Unit 2 Basic Concepts of Positional Astronomy
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The Lore of the Stars, for Amateur Campfire Sages
obscure. Various claims have been made about Babylonian innovations and the similarity between the Greek zodiac and the stories, dating from the third millennium BCE, of Gilgamesh, a legendary Sumerian hero who encountered animals and characters similar to those of the zodiac. Some of the Babylonian constellations may have been popularized in the Greek world through the conquest of The Lore of the Stars, Alexander in the fourth century BCE. Alexander himself sent captured Babylonian texts back For Amateur Campfire Sages to Greece for his tutor Aristotle to interpret. Even earlier than this, Babylonian astronomy by Anders Hove would have been familiar to the Persians, who July 2002 occupied Greece several centuries before Alexander’s day. Although we may properly credit the Greeks with completing the Babylonian work, it is clear that the Babylonians did develop some of the symbols and constellations later adopted by the Greeks for their zodiac. Contrary to the story of the star-counter in Le Petit Prince, there aren’t unnumerable stars Cuneiform tablets using symbols similar to in the night sky, at least so far as we can see those used later for constellations may have with our own eyes. Only about a thousand are some relationship to astronomy, or they may visible. Almost all have names or Greek letter not. Far more tantalizing are the various designations as part of constellations that any- cuneiform tablets outlining astronomical one can learn to recognize. observations used by the Babylonians for Modern astronomers have divided the sky tracking the moon and developing a calendar. into 88 constellations, many of them fictitious— One of these is the MUL.APIN, which describes that is, they cover sky area, but contain no vis- the stars along the paths of the moon and ible stars. -
Exercise 3.0 the CELESTIAL HORIZON SYSTEM
Exercise 3.0 THE CELESTIAL HORIZON SYSTEM I. Introduction When we stand at most locations on the Earth, we have the distinct impression that the Earth is flat. This occurs because the curvature of the small area of the Earth usually visible is very slight. We call this “flat Earth” the Plane of the Horizon and divide it up into 4 quadrants, each containing 90o, by using the cardinal points of the compass. The latter are the North, South, East, and west points of the horizon. We describe things as being vertical or “straight up” if they line up with the direction of gravity at that location. It is easy for us to determine “straight up” because we have a built in mechanism for this in the inner ear (the semicircular canals). Because it seems so “natural”, we build a coordinate system on these ideas called the Horizon System. The Celestial Horizon System is one of the coordinate systems that astronomers find useful for locating objects in the sky. It is depicted in the Figure below. Figure 1. The above diagram is a skewed perspective, schematic diagram of the celestial sphere with circles drawn only for the half above the horizon. Circles on the far side, or western half, of the celestial sphere are drawn as dashed curves. All the reference circles of this system do not share in the rotation of the celestial sphere and, therefore, this coordinate system is fixed with respect to a given observer. The basis for the system is the direction of gravity. We can describe this as the line from the observer on the surface of the Earth through the center of the Earth. -
Review for Astronomy 5 Midterm and Final Midterm Covers First 70 Questions, Final Covers All 105
