Chapter 16 Time
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Changing Time: Possible Effects on Peak Electricity Generation
A Service of Leibniz-Informationszentrum econstor Wirtschaft Leibniz Information Centre Make Your Publications Visible. zbw for Economics Crowley, Sara; FitzGerald, John; Malaguzzi Valeri, Laura Working Paper Changing time: Possible effects on peak electricity generation ESRI Working Paper, No. 486 Provided in Cooperation with: The Economic and Social Research Institute (ESRI), Dublin Suggested Citation: Crowley, Sara; FitzGerald, John; Malaguzzi Valeri, Laura (2014) : Changing time: Possible effects on peak electricity generation, ESRI Working Paper, No. 486, The Economic and Social Research Institute (ESRI), Dublin This Version is available at: http://hdl.handle.net/10419/129397 Standard-Nutzungsbedingungen: Terms of use: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Documents in EconStor may be saved and copied for your Zwecken und zum Privatgebrauch gespeichert und kopiert werden. personal and scholarly purposes. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle You are not to copy documents for public or commercial Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich purposes, to exhibit the documents publicly, to make them machen, vertreiben oder anderweitig nutzen. publicly available on the internet, or to distribute or otherwise use the documents in public. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, If the documents have been made available under an Open gelten abweichend von diesen Nutzungsbedingungen -
Planet Positions: 1 Planet Positions
Planet Positions: 1 Planet Positions As the planets orbit the Sun, they move around the celestial sphere, staying close to the plane of the ecliptic. As seen from the Earth, the angle between the Sun and a planet -- called the elongation -- constantly changes. We can identify a few special configurations of the planets -- those positions where the elongation is particularly noteworthy. The inferior planets -- those which orbit closer INFERIOR PLANETS to the Sun than Earth does -- have configurations as shown: SC At both superior conjunction (SC) and inferior conjunction (IC), the planet is in line with the Earth and Sun and has an elongation of 0°. At greatest elongation, the planet reaches its IC maximum separation from the Sun, a value GEE GWE dependent on the size of the planet's orbit. At greatest eastern elongation (GEE), the planet lies east of the Sun and trails it across the sky, while at greatest western elongation (GWE), the planet lies west of the Sun, leading it across the sky. Best viewing for inferior planets is generally at greatest elongation, when the planet is as far from SUPERIOR PLANETS the Sun as it can get and thus in the darkest sky possible. C The superior planets -- those orbiting outside of Earth's orbit -- have configurations as shown: A planet at conjunction (C) is lined up with the Sun and has an elongation of 0°, while a planet at opposition (O) lies in the opposite direction from the Sun, at an elongation of 180°. EQ WQ Planets at quadrature have elongations of 90°. -
TYPHOONS and DEPRESSIONS OVER the FAR EAST Morning Observation, Sep Teinber 6, from Rasa Jima Island by BERNARDF
SEPTEMBER1940 MONTHLY WEATHER REVIEW 257 days west of the 180th meridian. In American coastal appear to be independent of the typhoon of August 28- waters fog was noted on 10 days each off Washington and September 5, are the following: The S. S. Steel Exporter California; on 4 days off Oregon; and on 3 days off Lower reported 0700 G. C. T. September 6, from latitude 20'18' California. N., longitude 129'30'E.) a pressure of 744.8 mm. (993.0 nib.) with west-northwest winds of force 9. Also, the TYPHOONS AND DEPRESSIONS OVER THE FAR EAST morning observation, Sep teinber 6, from Rasa Jima Island By BERNARDF. DOUCETTE, J. (one of the Nansei Island group) was 747.8 mm. (997.0 5. mb.) for pressure and east-northeast, force 4, for winds. [Weather Bureau, Manila, P. I.] Typhoon, September 11-19) 1940.-A depression, moving Typhoon, August %!-September 6,1940.-A low-pressure westerly, passed about 200 miles south of Guam and area far to the southeast of Guam moved west-northwest, quickly inclined to the north, intensifying to typhoon rapidly developing to typhoon intensity as it proceeded. strength, September 11 to 13. It was stationary, Sep- When the center reached the regions about 250 miles tember 13 and 14, about 150 miles west-northwest of west of Guam, the direction changed to the northwest, Guam, and then began a northwesterly and northerly and the storm continued along this course until it reached course to the ocean regions about 300 miles west of the the latitude of southern Formosa. -
Captain Vancouver, Longitude Errors, 1792
