The Magic of the Atwood Sphere
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Scienza E Cultura Universitalia
SCIENZA E CULTURA UNIVERSITALIA Costantino Sigismondi (ed.) ORBE NOVUS Astronomia e Studi Gerbertiani 1 Universitalia SIGISMONDI, Costantino (a cura di) Orbe Novus / Costantino Sigismondi Roma : Universitalia, 2010 158 p. ; 24 cm. – ( Scienza e Cultura ) ISBN … 1. Storia della Scienza. Storia della Chiesa. I. Sigismondi, Costantino. 509 – SCIENZE PURE, TRATTAMENTO STORICO 270 – STORIA DELLA CHIESA In copertina: Imago Gerberti dal medagliere capitolino e scritta ORBE NOVVS nell'epitaffio tombale di Silvestro II a S. Giovanni in Laterano (entrambe le foto sono di Daniela Velestino). Collana diretta da Rosalma Salina Borello e Luca Nicotra Prima edizione: maggio 2010 Universitalia INTRODUZIONE Introduzione Costantino Sigismondi L’edizione del convegno gerbertiano del 2009, in pieno anno internazionale dell’astronomia, si è tenuta nella Basilica di S. Maria degli Angeli e dei Martiri il 12 maggio, e a Seoul presso l’università Sejong l’11 giugno 2009. La scelta della Basilica è dovuta alla presenza della grande meridiana voluta dal papa Clemente XI Albani nel 1700, che ancora funziona e consente di fare misure di valore astrometrico. Il titolo di questi atti, ORBE NOVUS, è preso, come i precedenti, dall’epitaffio tombale di Silvestro II in Laterano, e vuole suggerire il legame con il “De Revolutionibus Orbium Coelestium” di Copernico, sebbene il contesto in cui queste parole sono tratte vuole inquadrare Gerberto nel suo ministero petrino come il nuovo pastore per tutto il mondo: UT FIERET PASTOR TOTO ORBE NOVVS. Elizabeth Cavicchi del Massachussets Institute of Technology, ha riflettuto sulle esperienze di ottica geometrica fatte da Gerberto con i tubi, nel contesto contemporaneo dello sviluppo dell’ottica nel mondo arabo con cui Gerberto era stato in contatto. -
Enthymema XXIII 2019 the Technê of Aratus' Leptê Acrostich
Enthymema XXIII 2019 The Technê of Aratus’ Leptê Acrostich Jan Kwapisz University of Warsaw Abstract – This paper sets out to re-approach the famous leptê acrostich in Aratus’ Phaenomena (783-87) by confronting it with other early Greek acrostichs and the discourse of technê and sophia, which has been shown to play an important role in a gamut of Greek literary texts, including texts very much relevant for the study of Aratus’ acrostich. In particular, there is a tantalizing connection between the acrostich in Aratus’ poem that poeticized Eudoxus’ astronomical work and the so- called Ars Eudoxi, a (pseudo-)Eudoxian acrostich sphragis from a second-century BC papyrus. Keywords – Aratus; Eudoxus; Ars Eudoxi; Acrostichs; Hellenistic Poetry; Technê; Sophia. Kwapisz, Jan. “The Technê of Aratus’ Leptê Acrostich.” Enthymema, no. XXIII, 2019, pp. 374-89. http://dx.doi.org/10.13130/2037-2426/11934 https://riviste.unimi.it/index.php/enthymema Creative Commons Attribution 4.0 Unported License ISSN 2037-2426 The Technê of Aratus’ Leptê Acrostich* Jan Kwapisz University of Warsaw To the memory of Cristiano Castelletti (1971-2017) Λεπτὴ μὲν καθαρή τε περὶ τρίτον ἦμαρ ἐοῦσα εὔδιός κ’ εἴη, λεπτὴ δὲ καὶ εὖ μάλ’ ἐρευθὴς πνευματίη· παχίων δὲ καὶ ἀμβλείῃσι κεραίαις 785 τέτρατον ἐκ τριτάτοιο φόως ἀμενηνὸν ἔχουσα ἠὲ νότου ἀμβλύνετ’ ἢ ὕδατος ἐγγὺς ἐόντος. (Arat. 783-87) If [the Moon is] slender and clear about the third day, she will bode fair weather; if slender and very red, wind; if the crescent is thickish, with blunted horns, having a feeble fourth-day light after the third day, either it is blurred by a southerly or because rain is in the offing. -
The Dunhuang Chinese Sky: a Comprehensive Study of the Oldest Known Star Atlas
