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A Multislit Photoelectric Star Micrometer for the Meridian Circle of the Nikolayev Astronomical Observatory
A Multislit Photoelectric Star Micrometer for the Meridian Circle of the Nikolayev Astronomical Observatory. V. V. Konin and A. D. Pogonij Nikolaev Astronomical Observatory, Nikolaev, USSR In the course of the cooperation between the Nikolaev and the Pulkovo Observatories, a photoelectric micrometer, similar to that proposed by E. Htfg, was designed and installed on the Repsold meridian circle. The optics of the finder includes an achromatic wedge for the deflection of light from the objective to the finderTs eyepiece. The grating is composed only of a system of inclined slits (Hrfg 1970, p. 92, No. 2). The slits are 5V3 wide and spaced at 38V3. One can use from 7 to 14 slit pairs in the micrometer for observations. A rectangular diaphragm isolates an element of 19" x 27" from the working grating. This has 4 initial positions. The required initial position depends on the instrument's position, the type of culmination and the observing interval (30s or 60s for an equatorial star). The diaphragm is moved by a stepping motor, whose speed of rotation is controlled by the observer and depends on declination. The motor can be switched on either by hand or automatically after the star appears in the field defined by the diaphragm. During transit, the clock readings of the start and the end of the observation are recorded with a precision of 0? 001. Photon counts are taken for every 0S1 time interval. There is a block for recording contact signals from a moving mark in the control unit (Konin et al., 1982). Karyakina et al. -
The Oscillating Slit Micrometer of the Meridian Circle Pmc 190 Tokyo
THE OSCILLATING SLIT MICROMETER OF THE MERIDIAN CIRCLE PMC 190 TOKYO C. Kuhne, Carl Zeiss, D-7082 Oberkochen, Federal Republic of Germany M. Miyamoto, M. Yoshizawa, Tokyo Astronomical Observatory, Mitaka, Tokyo 181, Japan ABSTRACT The meridian circle installed at the Tokyo Astronomical Observatory in 1982/83 is equipped with a photoelectric Double Slit Micrometer which is one of the basic prerequisites for fully automatic observation. A slit plate is located in the image field of the telescope. It oscil lates parallel to right ascension while being guided at the mean tra veling speed of the star. The paper describes the procedure by which the moment of the star pas sage through the instruments meridian and declination is determined. Furthermore, the autocollimation devices are described which are an essential prerequisite for the determination and periodical checking of the instrumental errors. Also, the measuring devices for the passage of the sun and the moon are dealt with briefly. 1 . INTRODUCTION The Double Slit Micrometer was introduced in 1972 by the first author during the engineering phase of the meridian circle project. The con cept is based on the multislit micrometer used by E. H<6g (1970) at the meridian circle in Perth. The +_ 45° inclination was retained, but the multitude of slits was replaced by only one movable pair. Therefore, the system became independent of the starfs velocity, a higher degree of statistic averaging could be applied, and a more simple and stable kind of collimation measurement became available. 2. DESIGN PRINCIPLE The telescope of the PMC 190 has a double-walled tube whose inner part houses the objective and the section of the micrometer which has to per- 379 H. -
Implementing Eratosthenes' Discovery in the Classroom: Educational
Implementing Eratosthenes’ Discovery in the Classroom: Educational Difficulties Needing Attention Nicolas Decamp, C. de Hosson To cite this version: Nicolas Decamp, C. de Hosson. Implementing Eratosthenes’ Discovery in the Classroom: Educational Difficulties Needing Attention. Science and Education, Springer Verlag, 2012, 21 (6), pp.911-920. 10.1007/s11191-010-9286-3. hal-01663445 HAL Id: hal-01663445 https://hal.archives-ouvertes.fr/hal-01663445 Submitted on 18 Dec 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Sci & Educ DOI 10.1007/s11191-010-9286-3 Implementing Eratosthenes’ Discovery in the Classroom: Educational Difficulties Needing Attention Nicolas De´camp • Ce´cile de Hosson Ó Springer Science+Business Media B.V. 2010 Abstract This paper presents a critical analysis of the accepted educational use of the method performed by Eratosthenes to measure the circumference of Earth which is often considered as a relevant means of dealing with issues related to the nature of science and its history. This method relies on a number of assumptions among which the parallelism of sun rays. The assumption of sun rays parallelism (if it is accurate) does not appear spontaneous for students who consider sun rays to be divergent. -
Chapter 7 Mapping The
