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ìMň Armillary Sphere (1:1) P7 GɌ Ɍ ìň͈éƼP͵˲ɗňˢľ:C?·XZ#Z9YŹXŹ·:ň%P ˊ9˥ɚƮoŅ=ϝŋ@365¼̑ 8oXƷ=ŋV°PVLc 7 GɌZɌůPʂčͦɌ:5o+βϏľŶƙ˲dz͔\#Ź·Yēň% #ɍD(ƙE ł-·365¼̀ɰŲ S9Ʒ=ŋ?ϟ LɌZL?ɌZͥ˛čͦɌůǩͦɌľ`5̌͵Cūɫƭ˛ƕ9Ź·Vͥň% PRȓƙ·365¼̑ Horizon Circle A horizontal ring with 4 wei, 8 gan and VͥoZPƭů͛Ͳ5CYēň9ūɫƭ˛ƕ Meridian Circle A vertical split ring along the north-south 12 zhi (totalling 24 cardinal points) Fìň͈ȴʙˊĭŁʔP~RɗǺ(=7ìňɒçĦµ̮ʌ"dzGÓɗȜ̑ direction with graduations of 365¼ degrees inscribed on the outer surface and 12 fenye on each side (As the ancient Chinese determined (kingdoms and regions) on the inner surface The Armillary Sphere is an astronomical instrument for that there are 365¼ days in a year, the full measuring the position of celestial objects. It comprises circumference of the sky is assigned as three sets of rings. The outermost one is called the 365¼ degrees) Liuheyi (Sphere of the Six Cardinal Points) which consists of the Meridian Circle, Horizon Circle and Fixed Equatorial Circle welded together securely on a supporting framework. The middle one is :ň the Sanchenyi (Sphere of the Three Stellar Objects) with its four components, namely, the Sphere of the Solstitial Colure Circle, Equinoctial Colure Six Cardinal Points Circle, Mobile Equatorial Circle and Ecliptic Circle joining together and rotating as a whole PʂčͦɌ around the polar axis. The innermost set which can rotate within the Sanchenyi around the .P̸čͦ polar axis is called the Siyouyi (Sphere of the \ŋVLòēEWŋ Four Movements) with the Hour-angle Circle, ̀XWŋo Celestial Axis and Sighting Tube. Fixed Equatorial Circle This is a replica of the Armillary Sphere of the Yuan Corresponding to the celestial Dynasty (1279-1368) which was reproduced in the equator with graduations of Ming Dynasty (1368-1644) and is currently locating at 100 marks for 12 double hours, the Purple Mountain Observatory in Nanjing. It has been so also called the ring of 100 marks adapted for use at the latitude of Hong Kong. 香港太空館制作produced by Hong Kong Space Museum ͤM( Operation IJ"òQ"͛^ªʵʎǒįéƼP͵=ɗƥ͉ƕȭͥ˛čͦɌβ.ɗLV To measure the coordinates of a particular celestial object, we first use the Sighting Tube to locate the first determinative star to the west of the target. Then rotate the Mobile Equatorial Circle so that PɬT"͛Φ,ƿͥ˛čͦɌ̶ŝOɬ̑ĦVͥɌ̶ŝBɫ̑"ŝʑŇ the determinative star aligns with the mansion it belongs. After that, use the Sighting Tube to observe P̸Äƿ˲ the target star. Its celestial coordinates, namely, the “mansion extension” and “polar angle”, can then be read from the Mobile Equatorial Circle and the Hour-angle Circle respectively. L?Ɍ ǩͦɌ φơP̸ˊ9ɫůǩͦɌ .ǩͦɗƮo Pƭ 9Ʒ=?7ŋ@ ̈́?Mυ?