The Gould Belt
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Constructing a Galactic Coordinate System Based on Near-Infrared and Radio Catalogs
A&A 536, A102 (2011) Astronomy DOI: 10.1051/0004-6361/201116947 & c ESO 2011 Astrophysics Constructing a Galactic coordinate system based on near-infrared and radio catalogs J.-C. Liu1,2,Z.Zhu1,2, and B. Hu3,4 1 Department of astronomy, Nanjing University, Nanjing 210093, PR China e-mail: [jcliu;zhuzi]@nju.edu.cn 2 key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education, Nanjing 210093, PR China 3 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, PR China 4 Graduate School of Chinese Academy of Sciences, Beijing 100049, PR China e-mail: [email protected] Received 24 March 2011 / Accepted 13 October 2011 ABSTRACT Context. The definition of the Galactic coordinate system was announced by the IAU Sub-Commission 33b on behalf of the IAU in 1958. An unrigorous transformation was adopted by the Hipparcos group to transform the Galactic coordinate system from the FK4-based B1950.0 system to the FK5-based J2000.0 system or to the International Celestial Reference System (ICRS). For more than 50 years, the definition of the Galactic coordinate system has remained unchanged from this IAU1958 version. On the basis of deep and all-sky catalogs, the position of the Galactic plane can be revised and updated definitions of the Galactic coordinate systems can be proposed. Aims. We re-determine the position of the Galactic plane based on modern large catalogs, such as the Two-Micron All-Sky Survey (2MASS) and the SPECFIND v2.0. This paper also aims to propose a possible definition of the optimal Galactic coordinate system by adopting the ICRS position of the Sgr A* at the Galactic center. -
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. -
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: -
Formation and Evolution of Galaxies and Black Holes
Journal of Physical Science and Application 8 (1) (2018) 23-29 doi: 10.17265/2159-5348/2018.01.003 D DAVID PUBLISHING Formation and Evolution of Galaxies and Black Holes Cui-xiang Zhong Department of Science and Technology, Jiangxi Normal University, Nanchang 330022, China Abstract: In the past, people did not realize the formation and structure of galaxies. They even mistook the black holes hidden in the center of a galaxy as independent celestial objects, making black holes mysterious and unbelievable. It was only after the author studied and discovered the laws of the formation and evolution of satellites, planets and stars that he put forward the scientific theory of galaxy formation and evolution, therefore revealing the hierarchical structure of galaxy and the existence and characteristics of black holes as the main nodes of galactic structure. Key words: Galactic structure, galaxy formation, galaxy evolution, black holes, black hole area. 1. Introduction achievements in the research field of black holes. In 2005, the working group led by Zhiqiang Shen of As early as 1930s, it has been recognized that Shanghai Astronomical Observatory of Chinese galaxies in the universe are not randomly distributed, Academy of Sciences found some conclusive evidence but because of the lack of two dimensional supporting that there exists a super massive black observational data, there has been no breakthrough in holes in the center of Milky Way. In 2015, the the understanding of large-scale structures. Only until international team led by astronomers from Peking 1980s, with the continuous deepening of red-shift University in China and from the University of survey, could one clearly describe the Arizona announces their findings of a quasar, with its three-dimensional distribution of galaxies in large central black hole mass of 12 billion solar masses and scale structure, and found that galaxies have lumpy the luminosity of 420 trillion suns is at a distance of structures. -
Radio Astronomers Peer Deep Into the Stellar Nursery of the Orion Nebula 15 June 2017
