments and combined FU and FO P-L diagrams are drawn in two bands for each segment. The reddening analysis is performed on 133 segments covering a total area of about 154.6 deg2 in the LMC and 136 segments covering a total area of about 31.3 deg2 in the SMC. By comparing with well calibrated P-L relations of these two galaxies, we determine reddening E(V − I) in each segment and equivalent reddening E(B − V) assuming the normal extinction law.
[Show full text]
Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects
Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Porto Alegre 2017 Juliana Crestani Ribeiro de Souza Spatial Distribution of Galactic Globular Clusters: Distance Uncertainties and Dynamical Effects Dissertação elaborada sob orientação do Prof. Dr. Eduardo Luis Damiani Bica, co- orientação do Prof. Dr. Charles José Bon- ato e apresentada ao Instituto de Física da Universidade Federal do Rio Grande do Sul em preenchimento do requisito par- cial para obtenção do título de Mestre em Física. Porto Alegre 2017 Acknowledgements To my parents, who supported me and made this possible, in a time and place where being in a university was just a distant dream. To my dearest friends Elisabeth, Robert, Augusto, and Natália - who so many times helped me go from "I give up" to "I’ll try once more". To my cats Kira, Fen, and Demi - who lazily join me in bed at the end of the day, and make everything worthwhile. "But, first of all, it will be necessary to explain what is our idea of a cluster of stars, and by what means we have obtained it. For an instance, I shall take the phenomenon which presents itself in many clusters: It is that of a number of lucid spots, of equal lustre, scattered over a circular space, in such a manner as to appear gradually more compressed towards the middle; and which compression, in the clusters to which I allude, is generally carried so far, as, by imperceptible degrees, to end in a luminous center, of a resolvable blaze of light." William Herschel, 1789 Abstract We provide a sample of 170 Galactic Globular Clusters (GCs) and analyse its spatial distribution properties.
[Show full text]
Galactic Astronomy with AO: Nearby Star Clusters and Moving Groups
Galactic astronomy with AO: Nearby star clusters and moving groups T. J. Davidgea aDominion Astrophysical Observatory, Victoria, BC Canada ABSTRACT Observations of Galactic star clusters and objects in nearby moving groups recorded with Adaptive Optics (AO) systems on Gemini South are discussed. These include observations of open and globular clusters with the GeMS system, and high Strehl L observations of the moving group member Sirius obtained with NICI. The latter data 2 fail to reveal a brown dwarf companion with a mass ≥ 0.02M in an 18 × 18 arcsec area around Sirius A. Potential future directions for AO studies of nearby star clusters and groups with systems on large telescopes are also presented. Keywords: Adaptive optics, Open clusters: individual (Haﬀner 16, NGC 3105), Globular Clusters: individual (NGC 1851), stars: individual (Sirius) 1. STAR CLUSTERS AND THE GALAXY Deep surveys of star-forming regions have revealed that stars do not form in isolation, but instead form in clusters or loose groups (e.g. Ref. 25). This is a somewhat surprising result given that most stars in the Galaxy and nearby galaxies are not seen to be in obvious clusters (e.g. Ref. 31). This apparent contradiction can be reconciled if clusters tend to be short-lived. In fact, the pace of cluster destruction has been measured to be roughly an order of magnitude per decade in age (Ref. 17), indicating that the vast majority of clusters have lifespans that are only a modest fraction of the dynamical crossing-time of the Galactic disk. Clusters likely disperse in response to sudden changes in mass driven by supernovae and stellar winds (e.g.
[Show full text]
Experiencing Hubble
PRESCOTT ASTRONOMY CLUB PRESENTS EXPERIENCING HUBBLE John Carter August 7, 2019 GET OUT LOOK UP • When Galaxies Collide https://www.youtube.com/watch?v=HP3x7TgvgR8 • How Hubble Images Get Color https://www.youtube.com/watch? time_continue=3&v=WSG0MnmUsEY Experiencing Hubble Sagittarius Star Cloud 1. 12,000 stars 2. ½ percent of full Moon area. 3. Not one star in the image can be seen by the naked eye. 4. Color of star reﬂects its surface temperature. Eagle Nebula. M 16 1. Messier 16 is a conspicuous region of active star formation, appearing in the constellation Serpens Cauda. This giant cloud of interstellar gas and dust is commonly known as the Eagle Nebula, and has already created a cluster of young stars. The nebula is also referred to the Star Queen Nebula and as IC 4703; the cluster is NGC 6611. With an overall visual magnitude of 6.4, and an apparent diameter of 7', the Eagle Nebula's star cluster is best seen with low power telescopes. The brightest star in the cluster has an apparent magnitude of +8.24, easily visible with good binoculars. A 4" scope reveals about 20 stars in an uneven background of fainter stars and nebulosity; three nebulous concentrations can be glimpsed under good conditions. Under very good conditions, suggestions of dark obscuring matter can be seen to the north of the cluster. In an 8" telescope at low power, M 16 is an impressive object. The nebula extends much farther out, to a diameter of over 30'. It is ﬁlled with dark regions and globules, including a peculiar dark column and a luminous rim around the cluster.