Ġɗ8o ȴɫƭɗŅ˸ LVPɬMLVV˥ę Equinoctial Colure Circle ʕΉ͛ A ring passing through Ecliptic Circle Ň#^ƕȭ the celestial poles 9 A split ring Celestial Axis and equinoxes North corresponding of the Ecliptic to the ecliptic with A split bar along Circle 28 lunar mansions the polar axis allowing and 24 solar terms the Sighting Tube to LɌ marked on the turn on its centre ˊ9Ʈo inner surfaces φơǩͦɌ Vͥo ͥ˛čͦɌ M0Ġ ˊ ˊ9Ʈo South .P̸ ͛ Ņ=ʓP̸ˊɫǤ ʓP̸ˊɫǤŋ čͦ\ŋLVPɬ ʕ #NJ ŋ<ŲP1825/8̑ <ŲP1825/8̑ @ȓT(·ʍˢ Solstitial Colure Circle ɗůƥ̑ Hour-angle Circle A north-south split ring Mobile Equatorial Circle A north-south split ring Sighting Tube A rectangular tube intersecting with the solstices of Corresponding to the with graduations of 1825/8 Vͥň the Ecliptic Circle and having Yēň celestial equator with degrees for half circle with a circular hole 5 at the centre serving graduations of 182 /8 degrees for Sphere of the markings of the names starting from the ÄÅÆÇÈÇMÉÊMËÆÇ half circle which start from the and boundaries of south celestial pole as a pointing device south celestial pole on each side Three Stellar Objects the 28 lunar mansions ÌÉÍÈMÎÉÏÇÐÇÑËÒ 香港太空館制作produced by Hong Kong Space Museum #ɍD(ɗčͦÄƿùͫ"3Oɬ̑4ů3Bɫ̑4Ķƿ0#ɍɰPčͦʛʎ͉ɢ?· #ɍǰͫŴ. LVPɬÈɬεEēƥ͉P͵ɗOɬ̶̶͈̑P͵Ä^ȟβʑɗƥ͉ɗčˬ¿B Traditional Chinese Naming for Directions ɫ̑˄̶͈P͵ÄP̸9ɫɗnć North 9 In the ancient Chinese equatorial coordinate system, the positions are expressed in mansion qian 乾 gen extension and polar angle. Ancient Chinese divided the region along the celestial equator into 艮 zi ren gui 28 lunar mansions from each of which a determinative star is chosen as a reference. The mansion ren gui 癸 壬 V° extension of a celestial object is the difference in right ascension between the object and its nearest hai 子 癸 壬 chou 4 wei (dimension) determinative star to the west while its polar angle is the angle measuring from the north celestial pole. zi xin 辛 qian 丑 亥 hai 甲 jia gen 子 chou 乾 P̸9ɫMNorth celestial pole 艮 P 丑 亥 xu 8 gan (stems or yin xu 寅 戌 Heavenly Stems) PolarBɫ̑ angle yin 寅 戌 xin 甲 辛 jia P͵ West you you 卯 卯 Celestial 酉 酉 ȅ East mao object mao VLc geng 庚 乙 12 zhi (branches or yi shen 申 辰 Earthly Branches) shen 申 辰 chen ƥ͉ 未 巳 坤 巽 chen LVV Determinative geng kun wei 午 star 庚 si 24 cardinal points 未 巳 yi čͦɌ wu xun 乙 Celestial equator wei 丁 丙 Oɬ̑ 午 si 丁 ding 丙 Mansion ding wu bing bing extension kun坤 巽 xun ˊ South 香港太空館制作produced by Hong Kong Space Museum ¨òē?·õõŋ #ɍǰͫòNJŴ. È_òē?·ʉZŅ_òͪÈͪV ŋEŋùEŋβʳdz:?&E ŋǜò Traditional Chinese Naming for Time ē@õõ ŋ òēMýMÈòēòͪMýM ŋŋùMýMMýM1/6 ŋüMïMõõ ŋ M VLòēM 12 double hoursM ̺(òNJMùòü ( ) How to divide 12 double hours to 100 equal parts (ke)? time hour Each double hour is divided into two hours: the initial and central one. Each hour is represented by 4 M M zi 23-01 big marks and 1 small mark (meaning 1/6 of a big mark). Therefore 12 double hours can be divided into 100 marks. M M chou 01-03 ( 1 ) 12 double hours x 2 hours per double hour x 4 big marks and 1 small mark 12 x 2 x 4 /6 = 100 big marks M ɩM yin 03-05 M @M mao 05-07 MēM chen 07-09 VLòē 12 double hours chou (01h-03h) zi (23h-01h) M M si 09-11 ʉ ʉ MGM wu 11-13 central initial central initial M M wei 13-15 M 'M shen 15-17 M ĞM you 17-19 ŋïM1/6 ŋ ŋ 1 small mark = 1/6 big mark 