Radio astronomers peer deep into the stellar nursery of the Orion Nebula 15 June 2017 stars," says Rachel Friesen, one of the collaboration's co-Principal Investigators and, until 31 May 2017, a Dunlap Fellow at the Dunlap Institute for Astronomy & Astrophysics, University of Toronto. "But ammonia is an excellent tracer of dense, star- forming gas," says Friesen, "and these large ammonia maps will allow us to track the motions and temperature of the densest gas. This is critical to assessing whether gas clouds and filaments are stable, or are undergoing collapse on their way to forming new stars." The image accompanies the first release of results from the collaboration's Green Bank Ammonia Survey (GAS), published in the Astrophysical Journal. The collaboration's other co-Principal Investigator is Jaime Pineda, from the Max Planck Institute for Extraterrestrial Physics; the team also includes astronomers from the University of In this composite image combining GBT radio and WISE Toronto's Department of Astronomy & Astrophysics infrared observations, the filament of ammonia and Canadian Institute for Theoretical Astrophysics. molecules appears red and Orion Nebula gas appears blue. Credit: R. Friesen, Dunlap Institute; J. Pineda, The goal of GAS is to survey all the major, nearby MPIP; GBO/AUI/NSF star-forming regions in the northern half of the Gould Belt—a ring of young stars and gas clouds that circles the entire sky and runs through the Astronomers have released an image of a vast constellation Orion. The survey will eventually filament of star-forming gas, 1200 light-years away, provide a clearer picture over a larger portion of the in the stellar nursery of the Orion Nebula. -
Life Cycle of Stars Script Edited by SJ on 29Th June 2011
Life Cycle of Stars Script Edited by SJ on 29th June 2011. This first show is based loosely on the Life Cycle of Stars. It is aimed at students studying GCSE Astronomy. If the kids are younger than GCSE or below, nicer to start with Planets and Ecliptic and star signs stuff, detailed in Optional Start, leaving out more complex stuff on Neutron Stars and Black Holes. Stellarium commands are in blue Red notes are optional facts to add, and depend on age of audience and time. The talk should take 20-30 mins depending on how much science/mythology you elaborate on. Suggest that it is nice to do this show condensed into 20 mins at the end of We are Astronomers… to give a 40-45minute show. Optional easing-in start Do this if audience have no real knowledge of the stars and planets - best starting point for younger kids, if GCSE probably not needed can jump straight in at Finding North, but check! In stellarium start with sky as it is with sun (a for atmosphere) and ground, g. and at current time 8 . Ask ‘Can we see any stars in the night sky?’ Expect responses such as ‘Only the Sun, no because it’s too bright’- Ask ‘so why can’t we see the other stars in the day?’ - Get response cos our star the sun, too bright, light bounces off atmosphere, stops us seeing the other stars. Mention the light pollution in cities bouncing off the inner atmosphere stopping us seeing stars even at Night! Speed up time <L> and see sun moving across the sky, ask why the sun is moving? Explain that sun is not actually moving it’s us that is moving about on our axis and this makes the sun appear to rise in the East and set in the West. -
The System of Molecular Clouds in the Gould Belt in Details
Astronomy Letters, 2016, Vol. 42, No. 8, pp. 544–554. The System of Molecular Clouds in the Gould Belt V.V. Bobylev Pulkovo Astronomical Observatory, St. Petersburg, Russia Abstract—Based on high-latitude molecular clouds with highly accurate distance estimates taken from the literature, we have redetermined the parameters of their spatial orientation. This system can be approximated by a 350 235 140 pc ellipsoid inclined by the angle i = 17 2◦ to the Galactic plane with× the longitude× of the ascending ◦ ± node lΩ = 337 1 . Based on the radial velocities of the clouds, we have found their ± group velocity relative to the Sun to be (u0, v0,w0) = (10.6, 18.2, 6.8) (0.9, 1.7, 1.5) km s−1. The trajectory of the center of the molecular cloud system in± the past in a time interval of 60 Myr has been constructed. Using data on masers associated with low- mass protostars,∼ we have calculated the space velocities of the molecular complexes in Orion, Taurus, Perseus, and Ophiuchus. Their motion in the past is shown to be not random. INTRODUCTION A giant stellar-gas complex known as the Gould Belt is located near the Sun (Frogel and Stothers 1977; Efremov 1989; P¨oppel 1997, 2001; Torra et al. 2000; Olano 2001). A giant cloud of neutral hydrogen called the Lindblad ring (Lindblad 1967, 2000) is associated with it; the system of nearby OB associations (de Zeeuw et al. 1999), open star clusters (Piskunov et al. 2006; Bobylev 2006), and complexes of nearby molecular clouds (Dame et al. -