[Show full text]
Structure, Properties and Formation Histories of S0 Galaxies
Structure, Properties and Formation Histories of S0 Galaxies by Kaustubh Vaghmare Thesis Supervisor Prof. Ajit K. Kembhavi A thesis presented for the degree of Doctor of Philosophy to IUCAA & Jawaharlal Nehru University India July, 2015 Structure, Properties and Formation Histories of S0 Galaxies by Kaustubh Vaghmare c 2015 All rights reserved. Certiﬁcate This is to certify that the thesis entitled Structure, Properties and Formation Histories of S0 Galaxies submitted by Mr. Kaustubh Vaghmare for the award of the degree of Doctor of Philosophy to Jawaharlal Nehru University, New Delhi is his original work. This has not been published or submitted to any other University for any other Degree or Diploma. Pune July 30th, 2015 Prof. Ajit K. Kembhavi (Thesis Advisor & Director, IUCAA) Declaration I hereby declare that the work reported in this thesis is entirely original. This thesis is composed independently by me at the Inter-University Centre for Astronomy and Astrophysics, Pune under the supervision of Prof. Ajit K. Kembhavi. I further declare that the subject matter presented in the thesis has not previously formed the basis for the award of any degree, diploma, associateship, fellowship or any other similar title of any University or Institution. Pune July 30th, 2015 Prof. Ajit K. Kembhavi Mr. Kaustubh Vaghmare (Thesis Advisor) (Ph.D. Candidate) 3 Dedicated to ... Prathama & Prakash (my parents, my Gods) Rahul (my brother, whose ever presence with my parents and unquestioning support allowed me to work in peace) & Sneha (my beloved) 5 Acknowledgements For all students and regular visitors, it is clear that Prof. Ajit Kembhavi is one of the busiest people with frequent meetings, visits abroad, directorial duties and several other responsibilities.
[Show full text]
Arxiv:2012.05245V2 [Astro-Ph.GA] 5 May 2021
Draft version May 6, 2021 Typeset using LATEX twocolumn style in AASTeX63 Charting the Galactic acceleration field I. A search for stellar streams with Gaia DR2 and EDR3 with follow-up from ESPaDOnS and UVES Rodrigo Ibata 1 | Khyati Malhan 2 | Nicolas Martin 1, 3 | Dominique Aubert1 | Benoit Famaey 1 | Paolo Bianchini 1 | Giacomo Monari 1 | Arnaud Siebert 1 | Guillaume F. Thomas 4, 5 | Michele Bellazzini 6 | Piercarlo Bonifacio7 | Elisabetta Caffau7 | Florent Renaud 8 | arXiv:2012.05245v2 [astro-ph.GA] 5 May 2021 1Universitéde Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, F-67000 Strasbourg, France 2The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm, Sweden 3Max-Planck-Institut fürAstronomie, Königstuhl17, D-69117, Heidelberg, Germany 4Instituto de Astrof´ısica de Canarias, E-38205 La Laguna, Tenerife, Spain 5Universidad de La Laguna, Dpto. Astrof´ısica, E-38206 La Laguna, Tenerife, Spain 6INAF - Osservatorio di Astrofisica e Scienza dello Spazio, via Gobetti 93/3, I-40129 Bologna, Italy 7GEPI, Observatoire de Paris, UniversitéPSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France 8Department of Astronomy and Theoretical Physics, Lund Observatory, Box 43, 221 00 Lund, Sweden Corresponding author: Rodrigo Ibata [email protected] 2 Ibata et al. Submitted to ApJ ABSTRACT We present maps of the stellar streams detected in the Gaia Data Release 2 (DR2) and Early Data Release 3 (EDR3) catalogs using the STREAMFINDER algorithm. We also report the spectroscopic follow-up of the brighter DR2 stream members obtained with the high-resolution CFHT/ESPaDOnS and VLT/UVES spectrographs as well as with the medium-resolution NTT/EFOSC2 spectrograph.
