June 2014 BRAS Newsletter
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Astronomie in Theorie Und Praxis 8. Auflage in Zwei Bänden Erik Wischnewski
Astronomie in Theorie und Praxis 8. Auflage in zwei Bänden Erik Wischnewski Inhaltsverzeichnis 1 Beobachtungen mit bloßem Auge 37 Motivation 37 Hilfsmittel 38 Drehbare Sternkarte Bücher und Atlanten Kataloge Planetariumssoftware Elektronischer Almanach Sternkarten 39 2 Atmosphäre der Erde 49 Aufbau 49 Atmosphärische Fenster 51 Warum der Himmel blau ist? 52 Extinktion 52 Extinktionsgleichung Photometrie Refraktion 55 Szintillationsrauschen 56 Angaben zur Beobachtung 57 Durchsicht Himmelshelligkeit Luftunruhe Beispiel einer Notiz Taupunkt 59 Solar-terrestrische Beziehungen 60 Klassifizierung der Flares Korrelation zur Fleckenrelativzahl Luftleuchten 62 Polarlichter 63 Nachtleuchtende Wolken 64 Haloerscheinungen 67 Formen Häufigkeit Beobachtung Photographie Grüner Strahl 69 Zodiakallicht 71 Dämmerung 72 Definition Purpurlicht Gegendämmerung Venusgürtel Erdschattenbogen 3 Optische Teleskope 75 Fernrohrtypen 76 Refraktoren Reflektoren Fokus Optische Fehler 82 Farbfehler Kugelgestaltsfehler Bildfeldwölbung Koma Astigmatismus Verzeichnung Bildverzerrungen Helligkeitsinhomogenität Objektive 86 Linsenobjektive Spiegelobjektive Vergütung Optische Qualitätsprüfung RC-Wert RGB-Chromasietest Okulare 97 Zusatzoptiken 100 Barlow-Linse Shapley-Linse Flattener Spezialokulare Spektroskopie Herschel-Prisma Fabry-Pérot-Interferometer Vergrößerung 103 Welche Vergrößerung ist die Beste? Blickfeld 105 Lichtstärke 106 Kontrast Dämmerungszahl Auflösungsvermögen 108 Strehl-Zahl Luftunruhe (Seeing) 112 Tubusseeing Kuppelseeing Gebäudeseeing Montierungen 113 Nachführfehler -
Binocular Universe: Northern Exposure
Binocular Universe: Northern Exposure March 2013 Phil Harrington he northern circumpolar sky holds many binocular targets that we can enjoy throughout the year. This month, let's take aim at the constellation Ursa TMinor, the Little Bear. You may know it better as the Little Dipper, an asterism made up of the seven brightest stars in the Little Bear. Above: Winter star map from Star Watch by Phil Harrington. Above: Finder chart for this month's Binocular Universe. Chart adapted from Touring the Universe through Binoculars Atlas (TUBA), www.philharrington.net/tuba.htm Call it what you will, this star group is most famous as the home of the North Star, Polaris [Alpha (α) Ursae Minoris]. Earth's rotational axis is aimed just three- quarters of a degree away from Polaris, causing it to trace out a very tiny circle around that invisible point every 24 hours. The North Celestial Pole is slowly moving closer to Polaris. It will continue to close to within 14 minutes of arc around the year 2105, when it will slowly start to pull away. While Polaris is currently the pole star, the 26,000-year wobble of Earth's axis, called precession, causes the Celestial Pole's aim to trace a 47° circle in the sky. For instance, during the building of the pyramids nearly 4,600 years ago, the North Pole was aimed toward the star Thuban in Draco. Fast forward 5,200 years from now and the pole will be point near Alderamin in Cepheus. Most of us at one time or another have heard someone misspeak by referring to Polaris as the brightest star in the night sky. -
THUBAN the Star Thuban in the Constellation Draco (The Dragon) Was the North Pole Star Some 5,000 Years Ago, When the Egyptians Were Building the Pyramids