BASICS OF RADIO ASTRONOMY Chapter 7 Mapping the Sky Objectives: When you have completed this chapter, you will be able to describe the terrestrial coordinate system; define and describe the relationship among the terms com- monly used in the “horizon” coordinate system, the “equatorial” coordinate system, the “ecliptic” coordinate system, and the “galactic” coordinate system; and describe the difference between an azimuth-elevation antenna and hour angle-declination antenna. In order to explore the universe, coordinates must be developed to consistently identify the locations of the observer and of the objects being observed in the sky. Because space is observed from Earth, Earth’s coordinate system must be established before space can be mapped. Earth rotates on its axis daily and revolves around the sun annually. These two facts have greatly complicated the history of observing space. However, once known, accu- rate maps of Earth could be made using stars as reference points, since most of the stars’ angular movements in relationship to each other are not readily noticeable during a human lifetime. Although the stars do move with respect to each other, this movement is observable for only a few close stars, using instruments and techniques of great precision and sensitivity. Earth’s Coordinate System A great circle is an imaginary circle on the surface of a sphere whose center is at the center of the sphere. The equator is a great circle. Great circles that pass through both the north and south poles are called meridians, or lines of longitude. For any point on the surface of Earth a meridian can be defined. -
Planetary Diagrams — Descriptions, Models, Theories: from Carolingian Deployments to Copernican Debates
Planetary Diagrams — Descriptions, Models, Theories: from Carolingian Deployments to Copernican Debates Bruce Eastwood and Gerd Graßhoff Contents 1 Introduction . 1 2 The Beginnings in Carolingian Europe . 1 2.1 Astronomy and Computus before 800 . 1 2.2 Schools and Texts . 3 2.3 Diagrams and the Study of Texts . 7 2.4 Dynamics of Diagrams: Calcidius and Pliny . 7 2.5 Dynamics of Diagrams: Martianus Capella . 21 3 Qualitative Theory in the High and Later Middle Ages . 29 3.1 Dynamics of Diagrams: Construction of a Planetary The- ory............................ 29 3.2 The Capellan Tradition through the Fifteenth Century . 32 4 Merging Two Traditions: The Sixteenth Century . 37 1 INTRODUCTION Through three distinct periods from ca. 800 to ca. 1600 we find that European as- tronomers were concerned with questions about the planets that involved the dis- cussion and invention of models without quantitative expression. This qualitative tradition was first developed in the ninth century in the course of studying ancient Latin texts on cosmology and astronomy. The diagrams, used to represent different phenomena and aspects of planetary motion, continued as long as they were found useful for teaching, for exposing questions, or for proposing theoretical positions. The history of this tradition of planetary diagrams indicates a constant concern for qualitative theory and the co-existence of both qualitative and quantitative plane- tary theory after the introduction of the Greco-Arabic mathematical tradition of planetary astronomy in twelfth-century Europe. In the sixteenth century the same qualitative tradition continued as a source for approaches to new phenomena and problems. 2 THE BEGINNINGS IN CAROLINGIAN EUROPE 2.1 ASTRONOMY AND COMPUTUS BEFORE 800 From the sixth century to the twelfth century in Western Europe there was no direct influence of Greek works in the exact sciences. -
The Geography of Ptolemy Elucidated
The Grography of Ptolemy The geography of Ptolemy elucidated Thomas Glazebrook Rylands 1893 • A brief outline of the rise and progress of geographical inquiry prior to the time of Ptolemy. §1.—Introductory. IN tracing the early progress of Geography it is necessary to remember that, like all other sciences, it arose from “ small beginnings.” When men began to move from place to place they naturally desired to tell the tale of their wanderings, both for their own satisfaction and for the information of others. Such accounts have now perished, but their results remain in the earliest records extant ; hence, it is impossible to begin an investigation into the history of Geography at the true fountain-head, though it is in some instances possible to guess the nature of the source from the character of the resultant stream. A further difficulty lies in the question as to where the science of Geography begins. A Greek would probably have answered when some discoverer first invented a method for map- ping out the distance between certain places, which distance conversely could be ascertained directly from the map. In accordance with modern method, the science of Geography might be said to begin when the subject ceased to be dealt with mythically or dogmatically ; when facts were collected and reduced to laws, while these laws again, or their prior facts, were connected with other laws—in the case of Geography with those of Mathematics and Astro- nomy. Perhaps it would be better to follow the latter principle of division, and consequently the history of Geography may be divided into two main stages—“ Pre-Scientific” and Scientific Geography—though strictly speaking, the name of Geography should be applied to the latter alone. -
