GU Monocerotis: a High-Mass Eclipsing Overcontact Binary in the Young Open Cluster Dolidze 25? J
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Stsci Newsletter: 1997 Volume 014 Issue 01
January 1997 • Volume 14, Number 1 SPACE TELESCOPE SCIENCE INSTITUTE Highlights of this issue: • AURA science and functional awards to Leitherer and Hanisch — pages 1 and 23 • Cycle 7 to be extended — page 5 • Cycle 7 approved Newsletter program listing — pages 7-13 Astronomy with HST Climbing the Starburst Distance Ladder C. Leitherer Massive stars are an important and powerful star formation events in sometimes dominant energy source for galaxies. Even the most luminous star- a galaxy. Their high luminosity, both in forming regions in our Galaxy are tiny light and mechanical energy, makes on a cosmic scale. They are not them detectable up to cosmological dominated by the properties of an distances. Stars ~100 times more entire population but by individual massive than the Sun are one million stars. Therefore stochastic effects times more luminous. Except for stars prevail. Extinction represents a severe of transient brightness, like novae and problem when a reliable census of the supernovae, hot, massive stars are Galactic high-mass star-formation the most luminous stellar objects in history is atempted, especially since the universe. massive stars belong to the extreme Massive stars are, however, Population I, with correspondingly extremely rare: The number of stars small vertical scale heights. Moreover, formed per unit mass interval is the proximity of Galactic regions — roughly proportional to the -2.35 although advantageous for detailed power of mass. We expect to find very studies of individual stars — makes it few massive stars compared to, say, difficult to obtain integrated properties, solar-type stars. This is consistent with such as total emission-line fluxes of observations in our solar neighbor- the ionized gas. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Chapter 16 the Sun and Stars
Chapter 16 The Sun and Stars Stargazing is an awe-inspiring way to enjoy the night sky, but humans can learn only so much about stars from our position on Earth. The Hubble Space Telescope is a school-bus-size telescope that orbits Earth every 97 minutes at an altitude of 353 miles and a speed of about 17,500 miles per hour. The Hubble Space Telescope (HST) transmits images and data from space to computers on Earth. In fact, HST sends enough data back to Earth each week to fill 3,600 feet of books on a shelf. Scientists store the data on special disks. In January 2006, HST captured images of the Orion Nebula, a huge area where stars are being formed. HST’s detailed images revealed over 3,000 stars that were never seen before. Information from the Hubble will help scientists understand more about how stars form. In this chapter, you will learn all about the star of our solar system, the sun, and about the characteristics of other stars. 1. Why do stars shine? 2. What kinds of stars are there? 3. How are stars formed, and do any other stars have planets? 16.1 The Sun and the Stars What are stars? Where did they come from? How long do they last? During most of the star - an enormous hot ball of gas day, we see only one star, the sun, which is 150 million kilometers away. On a clear held together by gravity which night, about 6,000 stars can be seen without a telescope. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Uvsat: a Concept of an Ultraviolet/Optical Photometric Satellite
