The Start of the Sagittarius Spiral
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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◦. -
Eclipse Newsletter
ECLIPSE NEWSLETTER The Eclipse Newsletter is dedicated to increasing the knowledge of Astronomy, Astrophysics, Cosmology and related subjects. VOLUMN 2 NUMBER 1 JANUARY – FEBRUARY 2018 PLEASE SEND ALL PHOTOS, QUESTIONS AND REQUST FOR ARTICLES TO [email protected] 1 MCAO PUBLIC NIGHTS AND FAMILY NIGHTS. The general public and MCAO members are invited to visit the Observatory on select Monday evenings at 8PM for Public Night programs. These programs include discussions and illustrated talks on astronomy, planetarium programs and offer the opportunity to view the planets, moon and other objects through the telescope, weather permitting. Due to limited parking and seating at the observatory, admission is by reservation only. Public Night attendance is limited to adults and students 5th grade and above. If you are interested in making reservations for a public night, you can contact us by calling 302-654- 6407 between the hours of 9 am and 1 pm Monday through Friday. Or you can email us any time at [email protected] or [email protected]. The public nights will be presented even if the weather does not permit observation through the telescope. The admission fees are $3 for adults and $2 for children. There is no admission cost for MCAO members, but reservations are still required. If you are interested in becoming a MCAO member, please see the link for membership. We also offer family memberships. Family Nights are scheduled from late spring to early fall on Friday nights at 8:30PM. These programs are opportunities for families with younger children to see and learn about astronomy by looking at and enjoying the sky and its wonders. -
SEDIGISM-ATLASGAL: Dense Gas Fraction and Star Formation Efficiency Across the Galactic Disk
MNRAS 000,1– ?? (2020) Preprint 4 December 2020 Compiled using MNRAS LATEX style file v3.0 SEDIGISM-ATLASGAL: Dense Gas Fraction and Star Formation Efficiency Across the Galactic Disk?† J. S. Urquhart1‡, C. Figura2, J. R. Cross1, M. R. A. Wells1, T. J. T. Moore3, D. J. Eden3, S. E. Ragan4, A. R. Pettitt5, A. Duarte-Cabral4, D. Colombo6, F. Schuller7;6, T. Csengeri8, M. Mattern9;6, H. Beuther10, K. M. Menten6, F. Wyrowski6, L. D. Anderson11;12;13, P.J. Barnes14, M. T. Beltrán15, S. J. Billington1, L. Bronfman16, A. Giannetti17, J. Kainulainen18, J. Kauffmann19 , M.-Y.Lee20, S. Leurini21, S.-N. X. Medina6, F. M. Montenegro22, M. Riener10, A. J. Rigby4, A. Sánchez-Monge23, P.Schilke23, E. Schisano24, A. Traficante24, M. Wienen25 Affiliations can be found after the references. Accepted XXX. Received YYY; in original form ZZZ ABSTRACT By combining two surveys covering a large fraction of the molecular material in the Galactic disk we investigate the role the spiral arms play in the star formation process. We have matched clumps identified by ATLASGAL with their parental GMCs as identified by SEDIGISM, and use these giant molecular cloud (GMC) masses, the bolometric luminosi- ties, and integrated clump masses obtained in a concurrent paper to estimate the dense gas fractions (DGFgmc = ∑Mclump=Mgmc) and the instantaneous star forming efficiencies (i.e., SFEgmc = ∑Lclump=Mgmc). We find that the molecular material associated with ATLASGAL clumps is concentrated in the spiral arms (∼60 per cent found within ±10 km s−1 of an arm). We have searched for variations in the values of these physical parameters with respect to their proximity to the spiral arms, but find no evidence for any enhancement that might be attributable to the spiral arms. -
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. -
The Kinematics of Warm Ionized Gas in the Fourth Galactic Quadrant Martin C
