DOCSLIB.ORG

Equinox Pdf Free Download

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Equinox Pdf Free Download EQUINOX PDF, EPUB, EBOOK Michael White | 432 pages | 05 Aug 2006 | Cornerstone | 9780099505235 | English | London, United Kingdom Equinox PDF Book On any other day of the year, either the southern hemisphere or the Northern Hemisphere tilts a little towards the Sun. Dictionary Entries near equinox equinoctial point equinoctial tide equinoctial year equinox equip equipage equipartition See More Nearby Entries. A famous ancient equinox celebration was the Mayan sacrificial ritual by the main pyramid at Chichen Itza, Mexico. Wikimedia Commons Wikiquote. John A. The mean ecliptic is defined by the barycenter of Earth and the Moon combined, so the Earth wanders slightly above and below the ecliptic due to the orbital tilt of the Moon. Are they just different names for the same thing? In Urban, S. Diagram of the Earth's seasons as seen from the north. What causes these astronomical events? Twilight lasts for more than four hours. Because of the westward precession of the equinoxes, the vernal equinox is now located at the beginning of Pisces. Usually, a satellite will travel either north or south of the Earth's shadow due to its shifted axis throughout the year. Nature , , This point is the origin of some celestial coordinate systems , which are usually rooted to an astronomical epoch since it gradually varies precesses over time:. External Websites. Galactic year Nuclear timescale Precession Sidereal time. Sunrise and sunset can be defined in several ways, but a widespread definition is the time that the top limb of the Sun is level with the horizon. Definition of equinox. These are the moments of first and last direct sunlight. Kids Definition of equinox. History at your fingertips. That reference time is called the equinox of date. Equinox Writer Because the Julian year is longer than the tropical year by about More Definitions for equinox. The depictions presented below can be used for both the northern and the southern hemispheres. The American practical navigator: An epitome of navigation. For the celestial coordinates, see Equinox celestial coordinates. Retrieved 20 March Home Science Astronomy. The March equinox is often used by astronomers to measure a tropical year , the mean time it takes for the Earth to complete a single orbit around the Sun. Chronological dating Geologic time scale International Commission on Stratigraphy. At equinox, the sun is directly over the Earth 's equator. Accessed 21 Oct. The equinoxes happen in March about March 21 and September about September Solar System How many planets are in the solar system? Ecological Modelling. On the equinox, night and day are nearly the same length, 12 hours, all over the world. A third correction for the visual observation of a sunrise or sunset is the angle between the apparent horizon as seen by an observer and the geometric or sensible horizon. Day is usually defined as the period when sunlight reaches the ground in the absence of local obstacles. There are two equinoxes every year, in March and September , when the Sun shines directly on the equator, and the length of night and day are nearly equal. Chronometry Orders of magnitude Metrology. Far right: December solstice. Since the Moon and to a lesser extent the planets causes Earth's orbit to slightly vary from a perfect ellipse , the equinox is officially defined by the Sun's more regular ecliptic longitude rather than by its declination. Strictly speaking, at the equinox, the Sun's ecliptic longitude is zero. In the northern hemisphere, the vernal equinox March conventionally marks the beginning of spring in most cultures and is considered the start of the New Year in the Assyrian calendar , Hindu, and the Persian or Iranian calendars , [a] while the autumnal equinox September marks the beginning of autumn. Knowledge of the equinoxes and solstices is also crucial in developing dependable calendars , another thing the Mayans clearly had got the hang of. There also would be no need to mark equinoxes or solstices. What Does 'Eighty-Six' Mean? The Mayan calendar was very precise in this respect, but today the Mayan calendar is most famous for ending exactly at UTC on the December Solstice. Twilight still lasts about one hour. Some cultures continue to celebrate the equinox today, like the Lakota Tribe of the U. Twilight lasts for more than four hours. Equinox Reviews The seasons on Earth change because the planet is slightly tilted on its axis as it travels around the Sun. For all geostationary satellites, there are a few days around the equinox when the Sun goes directly behind the satellite relative to Earth i. Equinox and the Seasons Equinox descends from aequus , the Latin word for "equal," and nox , the Latin word for "night"—a fitting history for a word that describes days of the year when the daytime and nighttime are equal in length. The March equinox is the spring vernal equinox in the Northern