Review for Astronomy 5 Midterm and Final Midterm covers first 70 questions, Final covers all 105. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Chapter 1 is covered by Q1-4; Ch. 2 Q5-13; Ch. 3 Q14-21; Ch. 4 Q22-28; Ch. 5 Q29-38; Ch. 6 Q39-43; Ch. 14 Q44-49; Ch. 15 Q50-60; Ch. 16 Q61-65; Ch. 17 Q66-73; Ch. 18 Q74-82; Ch. 19 Q83-87; Ch. 20 Q88-94; Ch. 21 Q95-96; Ch. 22 Q97-100; Ch. 23 Q101-105 1) Which of the following has your "address" in the correct order? A) you, Earth, solar system, Milky Way, Local Group, Local Supercluster B) you, Earth, solar system, Local Group, Milky Way, Local Supercluster C) you, Earth, solar system, Local Group, Local Supercluster, Milky Way D) you, Earth, Local Group, Local Supercluster, solar system, Milky Way E) you, Earth, solar system, Milky Way, Local Supercluster, Local Group 2) Roughly how many stars are in the Milky Way Galaxy? A) 10 billion B) 1 billion C) 100 million D) 100 trillion E) 100 billion 3) Which scientists played a major role in overturning the ancient idea of an Earth-centered universe, and about when? A) Aristotle and Copernicus; about 400 years ago B) Huygens and Newton; about 300 years ago C) Copernicus, Kepler, and Galileo; about 400 years ago D) Newton and Einstein; about 100 years ago E) Aristotle and Plato; about 2,000 years ago 4) What is an astronomical unit? A) the average distance from Earth to the Sun B) any basic unit used in astronomy C) the length of time it takes Earth to revolve around the Sun D) the average speed of Earth around the Sun E) the diameter of Earth's orbit around the Sun 5) Which of the following statements about the celestial sphere is not true? A) The celestial sphere does not exist physically. -
The 1994 Arctic Ocean Section the First Major Scientific Crossing of the Arctic Ocean 1994 Arctic Ocean Section
The 1994 Arctic Ocean Section The First Major Scientific Crossing of the Arctic Ocean 1994 Arctic Ocean Section — Historic Firsts — • First U.S. and Canadian surface ships to reach the North Pole • First surface ship crossing of the Arctic Ocean via the North Pole • First circumnavigation of North America and Greenland by surface ships • Northernmost rendezvous of three surface ships from the largest Arctic nations—Russia, the U.S. and Canada—at 89°41′N, 011°24′E on August 23, 1994 — Significant Scientific Findings — • Uncharted seamount discovered near 85°50′N, 166°00′E • Atlantic layer of the Arctic Ocean found to be 0.5–1°C warmer than prior to 1993 • Large eddy of cold fresh shelf water found centered at 1000 m on the periphery of the Makarov Basin • Sediment observed on the ice from the Chukchi Sea to the North Pole • Biological productivity estimated to be ten times greater than previous estimates • Active microbial community found, indicating that bacteria and protists are significant con- sumers of plant production • Mesozooplankton biomass found to increase with latitude • Benthic macrofauna found to be abundant, with populations higher in the Amerasia Basin than in the Eurasian Basin • Furthest north polar bear on record captured and tagged (84°15′N) • Demonstrated the presence of polar bears and ringed seals across the Arctic Basin • Sources of ice-rafted detritus in seafloor cores traced, suggesting that ocean–ice circulation in the western Canada Basin was toward Fram Strait during glacial intervals, contrary to the present -
The Distant Early Warning (DEW) Line: a Bibliography and Documentary Resource List
The Distant Early Warning (DEW) Line: A Bibliography and Documentary Resource List Prepared for the Arctic Institute of North America By: P. Whitney Lackenbauer, Ph.D. Matthew J. Farish, Ph.D. Jennifer Arthur-Lackenbauer, M.Sc. October 2005 © 2005 The Arctic Institute of North America ISBN 1-894788-01-X The DEW Line: Bibliography and Documentary Resource List 1 TABLE OF CONTENTS 1.0 PREFACE 2 2.0 BACKGROUND DOCUMENTS 3 2.1 Exchange of Notes (May 5, 1955) Between Canada and the United States Of America Governing the Establishment of a Distant Early Warning System in Canadian Territory.......................................................................................................... 3 2.2 The DEW Line Story in Brief (Western Electric Corporation, c.1960) ……………… 9 2.3 List of DEW Line Sites ……………………………………….…………………….... 16 3.0 ARCHIVAL COLLECTIONS 23 3.1 Rt. Hon. John George Diefenbaker Centre ……………………………………….…... 23 3.2 Library and Archives Canada …………………………………….…………………... 26 3.3 Department of National Defence, Directorate of History and Heritage ………………. 46 3.4 NWT Archives Council, Prince of Wales Northern Heritage Centre ……………….... 63 3.5 Yukon Territorial Archives, Whitehorse, YT ………………………………………… 79 3.6 Hudson Bay Company Archives ……………………………………………………... 