4 big marks M 3M xu 19-21 M <M hai 21-23 香港太空館制作produced by Hong Kong Space Museum Mʊ M Want to Know More Gnomon (1:2) The gnomon of the Ming Dynasty (1368-1644) was modified in theQing Dynasty (1644-1911) with an ʊ͈#ɍD^b͈ŧ8ɗP~ňˢ%3ʊ4ů34Ͳ5ʊ͈ɚ3ɗƿà increase in its height. Atop the gnomon was a copper leaf with a round pinhole. At noon, sun ray ͈ˊ9DZɗW"ĶƼ̑Rǐʙ²ʊòǒ±²ɗƇ ɗʕ̑ʊC"ĶéƙZE reached the gui through the hole so that the length of the shadow of the gnomon could be measured. As the height of the gnomon was increased, the gui was not long enough for measurement. So an -ɗʕ̑ZƜƙLVV˥ęɗ°ıFʊ͈ẵˊĭŁʔP~RɗǺ(ʊ=ç additional standing gui was erected at the northern end of the gui. Since then, the total length of the ͤM( gnomon’s shadow could be computed by simple geometry. E-#GƇʕɗ ͈0`ģɗ͈"ͮϋOʌ"dz9 łȣ"9 ʊƇʕ ȲγGÓϋĪdz9 łȣ"ˊɗȲƇģɗEPĦʠ total length of ʊȍ shadow of gnomon height of gnomon ɛEĠĠ ʕ ʊȍ 3Ƈȍ ̌±dz7cǺ(ǒçɗʊò¨ʊµȍ\@ě̐#NJLjEȓTGòRǐƇ length of gui height of gnomon height of shadow ʊ ˬͮȓT²ŏ=ʧCɚʵéƼʊƇɗʕ̑ʊ5ơ̏Äͨʑʕ̑"ďǒ"9 on standing gui biao (gnomon) N5E_3ǹŧ8ɗi<.ʧCˀ2ʊƇʕ The gnomon is the oldest and simplest astronomical instrument used in China. It is composed of a vertical biao (gnomon) and a north-south aligned ruler gui lying horizontally to measure the length of the gnomon’s shadow projected by sunshine. The gnomon can be used to determine the direction, length of a year and dates of the solar terms, etc. This is the replica of a gnomon produced in Ming ʊȍ Dynasty which is currently displayed at the Purple Mountain Observatory in Nanjing. 3 height of gnomon standing gui Operation The day at noon with the longest shadow is the winter solstice while the one with the shortest shadow 3Ƈȍ ʕ is the summer solstice. However, this only applies to the regions to the north of the Tropic of Cancer. height of shadow length of gui The day with the shortest shadow does not fall on the summer solstice for places located south of on standing gui the Tropic of Cancer like Hong Kong. Mgui ʊƇʕ total length of shadow of gnomon 香港太空館制作produced by Hong Kong Space Museum čͦ.­ Equatorial Sundial (1:1) 9 ù ü čͦ.­ A3'4 %­=ůEă­ǼͲ5­=@òNJŋ̑­Ǽ˥ɚdz­=čͦ. North ­ɗ­=Ä̸čͦ=A­=ɗDz˗ć̑·Hõ̑ÝBʳȜ̑ = GRǐ Horizon F­͈ẵ9ĭ̀®Růɻˁɗčͦ­=çĦ¹µʌ"dzGÓȜ̑ Direction of the Sun at noon during summer solstice ͤM( ­Ǽ Rǐʙ²­ǼòOʓ­=\ɗ±ƇʧC̶ŝʳòɗòNJ̈́?υ?°NJRǐɤʙ² Stylus ­=ù9=ü`υ?̈́?°NJ˄ɤʙϟ=ùˊ=ü ­=ùčͦ=ü An equatorial sundial is composed of a template with time markings and a stylus erected perpendicularly Template (parallel to equator) to the template. The template is parallel to the equator, i.e. inclined at an angle of 90 degrees minus the 90˚- latitude. 90˚- latitude ɢ͗ This sundial is a replica of the one placed outside the Hall of Supreme Harmony in the Imperial Palace in Ȝ̑ Beijing with adaptation made by referencing to the latitude of Hong Kong.
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    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 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.