Hemisphere, marking the start of astronomical spring. Look up equinox in Wiktionary, the free dictionary. This point is the origin of some celestial coordinate systems , which are usually rooted to an astronomical epoch since it gradually varies precesses over time:. See for instance Walsh So why does the word refer to 'night'? The mean ecliptic is defined by the barycenter of Earth and the Moon combined, so the Earth wanders slightly above and below the ecliptic due to the orbital tilt of the Moon. On the equinox, night and day are nearly exactly the same length — 12 hours — all over the world. The two solstices happen in June 20 or 21 and December 21 or In the Northern Hemisphere , the March equinox is called the vernal or spring equinox while the September equinox is called the autumnal or fall equinox. English Language Learners Definition of equinox. That reference time is called the equinox of date. The vernal equinox marks the zero point in both the equatorial and ecliptic coordinate systems; horizontal angular distances right ascension in the equatorial system and celestial longitude in the ecliptic system are measured eastward from this point. On March 19, , nature will once again bring us the vernal equinox, the time of year that ushers in spring in the Northern Hemisphere and autumn in the Southern Hemisphere. What Does 'Equinox' Mean? On any other day of the year, either the Southern Hemisphere or the Northern Hemisphere tilts a little towards the Sun. If Earth were not tilted, the Sun would always appear to be directly above the Equator, the amount of light a given location receives would be fixed, and there would be no seasons. Comments on equinox What made you want to look up equinox? Definition of equinox. The autumnal equinox falls about September 23, as the Sun crosses the celestial equator going south. For the same reason, this is also the time when the Sun rises for an observer at one of Earth's rotational poles and sets at the other; for a brief period, both North and South Poles are in daylight. In the Southern Hemisphere, it is the autumnal fall equinox , which marks the beginning of fall. See how many words from the week of Oct 12—18, you get right! Play the game. The American practical navigator: An epitome of navigation. Department of Commerce. UT date and time of equinoxes and solstices on Earth [1] [2]. There is an autumn and a spring equinox festival when days and nights are equal. Equinox Read Online In other words, it is the moment at which the center of the visible Sun is directly above the equator. External Websites. Are they just different names for the same thing? In the Northern Hemisphere, the September equinox marks the start of fall autumn. Day is usually defined as the period when sunlight reaches the ground in the absence of local obstacles. Since the Moon and to a lesser extent the planets causes Earth's orbit to slightly vary from a perfect ellipse , the equinox is officially defined by the Sun's more regular ecliptic longitude rather than by its declination. Test Your Vocabulary. This article is about an astronomical event. Life Of Johnson, Volume 4 of 6 Boswell. Give Feedback External Websites. In the Southern Hemisphere the seasons are reversed. Keep scrolling for more. Galactic year Nuclear timescale Precession Sidereal time. Nature , , Hidden categories: All articles with dead external links Articles with dead external links from June CS1 maint: multiple names: authors list Articles with short description Short description matches Wikidata Use dmy dates from July Articles containing Latin-language text All articles with unsourced statements Articles with unsourced statements from July Articles with unsourced statements from September Articles needing additional references from December All articles needing additional references Articles needing additional references from March Commons category link from Wikidata. Take the quiz Citation Do you know the person or title these quotes desc For a given frequency band, a larger antenna has a narrower beam-width and hence experiences shorter duration "Sun outage" windows. In the Northern Hemisphere, the term vernal point is used for the time of this occurrence and for the precise direction in space where the Sun exists at that time. In the mid-latitudes, daylight increases or decreases by about three minutes per day at the equinoxes, and thus adjacent days and nights only reach within one minute of each other. Login or Register. https://files8.webydo.com/9582763/UploadedFiles/32E30597-4BDA-0F9A-9142-2441E0E7ECF0.pdf https://files8.webydo.com/9583489/UploadedFiles/A1BE2F3B-C689-9F9B-FB60-37DF912080AF.pdf https://files8.webydo.com/9584495/UploadedFiles/0D6D5958-481B-B9C6-5C41-CA1F074EF544.pdf https://files8.webydo.com/9582806/UploadedFiles/364F6706-DF59-C80C-9A1C-2FD2FA8CAD58.pdf https://files8.webydo.com/9582730/UploadedFiles/E9BD7119-F451-F7C4-FFF8-133A7E8BB07E.pdf https://files8.webydo.com/9583515/UploadedFiles/F3E5707E-E9F4-9EFB-8694-3F0A9A91DC8D.pdf.