The Kinematics of Warm Ionized Gas in the Fourth Galactic Quadrant Martin C. Gostisha, Robert A. Benjamin (University of Wisconsin-Whitewater), L.M. Haffner (University of Wisconsin- Madison), Alex Hill (CSIRO), and Kat Barger (University of Notre Dame) Abstract: We present an preliminary analysis oF an on-going Wisconsin H-Alpha Mapper (WHAM) survey oF the Fourth quadrant oF the Galac>c plane in diffuse emission From [S II] 6716 A, covering the Fourth galac>c quadrant (Galac>c longitude = 270-360 degrees) and Galac>c latude |b| < 12 degrees. Because oF the high atomic mass and narrow thermal line widths oF sulFur (as compared to hydrogen or nitrogen, this emission line serves as the best tracer oF the kinemacs oF the warm ionized medium in the mid plane oF the Galaxy. We detect extensive emission at veloci>es as negave as -100 km/s indicang that we are seeing much Further into the center oF the Milky Way than was Found For the first quadrant. We discuss constraints on the velocity and ver>cal density structure oF this gas, and compare this distribu>on with what is observed in CO and HI surveys. This work was par>ally supported by the Naonal Science Foundaon’s REU program through NSF award AST-1004881. [SII] provides beNer velocity resolu3on than H-Alpha V The equaon, __________ LSR 40 30 30 gives us a physical value For the line widths oF both H-Alpha and [SII], varying only by the mass oF the individual atoms. Assuming that the gas is at a temperature oF 4 10 T=10 K, the velocity widths oF H-Alpha and [SII], respec>vely, are 20 0 km s-1 10 -10 Figure 2. -
Arxiv:1907.03763V1 [Astro-Ph.GA] 8 Jul 2019 Keywords: Galaxy: Disk — Galaxy: Kinematics and Dynamics — Galaxy: Solar Neighborhood — Galaxy: Structure
Draft version July 10, 2019 Typeset using LATEX twocolumn style in AASTeX62 Stellar Overdensity in the Local Arm in Gaia DR2 Yusuke Miyachi,1 Nobuyuki Sakai,2, 3 Daisuke Kawata,4 Junichi Baba,5 Mareki Honma,2, 6, 7 Noriyuki Matsunaga,8 and Kenta Fujisawa1 1Department of Physics, Faculty of Science, Yamaguchi University, Yoshida 1677-1, Yamaguchi-city, Yamaguchi 753-8512, Japan 2Mizusawa VLBI observatory, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 3Korea Astronomy & Space Science Institute, 776, Daedeokdae-ro, Yuseong-gu, Daejeon 34055, Korea 4Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK 5National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 6Mizusawa VLBI observatory, National Astronomical Observatory of Japan, 2-12 Hoshi-ga-oka-cho, Mizusawa-ku, Oshu, Iwate 023-0861, Japan 7The Graduate University for Advanced Studies (Sokendai), Mitaka, Tokyo 181-8588, Japan 8Department of Astronomy, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan (Received March 31, 2019; Revised June 17, 2019; Accepted July 2, 2019) Submitted to ApJ ABSTRACT Using the cross-matched data of Gaia DR2 and 2MASS Point Source Catalog, we investigated the surface density distribution of stars aged 1 Gyr in the thin disk in the range of 90◦ l 270◦. We ∼ ≤ ≤ selected 4,654 stars above the turnoff corresponding to the age 1 Gyr, that fall within a small box ∼ region in the color{magnitude diagram, (J K ) versus M(K ), for which the distance and reddening − s 0 s are corrected. -
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 -
29 Jan 2020 11Department of Physics, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-Ku, Sapporo, Hokkaido 060-0810, Japan
Publ. Astron. Soc. Japan (2014) 00(0), 1–42 1 doi: 10.1093/pasj/xxx000 FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45 m telescope (FUGIN). VI. Dense gas and mini-starbursts in the W43 giant molecular cloud complex Mikito KOHNO1∗, Kengo TACHIHARA1∗, Kazufumi TORII2∗, Shinji FUJITA1∗, Atsushi NISHIMURA1,3, Nario KUNO4,5, Tomofumi UMEMOTO2,6, Tetsuhiro MINAMIDANI2,6,7, Mitsuhiro MATSUO2, Ryosuke KIRIDOSHI3, Kazuki TOKUDA3,7, Misaki HANAOKA1, Yuya TSUDA8, Mika KURIKI4, Akio OHAMA1, Hidetoshi SANO1,9, Tetsuo HASEGAWA7, Yoshiaki SOFUE10, Asao HABE11, Toshikazu ONISHI3 and Yasuo FUKUI1,9 1Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan 