Evolution of Proto-Galaxy-Clusters to Their Present Form: Theory and Observations
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A Multimessenger View of Galaxies and Quasars from Now to Mid-Century M
A multimessenger view of galaxies and quasars from now to mid-century M. D’Onofrio 1;∗, P. Marziani 2;∗ 1 Department of Physics & Astronomy, University of Padova, Padova, Italia 2 National Institute for Astrophysics (INAF), Padua Astronomical Observatory, Italy Correspondence*: Mauro D’Onofrio [email protected] ABSTRACT In the next 30 years, a new generation of space and ground-based telescopes will permit to obtain multi-frequency observations of faint sources and, for the first time in human history, to achieve a deep, almost synoptical monitoring of the whole sky. Gravitational wave observatories will detect a Universe of unseen black holes in the merging process over a broad spectrum of mass. Computing facilities will permit new high-resolution simulations with a deeper physical analysis of the main phenomena occurring at different scales. Given these development lines, we first sketch a panorama of the main instrumental developments expected in the next thirty years, dealing not only with electromagnetic radiation, but also from a multi-messenger perspective that includes gravitational waves, neutrinos, and cosmic rays. We then present how the new instrumentation will make it possible to foster advances in our present understanding of galaxies and quasars. We focus on selected scientific themes that are hotly debated today, in some cases advancing conjectures on the solution of major problems that may become solved in the next 30 years. Keywords: galaxy evolution – quasars – cosmology – supermassive black holes – black hole physics 1 INTRODUCTION: TOWARD MULTIMESSENGER ASTRONOMY The development of astronomy in the second half of the XXth century followed two major lines of improvement: the increase in light gathering power (i.e., the ability to detect fainter objects), and the extension of the frequency domain in the electromagnetic spectrum beyond the traditional optical domain. -
An Overview of New Worlds, New Horizons in Astronomy and Astrophysics About the National Academies
2020 VISION An Overview of New Worlds, New Horizons in Astronomy and Astrophysics About the National Academies The National Academies—comprising the National Academy of Sciences, the National Academy of Engineering, the Institute of Medicine, and the National Research Council—work together to enlist the nation’s top scientists, engineers, health professionals, and other experts to study specific issues in science, technology, and medicine that underlie many questions of national importance. The results of their deliberations have inspired some of the nation’s most significant and lasting efforts to improve the health, education, and welfare of the United States and have provided independent advice on issues that affect people’s lives worldwide. To learn more about the Academies’ activities, check the website at www.nationalacademies.org. Copyright 2011 by the National Academy of Sciences. All rights reserved. Printed in the United States of America This study was supported by Contract NNX08AN97G between the National Academy of Sciences and the National Aeronautics and Space Administration, Contract AST-0743899 between the National Academy of Sciences and the National Science Foundation, and Contract DE-FG02-08ER41542 between the National Academy of Sciences and the U.S. Department of Energy. Support for this study was also provided by the Vesto Slipher Fund. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the agencies that provided support for the project. 2020 VISION An Overview of New Worlds, New Horizons in Astronomy and Astrophysics Committee for a Decadal Survey of Astronomy and Astrophysics ROGER D. -
Galaxy Clusters: Waking Perseus
PUBLISHED: 2 JUNE 2017 | VOLUME: 1 | ARTICLE NUMBER: 164 news & views GALAXY CLUSTERS Waking Perseus The Perseus cluster contains over 1,000 a Kelvin–Helmholtz instability, which galaxies packed into a region ~3,500 kpc propagates in the wave direction and in extent. It is inevitable that such close- causes the dark area indicated in the packed galaxies will interact, and the image. This dark ‘bay-like’ feature is Chandra X-ray Observatory has observed approximately the size of the Milky Way, the beautiful result of that interaction and may be the result of a cold front in (pictured). This is no snapshot — the cluster gas: an interface where the Chandra observed the galaxy cluster temperature drops dramatically on scales for over 16 days in order to capture this much smaller than the mean free path. image. Stephen Walker and colleagues An advantage of this comparison of have retrieved the archival data and observations and simulations is that processed it to enhance the edges of (unmeasurable) physical quantities the surface brightness distribution. This can be estimated. In this case, the bay analysis, reported last year (Sanders et al., 50 kpc feature only appears in this form when Mon. Not. R. Astron. Soc. 460, 1898–1911; the ratio of the thermal pressure to the ROYAL ASTRONOMICAL SOCIETY ASTRONOMICAL ROYAL 2016), highlighted two features in the magnetic pressure is ~200, and this X-ray emission that are discussed by determination in turn allows the authors Walker et al. (Mon. Not. R. Astron. Soc. pattern seen in the image could have been to obtain an order-of-magnitude estimate 468, 2506–2516; 2017): the swirling wave generated by a passing galaxy cluster about of the magnetic field. -
The Dynamical State of the Coma Cluster with XMM-Newton?