Thinking Outside the Sphere Views of the Stars from Aristotle to Herschel Thinking Outside the Sphere
Thinking Outside the Sphere Views of the Stars from Aristotle to Herschel Thinking Outside the Sphere A Constellation of Rare Books from the History of Science Collection The exhibition was made possible by generous support from Mr. & Mrs. James B. Hebenstreit and Mrs. Lathrop M. Gates. CATALOG OF THE EXHIBITION Linda Hall Library Linda Hall Library of Science, Engineering and Technology Cynthia J. Rogers, Curator 5109 Cherry Street Kansas City MO 64110 1 Thinking Outside the Sphere is held in copyright by the Linda Hall Library, 2010, and any reproduction of text or images requires permission. The Linda Hall Library is an independently funded library devoted to science, engineering and technology which is used extensively by The exhibition opened at the Linda Hall Library April 22 and closed companies, academic institutions and individuals throughout the world. September 18, 2010. The Library was established by the wills of Herbert and Linda Hall and opened in 1946. It is located on a 14 acre arboretum in Kansas City, Missouri, the site of the former home of Herbert and Linda Hall. Sources of images on preliminary pages: Page 1, cover left: Peter Apian. Cosmographia, 1550. We invite you to visit the Library or our website at www.lindahlll.org. Page 1, right: Camille Flammarion. L'atmosphère météorologie populaire, 1888. Page 3, Table of contents: Leonhard Euler. Theoria motuum planetarum et cometarum, 1744. 2 Table of Contents Introduction Section1 The Ancient Universe Section2 The Enduring Earth-Centered System Section3 The Sun Takes -
Astronomy and Hipparchus
CHAPTER 9 Progress in the Sciences: Astronomy and Hipparchus Klaus Geus Introduction Geography in modern times is a term which covers several sub-disciplines like ecology, human geography, economic history, volcanology etc., which all con- cern themselves with “space” or “environment”. In ancient times, the definition of geography was much more limited. Geography aimed at the production of a map of the oikoumene, a geographer was basically a cartographer. The famous scientist Ptolemy defined geography in the first sentence of his Geographical handbook (Geog. 1.1.1) as “imitation through drafting of the entire known part of the earth, including the things which are, generally speaking, connected with it”. In contrast to chorography, geography uses purely “lines and label in order to show the positions of places and general configurations” (Geog. 1.1.5). Therefore, according to Ptolemy, a geographer needs a μέθοδος μαθεματική, abil- ity and competence in mathematical sciences, most prominently astronomy, in order to fulfil his task of drafting a map of the oikoumene. Given this close connection between geography and astronomy, it is not by default that nearly all ancient “geographers” (in the limited sense of the term) stood out also as astronomers and mathematicians: Among them Anaximander, Eudoxus, Eratosthenes, Hipparchus, Poseidonius and Ptolemy are the most illustrious. Apart from certain topics like latitudes, meridians, polar circles etc., ancient geography also took over from astronomy some methods like the determina- tion of the size of the earth or of celestial and terrestrial distances.1 The men- tioned geographers Anaximander, Eudoxus, Hipparchus, Poseidonius and Ptolemy even constructed instruments for measuring, observing and calculat- ing like the gnomon, sundials, skaphe, astrolabe or the meteoroscope.2 1 E.g., Ptolemy (Geog. -
Astrometry and Optics During the Past 2000 Years