UVSat: a concept of an ultraviolet/optical photometric satellite A. Pigulski1, A. Baran2, M. Bzowski3, H. Cugier1, B. Czerny4, J. Daszy´nska-Daszkiewicz1, W. Dziembowski5·6, G. Handler5, Z. Ko laczkowski1, M. Kr´olikowska3, J. Krzesi´nski2, G. Maciejewski7, G. Michalska1, J. Molenda-Zakowicz_ 1, P. Moskalik5, A. Niedzielski7, E. Niemczura1, J. Ostrowski1, A. Pamyatnykh5, M. Ratajczak1, S. Rucinski8, M. Siwak2, R. Smolec5, S. Szutowicz3, T. Tomov7,L. Wyrzykowski6, S. Zo la9 and M. Sarna5 1. Instytut Astronomiczny, Uniwersytet Wroc lawski, Kopernika 11, 51-622 Wroc law, Poland 2. Instytut Fizyki Uniwersytetu Pedagogicznego, Podchora_zych, 2, 30-084 Krak´ow, Poland 3. Centrum Bada´nKosmicznych PAN, Bartycka 18a, 00-716 Warszawa, Poland 4. Centrum Fizyki Teoretycznej PAN, Al. Lotnik´ow 32/46, 02-668 Warszawa, Poland 5. Centrum Astronomiczne im. M. Kopernika PAN, Bartycka 18, 00-716 Warszawa, Poland 6. Obserwatorium Astronomiczne Uniwersytetu Warszawskiego, Al. Ujazdowskie 4, 00-478 Warszawa, Poland 7. Centrum Astronomii, Wydzia lFizyki, Astronomii i Informatyki Stosowanej, Uniwersytet Miko laja Kopernika, Grudziadzka, 5, 87-100 Toru´n, Poland 8. Department of Astronomy & Astrophysics, University of Toronto, 50 St. George Street, Toronto, Canada 9. Obserwatorium Astronomiczne Uniwersytetu Jagiello´nskiego, Orla 171, 30-244 Krak´ow, Poland Time-series photometry from space in the ultraviolet can be presently done with only a few platforms, none of which is able to provide wide-field long-term high- cadence photometry. We present a concept of UVSat, a twin space telescope which will be capable to perform this kind of photometry, filling an observational niche. The satellite will host two telescopes, one for observations in the ultravi- olet, the other for observations in the optical band. -
A New Universe to Discover: a Guide to Careers in Astronomy
A New Universe to Discover A Guide to Careers in Astronomy Published by The American Astronomical Society What are Astronomy and Astrophysics? Ever since Galileo first turned his new-fangled one-inch “spyglass” on the moon in 1609, the popular image of the astronomer has been someone who peers through a telescope at the night sky. But astronomers virtually never put eye to lens these days. The main source of astronomical data is still photons (particles of light) from space, but the tools used to gather and analyze them are now so sophisticated that it’s no longer necessary (or even possible, in most cases) for a human eye to look through them. But for all the high-tech gadgetry, the 21st-Century astronomer is still trying to answer the same fundamental questions that puzzled Galileo: How does the universe work, and where did it come from? Webster’s dictionary defines “astronomy” as “the science that deals with the material universe beyond the earth’s atmosphere.” This definition is broad enough to include great theoretical physicists like Isaac Newton, Albert Einstein, and Stephen Hawking as well as astronomers like Copernicus, Johanes Kepler, Fred Hoyle, Edwin Hubble, Carl Sagan, Vera Rubin, and Margaret Burbidge. In fact, the words “astronomy” and “astrophysics” are pretty much interchangeable these days. Whatever you call them, astronomers seek the answers to many fascinating and fundamental questions. Among them: *Is there life beyond earth? *How did the sun and the planets form? *How old are the stars? *What exactly are dark matter and dark energy? *How did the Universe begin, and how will it end? Astronomy is a physical (non-biological) science, like physics and chemistry. -
Arxiv:0908.2624V1 [Astro-Ph.SR] 18 Aug 2009