[Show full text]
An Ultra-Deep Survey of Low Surface Brightness Galaxies in Virgo
' $ An Ultra-Deep Survey of Low Surface Brightness Galaxies in Virgo Elizabeth Helen (Lesa) Moore, BSc(Hons) Department of Physics Macquarie University May 2008 This thesis is presented for the degree of Master of Philosophy in Physics & % iii Dedicated to all the sentient beings living in galaxies in the Virgo Cluster iv CONTENTS Synopsis : :::::::::::::::::::::::::::::::::::::: xvii Statement by Candidate :::::::::::::::::::::::::::::: xviii Acknowledgements ::::::::::::::::::::::::::::::::: xix 1. Introduction ::::::::::::::::::::::::::::::::::: 1 2. Low Surface Brightness (LSB) Galaxies :::::::::::::::::::: 5 2.1 Surface Brightness and LSB Galaxies De¯ned . 6 2.2 Physical Properties and Morphology . 8 2.3 Cluster and Field Distribution of LSB Dwarfs . 14 2.4 Galaxies, Cosmology and Clustering . 16 3. Galaxies and the Virgo Cluster :::::::::::::::::::::::: 19 3.1 Importance of the Virgo Cluster . 19 3.2 Galaxy Classi¯cation . 20 3.3 Virgo Galaxy Surveys and Catalogues . 24 3.4 Properties of the Virgo Cluster . 37 3.4.1 Velocity Distribution in the Direction of the Virgo Cluster . 37 3.4.2 Distance and 3D Structure . 38 vi Contents 3.4.3 Galaxy Population . 42 3.4.4 The Intra-Cluster Medium . 45 3.4.5 E®ects of the Cluster Environment . 47 4. Virgo Cluster Membership and the Luminosity Function :::::::::: 53 4.1 The Schechter Luminosity Function . 54 4.2 The Dwarf-to-Giant Ratio (DGR) . 58 4.3 Galaxy Detection . 59 4.4 Survey Completeness . 62 4.5 Virgo Cluster Membership . 63 4.5.1 Radial Velocities . 64 4.5.2 Morphology . 65 4.5.3 Concentration Parameters . 66 4.5.4 Scale Length Limits . 68 4.5.5 The Rines-Geller Threshold .
[Show full text]
Astronomy C SSSS 2018
Astronomy C SSSS 2018 Galaxies and Stellar Evolution Written by Anna1234 School _______________________________________________________________________ Team # _______________________________________________________________________ Names _______________________________________________________________________ _______________________________________________________________________ 1 Instructions: 1. There are pictures of a number of galaxies in this test. However, as the DSO list for 2019 hasn’t been released yet, the questions asked will not require any knowledge of the galaxies themselves. 2. No partial credit will be given. Math questions will have a range of acceptable answers 3. Tiebreaker questions are in the following order: a. Section A: #2, 6, 16; Section B: #1, 5, 9; Section C: #5b, 11, 14 4. Constants that will be used throughout the test: a. 1 Parsec = 3.1 x 1016 meters b. Mass of the sun = 1.989 x 1030 kg c. Hubble’s Constant = 65 km/s/Mpc d. Absolute Magnitude of Type 1a supernova = -19.3 2 Section A: Pseudo-DSOs M87 M87 has an active galactic nucleus (AGN). 1. Briefly explain what an AGN is and what is thought to cause it. 2. In 1999, a relativistic jet of matter beaming out from the center of this galaxy was measured to be moving much faster than the speed of light. What is the name of this phenomenon? 3. The M in “M87” signifies which classification catalog? Pinwheel Galaxy 4. Using Hubble’s Classification Scheme, classify this galaxy 5. The pinwheel galaxy is known for having a high number of HII regions... a. HII regions are also known as what 2 different categories of nebulas.? b. HII regions are ionized by stars of which spectral class? 6.
[Show full text]
Disk Heating, Galactoseismology, and the Formation of Stellar Halos
galaxies Article Disk Heating, Galactoseismology, and the Formation of Stellar Halos Kathryn V. Johnston 1,*,†, Adrian M. Price-Whelan 2,†, Maria Bergemann 3, Chervin Laporte 1, Ting S. Li 4, Allyson A. Sheffield 5, Steven R. Majewski 6, Rachael S. Beaton 7, Branimir Sesar 3 and Sanjib Sharma 8 1 Department of Astronomy, Columbia University, 550 W 120th st., New York, NY 10027, USA; cfl[email protected] 2 Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ 08544, USA; [email protected] 3 Max Planck Institute for Astronomy, Heidelberg 69117, Germany; [email protected] (M.B.); [email protected] (B.S.) 4 Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA; [email protected] 5 Department of Natural Sciences, LaGuardia Community College, City University of New York, 31-10 Thomson Ave., Long Island City, NY 11101, USA; asheffi[email protected] 6 Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904, USA; [email protected] 7 The Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101, USA; [email protected] 8 Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006, Australia; [email protected] * Correspondence: [email protected]; Tel.: +1-212-854-3884 † These authors contributed equally to this work. Academic Editors: Duncan A. Forbes and Ericson D. Lopez Received: 1 July 2017; Accepted: 14 August 2017; Published: 26 August 2017 Abstract: Deep photometric surveys of the Milky Way have revealed diffuse structures encircling our Galaxy far beyond the “classical” limits of the stellar disk.
