An Exploration of Astronomical Techniques of Visualization
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The Global Jet Structure of the Archetypical Quasar 3C 273
galaxies Article The Global Jet Structure of the Archetypical Quasar 3C 273 Kazunori Akiyama 1,2,3,*, Keiichi Asada 4, Vincent L. Fish 2 ID , Masanori Nakamura 4, Kazuhiro Hada 3 ID , Hiroshi Nagai 3 and Colin J. Lonsdale 2 1 National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville, VA 22903, USA 2 Massachusetts Institute of Technology, Haystack Observatory, 99 Millstone Rd, Westford, MA 01886, USA; vfi[email protected] (V.L.F.); [email protected] (C.J.L.) 3 National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan; [email protected] (K.H.); [email protected] (H.N.) 4 Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan; [email protected] (K.A.); [email protected] (M.N.) * Correspondence: [email protected] Received: 16 September 2017; Accepted: 8 January 2018; Published: 24 January 2018 Abstract: A key question in the formation of the relativistic jets in active galactic nuclei (AGNs) is the collimation process of their energetic plasma flow launched from the central supermassive black hole (SMBH). Recent observations of nearby low-luminosity radio galaxies exhibit a clear picture of parabolic collimation inside the Bondi accretion radius. On the other hand, little is known of the observational properties of jet collimation in more luminous quasars, where the accretion flow may be significantly different due to much higher accretion rates. In this paper, we present preliminary results of multi-frequency observations of the archetypal quasar 3C 273 with the Very Long Baseline Array (VLBA) at 1.4, 15, and 43 GHz, and Multi-Element Radio Linked Interferometer Network (MERLIN) at 1.6 GHz. -
Star Maps: Where Are the Black Holes?
BLACK HOLE FAQ’s 1. What is a black hole? A black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull. There are three kinds of black hole that we have strong evidence for: a. Stellar-mass black holes are the remaining cores of massive stars after they die in a supernova explosion. b. Mid-mass black hole in the centers of dense star clusters Credit : ESA, NASA, and F. Mirabel c. Supermassive black hole are found in the centers of many (and maybe all) galaxies. 2. Can a black hole appear anywhere? No, you need an amount of matter more than 3 times the mass of the Sun before it can collapse to create a black hole. 3. If a star dies, does it always turn into a black hole? No, smaller stars like our Sun end their lives as dense hot stars called white dwarfs. Much more massive stars end their lives in a supernova explosion. The remaining cores of only the most massive stars will form black holes. 4. Will black holes suck up all the matter in the universe? No. A black hole has a very small region around it from which you can't escape, called the “event horizon”. If you (or other matter) cross the horizon, you will be pulled in. But as long as you stay outside of the horizon, you can avoid getting pulled in if you are orbiting fast enough. 5. What happens when a spaceship you are riding in falls into a black hole? Your spaceship, along with you, would be squeezed and stretched until it was torn completely apart as it approached the center of the black hole. -
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. -
The Large Scale Universe As a Quasi Quantum White Hole
International Astronomy and Astrophysics Research Journal 3(1): 22-42, 2021; Article no.IAARJ.66092 The Large Scale Universe as a Quasi Quantum White Hole U. V. S. Seshavatharam1*, Eugene Terry Tatum2 and S. Lakshminarayana3 1Honorary Faculty, I-SERVE, Survey no-42, Hitech city, Hyderabad-84,Telangana, India. 2760 Campbell Ln. Ste 106 #161, Bowling Green, KY, USA. 3Department of Nuclear Physics, Andhra University, Visakhapatnam-03, AP, India. Authors’ contributions This work was carried out in collaboration among all authors. Author UVSS designed the study, performed the statistical analysis, wrote the protocol, and wrote the first draft of the manuscript. Authors ETT and SL managed the analyses of the study. All authors read and approved the final manuscript. Article Information Editor(s): (1) Dr. David Garrison, University of Houston-Clear Lake, USA. (2) Professor. Hadia Hassan Selim, National Research Institute of Astronomy and Geophysics, Egypt. Reviewers: (1) Abhishek Kumar Singh, Magadh University, India. (2) Mohsen Lutephy, Azad Islamic university (IAU), Iran. (3) Sie Long Kek, Universiti Tun Hussein Onn Malaysia, Malaysia. (4) N.V.Krishna Prasad, GITAM University, India. (5) Maryam Roushan, University of Mazandaran, Iran. Complete Peer review History: http://www.sdiarticle4.com/review-history/66092 Received 17 January 2021 Original Research Article Accepted 23 March 2021 Published 01 April 2021 ABSTRACT We emphasize the point that, standard model of cosmology is basically a model of classical general relativity and it seems inevitable to have a revision with reference to quantum model of cosmology. Utmost important point to be noted is that, ‘Spin’ is a basic property of quantum mechanics and ‘rotation’ is a very common experience. -