STAR OF THE WEEK: THUBAN The star Thuban in the constellation Draco (the Dragon) was the North Pole Star some 5,000 years ago, when the Egyptians were building the pyramids. Thuban is not a particularly bright star. At magnitude 3.7 and known as alpha draconis it is not even the brightest star in its constellation. What is Thuban’s connection with the pyramids of Egypt? Among the many mysteries surrounding Egypt’s pyramids are the so-called “air shafts” in the Great Pyramid of Giza. These narrow passageways were once thought to serve for ventilation as the The Great Pyramid of Giza, an enduring monument of ancient pyramids were being built. In the 1960s, though, Egypt. Egyptologists believe that it was built as a tomb for fourth dynasty Egyptian Pharaoh Khufu around 2560 BC the air shafts were recognized as being aligned with stars or areas of sky as the sky appeared for the pyramids’ builders 5,000 years ago. To this day, the purpose of all these passageways inside the Great Pyramid isn’t clear, although some might have been connected to rituals associated with the king’s ascension to the heavens. Whatever their purpose, the Great Pyramid of Giza reveals that its builders knew the starry skies intimately. They surely knew Thuban was their Pole Star, the point around which the heavens appeared to turn. Various sources claim that Thuban almost exactly pinpointed the position of the north celestial pole in the This diagram shows the so-called air shafts in the Great year 2787 B.C. -
The Planisphere of the Heavens
The Planisphere of the Heavens by Steven E. Behrmann Book V Copyright© by Steven E. Behrmann All rights reserved 2010 First Draft (Sunnyside Edition) Dedication: This book is dedicated to my blessed little son, Jonathan William Edward, to whom I hope to teach the names of the stars. Table of Contents A Planisphere of the Heavens .......................................................... 12 The Signs of the Seasons ................................................................. 15 The Virgin (Virgo) ........................................................................... 24 Virgo ............................................................................................ 25 Coma ............................................................................................ 27 The Centaur .................................................................................. 29 Boötes ........................................................................................... 31 The Scales (Libra) ............................................................................ 34 Libra ............................................................................................. 35 The Cross (Crux) .......................................................................... 37 The Victim ................................................................................... 39 The Crown .................................................................................... 41 The Scorpion ................................................................................... -
Enabling Science with Gaia Observations of Naked-Eye Stars
Enabling science with Gaia observations of naked-eye stars J. Sahlmanna,b, J. Mart´ın-Fleitasb,c, A. Morab,c, A. Abreub,d, C. M. Crowleyb,e, E. Jolietb,f aEuropean Space Agency, STScI, 3700 San Martin Drive, Baltimore, MD 21218, USA; bEuropean Space Agency, ESAC, P.O. Box 78, Villanueva de la Canada,˜ 28691 Madrid, Spain; cAurora Technology, Crown Business Centre, Heereweg 345, 2161 CA Lisse, The Netherlands; dElecnor Deimos Space, Ronda de Poniente 19, Ed. Fiteni VI, 28760 Tres Cantos, Madrid, Spain; eHE Space Operations BV, Huygensstraat 