25/02/09JAHH/v4 1 THE DUNHUANG CHINESE SKY: A COMPREHENSIVE STUDY OF THE OLDEST KNOWN STAR ATLAS JEAN-MARC BONNET-BIDAUD Commissariat à l’Energie Atomique ,Centre de Saclay, F-91191 Gif-sur-Yvette, France E-mail: [email protected] FRANÇOISE PRADERIE Observatoire de Paris, 61 Avenue de l’Observatoire, F- 75014 Paris, France E-mail: [email protected] and SUSAN WHITFIELD The British Library, 96 Euston Road, London NW1 2DB, UK E-mail: [email protected] Abstract: This paper presents an analysis of the star atlas included in the medieval Chinese manuscript (Or.8210/S.3326), discovered in 1907 by the archaeologist Aurel Stein at the Silk Road town of Dunhuang and now held in the British Library. Although partially studied by a few Chinese scholars, it has never been fully displayed and discussed in the Western world. This set of sky maps (12 hour angle maps in quasi-cylindrical projection and a circumpolar map in azimuthal projection), displaying the full sky visible from the Northern hemisphere, is up to now the oldest complete preserved star atlas from any civilisation. It is also the first known pictorial representation of the quasi-totality of the Chinese constellations. This paper describes the history of the physical object – a roll of thin paper drawn with ink. We analyse the stellar content of each map (1339 stars, 257 asterisms) and the texts associated with the maps. We establish the precision with which the maps are drawn (1.5 to 4° for the brightest stars) and examine the type of projections used. -
The Hummel Planetarium Experience
THE HUMMEL PLANETARIUM | EXPERIENCE About us: The Arnim D. Hummel Planetarium has been nestled on the south side of Eastern Kentucky University’s campus since 1988. Since then, we have provided informal science education programs to EKU students, P-12 students, as well as the community. The main theme of our programs are seated in the fields of physics and astronomy, but recent programs have explored a myriad of STEM related topics through engaging hands on experiences. Who can visit and when? We are open to the public during select weekday afternoons and evenings (seasonal) as well as most Saturdays throughout the year. The public show schedule is pre-set, and the programs serve audiences from preschool age and up. We also welcome private reservations for groups of twenty or more Mondays through Fridays during regular business hours. Examples of groups who reserve a spot include school field trips, homeschool groups, church groups, summer camps, and many more. When booking a private reservation, your group may choose which show to watch, and request a customized star talk, if needed. What happens during a visit? Most visits to the Planetarium involve viewing a pre-recorded show which is immediately followed by a live Star Talk presentation inside of the theater. A planetarium theater is unique because the viewing area is rounded into the shape of a dome instead of a flat, two-dimensional screen. The third dimension enables you, the viewer, to become immersed in the scenes displayed on the dome. A list of the pre-recorded shows we offer is found on the next page. -
Read Book the Atlas
THE ATLAS PDF, EPUB, EBOOK William T. Vollmann | 496 pages | 01 Jun 1997 | Penguin Books Australia | 9780140254495 | English | Hawthorn, Australia The Atlas PDF Book For a collection of maps, see atlas. For Atlas had worked out the science of astrology to a degree surpassing others and had ingeniously discovered the spherical nature of the stars, and for that reason was generally believed to be bearing the entire firmament upon his shoulders. On the Customize screen turn off the Use default mobile theme option under Advanced Options. Although Paloma was very young, she was a very happy and dedicated mother. Ancient Greek deities by affiliation. In addition to presenting geographic features and political boundaries, many atlases often feature geopolitical , social, religious and economic statistics. Unsourced material may be challenged and removed. Selected Weekly Fruit Movement and Price describes the change in shipment volume, farm prices, and retail prices of select fruit for the week noted. The people behind the movement. Namespaces Article Talk. Police never caught them, although the street was surveyed by video cameras. It provides fascinating insights into the world of politics, art, education, foreign policy, science, and more, rewarding you with a rich understanding of how ideas shape your world. October 20, AM Fruit and Tree Nuts Data Fruit and Tree Nuts Data provide users with comprehensive statistics on fresh and processed fruits, melons, and tree nuts in the United States, as well as some global data for these sectors. One is for sure the food. Examine the aspirations, arguments, strategies, and disasters of socialist theory and practice. -
History of Astronomy Is a History of Receding Horizons.”