Load more

Recommended publications
  • PHYS 633: Introduction to Stellar Astrophysics Spring Semester 2006 Rich Townsend ([email protected])
    PHYS 633: Introduction to Stellar Astrophysics Spring Semester 2006 Rich Townsend ([email protected]) Governing Equations In the foregoing analysis, we have seen how a star usually maintains a state of hydrostatic equilibrium. We have seen how the energy created in the star through nuclear reactions, or released through contraction, makes its way out in the form of the star’s luminosity. We have seen how the physical processes responsible for transporting this energy can either be radiation or convection. And, finally, we have seen how nuclear reactions within the star, and transport processes such as convective mixing, can alter the stars chemical composition. These four key pieces of physics lead to 3 + I of the differential equations governing stellar structure (here, I is the number of elements whose evolution we are following). Let’s quickly review these equations. First, we have the most general (spherically-symmetric) form for the equation governing momen- tum conservation, ∂P Gm 1 ∂2r = − − . (1) ∂m 4πr2 4πr2 ∂t2 If the second term on the right-hand side vanishes, then we recover the equation of hydrostatic equilibrium, expressed in Lagrangian form (i.e., derivatives with respect to the mass coordinate m, rather than the radial coordinate r). If this term does not vanish at some point in the star, then the mass shells at that point will being to expand or contract, with an acceleration given by ∂2r/∂t2. Second, we have the most general form for the energy conservation equation, ∂l ∂T δ ∂P = − − c + . (2) ∂m ν P ∂t ρ ∂t The first and second terms on the right-hand side come from nuclear energy gen- eration and neutrino losses, respectively.
    [Show full text]
  • Used Time Scales GEORGE E
    PROCEEDINGS OF THE IEEE, VOL. 55, NO. 6, JIJNE 1967 815 Reprinted from the PROCEEDINGS OF THE IEEI< VOL. 55, NO. 6, JUNE, 1967 pp. 815-821 COPYRIGHT @ 1967-THE INSTITCJTE OF kECTRITAT. AND ELECTRONICSEN~INEERS. INr I’KINTED IN THE lT.S.A. Some Characteristics of Commonly Used Time Scales GEORGE E. HUDSON A bstract-Various examples of ideally defined time scales are given. Bureau of Standards to realize one international unit of Realizations of these scales occur with the construction and maintenance of time [2]. As noted in the next section, it realizes the atomic various clocks, and in the broadcast dissemination of the scale information. Atomic and universal time scales disseminated via standard frequency and time scale, AT (or A), with a definite initial epoch. This clock time-signal broadcasts are compared. There is a discussion of some studies is based on the NBS frequency standard, a cesium beam of the associated problems suggested by the International Radio Consultative device [3]. This is the atomic standard to which the non- Committee (CCIR). offset carrier frequency signals and time intervals emitted from NBS radio station WWVB are referenced ; neverthe- I. INTRODUCTION less, the time scale SA (stepped atomic), used in these emis- PECIFIC PROBLEMS noted in this paper range from sions, is only piecewise uniform with respect to AT, and mathematical investigations of the properties of in- piecewise continuous in order that it may approximate to dividual time scales and the formation of a composite s the slightly variable scale known as UT2. SA is described scale from many independent ones, through statistical in Section 11-A-2).
    [Show full text]
  • What Causes the Seasons? – How Does the Orientation of Earth's Axis Change with Time?
    2.2 The Reason for Seasons • Our goals for learning: – What causes the seasons? – How does the orientation of Earth's axis change with time? © 2014 Pearson Education, Inc. Thought Question TRUE OR FALSE? Earth is closer to the Sun in summer and farther from the Sun in winter. © 2014 Pearson Education, Inc. Thought Question TRUE OR FALSE? Earth is closer to the Sun in summer and farther from the Sun in winter. Hint: When it is summer in America, it is winter in Australia. © 2014 Pearson Education, Inc. Thought Question TRUE OR FALSE! Earth is closer to the Sun in summer and farther from the Sun in winter. • Seasons are opposite in the N and S hemispheres, so distance cannot be the reason. • The real reason for seasons involves Earth's axis tilt. © 2014 Pearson Education, Inc. What causes the seasons? © 2014 Pearson Education, Inc. Axis tilt changes directness of sunlight during the year. © 2014 Pearson Education, Inc. Sun's altitude also changes with seasons Sun’s position at noon in summer: Higher altitude means more direct sunlight. Sun’s position at noon in winter: Lower altitude means less direct sunlight. Summary: The Real Reason for Seasons • Earth's axis points in the same direction (to Polaris) all year round, so its orientation relative to the Sun changes as Earth orbits the Sun. • Summer occurs in your hemisphere when sunlight hits it more directly; winter occurs when the sunlight is less direct. • AXIS TILT is the key to the seasons; without it, we would not have seasons on Earth.