Astronomy & Astrophysics Review manuscript No. (will be inserted by the editor) Accurate masses and radii of normal stars: Modern results and applications G. Torres · J. Andersen · A. Gim´enez Received: date / Accepted: date Abstract This paper presents and discusses a critical compilation of accurate, fun- damental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and α Centauri) that satisfy our criterion that the mass and radius of both stars be known to ±3% or better. All are non-interacting systems, so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants. To these we add interstellar reddening, effective temperature, metal abundance, rotational velocity and apsidal motion determinations when available, and we compute a number of other physical parameters, notably luminosity and distance. These accurate physical parameters reveal the effects of stellar evolution with un- precedented clarity, and we discuss the use of the data in observational tests of stellar evolution models in some detail. Earlier findings of significant structural differences between moderately fast-rotating, mildly active stars and single stars, ascribed to the presence of strong magnetic and spot activity, are confirmed beyond doubt. We also show how the best data can be used to test prescriptions for the subtle interplay be- tween convection, diffusion, and other non-classical effects in stellar models. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
GEORGE HERBIG and Early Stellar Evolution
GEORGE HERBIG and Early Stellar Evolution Bo Reipurth Institute for Astronomy Special Publications No. 1 George Herbig in 1960 —————————————————————– GEORGE HERBIG and Early Stellar Evolution —————————————————————– Bo Reipurth Institute for Astronomy University of Hawaii at Manoa 640 North Aohoku Place Hilo, HI 96720 USA . Dedicated to Hannelore Herbig c 2016 by Bo Reipurth Version 1.0 – April 19, 2016 Cover Image: The HH 24 complex in the Lynds 1630 cloud in Orion was discov- ered by Herbig and Kuhi in 1963. This near-infrared HST image shows several collimated Herbig-Haro jets emanating from an embedded multiple system of T Tauri stars. Courtesy Space Telescope Science Institute. This book can be referenced as follows: Reipurth, B. 2016, http://ifa.hawaii.edu/SP1 i FOREWORD I first learned about George Herbig’s work when I was a teenager. I grew up in Denmark in the 1950s, a time when Europe was healing the wounds after the ravages of the Second World War. Already at the age of 7 I had fallen in love with astronomy, but information was very hard to come by in those days, so I scraped together what I could, mainly relying on the local library. At some point I was introduced to the magazine Sky and Telescope, and soon invested my pocket money in a subscription. Every month I would sit at our dining room table with a dictionary and work my way through the latest issue. In one issue I read about Herbig-Haro objects, and I was completely mesmerized that these objects could be signposts of the formation of stars, and I dreamt about some day being able to contribute to this field of study. -
Vente De 2 Ans Montés Samedi 14 Mai Breeze Le 13 Mai
11saint-cloud Vente de 2 ans montés Samedi 14 mai Breeze le 13 mai en association avec Index_Alpha_14_05 24/03/11 19:09 Page 71 Index alphabétique Alphabetical index NomsNOM des yearlings . .SUF . .Nos LOT NOM LOT ALKATARA . .0142 N(FAB'S MELODY 2009) . .0030 AMESBURY . .0148 N(FACTICE 2009) . .0031 FORCE MAJEUR . .0003 N(FAR DISTANCE 2009) . .0032 JOHN TUCKER . .0103 N(FIN 2009) . .0034 LIBERTY CAT . .0116 N(FLAMES 2009) . .0035 LUCAYAN . .0051 N(FOLLE LADY 2009) . .0036 MARCILHAC . .0074 N(FRANCAIS 2009) . .0037 MOST WANTED . .0123 N(GENDER DANCE 2009) . .0038 N(ABBEYLEIX LADY 2009) . .0139 N(GERMANCE 2009) . .0039 N(ABINGTON ANGEL 2009) . .0140 N(GILT LINKED 2009) . .0040 N(AIR BISCUIT 2009) . .0141 N(GREAT LADY SLEW 2009) . .0041 N(ALL EMBRACING 2009) . .0143 N(GRIN AND DARE IT 2009) . .0042 N(AMANDIAN 2009) . .0144 N(HARIYA 2009) . .0043 N(AMAZON BEAUTY 2009) . .0145 N(HOH MY DARLING 2009) . .0044 N(AMY G 2009) . .0146 N(INFINITY 