UNA Planetarium Image of the Month Newsletter Vol. 2. No. 9 Sept 15, 2010 We are planning to offer some exciting events this fall, including a return of the laser shows. Our Fall Laser Shows will feature images and music of Led Zeppelin and Pink Floyd. The word laser is actually an acronym for Light Amplification by Stimulated Emission of Radiation”. We use many devices with lasers in them, from CD players to the mouse on your desk. What many people don’t know is that there are also natural lasers in space. The lasers in space often come from molecules (groups of one or more atoms sharing electrons); we call these masers. One of the more important one is the OH In 1987, astronomers observing from Chile observed a new star in the sky. This maser, formed by an oxygen and hydrogen exploding star, called a supernova, blazed away as the first supernova in several atom. The conditions in dense clouds that hundred years that was visible without a telescope. Ever since the Hubble Space form stars supply the requirements for telescope has been observing the ejecta of the explosion traveling through its host these masers. Radio astronomers study galaxy, called the Large Magellanic Cloud. This recent image of the exploding star these masers coming and going in these shows a 6-trillion mile diameter gas ring ejected from the star thousands of years dense clouds and even rotating around in before the explosion. Stars that will explode become unstable and lose mass into disks near their stars. This gives space, resulting in such rings. -
Abd Al-Rahman Al-Sufi and His Book of the Fixed Stars: a Journey of Re-Discovery
ResearchOnline@JCU This file is part of the following reference: Hafez, Ihsan (2010) Abd al-Rahman al-Sufi and his book of the fixed stars: a journey of re-discovery. PhD thesis, James Cook University. Access to this file is available from: http://eprints.jcu.edu.au/28854/ The author has certified to JCU that they have made a reasonable effort to gain permission and acknowledge the owner of any third party copyright material included in this document. If you believe that this is not the case, please contact [email protected] and quote http://eprints.jcu.edu.au/28854/ 5.1 Extant Manuscripts of al-Ṣūfī’s Book Al-Ṣūfī’s ‘Book of the Fixed Stars’ dating from around A.D. 964, is one of the most important medieval Arabic treatises on astronomy. This major work contains an extensive star catalogue, which lists star co-ordinates and magnitude estimates, as well as detailed star charts. Other topics include descriptions of nebulae and Arabic folk astronomy. As I mentioned before, al-Ṣūfī’s work was first translated into Persian by al-Ṭūsī. It was also translated into Spanish in the 13th century during the reign of King Alfonso X. The introductory chapter of al-Ṣūfī’s work was first translated into French by J.J.A. Caussin de Parceval in 1831. However in 1874 it was entirely translated into French again by Hans Karl Frederik Schjellerup, whose work became the main reference used by most modern astronomical historians. In 1956 al-Ṣūfī’s Book of the fixed stars was printed in its original Arabic language in Hyderabad (India) by Dārat al-Ma‘aref al-‘Uthmānīa. -
Sun, Moon, and Stars