    [Show full text]
  • E a S T 7 4 T H S T R E E T August 2021 Schedule
    E A S T 7 4 T H S T R E E T KEY St udi o key on bac k SEPT EM BER 2021 SC H ED U LE EF F EC T IVE 09.01.21–09.30.21 Bolld New Class, Instructor, or Time ♦ Advance sign-up required M O NDA Y T UE S DA Y W E DNE S DA Y T HURS DA Y F RII DA Y S A T URDA Y S UNDA Y Atthllettiic Master of One Athletic 6:30–7:15 METCON3 6:15–7:00 Stacked! 8:00–8:45 Cycle Beats 8:30–9:30 Vinyasa Yoga 6:15–7:00 6:30–7:15 6:15–7:00 Condiittiioniing Gerard Conditioning MS ♦ Kevin Scott MS ♦ Steve Mitchell CS ♦ Mike Harris YS ♦ Esco Wilson MS ♦ MS ♦ MS ♦ Stteve Miittchellll Thelemaque Boyd Melson 7:00–7:45 Cycle Power 7:00–7:45 Pilates Fusion 8:30–9:15 Piillattes Remiix 9:00–9:45 Cardio Sculpt 6:30–7:15 Cycle Beats 7:00–7:45 Cycle Power 6:30–7:15 Cycle Power CS ♦ Candace Peterson YS ♦ Mia Wenger YS ♦ Sammiie Denham MS ♦ Cindya Davis CS ♦ Serena DiLiberto CS ♦ Shweky CS ♦ Jason Strong 7:15–8:15 Vinyasa Yoga 7:45–8:30 Firestarter + Best Firestarter + Best 9:30–10:15 Cycle Power 7:15–8:05 Athletic Yoga Off The Barre Josh Mathew- Abs Ever 9:00–9:45 CS ♦ Jason Strong 7:00–8:00 Vinyasa Yoga 7:00–7:45 YS ♦ MS ♦ MS ♦ Abs Ever YS ♦ Elitza Ivanova YS ♦ Margaret Schwarz YS ♦ Sarah Marchetti Meier Shane Blouin Luke Bernier 10:15–11:00 Off The Barre Gleim 8:00–8:45 Cycle Beats 7:30–8:15 Precision Run® 7:30–8:15 Precision Run® 8:45–9:45 Vinyasa Yoga Cycle Power YS ♦ Cindya Davis Gerard 7:15–8:00 Precision Run® TR ♦ Kevin Scott YS ♦ Colleen Murphy 9:15–10:00 CS ♦ Nikki Bucks TR ♦ CS ♦ Candace 10:30–11:15 Atletica Thelemaque TR ♦ Chaz Jackson Peterson 8:45–9:30 Pilates Fusion 8:00–8:45
    [Show full text]
  • 14 Timescales in Stellar Interiors
    14Timescales inStellarInteriors Having dealt with the stellar photosphere and the radiation transport so rel- evant to our observations of this region, we’re now ready to journey deeper into the inner layers of our stellar onion. Fundamentally, the aim we will de- velop in the coming chapters is to develop a connection betweenM,R,L, and T in stars (see Table 14 for some relevant scales). More specifically, our goal will be to develop equilibrium models that describe stellar structure:P (r),ρ (r), andT (r). We will have to model grav- ity, pressure balance, energy transport, and energy generation to get every- thing right. We will follow a fairly simple path, assuming spherical symmetric throughout and ignoring effects due to rotation, magneticfields, etc. Before laying out the equations, let’sfirst think about some key timescales. By quantifying these timescales and assuming stars are in at least short-term equilibrium, we will be better-equipped to understand the relevant processes and to identify just what stellar equilibrium means. 14.1 Photon collisions with matter This sets the timescale for radiation and matter to reach equilibrium. It de- pends on the mean free path of photons through the gas, 1 (227) �= nσ So by dimensional analysis, � (228)τ γ ≈ c If we use numbers roughly appropriate for the average Sun (assuming full Table3: Relevant stellar quantities. Quantity Value in Sun Range in other stars M2 1033 g 0.08 �( M/M )� 100 × � R7 1010 cm 0.08 �( R/R )� 1000 × 33 1 3 � 6 L4 10 erg s− 10− �( L/L )� 10 × � Teff 5777K 3000K �( Teff/mathrmK)� 50,000K 3 3 ρc 150 g cm− 10 �( ρc/g cm− )� 1000 T 1.5 107 K 106 ( T /K) 108 c × � c � 83 14.Timescales inStellarInteriors P dA dr ρ r P+dP g Mr Figure 28: The state of hydrostatic equilibrium in an object like a star occurs when the inward force of gravity is balanced by an outward pressure gradient.