1 Astrometry and optics during the past 2000 years Erik Høg Niels Bohr Institute, Copenhagen, Denmark 2011.05.03: Collection of reports from November 2008 ABSTRACT: The satellite missions Hipparcos and Gaia by the European Space Agency will together bring a decrease of astrometric errors by a factor 10000, four orders of magnitude, more than was achieved during the preceding 500 years. This modern development of astrometry was at first obtained by photoelectric astrometry. An experiment with this technique in 1925 led to the Hipparcos satellite mission in the years 1989-93 as described in the following reports Nos. 1 and 10. The report No. 11 is about the subsequent period of space astrometry with CCDs in a scanning satellite. This period began in 1992 with my proposal of a mission called Roemer, which led to the Gaia mission due for launch in 2013. My contributions to the history of astrometry and optics are based on 50 years of work in the field of astrometry but the reports cover spans of time within the past 2000 years, e.g., 400 years of astrometry, 650 years of optics, and the “miraculous” approval of the Hipparcos satellite mission during a few months of 1980. 2011.05.03: Collection of reports from November 2008. The following contains overview with summary and link to the reports Nos. 1-9 from 2008 and Nos. 10-13 from 2011. The reports are collected in two big file, see details on p.8. CONTENTS of Nos. 1-9 from 2008 No. Title Overview with links to all reports 2 1 Bengt Strömgren and modern astrometry: 5 Development of photoelectric astrometry including the Hipparcos mission 1A Bengt Strömgren and modern astrometry .. -
A Solstice Sundial
A SOLSTICE SUNDIAL JACKIE JONES arlier this year a group of us went on holiday to It being Wales, one is never sure about the weather, so we South Wales; as the period covered the summer prepared for different methods of establishing the north– E solstice, we decided it should be celebrated in south line. In the hope of a sunny day and being able some form. Following the experience of the sundial on to draw a line from the shadow of a vertical pole, we Crosby Beach just before the BSS Conference in Liverpool calculated how solar noon would relate to watch time. in April 2016,1 I decided another seaside sundial would be Taking into account the longitude, which was 4° west appropriate. equalling 16 minutes; equation of time, dial slow by As with that event, planning the dial and exactly where it 1 minute 42 seconds and the one hour for British Summer will be, in advance, is essential. With the aid of maps and Time gave us a watch time of 13:17:42 – probably a bit Google Earth we located a south-facing sandy beach just a over-accurate for our needs. We also planned to have a few minutes’ walk from where we were staying. The compass, knowing the correction from magnetic to true latitude of the bay is 51° 34ʹ north and we agreed to north. construct a solar-time horizontal dial using only natural On a coastal walk a few days before the solstice, we found materials found nearby. Before leaving home, I drew out on the perfect long sticks needed for the gnomon and supports; metre-wide paper the layout of the afternoon hour lines for we were then fully prepared. -
212 Publications of the Some Pioneer
212 PUBLICATIONS OF THE SOME PIONEER OBSERVERS1 By Frank Schlesinger In choosing a subject upon which to speak to you this eve- ning, I have had to bear in mind that, although this is a meeting of the Astronomical Society of the Pacific, not many of my audience are astronomers, and I am therefore debarred from speaking on too technical a matter. Under these circumstances I have thought that a historical subject, and one that has been somewhat neglected by the, formal historians of our science, may be of interest. I propose to outline, very briefly of course, the history of the advances that have been made in the accuracy of astronomical measurements. To do this within an hour, I must confine myself to the measurement of the relative places of objects not very close together, neglecting not only measure- ments other than of angles, but also such as can be carried out, for example, by the filar micrometer and the interferometer; these form a somewhat distinct chapter and would be well worth your consideration in an evening by themselves. It is clear to you, I hope, in how restricted a sense I am using the word observer ; Galileo, Herschel, and Barnard were great observers in another sense and they were great pioneers. But of their kind of observing I am not to speak to you tonight. My pioneers are five in number ; they are Hipparchus in the second century b.c., Tycho in the sixteenth century, Bradley in the eighteenth, Bessel in the first half of the nineteenth century and Rüther fur d in the second half. -
Our Place in the Universe Sun Kwok
Our Place in the Universe Sun Kwok Our Place in the Universe Understanding Fundamental Astronomy from Ancient Discoveries Second Edition Sun Kwok Faculty of Science The University of Hong Kong Hong Kong, China This book is a second edition of the book “Our Place in the Universe” previously published by the author as a Kindle book under amazon.com. ISBN 978-3-319-54171-6 ISBN 978-3-319-54172-3 (eBook) DOI 10.1007/978-3-319-54172-3 Library of Congress Control Number: 2017937904 © Springer International Publishing AG 2017 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made.