Teacher's Guide for: Sun, Moon, and Stars OBJECTIVES: To introduce the planetarium and the night sky to the young learner. To determine what things we receive from the Sun. To see that the other stars are like our Sun, but farther away. To observe why the Moon appears to change shape and "visit" the Moon to see how it is different from the Earth. To observe the Earth from space and see that it really moves, despite the fact it looks like the Sun and stars are moving. This show conforms to the following Illinois state science standards: 12.F.1a, 12.F.1b, 12.F.2a, 12.F.2b, 12.F.2c, 12.F.3a, 12.F.3b. Next Generation Science Standards: 1.ESS1.1, 5PS2.1 BRIEF SHOW DESCRIPTION: "Sun, Moon, & Stars" is a live show for the youngest stargazers. We do a lot of pretending in the show, first by seeing what the Sun might look like both up close and from far away, and then taking an imaginary adventure to the Moon. We see the changing Moon in the sky and see how the stars in the sky make strange shapes when you connect them together. The planets can be inserted at the request of the instructor. PRE-VISIT ACTIVITIES/TOPICS FOR DISCUSSION: For the young ones, just being in the planetarium is a different experience they should "prepare" for. Discuss what it's like in a movie theater with the lights low. That's how we introduce the place. The screen goes all the way around though! Discuss the importance of the Sun. -
The Planetarium Environment by Kevin Scott the Experience of A
The Planetarium Environment by Kevin Scott The experience of a planetarium audience and staff is greatly affected by the basic physical infrastructure of a planetarium. Attention to detail in this realm is vital to a new planetarium construction project. Electrical Power Local building codes will provide a baseline for your particular power scheme and a licensed electrical engineer will handle much of the design work. Even so, it’s probably a good idea to be involved with the design process and familiarize yourself with the electrical requirements of your theater. Your interpretation of the space and production philosophy will dictate many aspects of the electrical layout and capacity. Every planetarium will have some form of star projector, and quite often there will be other unique equipment with special electrical requirements including laser systems, lighting instruments, projector lifts, and high concentrations of audio-visual equipment. Conduits and raceways for all of these devices will have to be mapped out. A spacious electrical room will make it easy to cleanly route power and control wiring throughout the planetarium. This master control area should be centrally located, perhaps beneath the theater to avoid any noise problems from equipment fans or lighting dimmers. A raised floor is an added luxury, but can make equipment installation and maintenance a breeze. Your electrical contractor will probably provide raceways for any automation control wiring. These control signals are mostly low-voltage and will need to be housed in raceways and conduits separate from power delivery. Keep in mind that you’ll want to have easy access to your low-voltage raceways for future equipment additions and upgrades. -
The Baader Planetarium
1 THE BAADER PLANETARIUM INSTRUCTION MANUAL BAADER PLANETARIUM Zur Sternwarte M 82291 Mammendorf M Tel. 08145/8802 M Fax 08145/8805 www.baader-planetarium.de M [email protected] M www.celestron-deutschland.de 2 HINTS/TECHNICAL 1. YOUR PLANETARIUM OPERATES BY A DC MINIATUR MOTOR. IT'S LIFETIME IS THEREFORE LIMITED. PLEASE HAVE THE MOTOR USUALLY RUN IN THE SLOWEST SPEED POSSIBLE. FOR EXHIBITIONS OR PERMANENT DISPLAY A TIME LIMIT SWITCH IS A MUST. 2. DON'T HAVE THE SUNBULB WORKING IN THE HIGHEST STEP CONTINUOUSLY. THIS STEP IS FORSEEN ONLY FOR PROJECTING THE HEAVENS IF THE PLASTIC SUNCAP IS REMOVED. 3. CLOSE THE SPHERE AT ANY TIME POSSIBLE. HINTS/THEORETICAL 1. ESPECIALLY GIVE ATTENTION TO PAGE 5-3.F OF THE MANUAL. 2. CLOSE THE SPHERE SO THAT THE ORBIT LINES OF THE PLANETS INSIDE FIT CORRECTLY PAGE 6-5.A. 3. USUALLY DEMONSTRATE BY KEEPING THE EARTH'S ORBIT HORIZONTAL. 4. A SPECIAL EXPLANTATION FOR THE SEASONS IS POSSIBLE IF YOU TURN THE SPHERE TO A HORIZONTAL CELESTIAL EQUATOR. NOW THE EARTH MOVES UP AND DOWN ON ITS WAY AROUND THE SUN. MENTION THE APPEARING LIGHTPHASES. 5. REMEMBER THE GREATEST FINDING OF COPERNICUS: THE DISTANCE EARTH - SUN IS NEARLY ZERO COMPARED TO THE DISTANCE OF THE FIXED STARS. IN REALITY THE WHOLE SOLAR SYSTEM IN THE CELESTIAL SPHERE WOULD BE A PINPOINT IN THE CENTER. THIS HELPS TO UNDERSTAND THE MINUTE STELLAR PARALLAXE AND THE "FIXED" POSITION OF THE STARS COMPARED TO THE SUN'S CHANGING HEIGHT OVER THE HORIZON DURING THE YEAR. 3 INTRODUCTION For countless centuries the stars have been objects of mystery. -