44, 2201 DK Noordwijk, The Netherlands; fCalifornia Institute of Technology, Pasadena, CA, 91125, USA ABSTRACT ESA’s Gaia space astrometry mission is performing an all-sky survey of stellar objects. At the beginning of the nominal mission in July 2014, an operation scheme was adopted that enabled Gaia to routinely acquire observations of all stars brighter than the original limit of G∼6, i.e. the naked-eye stars. Here, we describe the current status and extent of those observations and their on-ground processing. We present an overview of the data products generated for G<6 stars and the potential scientific applications. Finally, we discuss how the Gaia survey could be enhanced by further exploiting the techniques we developed. Keywords: Gaia, Astrometry, Proper motion, Parallax, Bright Stars, Extrasolar planets, CCD 1. INTRODUCTION There are about 6000 stars that can be observed with the unaided human eye. Greek astronomer Hipparchus used these stars to define the magnitude system still in use today, in which the faintest stars had an apparent visual magnitude of 6. -
Dhruva the Ancient Indian Pole Star: Fixity, Rotation and Movement
Indian Journal of History of Science, 46.1 (2011) 23-39 DHRUVA THE ANCIENT INDIAN POLE STAR: FIXITY, ROTATION AND MOVEMENT R N IYENGAR* (Received 1 February 2010; revised 24 January 2011) Ancient historical layers of Hindu astronomy are explored in this paper with the help of the Purân.as and the Vedic texts. It is found that Dhruva as described in the Brahmân.d.a and the Vis.n.u purân.a was a star located at the tail of a celestial animal figure known as the Úiúumâra or the Dolphin. This constellation, which can be easily recognized as the modern Draco, is described vividly and accurately in the ancient texts. The body parts of the animal figure are made of fourteen stars, the last four of which including Dhruva on the tail are said to never set. The Taittirîya Âran.yaka text of the Kr.s.n.a-yajurveda school which is more ancient than the above Purân.as describes this constellation by the same name and lists fourteen stars the last among them being named Abhaya, equated with Dhruva, at the tail end of the figure. The accented Vedic text Ekâgni-kân.d.a of the same school recommends observation of Dhruva the fixed Pole Star during marriages. The above Vedic texts are more ancient than the Gr.hya-sûtra literature which was the basis for indologists to deny the existence of a fixed North Star during the Vedic period. However the various Purân.ic and Vedic textual evidence studied here for the first time, leads to the conclusion that in India for the Yajurvedic people Thuban (α-Draconis) was Dhruva the Pole Star c 2800 BC. -
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. -
The Mason Dixon Land Survey
Historic American Land Surveys: The Mason Dixon Land Survey 4 Hours PDH Academy PO Box 449 Pewaukee, WI 53072 (888) 564-9098 www.pdhacademy.com HISTORIC AMERICAN LAND SURVEYS – THE MASON-DIXON LINE SURVEY BY: NATHAN J. WALKER, PLS Objective: As the retracement surveyors of today are called upon to “follow in the footsteps” of those original surveyors who went before, it is useful and instructive to learn how and why the early surveyors conducted their projects. It is likewise worthwhile to consider the outcomes and consequences of the early land surveys that shaped and continue to influence America. This course seeks to study the historically important Mason-Dixon Line survey, the circumstances that led to the necessity of the survey, the surveyors who conducted the survey, and the methods and techniques