A&A 400, 811–821 (2003) Astronomy DOI: 10.1051/0004-6361:20021911 & c ESO 2003 Astrophysics The dynamical state of the Coma cluster with XMM-Newton? D. M. Neumann1,D.H.Lumb2,G.W.Pratt1, and U. G. Briel3 1 CEA/DSM/DAPNIA Saclay, Service d’Astrophysique, L’Orme des Merisiers, Bˆat. 709, 91191 Gif-sur-Yvette, France 2 Science Payloads Technology Division, Research and Science Support Dept., ESTEC, Postbus 299 Keplerlaan 1, 2200AG Noordwijk, The Netherlands 3 Max-Planck Institut f¨ur extraterrestrische Physik, Giessenbachstr., 85740 Garching, Germany Received 19 June 2002 / Accepted 13 December 2002 Abstract. We present in this paper a substructure and spectroimaging study of the Coma cluster of galaxies based on XMM- Newton data. XMM-Newton performed a mosaic of observations of Coma to ensure a large coverage of the cluster. We add the different pointings together and fit elliptical beta-models to the data. We subtract the cluster models from the data and look for residuals, which can be interpreted as substructure. We find several significant structures: the well-known subgroup connected to NGC 4839 in the South-West of the cluster, and another substructure located between NGC 4839 and the centre of the Coma cluster. Constructing a hardness ratio image, which can be used as a temperature map, we see that in front of this new structure the temperature is significantly increased (higher or equal 10 keV). We interpret this temperature enhancement as the result of heating as this structure falls onto the Coma cluster. We furthermore reconfirm the filament-like structure South-East of the cluster centre. -
Size and Scale Attendance Quiz II
Size and Scale Attendance Quiz II Are you here today? Here! (a) yes (b) no (c) are we still here? Today’s Topics • “How do we know?” exercise • Size and Scale • What is the Universe made of? • How big are these things? • How do they compare to each other? • How can we organize objects to make sense of them? What is the Universe made of? Stars • Stars make up the vast majority of the visible mass of the Universe • A star is a large, glowing ball of gas that generates heat and light through nuclear fusion • Our Sun is a star Planets • According to the IAU, a planet is an object that 1. orbits a star 2. has sufficient self-gravity to make it round 3. has a mass below the minimum mass to trigger nuclear fusion 4. has cleared the neighborhood around its orbit • A dwarf planet (such as Pluto) fulfills all these definitions except 4 • Planets shine by reflected light • Planets may be rocky, icy, or gaseous in composition. Moons, Asteroids, and Comets • Moons (or satellites) are objects that orbit a planet • An asteroid is a relatively small and rocky object that orbits a star • A comet is a relatively small and icy object that orbits a star Solar (Star) System • A solar (star) system consists of a star and all the material that orbits it, including its planets and their moons Star Clusters • Most stars are found in clusters; there are two main types • Open clusters consist of a few thousand stars and are young (1-10 million years old) • Globular clusters are denser collections of 10s-100s of thousand stars, and are older (10-14 billion years -
The FIRST STARS in the UNIVERSE WERE TYPICALLY MANY TIMES More Massive and Luminous Than the Sun