Context: Captain Vancouver, longitude errors, 1792 Citation: Doe N.A., Captain Vancouver’s longitudes, 1792, Journal of Navigation, 48(3), pp.374-5, September 1995. Copyright restrictions: Please refer to Journal of Navigation for reproduction permission. Errors and omissions: None. Later references: None. Date posted: September 28, 2008. Author: Nick Doe, 1787 El Verano Drive, Gabriola, BC, Canada V0R 1X6 Phone: 250-247-7858, FAX: 250-247-7859 E-mail: [email protected] Captain Vancouver's Longitudes – 1792 Nicholas A. Doe (White Rock, B.C., Canada) 1. Introduction. Captain George Vancouver's survey of the North Pacific coast of America has been characterized as being among the most distinguished work of its kind ever done. For three summers, he and his men worked from dawn to dusk, exploring the many inlets of the coastal mountains, any one of which, according to the theoretical geographers of the time, might have provided a long-sought-for passage to the Atlantic Ocean. Vancouver returned to England in poor health,1 but with the help of his brother John, he managed to complete his charts and most of the book describing his voyage before he died in 1798.2 He was not popular with the British Establishment, and after his death, all of his notes and personal papers were lost, as were the logs and journals of several of his officers. Vancouver's voyage came at an interesting time of transition in the technology for determining longitude at sea.3 Even though he had died sixteen years earlier, John Harrison's long struggle to convince the Board of Longitude that marine chronometers were the answer was not quite over. -
Sun Tool Options
Sun Study Tools Sophomore Architecture Studio: Lighting Lecture 1: • Introduction to Daylight (part 1) • Survey of the Color Spectrum • Making Light • Controlling Light Lecture 2: • Daylight (part 2) • Design Tools to study Solar Design • Architectural Applications Lecture 3: • Light in Architecture • Lighting Design Strategies Sun Tool Options 1. Paper and Pencil 2. Build a Model 3. Use a Computer The first step to any of these options is to define…. Where is the site? 1 2 Sun Study Tools North Latitude and Longitude South Longitude Latitude Longitude Sun Study Tools North America Latitude 3 United States e ud tit La Sun Study Tools New York 72w 44n 42n Site Location The site location is specified by a latitude l and a longitude L. Latitudes and longitudes may be found in any standard atlas or almanac. Chart shows the latitudes and longitudes of some North American cities. Conventions used in expressing latitudes are: Positive = northern hemisphere Negative = southern hemisphere Conventions used in expressing longitudes are: Positive = west of prime meridian (Greenwich, United Kingdom) Latitude and Longitude of Some North American Cities Negative = east of prime meridian 4 Sun Study Tools Solar Path Suns Position The position of the sun is specified by the solar altitude and solar azimuth and is a function of site latitude, solar time, and solar declination. 5 Sun Study Tools Suns Position The rotation of the earth about its axis, as well as its revolution about the sun, produces an apparent motion of the sun with respect to any point on the altitude earth's surface. The position of the sun with respect to such a point is expressed in terms of two angles: azimuth The sun's position in terms of solar altitude (a ) and azimuth (a ) solar azimuth, which is the t s with respect to the cardinal points of the compass. -
Basic Principles of Celestial Navigation James A
Basic principles of celestial navigation James A. Van Allena) Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242 ͑Received 16 January 2004; accepted 10 June 2004͒ Celestial navigation is a technique for determining one’s geographic position by the observation of identified stars, identified planets, the Sun, and the Moon. This subject has a multitude of refinements which, although valuable to a professional navigator, tend to obscure the basic principles. I describe these principles, give an analytical solution of the classical two-star-sight problem without any dependence on prior knowledge of position, and include several examples. Some approximations and simplifications are made in the interest of clarity. © 2004 American Association of Physics Teachers. ͓DOI: 10.1119/1.1778391͔ I. INTRODUCTION longitude ⌳ is between 0° and 360°, although often it is convenient to take the longitude westward of the prime me- Celestial navigation is a technique for determining one’s ridian to be between 0° and Ϫ180°. The longitude of P also geographic position by the observation of identified stars, can be specified by the plane angle in the equatorial plane identified planets, the Sun, and the Moon. Its basic principles whose vertex is at O with one radial line through the point at are a combination of rudimentary astronomical knowledge 1–3 which the meridian through P intersects the equatorial plane and spherical trigonometry. and the other radial line through the point G at which the Anyone who has been on a ship that is remote from any prime meridian intersects the equatorial plane ͑see Fig. -