they employed to complete their daunting project. Also, the lasting political and cultural effects of the survey will be examined and a timeline of events relating to the survey will be presented. Course Outline: The Mason-Dixon Line Survey A. Biographical Overview of Charles Mason B. Biographical Overview of Jeremiah Dixon C. Mason and Dixon’s Initial Expedition Section 1 – Historical Background 1. The Province of Maryland 2. The Province of Pennsylvania 3. The Penn-Calvert Boundary Dispute Section 2 – Surveying the Lines 1. Scope of the Survey 2. Celestial Observation and a Commencing Point 3. The Point of Beginning 4. The Tangent Line 5. The West Line and the North Line 6. Extending the West Line Section 3 – Lasting Effects of the Survey 1. The Delaware Wedge 2. -
On the Reduction of Star Places by Bohnenberger's Method
21 2834 22 6. Beispiel. 7 Ziffergruppen. Elliptische Elemente eines Cometen. Comet Ellipse 09902 November 19779 11757 18123 Elliptische Elemente des neuen Cometen : I4449 19250 93260. T = November I 9.7 79 M. Z. Berlin Oppenheim. (D = 117'57' = 181 23 M. Aequ. des Jahresanfangs i= I44 49 q 1.9250 1 = e = 0.9902 Opperikeim. Anmerkung. Das 5. und 6. Beispiel bezieht sich auf die von Dr. S. Oppenheim in A. N. 2692 mitgetheilten parabolischen resp. elliptischen Elemente des Cometen 1881VIII. A. Krzlegcr. On t'he Reduction of Stsr Places by Bohnenberger's Method. By Professor Truman Henry Saford.*) Every astronomer who has had much to do with the Using similar considerations I have been in the habit reduction of star places from one epoch to another is of selecting the epochs for the use of Bohnenberger's for- aware that in case the star be very near the pole, or the mula as follows. epochs very distant, the method invented by Bohnen- We have tables for the secular variation, and for the berger must replace the ordinary employment of annual term multiplied by the third power of the time. While precessions and secular variations. these tables are not quite complete enough for close polar It is easy enough to see that when the product of stars, they are a very great help in checking calculations, the interval by the tangent of the star's declination reaches and it is easy enough to use them or to calculate the terms a certain amount the precession series is no longer con- depending upon the third, and by their variations from year vergent. -
Exoplanet.Eu Catalog Page 1 # Name Mass Star Name
exoplanet.eu_catalog # name mass star_name star_distance star_mass OGLE-2016-BLG-1469L b 13.6 OGLE-2016-BLG-1469L 4500.0 0.048 11 Com b 19.4 11 Com 110.6 2.7 11 Oph b 21 11 Oph 145.0 0.0162 11 UMi b 10.5 11 UMi 119.5 1.8 14 And b 5.33 14 And 76.4 2.2 14 Her b 4.64 14 Her 18.1 0.9 16 Cyg B b 1.68 16 Cyg B 21.4 1.01 18 Del b 10.3 18 Del 73.1 2.3 1RXS 1609 b 14 1RXS1609 145.0 0.73 1SWASP J1407 b 20 1SWASP J1407 133.0 0.9 24 Sex b 1.99 24 Sex 74.8 1.54 24 Sex c 0.86 24 Sex 74.8 1.54 2M 0103-55 (AB) b 13 2M 0103-55 (AB) 47.2 0.4 2M 0122-24 b 20 2M 0122-24 36.0 0.4 2M 0219-39 b 13.9 2M 0219-39 39.4 0.11 2M 0441+23 b 7.5 2M 0441+23 140.0 0.02 2M 0746+20 b 30 2M 0746+20 12.2 0.12 2M 1207-39 24 2M 1207-39 52.4 0.025 2M 1207-39 b 4 2M 1207-39 52.4 0.025 2M 1938+46 b 1.9 2M 1938+46 0.6 2M 2140+16 b 20 2M 2140+16 25.0 0.08 2M 2206-20 b 30 2M 2206-20 26.7 0.13 2M 2236+4751 b 12.5 2M 2236+4751 63.0 0.6 2M J2126-81 b 13.3 TYC 9486-927-1 24.8 0.4 2MASS J11193254 AB 3.7 2MASS J11193254 AB 2MASS J1450-7841 A 40 2MASS J1450-7841 A 75.0 0.04 2MASS J1450-7841 B 40 2MASS J1450-7841 B 75.0 0.04 2MASS J2250+2325 b 30 2MASS J2250+2325 41.5 30 Ari B b 9.88 30 Ari B 39.4 1.22 38 Vir b 4.51 38 Vir 1.18 4 Uma b 7.1 4 Uma 78.5 1.234 42 Dra b 3.88 42 Dra 97.3 0.98 47 Uma b 2.53 47 Uma 14.0 1.03 47 Uma c 0.54 47 Uma 14.0 1.03 47 Uma d 1.64 47 Uma 14.0 1.03 51 Eri b 9.1 51 Eri 29.4 1.75 51 Peg b 0.47 51 Peg 14.7 1.11 55 Cnc b 0.84 55 Cnc 12.3 0.905 55 Cnc c 0.1784 55 Cnc 12.3 0.905 55 Cnc d 3.86 55 Cnc 12.3 0.905 55 Cnc e 0.02547 55 Cnc 12.3 0.905 55 Cnc f 0.1479 55 -