2009) . .0045 N(ANSWER DO 2009) . .0147 N(INKLING 2009) . .0046 N(ARES VALLIS 2009) . .0149 N(JUST WOOD 2009) . .0048 N(AUCTION ROOM 2009) . .0150 N(KACSA 2009) . .0049 N(AVEZIA 2009) . .0151 N(KASSARIYA 2009) . .0050 N(BARCONEY 2009) . .0152 N(LALINA 2009) . .0052 N(BASHFUL 2009) . .0153 N(LANDELA 2009) . .0053 N(BAYOURIDA 2009) . .0154 N(LES ALIZES 2009) . .0054 N(BEE EATER 2009) . .0155 N(LIBRE 2009) . .0055 N(BELLA FIORELLA 2009) . .0156 N(LOUELLA 2009) . .0056 N(BERKELEY LODGE 2009) . .0157 N(LUANDA 2009) . .0057 N(BLACK PENNY 2009) . .0158 N(LUNA NEGRA 2009) . -
Astronomy 2009 Index
Astronomy Magazine 2009 Index Subject Index 1RXS J160929.1-210524 (star), 1:24 4C 60.07 (galaxy pair), 2:24 6dFGS (Six Degree Field Galaxy Survey), 8:18 21-centimeter (neutral hydrogen) tomography, 12:10 93 Minerva (asteroid), 12:18 2008 TC3 (asteroid), 1:24 2009 FH (asteroid), 7:19 A Abell 21 (Medusa Nebula), 3:70 Abell 1656 (Coma galaxy cluster), 3:8–9, 6:16 Allen Telescope Array (ATA) radio telescope, 12:10 ALMA (Atacama Large Millimeter/sub-millimeter Array), 4:21, 9:19 Alpha (α) Canis Majoris (Sirius) (star), 2:68, 10:77 Alpha (α) Orionis (star). See Betelgeuse (Alpha [α] Orionis) (star) Alpha Centauri (star), 2:78 amateur astronomy, 10:18, 11:48–53, 12:19, 56 Andromeda Galaxy (M31) merging with Milky Way, 3:51 midpoint between Milky Way Galaxy and, 1:62–63 ultraviolet images of, 12:22 Antarctic Neumayer Station III, 6:19 Anthe (moon of Saturn), 1:21 Aperture Spherical Telescope (FAST), 4:24 APEX (Atacama Pathfinder Experiment) radio telescope, 3:19 Apollo missions, 8:19 AR11005 (sunspot group), 11:79 Arches Cluster, 10:22 Ares launch system, 1:37, 3:19, 9:19 Ariane 5 rocket, 4:21 Arianespace SA, 4:21 Armstrong, Neil A., 2:20 Arp 147 (galaxy pair), 2:20 Arp 194 (galaxy group), 8:21 art, cosmology-inspired, 5:10 ASPERA (Astroparticle European Research Area), 1:26 asteroids. See also names of specific asteroids binary, 1:32–33 close approach to Earth, 6:22, 7:19 collision with Jupiter, 11:20 collisions with Earth, 1:24 composition of, 10:55 discovery of, 5:21 effect of environment on surface of, 8:22 measuring distant, 6:23 moons orbiting, -
High-Precision Time-Series Photometry for the Discovery and Characterization of Transiting Exoplanets
University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 5-2015 High-precision time-series photometry for the discovery and characterization of transiting exoplanets. Karen Alicia Collins 1962- University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Astrophysics and Astronomy Commons, and the Physics Commons Recommended Citation Collins, Karen Alicia 1962-, "High-precision time-series photometry for the discovery and characterization of transiting exoplanets." (2015). Electronic Theses and Dissertations. Paper 2104. https://doi.org/10.18297/etd/2104 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. HIGH-PRECISION TIME-SERIES PHOTOMETRY FOR THE DISCOVERY AND CHARACTERIZATION OF TRANSITING EXOPLANETS By Karen A. Collins B.S., Georgia Institute of Technology, 1984 M.S., Georgia Institute of Technology, 1990 M.S., University of Louisville, 2008 A Dissertation Submitted to the Faculty of the College of Arts and Sciences of the University of Louisville in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Physics Department of Physics and Astronomy University of Louisville Louisville, Kentucky May 2015 HIGH-PRECISION TIME-SERIES PHOTOMETRY FOR THE DISCOVERY AND CHARACTERIZATION OF TRANSITING EXOPLANETS By Karen A. Collins B.S., Georgia Institute of Technology, 1984 M.S., Georgia Institute of Technology, 1990 M.S., University of Louisville, 2008 A Dissertation Approved On April 17, 2015 by the following Dissertation Committee: Dissertation Director Dr.