AIM: Latitude and Longitude
AIM: Latitude and Longitude Latitude lines run east/west but they measure north or south of the equator (0°) splitting the earth into the Northern Hemisphere and Southern Hemisphere. Latitude North Pole 90 80 Lines of 70 60 latitude are 50 numbered 40 30 from 0° at 20 Lines of [ 10 the equator latitude are 10 to 90° N.L. 20 numbered 30 at the North from 0° at 40 Pole. 50 the equator ] 60 to 90° S.L. 70 80 at the 90 South Pole. South Pole Latitude The North Pole is at 90° N 40° N is the 40° The equator is at 0° line of latitude north of the latitude. It is neither equator. north nor south. It is at the center 40° S is the 40° between line of latitude north and The South Pole is at 90° S south of the south. equator. Longitude Lines of longitude begin at the Prime Meridian. 60° W is the 60° E is the 60° line of 60° line of longitude west longitude of the Prime east of the W E Prime Meridian. Meridian. The Prime Meridian is located at 0°. It is neither east or west 180° N Longitude West Longitude West East Longitude North Pole W E PRIME MERIDIAN S Lines of longitude are numbered east from the Prime Meridian to the 180° line and west from the Prime Meridian to the 180° line. Prime Meridian The Prime Meridian (0°) and the 180° line split the earth into the Western Hemisphere and Eastern Hemisphere. Prime Meridian Western Eastern Hemisphere Hemisphere Places located east of the Prime Meridian have an east longitude (E) address. -
Celestial Navigation Tutorial
NavSoft’s CELESTIAL NAVIGATION TUTORIAL Contents Using a Sextant Altitude 2 The Concept Celestial Navigation Position Lines 3 Sight Calculations and Obtaining a Position 6 Correcting a Sextant Altitude Calculating the Bearing and Distance ABC and Sight Reduction Tables Obtaining a Position Line Combining Position Lines Corrections 10 Index Error Dip Refraction Temperature and Pressure Corrections to Refraction Semi Diameter Augmentation of the Moon’s Semi-Diameter Parallax Reduction of the Moon’s Horizontal Parallax Examples Nautical Almanac Information 14 GHA & LHA Declination Examples Simplifications and Accuracy Methods for Calculating a Position 17 Plane Sailing Mercator Sailing Celestial Navigation and Spherical Trigonometry 19 The PZX Triangle Spherical Formulae Napier’s Rules The Concept of Using a Sextant Altitude Using the altitude of a celestial body is similar to using the altitude of a lighthouse or similar object of known height, to obtain a distance. One object or body provides a distance but the observer can be anywhere on a circle of that radius away from the object. At least two distances/ circles are necessary for a position. (Three avoids ambiguity.) In practice, only that part of the circle near an assumed position would be drawn. Using a Sextant for Celestial Navigation After a few corrections, a sextant gives the true distance of a body if measured on an imaginary sphere surrounding the earth. Using a Nautical Almanac to find the position of the body, the body’s position could be plotted on an appropriate chart and then a circle of the correct radius drawn around it. In practice the circles are usually thousands of miles in radius therefore distances are calculated and compared with an estimate. -
DTA Scoring Form
Daytime Astronomy SHADOWS Score Form Date ____/____/____ Student _______________________________________ Rater _________________ Problem I. (Page 3) Accuracy of results Draw a dot on this map to show where you think Tower C is. Tower C is in Eastern US Tower C is in North Eastern US Tower C is somewhere in between Pennsylvania and Maine Modeling/reasoning/observation How did you figure out where Tower C is? Matched shadow lengths of towers A and B/ pointed flashlight to Equator Tried different locations for tower C/ inferred location of tower C Matched length of shadow C/considered Latitude (distance from Equator) Matched angle of shadow C/ considered Longitude (East-West direction) Problem II. (Page 4) Accuracy of results How does the shadow of Tower A look at 10 AM and 3 PM?... Which direction is the shadow moving? 10 AM shadow points to NNW 10 AM shadow is shorter than noon shadow 3 PM shadow points to NE 3 PM shadow is longer than noon shadow Clockwise motion of shadows Modeling/reasoning/observation How did you figure out what the shadow of Tower A looks like at 10 AM and 3 PM? Earth rotation/ "Sun motion" Sunlight coming from East projects a shadow oriented to West Sunlight coming from West projects a shadow oriented to East Sunlight coming from above us projects a shadow oriented to North Sun shadows are longer in the morning than at noon Morning Sun shadows become shorter and shorter until its noon The shortest Sun shadow is at noon Sun shadows are longer in the afternoon than at noon Afternoon Sun shadows become longer and longer until it gets dark (Over, please) - 1 - 6/95 Problem III. -
What Time Is It?