Rocznik Astronomiczny 2002
INSTYTUT GEODEZJI I KARTOGRAFII ROCZNIK IGiK ASTRONOMICZNY 2002NA ROK INSTYTUT GEODEZJI I KARTOGRAFII ROCZNIK ASTRONOMICZNY NA ROK 2002 LVII WARSZAWA 2001 Rada Wydawnicza przy Instytucie Geodezji i Kartografii Adam Linsenbarth (przewodniczący), Andrzej Ciołkosz (zast. przewodniczącego), Teresa Baranowska, Stanisław Białousz (Wydział Geodezji i Kartografii PW), Hanna Ciołkosz (sekretarz), Wojciech Janusz, Jan R. Olędzki (Wydział Geografii i Studiów Regionalnych UW), Andrzej Sas–Uhrynowski, Karol Szeliga, Janusz Zieliński (Centrum Badań Kosmicznych) Redaktor naukowy Rocznika Astronomicznego Jan Kryński Sekretarz: Marcin Sękowski Okładkę projektował Łukasz Żak Adres Redakcji: Instytut Geodezji i Kartografii Warszawa, ul. Jasna 2/4 email: [email protected] http: www.igik.edu.pl ISSN 0209-0341 INSTYTUT GEODEZJI I KARTOGRAFII Arkuszy wydawniczych 24.85. Papier offsetowy kl. III, g 90, 707–500 mm. Do druku od- dano 14.XII.2001 r. Druk ukończono w grudniu 2001 r. na zamówienie ZAGiGS/IGiK/2001 DRUK: INSTYTUT GEODEZJI I KARTOGRAFII — WARSZAWA, ul. Jasna 2/4 SPIS TREŚCI Przedmowa .................................................................................. 5 Skróty stosowane w Roczniku Astronomicznym .............................................. 6 Dni świąteczne, pory roku, stałe precesyjne, obserwatoria astronomiczne ...................... 7 Czas gwiazdowy Greenwich .............................................................. 8÷11 Słońce, współrzędne równikowe, wschody i zachody w Warszawie ........................ 12÷19 Księżyc, współrzędne równikowe, -
Planetary Companions Around the K Giant Stars 11 Ursae Minoris and HD 32518
A&A 505, 1311–1317 (2009) Astronomy DOI: 10.1051/0004-6361/200911702 & c ESO 2009 Astrophysics Planetary companions around the K giant stars 11 Ursae Minoris and HD 32518 M. P. Döllinger1, A. P. Hatzes2, L. Pasquini1, E. W. Guenther2, and M. Hartmann2 1 European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany e-mail: [email protected] 2 Thüringer Landessternwarte Tautenburg, Sternwarte 5, 07778 Tautenburg, Germany Received 22 January 2009 / Accepted 10 August 2009 ABSTRACT Context. 11 UMi and HD 32518 belong to a sample of 62 K giant stars that has been observed since February 2004 using the 2m Alfred Jensch telescope of the Thüringer Landessternwarte (TLS) to measure precise radial velocities (RVs). Aims. The aim of this survey is to investigate the dependence of planet formation on the mass of the host star by searching for plane- tary companions around intermediate-mass giants. Methods. An iodine absorption cell was used to obtain accurate RVs for this study. Results. Our measurements reveal that the RVs of 11 UMi show a periodic variation of 516.22 days with a semiamplitude of −1 −7 K = 189.70 m s . An orbital solution yields a mass function of f (m) = (3.608 ± 0.441) × 10 solar masses (M) and an eccentricity of e = 0.083 ± 0.03. The RV curve of HD 32518 shows sinusoidal variations with a period of 157.54 days and a semiamplitude of −1 −8 K = 115.83 m s . An orbital solution yields an eccentricity, e = 0.008 ± 0.03 and a mass function, f (m) = (2.199 ± 0.235) × 10 M.