THEFIRST STARS IN THE UNIVERSE Exceptionally massive and bright, the earliest stars changed the course of cosmic history We live in a universe that is full of bright objects. On a clear night one can see thousands of stars with the naked eye. These stars occupy mere- ly a small nearby part of the Milky Way galaxy; tele- scopes reveal a much vaster realm that shines with the light from billions of galaxies. According to our current understanding of cosmology, howev- er, the universe was featureless and dark for a long stretch of its early history. The first stars did not appear until perhaps 100 million years after the big bang, and nearly a billion years passed before galaxies proliferated across the cosmos. Astron- BY RICHARD B. LARSON AND VOLKER BROMM omers have long wondered: How did this dramat- ILLUSTRATIONS BY DON DIXON ic transition from darkness to light come about? 4 SCIENTIFIC AMERICAN Updated from the December 2001 issue COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC. EARLIEST COSMIC STRUCTURE mmostost likely took the form of a network of filaments. The first protogalaxies, small-scale systems about 30 to 100 light-years across, coalesced at the nodes of this network. Inside the protogalaxies, the denser regions of gas collapsed to form the first stars (inset). COPYRIGHT 2004 SCIENTIFIC AMERICAN, INC. After decades of study, researchers The Dark Ages to longer wavelengths and the universe have recently made great strides toward THE STUDY of the early universe is grew increasingly cold and dark. As- answering this question. Using sophisti- hampered by a lack of direct observa- tronomers have no observations of this cated computer simulation techniques, tions. -
Constraining Cosmic Rays and Magnetic Fields in the Perseus
A&A 541, A99 (2012) Astronomy DOI: 10.1051/0004-6361/201118502 & c ESO 2012 Astrophysics Constraining cosmic rays and magnetic fields in the Perseus galaxy cluster with TeV observations by the MAGIC telescopes J. Aleksic´1,E.A.Alvarez2, L. A. Antonelli3, P. Antoranz4, M. Asensio2, M. Backes5, U. Barres de Almeida6, J. A. Barrio2, D. Bastieri7, J. Becerra González8,9, W. Bednarek10, A. Berdyugin11,K.Berger8,9,E.Bernardini12, A. Biland13,O.Blanch1,R.K.Bock6, A. Boller13, G. Bonnoli3, D. Borla Tridon6,I.Braun13, T. Bretz14,26, A. Cañellas15,E.Carmona6,28,A.Carosi3,P.Colin6,, E. Colombo8, J. L. Contreras2, J. Cortina1, L. Cossio16, S. Covino3, F. Dazzi16,27,A.DeAngelis16,G.DeCaneva12, E. De Cea del Pozo17,B.DeLotto16, C. Delgado Mendez8,28, A. Diago Ortega8,9,M.Doert5, A. Domínguez18, D. Dominis Prester19,D.Dorner13, M. Doro20, D. Eisenacher14, D. Elsaesser14,D.Ferenc19, M. V. Fonseca2, L. Font20,C.Fruck6,R.J.GarcíaLópez8,9, M. Garczarczyk8, D. Garrido20, G. Giavitto1, N. Godinovic´19,S.R.Gozzini12, D. Hadasch17,D.Häfner6, A. Herrero8,9, D. Hildebrand13, D. Höhne-Mönch14,J.Hose6, D. Hrupec19,T.Jogler6, H. Kellermann6,S.Klepser1, T. Krähenbühl13,J.Krause6, J. Kushida6,A.LaBarbera3,D.Lelas19,E.Leonardo4, N. Lewandowska14, E. Lindfors11, S. Lombardi7,, M. López2, R. López1, A. López-Oramas1,E.Lorenz13,6, M. Makariev21,G.Maneva21, N. Mankuzhiyil16, K. Mannheim14, L. Maraschi3, M. Mariotti7, M. Martínez1,D.Mazin1,6, M. Meucci4, J. M. Miranda4,R.Mirzoyan6, J. Moldón15,A.Moralejo1,P.Munar-Adrover15,A.Niedzwiecki10, D. Nieto2, K. Nilsson11,29,N.Nowak6, R. -
Clusters of Galaxy Hierarchical Structure the Universe Shows Range of Patterns of Structures on Decidedly Different Scales