Arxiv:1307.0569V1
IAUS 298 Setting the scence for Gaia and LAMOST Proceedings IAU Symposium No. 298, 2014 c 2014 International Astronomical Union S. Feltzing, G. Zhao, N. A. Walton & P. A. Whitelock, eds. DOI: 00.0000/X000000000000000X The Milky Way thin disk structure as revealed by stars and young open clusters Giovanni Carraro Alonso de Cordova 3107, 19001, Santiago de Chile, Chile email: [email protected] Abstract. In this contribution I shall focus on the structure of the Galactic thin disk. The evolution of the thin disk and its chemical properties have been discussed in detail by T. Bensby’s contribution in conjunction with the properties of the Galactic thick disk, and by L.Olivia in conjunction with the properties of the Galactic bulge. I will review and discuss the status of our understanding of three major topics, which have been the subject of intense research nowadays, after long years of silence: (1) the spiral structure of the Milky Way, (2) the size of the Galactic disk, and (3) the nature of the Local arm (Orion spur), where the Sun is immersed. The provisional conclusions of this discussion are that : (1) we still have quite a poor knowledge of the Milky Way spiral structure, and the main dis-agreements among various tracers are still to be settled; (2) the Galactic disk does clearly not have an obvious luminous cut-off at about 14 kpc from the Galactic center, and next generation Galactic models need to be updated in this respect, and (3) the Local arm is most probably an inter-arm structure, similar to what we see in several external spirals, like M 74. -
Astrophysics in 2006 3
ASTROPHYSICS IN 2006 Virginia Trimble1, Markus J. Aschwanden2, and Carl J. Hansen3 1 Department of Physics and Astronomy, University of California, Irvine, CA 92697-4575, Las Cumbres Observatory, Santa Barbara, CA: ([email protected]) 2 Lockheed Martin Advanced Technology Center, Solar and Astrophysics Laboratory, Organization ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304: ([email protected]) 3 JILA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder CO 80309: ([email protected]) Received ... : accepted ... Abstract. The fastest pulsar and the slowest nova; the oldest galaxies and the youngest stars; the weirdest life forms and the commonest dwarfs; the highest energy particles and the lowest energy photons. These were some of the extremes of Astrophysics 2006. We attempt also to bring you updates on things of which there is currently only one (habitable planets, the Sun, and the universe) and others of which there are always many, like meteors and molecules, black holes and binaries. Keywords: cosmology: general, galaxies: general, ISM: general, stars: general, Sun: gen- eral, planets and satellites: general, astrobiology CONTENTS 1. Introduction 6 1.1 Up 6 1.2 Down 9 1.3 Around 10 2. Solar Physics 12 2.1 The solar interior 12 2.1.1 From neutrinos to neutralinos 12 2.1.2 Global helioseismology 12 2.1.3 Local helioseismology 12 2.1.4 Tachocline structure 13 arXiv:0705.1730v1 [astro-ph] 11 May 2007 2.1.5 Dynamo models 14 2.2 Photosphere 15 2.2.1 Solar radius and rotation 15 2.2.2 Distribution of magnetic fields 15 2.2.3 Magnetic flux emergence rate 15 2.2.4 Photospheric motion of magnetic fields 16 2.2.5 Faculae production 16 2.2.6 The photospheric boundary of magnetic fields 17 2.2.7 Flare prediction from photospheric fields 17 c 2008 Springer Science + Business Media. -
Astronomy Alphabet