The Dark Shades of the Antikythera Mechanism
Journal of Radioanalytical and Nuclear Chemistry https://doi.org/10.1007/s10967-018-6255-9 (0123456789().,-volV)(0123456789().,-volV) The dark shades of the Antikythera Mechanism 1 2 3 Aristeidis Voulgaris • Christophoros Mouratidis • Andreas Vossinakis Received: 19 June 2018 Ó Akade´miai Kiado´, Budapest, Hungary 2018 Abstract In this work we analyze the dark shades which are evident on the AMRP X-ray positive Computed Tomographies and Radiographies of the Antikythera Mechanism ancient prototype. During 2000 years under the sea, the Mechanism bronze parts were totally corroded. The decreased X-ray absorption of the corroded bronze, allowed the CTs capture even in the thick large side of Fragment A. During the photometric analysis of the CTs, apart from corroded bronze, at least two other different (corroded) metal materials were detected, which were used by the ancient manufacturer during the construction of the Antikythera Mechanism. From our analysis and correlating with the mechanical evidence resulting by the use of our functional reconstruction models of the Antikythera Mechanism, we conclude that the existing design of the Antikythera Mechanism is probably the first of such a sophisticated design of the ancient manufacturer. Keywords Metals of Antikythera Mechanism Á Bronze corrosion Á Atacamite X-ray absorption Introduction Mechanism via the 2D X-ray and Thulium 170 radiation began by C. Karakalos of National Centre of Scientific The Antikythera Mechanism was found in 1901, in a Research ‘‘Demokritos’’ (Greece), in the 1970s. Karakalos shipwreck at 50 m depth, on a gulf of Antikythera island, took several film radiographies @160 keV [3]. The first Greece, by Symian sponge divers. -
Models for Earth and Maps
Earth Models and Maps James R. Clynch, Naval Postgraduate School, 2002 I. Earth Models Maps are just a model of the world, or a small part of it. This is true if the model is a globe of the entire world, a paper chart of a harbor or a digital database of streets in San Francisco. A model of the earth is needed to convert measurements made on the curved earth to maps or databases. Each model has advantages and disadvantages. Each is usually in error at some level of accuracy. Some of these error are due to the nature of the model, not the measurements used to make the model. Three are three common models of the earth, the spherical (or globe) model, the ellipsoidal model, and the real earth model. The spherical model is the form encountered in elementary discussions. It is quite good for some approximations. The world is approximately a sphere. The sphere is the shape that minimizes the potential energy of the gravitational attraction of all the little mass elements for each other. The direction of gravity is toward the center of the earth. This is how we define down. It is the direction that a string takes when a weight is at one end - that is a plumb bob. A spirit level will define the horizontal which is perpendicular to up-down. The ellipsoidal model is a better representation of the earth because the earth rotates. This generates other forces on the mass elements and distorts the shape. The minimum energy form is now an ellipse rotated about the polar axis.