Astronomy 218 Clusters of Galaxy Hierarchical Structure The Universe shows range of patterns of structures on decidedly different scales. Stars (typical diameter of d ~ 106 km) are found in gravitationally bound systems called star clusters (≲ 106 stars) and galaxies (106 ‒ 1012 stars). Galaxies (d ~ 10 kpc), composed of stars, star clusters, gas, dust and dark matter, are found in gravitationally bound systems called groups (< 50 galaxies) and clusters (50 ‒ 104 galaxies). Clusters (d ~ 1 Mpc), composed of galaxies, gas, and dark matter, are found in currently collapsing systems called superclusters. Superclusters (d ≲ 100 Mpc) are the largest known structures. The Local Group Three large spirals, the Milky Way Galaxy, Andromeda Galaxy(M31), and Triangulum Galaxy (M33) and their satellites make up the Local Group of galaxies. At least 45 galaxies are members of the Local Group, all within about 1 Mpc of the Milky Way. The mass of the Local Group is dominated by 11 11 10 M31 (7 × 10 M☉), MW (6 × 10 M☉), M33 (5 × 10 M☉) Virgo Cluster The nearest large cluster to the Local Group is the Virgo Cluster at a distance of 16 Mpc, has a width of ~2 Mpc though it is far from spherical. It covers 7° of the sky in the Constellations Virgo and Coma Berenices. Even these The 4 brightest very bright galaxies are giant galaxies are elliptical galaxies invisible to (M49, M60, M86 & the unaided M87). eye, mV ~ 9. Virgo Census The Virgo Cluster is loosely concentrated and irregularly shaped, making it fairly M88 M99 representative of the most M100 common class of clusters. -
15.1 Galaxy Formation: Introduction
15.1 Galaxy Formation: Introduction Galaxy Formation • The early stages of galaxy evolution - but there is no clear-cut boundary, and it also has two principal aspects: assembly of the mass, and conversion of gas into stars • Must be related to large-scale (hierarchical) structure formation, plus the dissipative processes - it is a very messy process, much more complicated than LSS formation and growth • Probably closely related to the formation of the massive central black holes as well • Generally, we think of massive galaxy formation at high redshifts (z ~ 3 - 10, say); dwarfs may be still forming now • Observations have found populations of what must be young galaxies (ages < 1 Gyr), ostensibly progenitors of large galaxies today, at z ~ 5 - 7 • The frontier is now at z ~ 7 - 20, the so-called Reionization Era 2 A General Outline • The smallest scale density fluctuations keep collapsing, with baryons falling into the potential wells dominated by the dark matter, achieving high densties through cooling – This process starts right after the recombination at z ~ 1100 • Once the gas densities are high enough, star formation ignites – This probably happens around z ~ 20 - 30 – By z ~ 6, UV radiation from young galaxies reionizes the unverse • These protogalactic fragments keep merging, forming larger objects in a hierarchical fashion ever since then • Star formation enriches the gas, and some of it is expelled in the intergalactic medium, while more gas keeps falling in • If a central massive black hole forms, the energy release from accretion -
Second Parameter Globulars and Dwarf Spheroidals Around the Local Group Massive Galaxies: What Can They Evidence?