88 3.7 Archives in the United States ……………………………………………………….… 89 4.0 PUBLISHED SOURCES 90 4.1 The Globe and Mail …………………………………………………………………………… 90 4.2 The Financial Post ………………………………………………………………………….…. 99 4.3 Other Print Media …………………………………………………………………..… 99 4.4 Contemporary Journal Articles ……………………………………………………..… 100 4.5 Government Publications …………………………………………………………….. 101 4.6 Corporate Histories ………………………………………………………………...... 103 4.7 Professional Journal Articles ………………………………………………………..… 104 4.8 Books ………………………………………………………………………………..… 106 4.9 Scholarly and Popular Articles ………………………………………………….……. 113 4.10 Environmental Issues and Cleanup: Technical Reports and Articles …………….…. 117 5.0 OTHER SOURCES 120 5.1 Theses and Dissertations ……………………………………………………………... -
Field Astronomy Circumpolar Star at Elongation ➢ at Elongation a Circumpolar Star Is at the Farthest Position from the Pole Either in the East Or West
Field Astronomy Circumpolar Star at Elongation ➢ At elongation a circumpolar star is at the farthest position from the pole either in the east or west. ➢ When the star is at elongation (East or West), which is perpendicular to the N-S line. ➢ Thus the ZMP is 90° as shown in the figure below. Distances between two points on the Earth’s surface ➢ Direct distance From the fig. above, in the spherical triangle APB P = Difference between longitudes of A and B BP = a = co-latitude of B = 90 – latitude of B AP = b = co-latitude of A = 90 – latitude of A Apply the cosine rule: cosp− cos a cos b CosP = sinab sin Find the value of p = AB Then the distance AB = arc length AB = ‘p’ in radians × radius of the earth ➢ Distance between two points on a parallel of latitude Let A and B be the two points on the parallel latitude θ. Let A’ and B’ be the corresponding points on the equator having the same longitudes (ФB, ФA). Thus from the ∆ O’AB AB = O’B(ФB - ФA) From the ∆ O’BO o O’B = OB’ sin (90- θ) Since =BOO ' 90 = R cos θ where R=Radius of the Earth. AB= (ФB - ФA) R cos θ where ФB , ФA are longitudes of B and A in radians. Practice Problems 1. Find the shortest distance between two places A and B on the earth for the data given below: Latitude of A = 14° N Longitude of A = 60°30‘E Latitude of B = 12° N Longitude of A = 65° E Find also direction of B from A. -
Introduction to Astronomy Introduction
IDP HOME CONTENTS NEXT: Introduction to Astronomy Introduction For many thousands of years, man has attempted to make sense of the sky by naming and grouping stars into recognisable patterns. At the turn of the twentieth century, Marc Aurel Stein, a Hungarian- born, British archaeologist uncovered the world’s oldest existing star chart in a Buddhist cave complex in Dunhuang, China. The chart, now known as the Dunhuang Star Atlas and probably dating from before AD 700, was just one of a large number of important manuscripts, printed documents and paintings which were found at the site, and which tell us much about social, religious and political issues in medieval China and Central Asia. But the Star Atlas – now held at the British Library in London – is also proving important for our current understanding of astronomical history due to the accuracy and detail it provides about the sky seen from China from such an early period. This resource aims to: Introduce the Dunhuang Star Atlas and explain its importance as a historical and scientific document Offer an introduction to astronomy and explain the place it has occupied in Chinese history and culture. Introduce the most important Chinese constellations and the myths associated with them. Look at the links between Chinese astronomy and astrology and explore the Chinese ‘zodiac’. Offer ideas for classroom activities and downloadable resources for teachers. Link to related websites and other sources of information. IDP HOME CONTENTS NEXT: Introduction to Astronomy file:///Users/bobi/PC/Documents_PC/wintext/chine/dunhuang/BLib... 1 sur 1 IDP HOME CONTENTS PREVIOUS: Introduction to this Resource NEXT: History of Astronomy in China Introduction to Astronomy For thousands of years, man has used the sky to help him find his way, tell the change of season and the time of day. -