2Nobeyama Radio Observatory, National Astronomical Observatory of Japan (NAOJ), National Institutes of Natural Sciences (NINS), 462-2, Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305, Japan 3Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan 4Department of Physics, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305-8577, Japan 5Tomonaga Center for the History of the Universe, University of Tsukuba, Ten-nodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan 6Department of Astronomical Science, School of Physical Science, SOKENDAI (The Graduate University for Advanced Studies), 2-21-1, Osawa, Mitaka, Tokyo 181-8588, Japan 7National Astronomical Observatory of Japan (NAOJ), National -
The Milky Way
Astronomy Cast Episode 99: The Milky Way Fraser Cain: Ninety-nine episodes Pamela! Dr. Pamela Gay: I know [Laughter] it’s amazing how far and how long we’ve been doing this. Fraser: The Milky Way is our home galaxy but we’ve only understood its true nature for about a century. We share this beautiful barred spiral galaxy with at least 200 billion other stars. Let’s trace back the history, see how we learned about the Milky Way and then compare it to other galaxies out there. What does the future hold for the Milky Way? Pamela: The future holds death, because that’s kinda what happens in the Universe. [Laughter] Fraser: Shhh….we’re supposed to keep that as a surprise! It all ends in tears. But, let’s go back to the beginning. [Laughter] I find that kinda interesting. My dad had an antique book about Astronomy. It had all the constellations and stuff. It was back from like the 1920s or earlier. It had nebula for the Andromeda nebula and other stuff. Let’s go back like as far as we can and talk a bit about the history of the Milky Way. You could see the Milky Way in the night sky so people knew that there was something there. What did they think was going on? Pamela: Well the term Milky Way is actually derived from a Latin term. We’ve had that name for it for a long time. It basically comes from the fact that there is this band of light that to the naked eye is perceived as this light patch, this illuminated patch that spreads in an arc across the sky. -
University of Maryland Department of Physics and Astronomy
PROPAGATION OF COSMIC RAYS IN THE GALAXY R. R. Daniel Tata Institute of Fundamental Research Homi Bhabha Road, Bombay, India and S. A. Stephens* Department of Physics & Astronomy, University of Maryland and Goddard Space Flight Center, Greenbelt, Maryland, U.S.A. Technical Report No. 75-028 UNIVERSITY OF MARYLAND DEPARTMENT OF PHYSICS AND ASTRONOMY COLLEGE PARK, MARYLAND (NASA-CR-141190) PROPAGATION OF COSMIC RAYS N75-15580 IN THE GALAXY (Maryland Univ.) 208 p HC $7.25 CSCL 03B Unclas G3/93 05074 This is a preprint of research carried out at the University of Maryland. In order to promote the active exchange of research results, individuals and groups at your institution are encouraged to send their preprints to PREPRINT LIBRARY DEPARTMENT 'OF PHYSICS AND ASTRONOMY UNIVERSITY OF MARYLAND COLLEGE PARK, MARYLAND 20742 U.S.A. PROPAGATION OF COSMIC RAYS IN THE GALAXY R. R. Daniel Tata Institute of Fundamental Research Homi Bhabha Road, Bombay, India and S. A. Stephens* Department of Physics & Astronomy, University of Maryland and Goddard Space Flight Center, Greenbelt, Maryland, U.S.A. Technical Report No. 75-028 To appear in Space Science Reviews *on leave from Tata Institute of Fundamental Research, Bombay, India. CONTENTS 1. Introduction 1.1. Models of cosmic ray confinement 1.2. The galactic model for cosmic ray confinement 1.3. Scope of the present review 2. General description of the Galaxy 2.1. Dimensions and density 2.2. Structure 2.3. Interstellar gas 2.4. Magnetic fields 2.5. Radiation fields 3. Cosmic ray propagation in the Galaxy: Theoretical aspects 3.1. -
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.