Astronomy Alphabet Educational video for children Teacher https://vimeo.com/77309599 & Learner Guide This guide gives background information about the astronomy topics mentioned in the video, provides questions and answers children may be curious about, and suggests topics for discussion. Alhazen A Alhazen, called the Father of Optics, performed NASA/Goddard/Lunar Reconnaissance Orbiter, Apollo 17 experiments over a thousand years ago Can you find Alhazen crater when you look at the Moon? to learn about how light travels and Why does the Moon look bigger near the behaves. He also studied astronomy, horizon? separated light into colors, and sought to Believe it or not, scientists still don’t know for sure why explain why the Moon looks bigger near we perceive the Moon to be larger when it lies near to the the horizon. horizon. Though photos of the Moon at different points in the sky show it to be the same size, we humans think we I’ve never heard of Abu Ali al-Hasan ibn al- see something quite different. Try this experiment yourself Hasan ibn al-Hatham (Alhazen). sometime! One possibility is that objects we see next to the Tell me more about him. Moon when it’s near to them give us the illusion that it’s We don’t know that much about Alhazen be- bigger, because of a sense of scale and reference. cause he lived so long ago, but we do know that he was born in Persia in 965. He wrote hundreds How many craters does the Moon have, and what of books on math and science and pioneered the are their names? scientific method of experimentation. -
Vol. 38, No. 3 September 2009 Journal of the International
Vol. 38, No. 3 September 2009 Journal of the International Planetarium Society Darkness at Dawn in India Page 18 September 2009 Vol. 38 No. 3 Executive Editor Articles Sharon Shanks Ward Beecher Planetarium 6 Greenwich’s Public Astronomer SteveTidey Youngstown State University 10 Russia’s Only High School Planetarium One University Plaza Dr. Larry Krumenaker Youngstown, Ohio 44555 USA 18 Darkness at Dawn in India Piyush Pandey +1 330-941-3619 20 IPS 2012: Baton Rouge Jon Elvert [email protected] 22 Eugenides Script Contest Revisions Advertising Coordinator Thomas Kraupe Dr. Dale Smith, Interim Coordinator (See Publications Committee on page 3) Columns Membership 63 25 Years Ago. Thomas Wm. Hamilton Individual: $50 one year; $90 two years 60 Book Reviews. April S. Whitt Institutional: $200 first year; $100 annual renewal 67 Calendar of Events. .Loris Ramponi Library Subscriptions: $36 one year 28 Educational Horizons . Jack L. Northrup Direct membership requests and changes of 30 General Counsel . Christopher S. Reed address to the Treasurer/Membership Chairman 32 IMERSA NEWS . .Judith Rubin 4 In Front of the Console . .Sharon Shanks Back Issues of the Planetarian 38 International News. Lars Broman IPS Back Publications Repository 68 Last Light . April S. Whitt maintained by the Treasurer/Membership Chair; 48 Mobile News. .Susan Reynolds Button contact information is on next page 51 NASA Space Science News. Anita Sohus 53 Past President’s Message . Susan Reynolds Button Index 56 Planetarium Show Reviews. Steve Case A cumulative index of major articles that have 24 President’s Message . Tom Mason appeared in the Planetarian from the first issue 64 What’s New. -
A First Look at the Auriga–California Giant Molecular Cloud with Herschel∗ and the Cso: Census of the Young Stellar Objects and the Dense Gas
The Astrophysical Journal,764:133(14pp),2013February20 doi:10.1088/0004-637X/764/2/133 C 2013. The American Astronomical Society. All rights reserved. Printed in the U.S.A. ! A FIRST LOOK AT THE AURIGA–CALIFORNIA GIANT MOLECULAR CLOUD WITH HERSCHEL∗ AND THE CSO: CENSUS OF THE YOUNG STELLAR OBJECTS AND THE DENSE GAS Paul M. Harvey1,CassandraFallscheer2,AdamGinsburg3,SusanTerebey4,PhilippeAndre´5,TylerL.Bourke6, James Di Francesco7,VeraKonyves¨ 5,8,BrendaC.Matthews7,andDawnE.Peterson9 1 Astronomy Department, University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259, USA; [email protected] 2 Department of Physics and Astronomy, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada; [email protected] 3 Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA; [email protected] 4 Department of Physics and Astronomy PS315, 5151 State University Drive, California State University at Los Angeles, Los Angeles, CA 90032, USA; [email protected] 5 Laboratoire AIM, CEA/DSM-CNRS-UniversiteParisDiderot,IRFU´ /Service d’Astrophysique, CEA Saclay, F-91191 Gif-sur-Yvette, France; [email protected], [email protected] 6 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA; [email protected] 7 Herzberg Institute of Astrophysics, National Research Council of Canada, 5071 West Saanich Road, Victoria, BC V9E 2E7, Canada; [email protected], [email protected] 8 Institut