Public Naming of Exoplanets and Their Stars: Implementation and Outcomes of the IAU100
Public Naming of Exoplanets and Their Stars: Implementation and Outcomes of the IAU100 Best Practice Best NameExoWorlds Global Project Eric Mamajek Debra Meloy Elmegreen Alain Lecavelier des Etangs Jet Propulsion Laboratory, California Vassar College Institut d’Astrophysique de Paris Institute of Technology [email protected] [email protected] [email protected] Eduardo Monfardini Penteado Lars Lindberg Christensen [email protected] NSF’s NOIRLab [email protected] Gareth Williams [email protected] Hitoshi Yamaoka National Astronomical Observatory of Guillem Anglada-Escudé Japan (NAOJ) Institute for Space Science (ICE/CSIC), [email protected] Queen Mary University of London Keywords [email protected] exoplanets, IAU nomenclature The IAU100 NameExoWorlds public naming campaign was a core project during the International Astronomical Union’s 100th anniversary (IAU100) in 2019, giving the opportunity to everyone, everywhere, to propose official names for exoplanets and their host stars. With IAU100 NameExoWorlds the IAU encouraged all peoples of Earth to consider themselves as “Citizens of the Universe”, united “under one sky”. The 113 national campaigns involved hundreds of thousands of people in a global effort to bring the public closer to science by allowing them to participate in the process of naming stars and planets, and learning more about astronomy in the process. The campaign resulted in nearly 425 000 votes, and 113 new IAU-recognised proper names for exoplanets and 113 new names for their stars. The IAU now officially recognises the chosen proper names in addition to their previous scientific designations, and they appear in popular databases. Introduction wished to contribute to the fraternity of all through international cooperation, the IAU people with a significant token of global is the authority responsible for assigning Over the past three decades, astronomers identity. -
Chasing the Pole — Howard L. Cohen
Reprinted From AAC Newsletter FirstLight (2010 May/June) Chasing the Pole — Howard L. Cohen Polaris like supernal beacon burns, a pivot-gem amid our star-lit Dome ~ Charles Never Holmes (1916) ew star gazers often believe the North Star (Polaris) is brightest of all, even mistaking Venus for this best known star. More advanced star gazers soon learn dozens of Nnighttime gems appear brighter, forty-seven in fact. Polaris only shines at magnitude +2.0 and can even be difficult to see in light polluted skies. On the other hand, Sirius, brightest of all nighttime stars (at magnitude -1.4), shines twenty-five times brighter! Beginning star gazers also often believe this guidepost star faithfully defines the direction north. Although other stars staunchly circle the heavens during night’s darkness, many think this pole star remains steadfast in its position always marking a fixed point on the sky. Indeed, a popular and often used Shakespeare quote (from Julius Caesar) is in tune with this perception: “I am constant as the northern star, Of whose true-fix'd and resting quality There is no fellow in the firmament.” More advanced star gazers know better, that the “true-fix’d and resting quality”of the northern star is only an approximation. Not only does this north star slowly circle the northen heavenly pole (Fig. 1) but this famous star is also not quite constant in light, slightly varying about 0.03 magnitudes. Polaris, in fact, is the brightest appearing Cepheid variable, a type of pulsating star. Still, Polaris is a good marker of the north cardinal point. -
Astronomy 113 Laboratory Manual