[Show full text]
(Also Designated NGC 5904) Is a Globular Cluster in the Constellation Serpens
MESSIER 5 GLOBULAR CLUSTER Messier 5 or M5 (also designated NGC 5904) is a globular cluster in the constellation Serpens. It was discovered by Gottfried Kirch in 1702 when looking for comets. It should not be confused with the much fainter and more distant globular cluster Palomar 5, which is situated nearby in the sky. DISCOVERY AND VISIBILITY M5 is, under extremely good conditions, just visible to the naked eye as a faint "star" near the star 5 Serpentis. Binoculars or small telescopes will identify the object as non-stellar while larger telescopes will show some individual stars, of which the brightest are of apparent magnitude 12.2. Charles Messier also noted it in 1764, but thought it a nebula without any stars associated with it. William Herschel was the first to resolve individual stars in the cluster in 1791, counting roughly 200. (see below for Messier 5 by Hubble Space Telescope details on William Herschel). CHARACTERISTICS Spanning 165 light-years in diameter, M5 is one of the largest known globular clusters. The gravitational sphere of influence of M5, (i.e. the volume of space in which stars are gravitationally bound to it rather than being torn away by the Milky Way's gravitational pull) has a radius of some 200 light-years. At 13 billion years old, M5 is also one of the oldest globular clusters in the Milky Way Galaxy. Its distance is about 24,500 light-years from Earth, and it contains more than 100,000 stars. NOTABLE STARS 105 stars in M5 are known to be variable in brightness, 97 of them belonging to the RR Lyrae type.
[Show full text]
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.
[Show full text]
The Mice at Play in the CALIFA Survey a Case Study of a Gas-Rich Major Merger Between first Passage and Coalescence
A&A 567, A132 (2014) Astronomy DOI: 10.1051/0004-6361/201321624 & c ESO 2014 Astrophysics The Mice at play in the CALIFA survey A case study of a gas-rich major merger between first passage and coalescence Vivienne Wild1,2, Fabian Rosales-Ortega3,4, Jesus Falcón-Barroso5,6, Rubén García-Benito7, Anna Gallazzi11,12, Rosa M. González Delgado7, Simona Bekeraite˙8, Anna Pasquali10, Peter H. Johansson13 , Begoña García Lorenzo5,6, Glenn van de Ven14, Milena Pawlik1, Enrique Peréz7, Ana Monreal-Ibero8,15 , Mariya Lyubenova14, Roberto Cid Fernandes16, Jairo Méndez-Abreu1, Jorge Barrera-Ballesteros5,6 , Carolina Kehrig7, Jorge Iglesias-Páramo7,17, Dominik J. Bomans18,19, Isabel Márquez7, Benjamin D. Johnson20, Robert C. Kennicutt21, Bernd Husemann9,8, Damian Mast23, Sebastian F. Sánchez7,17,22, C. Jakob Walcher8,JoãoAlves24, Alfonso L. Aguerri5,6, Almudena Alonso Herrero25, Joss Bland-Hawthorn26, Cristina Catalán-Torrecilla27 , Estrella Florido28, Jean Michel Gomes29, Knud Jahnke14, Á.R. López-Sánchez31,32, Adriana de Lorenzo-Cáceres1, Raffaella A. Marino29, Esther Mármol-Queraltó2, Patrick Olden1, Ascensión del Olmo7, Polychronis Papaderos29, Andreas Quirrenbach30, Jose M. Vílchez7, and Bodo Ziegler24 (Affiliations can be found after the references) Received 2 April 2013 / Accepted 27 May 2014 ABSTRACT 11 We present optical integral field spectroscopy (IFS) observations of the Mice, a major merger between two massive (10 M) gas-rich spirals NGC 4676A and B, observed between first passage and final coalescence. The spectra provide stellar and gas kinematics, ionised gas properties, and stellar population diagnostics, over the full optical extent of both galaxies with ∼1.6 kpc spatial resolution. The Mice galaxies provide a perfect case study that highlights the importance of IFS data for improving our understanding of local galaxies.
[Show full text]