Modeling and Interpretation of the Ultraviolet Spectral Energy Distributions of Primeval Galaxies
Ecole´ Doctorale d'Astronomie et Astrophysique d'^Ile-de-France UNIVERSITE´ PARIS VI - PIERRE & MARIE CURIE DOCTORATE THESIS to obtain the title of Doctor of the University of Pierre & Marie Curie in Astrophysics Presented by Alba Vidal Garc´ıa Modeling and interpretation of the ultraviolet spectral energy distributions of primeval galaxies Thesis Advisor: St´ephane Charlot prepared at Institut d'Astrophysique de Paris, CNRS (UMR 7095), Universit´ePierre & Marie Curie (Paris VI) with financial support from the European Research Council grant `ERC NEOGAL' Composition of the jury Reviewers: Alessandro Bressan - SISSA, Trieste, Italy Rosa Gonzalez´ Delgado - IAA (CSIC), Granada, Spain Advisor: St´ephane Charlot - IAP, Paris, France President: Patrick Boisse´ - IAP, Paris, France Examinators: Jeremy Blaizot - CRAL, Observatoire de Lyon, France Vianney Lebouteiller - CEA, Saclay, France Dedicatoria v Contents Abstract vii R´esum´e ix 1 Introduction 3 1.1 Historical context . .4 1.2 Early epochs of the Universe . .5 1.3 Galaxytypes ......................................6 1.4 Components of a Galaxy . .8 1.4.1 Classification of stars . .9 1.4.2 The ISM: components and phases . .9 1.4.3 Physical processes in the ISM . 12 1.5 Chemical content of a galaxy . 17 1.6 Galaxy spectral energy distributions . 17 1.7 Future observing facilities . 19 1.8 Outline ......................................... 20 2 Modeling spectral energy distributions of galaxies 23 2.1 Stellar emission . 24 2.1.1 Stellar population synthesis codes . 24 2.1.2 Evolutionary tracks . 25 2.1.3 IMF . 29 2.1.4 Stellar spectral libraries . 30 2.2 Absorption and emission in the ISM . 31 2.2.1 Photoionization code: CLOUDY ....................... -
Virgo the Virgin
Virgo the Virgin Virgo is one of the constellations of the zodiac, the group tion Virgo itself. There is also the connection here with of 12 constellations that lies on the ecliptic plane defined “The Scales of Justice” and the sign Libra which lies next by the planets orbital orientation around the Sun. Virgo is to Virgo in the Zodiac. The study of astronomy had a one of the original 48 constellations charted by Ptolemy. practical “time keeping” aspect in the cultures of ancient It is the largest constellation of the Zodiac and the sec- history and as the stars of Virgo appeared before sunrise ond - largest constellation after Hydra. Virgo is bordered by late in the northern summer, many cultures linked this the constellations of Bootes, Coma Berenices, Leo, Crater, asterism with crops, harvest and fecundity. Corvus, Hydra, Libra and Serpens Caput. The constella- tion of Virgo is highly populated with galaxies and there Virgo is usually depicted with angel - like wings, with an are several galaxy clusters located within its boundaries, ear of wheat in her left hand, marked by the bright star each of which is home to hundreds or even thousands of Spica, which is Latin for “ear of grain”, and a tall blade of galaxies. The accepted abbreviation when enumerating grass, or a palm frond, in her right hand. Spica will be objects within the constellation is Vir, the genitive form is important for us in navigating Virgo in the modern night Virginis and meteor showers that appear to originate from sky. Spica was most likely the star that helped the Greek Virgo are called Virginids. -
2) Adolgov-PACTS.Pdf
Primordial black holes, dark matter, and other cosmological puzzles A. D. Dolgov Novosibirsk State University, Novosibirsk, Russia ITEP, Moscow, Russia Particle, Astroparticle, and Cosmology Tallinn Symposium Tallinn, Estonia, June 18-22 2018 A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 1 / 39 Recent astronomical data, which keep on appearing almost every day, show that the contemporary, z ∼ 0, and early, z ∼ 10, universe is much more abundantly populated by all kind of black holes, than it was expected even a few years ago. They may make a considerable or even 100% contribution to the cosmological dark matter. Among these BH: massive, M ∼ (7 − 8)M , 6 9 supermassive, M ∼ (10 − 10 )M , 3 5 intermediate mass M ∼ (10 − 10 )M , and a lot between and out of the intervals. Most natural is to assume that these black holes are primordial, PBH. Existence of such primordial black holes was essentially predicted a quarter of century ago (A.D. and J.Silk, 1993). A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 2 / 39 However, this interpretation encounters natural resistance from the astronomical establishment. Sometimes the authors of new discoveries admitted that the observed phenomenon can be the explained by massive BHs, which drove the effect, but immediately retreated, saying that there was no known way to create sufficiently large density of such BHs. A. D. Dolgov PBH, DM, and other cosmological puzzles 19 June 2018 3 / 39 Astrophysical BH versus PBH Astrophysical BHs are results of stellar collapce after a star exhausted its nuclear fuel. -
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. -