UNIVERSITY OF WISCONSIN - MADISON Department of Astronomy Astronomy 113 Laboratory Manual Fall 2011 Professor: Snezana Stanimirovic 4514 Sterling Hall [email protected] TA: Natalie Gosnell 6283B Chamberlin Hall [email protected] 1 2 Contents Introduction 1 Celestial Rhythms: An Introduction to the Sky 2 The Moons of Jupiter 3 Telescopes 4 The Distances to the Stars 5 The Sun 6 Spectral Classification 7 The Universe circa 1900 8 The Expansion of the Universe 3 ASTRONOMY 113 Laboratory Introduction Astronomy 113 is a hands-on tour of the visible universe through computer simulated and experimental exploration. During the 14 lab sessions, we will encounter objects located in our own solar system, stars filling the Milky Way, and objects located much further away in the far reaches of space. Astronomy is an observational science, as opposed to most of the rest of physics, which is experimental in nature. Astronomers cannot create a star in the lab and study it, walk around it, change it, or explode it. Astronomers can only observe the sky as it is, and from their observations deduce models of the universe and its contents. They cannot ever repeat the same experiment twice with exactly the same parameters and conditions. Remember this as the universe is laid out before you in Astronomy 113 – the story always begins with only points of light in the sky. From this perspective, our understanding of the universe is truly one of the greatest intellectual challenges and achievements of mankind. The exploration of the universe is also a lot of fun, an experience that is largely missed sitting in a lecture hall or doing homework. -
Celestial Sphere
ASTR 111 – 003 Fall 2007 Lecture 02 Sep. 10, 2007 Introduction To Modern Astronomy I: Solar System Ch1: Astronomy and the Universe Introducing Astronomy (chap. 1-6) Ch2: Knowing the Heavens Ch3: Eclipses and the Motion of the Moon Planets and Moons (chap. 7-15) Ch4: Gravitation and the Waltz of the Planets Ch5: The Nature of Light Chap. 16: Our Sun Ch6: Optics and Telescope Chap. 28: Search for Extraterrestrial life Knowing the Heavens Chapter Two Hawaii: N20° Washington D.C.: N38° Positional Astronomy • Positional astronomy – the study of the positions of objects in the sky and how these positions change • It has roots in almost all ancient civilizations • Naked-eye astronomy – the sort that requires only human vision (no telescope) The Sun Dagger at Chaco Canyon, New Mexico Positional Astronomy • Position of stars in the heaven; forming consternations • Path of Sun, Moon and Planets; forming zodiac band Heaven’s Sphere at Purple Mountain Observatory, Nanjing, China Constellations From the Latin for “group of stars” ORION: Photograph Modern Star Atlas Ancient Star Atlas(1835) ORION (the Hunter) Betelgeuse: the armpit; Mintaka: the belt Constellations •Zodiac Constellations: 12 in total along the ecliptic path Constellations • On modern star charts, the entire sky is divided into 88 constellations • Starts in the same constellation only appear to be close, because they are in nearly the same direction as seen from Earth • However, most stars in a constellation are nowhere near one another in real 3-D distance. North Star: Polaris •Visible -
Astr 1050 Wed. Jan. 28, 2015
Astr 1050 Wed. Jan. 28, 2015 • Begin Chapter 2 topics – The Celestial Sphere – Moon Phases – Eclipses – Planetary Motion Reading: For Today: Begin Chapter 2 For Friday: Finish Chapter 3 Ch. 2 Homework on Mastering Astronomy (Due Next Monday) Chapter 2: The View From The Earth • Imagine being in a rotating restaurant on top of a tall building. All the outside objects are very far away – much farther than the distance across the room. • Paint the view on the windows – and keep the people near the center of the room – away from the windows themselves. • Can the people tell if the room is rotating, or if the painted windows are just moving around the room? • Which is more reasonable – a rotating room or rotating painted windows? The Canada National Tower in Toronto Celestial Sphere Nomenclature • HORIZON: The horizontal circle which separates the part of the sky visible to you and the part of the sky hidden by the earth. • ZENITH: The point on the sky directly overhead. • MERIDIAN: The circle which starts on the northern horizon, runs through the zenith, continuing on to the southern horizon. It separates the eastern half of the sky from the western half. • CELESTIAL POLES: The points where the extension of the rotation axis of the earth would intersect the celestial sphere. • CELESTIAL EQUATOR: The circle around the sky which would be a projection of the earth’s equator. Limiting Cases From Voyages through the Universe, by Fraknoi et al. – At the Earth’s north pole, looking overhead all stars appear to circle around the north celestial pole.