The Astronomical League A Federation of Astronomical Societies Astro Note E3 – What Time Is It? Introduction – There are many methods used to keep time, each having its own special use and advantage. Until recently, when atomic clocks became available, time was reckoned by the Earth's motions: one rotation on its axis was a "day" and one revolution about the Sun was a "year." An hour was one twenty-fourth of a day, and so on. It was convenient to use the position of the Sun in the sky to measure the various intervals. Apparent Time This is the time kept by a sundial. It is a direct measure of the Sun's position in the sky relative to the position of the observer. Since it is dependent on the observer's location, it is also a local time. Being measured according to the true solar position, it is subject to all the irregularities of the Earth's motion. The reference time is 12:00 noon when the true Sun is on the observer's meridian. Mean Time Many of the irregularities in the Earth's motion are due to its elliptical orbit. In order to add some consistency to the measure of time, we use the concept of mean time. Mean time uses the position of a fictitious "mean Sun" which moves smoothly and uniformly across the sky and is insensitive to the irregularities of the Earth’s motion. A mean solar day is 24 hours long. The "Equation of Time," tabulated in almanacs and represented on maps by the analemma, provides the correction between mean and apparent time to allow for the eccentricity of the Earth's orbit. -
Date Day Peculiarity Position of the Sun Northern Hemisphere Southern
Date Day Peculiarity Position of the Northern Southern sun hemisphere hemisphere March 21 Equinox Length of day Above the From March and night will Equator 21 to be equal ( 0° ) June 21 Spring Autumn June 21 Summer Northern Above the From June 21 Solstice Hemisphere Tropic of to September experiences its Cancer 23 longest day (231⁄2°N) and shortest night Summer Winter September 23 Equinox Length of day Above the From and night will Equator September 23 be equal ( 0° ) to December 22 Autumn Spring December 22 Winter Solstice Northern Above Tropic From Hemisphere of Capricorn December 22 experiences (231⁄2°S) to March 21 its shortest day and longest night. Winter Summer Utharayanam Dakshinayanam The Sun sets its northward apparent The Sun sets its movement southward apparent movement from Tropic of Capricorn (231⁄2°S) and from Tropic of Cancer (231⁄2°N) and it it culminates on Tropic of Cancer (231⁄2°N) culminates on Tropic of Capricorn (231⁄2°S) Following the winter solstice to June 21. Following the summer solstice to December 22 Causes Earth's revolution It is in an elliptical orbit that the Earth revolves around the Sun Tilt of the axis The axis of the Earth is tilted at an angle of ( the inclination of axis ) 661⁄2° from the orbital plane. If measured from the vertical plane this would be 231⁄2° Parallelism of the Earth's axis. The Earth maintains this tilt throughout its revolution. The apparent movement of the Sun. Since the parallelism is maintained same throughout the revolution, the position of the Sun in relation to the Earth varies apparently between Tropic of Cancer (231⁄2° North) and Tropic of Capricorn (231⁄2° South). -
Understanding Celestial Navigation by Ron Davidson, SN Poverty Bay Sail & Power Squadron
Understanding Celestial Navigation by Ron Davidson, SN Poverty Bay Sail & Power Squadron I grew up on the Jersey Shore very near the entrance to New York harbor and was fascinated by the comings and goings of the ships, passing the Ambrose and Scotland light ships that I would watch from my window at night. I wondered how these mariners could navigate these great ships from ports hundreds or thousands of miles distant and find the narrow entrance to New York harbor. Celestial navigation was always shrouded in mystery that so intrigued me that I eventually began a journey of discovery. One of the most difficult tasks for me, after delving into the arcane knowledge presented in most reference books on the subject, was trying to formulate the “big picture” of how celestial navigation worked. Most texts were full of detailed "cookbook" instructions and mathematical formulas teaching the mechanics of sight reduction and how to use the almanac or sight reduction tables, but frustratingly sparse on the overview of the critical scientific principles of WHY and HOW celestial works. My end result was that I could reduce a sight and obtain a Line of Position but I was unsatisfied not knowing “why” it worked. This article represents my efforts at learning and teaching myself 'celestial' and is by no means comprehensive. As a matter of fact, I have purposely ignored significant detail in order to present the big picture of how celestial principles work so as not to clutter the mind with arcane details and too many magical formulas. The USPS JN & N courses will provide all the details necessary to ensure your competency as a celestial navigator.