12 Strong Gravitational Lenses
12 Strong Gravitational Lenses Phil Marshall, MaruˇsaBradaˇc,George Chartas, Gregory Dobler, Ard´ısEl´ıasd´ottir,´ Emilio Falco, Chris Fassnacht, James Jee, Charles Keeton, Masamune Oguri, Anthony Tyson LSST will contain more strong gravitational lensing events than any other survey preceding it, and will monitor them all at a cadence of a few days to a few weeks. Concurrent space-based optical or perhaps ground-based surveys may provide higher resolution imaging: the biggest advances in strong lensing science made with LSST will be in those areas that benefit most from the large volume and the high accuracy, multi-filter time series. In this chapter we propose an array of science projects that fit this bill. We first provide a brief introduction to the basic physics of gravitational lensing, focusing on the formation of multiple images: the strong lensing regime. Further description of lensing phenomena will be provided as they arise throughout the chapter. We then make some predictions for the properties of samples of lenses of various kinds we can expect to discover with LSST: their numbers and distributions in redshift, image separation, and so on. This is important, since the principal step forward provided by LSST will be one of lens sample size, and the extent to which new lensing science projects will be enabled depends very much on the samples generated. From § 12.3 onwards we introduce the proposed LSST science projects. This is by no means an exhaustive list, but should serve as a good starting point for investigators looking to exploit the strong lensing phenomenon with LSST. -
The Hubble Space Telescope: 21 Years and Counting
Mem. S.A.It. Vol. 83, 393 c SAIt 2012 Memorie della The Hubble Space Telescope: 21 years and counting N. Panagia1;2;3 1 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA 2 Istituto Nazionale di Astrofisica – Osservatorio Astrofisico di Catania, Via S. Sofia 78, I-95123 Catania, Italy 3 Supernova Ltd, OYV #131, Northsound Road, Virgin Gorda, British Virgin Islands e-mail: [email protected] Abstract. I summarize the current status of the Hubble Space Telescope (HST) and illus- trate some of its exciting results. Key words. Telescopes: HST – Cosmology: observations – Dark Matter – Early Universe – Galaxies: Magellanic Clouds – Stellar Populations – Stars: V838 Mon – Planetary System – Comet: SL9 – Planets and Satellites: Pluto 1. Introduction After SM3B, HST’s science instruments in- cluded a spectrograph, the Space Telescope After twenty one years in orbit, the now “adult” Imaging Spectrograph (STIS) operating in the Hubble Space Telescope (HST) continues to UV and optical domains, and three cam- play a major role in astronomical research, and eras, the Wide Field - Planetary Camera 2 is undoubtedly one of the most important and (WFPC2), the Advanced Camera for Surveys most prolific space astronomy missions of all (ACS), the Near Infrared Camera - Multiobject time. Spectrograph (NICMOS), which was revived HST was deployed in low-Earth orbit in mission 3B with the installation of a (about 600 km) by the crew of the space mechanical cooling system, and the Fine shuttle Discovery (STS-31) on 25 April 1990. Guidance Sensors (FGS, primarily used for as- Although at the beginning the mission looked trometric observations). -
Monthly Newsletter of the Durban Centre - March 2018
Page 1 Monthly Newsletter of the Durban Centre - March 2018 Page 2 Table of Contents Chairman’s Chatter …...…………………….……….………..….…… 3 Andrew Gray …………………………………………...………………. 5 The Hyades Star Cluster …...………………………….…….……….. 6 At the Eye Piece …………………………………………….….…….... 9 The Cover Image - Antennae Nebula …….……………………….. 11 Galaxy - Part 2 ….………………………………..………………….... 13 Self-Taught Astronomer …………………………………..………… 21 The Month Ahead …..…………………...….…….……………..…… 24 Minutes of the Previous Meeting …………………………….……. 25 Public Viewing Roster …………………………….……….…..……. 26 Pre-loved Telescope Equipment …………………………...……… 28 ASSA Symposium 2018 ………………………...……….…......…… 29 Member Submissions Disclaimer: The views expressed in ‘nDaba are solely those of the writer and are not necessarily the views of the Durban Centre, nor the Editor. All images and content is the work of the respective copyright owner Page 3 Chairman’s Chatter By Mike Hadlow Dear Members, The third month of the year is upon us and already the viewing conditions have been more favourable over the last few nights. Let’s hope it continues and we have clear skies and good viewing for the next five or six months. Our February meeting was well attended, with our main speaker being Dr Matt Hilton from the Astrophysics and Cosmology Research Unit at UKZN who gave us an excellent presentation on gravity waves. We really have to be thankful to Dr Hilton from ACRU UKZN for giving us his time to give us presentations and hope that we can maintain our relationship with ACRU and that we can draw other speakers from his colleagues and other research students! Thanks must also go to Debbie Abel and Piet Strauss for their monthly presentations on NASA and the sky for the following month, respectively.