A&A 396, 117–123 (2002) Astronomy DOI: 10.1051/0004-6361:20021404 & c ESO 2002 Astrophysics Second parameter globulars and dwarf spheroidals around the Local Group massive galaxies: What can they evidence? V. K ravtsov Sternberg Astronomical Institute, University Avenue 13, 119899 Moscow, Russia Received 29 April 2002 / Accepted 28 August 2002 Abstract. We suggest that the majority of the “young”, so–called “second parameter” globular clusters (SPGCs) have origi- nated in the outer Galactic halo due to a process other than a tidal disruption of the dwarf spheroidal (dSph) galaxies. Basic observational evidence regarding both the dSphs and the SPGCs, coupled with the latest data about a rather large relative num- ber of such clusters among globulars in M 33 and their low portion in M 31, seems to be consistent with the suspected process. It might have taken place within the system of the most massive galaxies of the Local Group (LG) at the earliest stages of their formation and evolution. We argue that the origin and basic characteristics of the SPGCs can naturally be explained as a result of mass outflow from M 31, during and due to formation of its Pop. II stars, and subsequent accretion of gas onto its massive companions, the Galaxy and M 33. An amount of the gas accreted onto the Milky Way is expected to have been quite enough for the formation in the outer Galactic halo not only of the clusters under consideration but also a number of those dSph galaxies which are as young as the SPGCs. A less significant, but notable mass transfer from the starbursting protoGalaxy to the massive members of the LG might have occurred, too. -
The First Galaxies
First Galaxies 1 The First Galaxies Volker Bromm1 and Naoki Yoshida2 1 Department of Astronomy and Texas Cosmology Center, University of Texas, Austin, Texas 78712; email: [email protected] 2 Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8583, Japan; email: [email protected] Key Words cosmology, galaxy formation, intergalactic medium, star formation, Population III Abstract We review our current understanding of how the first galaxies formed at the end of the cosmic dark ages, a few 100 million years after the Big Bang. Modern large telescopes discovered galaxies at redshifts greater than seven, whereas theoretical studies have just reached the degree of sophistication necessary to make meaningful predictions. A crucial ingredient is the feedback exerted by the first generation of stars, through UV radiation, supernova blast waves, and chemical enrichment. The key goal is to derive the signature of the first galaxies to be observed with upcoming or planned next-generation facilities, such as the James Webb Space Telescope or Atacama Large Millimeter Array. ¿From the observational side, ongoing deep-field searches for very high-redshift galaxies begin to provide us with empirical constraints on the nature of the first galaxies. CONTENTS INTRODUCTION .................................... 2 Annu. Rev. Astron. Astrophys. 2011 49 1056-8700/97/0610-00 WHAT IS A FIRST GALAXY? ............................ 6 Theoretical Perspective .................................... 7 Observational -
Astronomy Magazine 2011 Index Subject Index
Astronomy Magazine 2011 Index Subject Index A AAVSO (American Association of Variable Star Observers), 6:18, 44–47, 7:58, 10:11 Abell 35 (Sharpless 2-313) (planetary nebula), 10:70 Abell 85 (supernova remnant), 8:70 Abell 1656 (Coma galaxy cluster), 11:56 Abell 1689 (galaxy cluster), 3:23 Abell 2218 (galaxy cluster), 11:68 Abell 2744 (Pandora's Cluster) (galaxy cluster), 10:20 Abell catalog planetary nebulae, 6:50–53 Acheron Fossae (feature on Mars), 11:36 Adirondack Astronomy Retreat, 5:16 Adobe Photoshop software, 6:64 AKATSUKI orbiter, 4:19 AL (Astronomical League), 7:17, 8:50–51 albedo, 8:12 Alexhelios (moon of 216 Kleopatra), 6:18 Altair (star), 9:15 amateur astronomy change in construction of portable telescopes, 1:70–73 discovery of asteroids, 12:56–60 ten tips for, 1:68–69 American Association of Variable Star Observers (AAVSO), 6:18, 44–47, 7:58, 10:11 American Astronomical Society decadal survey recommendations, 7:16 Lancelot M. Berkeley-New York Community Trust Prize for Meritorious Work in Astronomy, 3:19 Andromeda Galaxy (M31) image of, 11:26 stellar disks, 6:19 Antarctica, astronomical research in, 10:44–48 Antennae galaxies (NGC 4038 and NGC 4039), 11:32, 56 antimatter, 8:24–29 Antu Telescope, 11:37 APM 08279+5255 (quasar), 11:18 arcminutes, 10:51 arcseconds, 10:51 Arp 147 (galaxy pair), 6:19 Arp 188 (Tadpole Galaxy), 11:30 Arp 273 (galaxy pair), 11:65 Arp 299 (NGC 3690) (galaxy pair), 10:55–57 ARTEMIS spacecraft, 11:17 asteroid belt, origin of, 8:55 asteroids See also names of specific asteroids amateur discovery of, 12:62–63