    [Show full text]
  • The Mathematics of the Chinese, Indian, Islamic and Gregorian Calendars
    Heavenly Mathematics: The Mathematics of the Chinese, Indian, Islamic and Gregorian Calendars Helmer Aslaksen Department of Mathematics National University of Singapore [email protected] www.math.nus.edu.sg/aslaksen/ www.chinesecalendar.net 1 Public Holidays There are 11 public holidays in Singapore. Three of them are secular. 1. New Year’s Day 2. Labour Day 3. National Day The remaining eight cultural, racial or reli- gious holidays consist of two Chinese, two Muslim, two Indian and two Christian. 2 Cultural, Racial or Religious Holidays 1. Chinese New Year and day after 2. Good Friday 3. Vesak Day 4. Deepavali 5. Christmas Day 6. Hari Raya Puasa 7. Hari Raya Haji Listed in order, except for the Muslim hol- idays, which can occur anytime during the year. Christmas Day falls on a fixed date, but all the others move. 3 A Quick Course in Astronomy The Earth revolves counterclockwise around the Sun in an elliptical orbit. The Earth ro- tates counterclockwise around an axis that is tilted 23.5 degrees. March equinox June December solstice solstice September equinox E E N S N S W W June equi Dec June equi Dec sol sol sol sol Beijing Singapore In the northern hemisphere, the day will be longest at the June solstice and shortest at the December solstice. At the two equinoxes day and night will be equally long. The equi- noxes and solstices are called the seasonal markers. 4 The Year The tropical year (or solar year) is the time from one March equinox to the next. The mean value is 365.2422 days.
    [Show full text]
  • The Basques of Lapurdi, Zuberoa, and Lower Navarre Their History and Their Traditions
    Center for Basque Studies Basque Classics Series, No. 6 The Basques of Lapurdi, Zuberoa, and Lower Navarre Their History and Their Traditions by Philippe Veyrin Translated by Andrew Brown Center for Basque Studies University of Nevada, Reno Reno, Nevada This book was published with generous financial support obtained by the Association of Friends of the Center for Basque Studies from the Provincial Government of Bizkaia. Basque Classics Series, No. 6 Series Editors: William A. Douglass, Gregorio Monreal, and Pello Salaburu Center for Basque Studies University of Nevada, Reno Reno, Nevada 89557 http://basque.unr.edu Copyright © 2011 by the Center for Basque Studies All rights reserved. Printed in the United States of America Cover and series design © 2011 by Jose Luis Agote Cover illustration: Xiberoko maskaradak (Maskaradak of Zuberoa), drawing by Paul-Adolph Kaufman, 1906 Library of Congress Cataloging-in-Publication Data Veyrin, Philippe, 1900-1962. [Basques de Labourd, de Soule et de Basse Navarre. English] The Basques of Lapurdi, Zuberoa, and Lower Navarre : their history and their traditions / by Philippe Veyrin ; with an introduction by Sandra Ott ; translated by Andrew Brown. p. cm. Translation of: Les Basques, de Labourd, de Soule et de Basse Navarre Includes bibliographical references and index. Summary: “Classic book on the Basques of Iparralde (French Basque Country) originally published in 1942, treating Basque history and culture in the region”--Provided by publisher. ISBN 978-1-877802-99-7 (hardcover) 1. Pays Basque (France)--Description and travel. 2. Pays Basque (France)-- History. I. Title. DC611.B313V513 2011 944’.716--dc22 2011001810 Contents List of Illustrations..................................................... vii Note on Basque Orthography.........................................
    [Show full text]
  • Stellar Structure and Evolution
    Lecture Notes on Stellar Structure and Evolution Jørgen Christensen-Dalsgaard Institut for Fysik og Astronomi, Aarhus Universitet Sixth Edition Fourth Printing March 2008 ii Preface The present notes grew out of an introductory course in stellar evolution which I have given for several years to third-year undergraduate students in physics at the University of Aarhus. The goal of the course and the notes is to show how many aspects of stellar evolution can be understood relatively simply in terms of basic physics. Apart from the intrinsic interest of the topic, the value of such a course is that it provides an illustration (within the syllabus in Aarhus, almost the first illustration) of the application of physics to “the real world” outside the laboratory. I am grateful to the students who have followed the course over the years, and to my colleague J. Madsen who has taken part in giving it, for their comments and advice; indeed, their insistent urging that I replace by a more coherent set of notes the textbook, supplemented by extensive commentary and additional notes, which was originally used in the course, is directly responsible for the existence of these notes. Additional input was provided by the students who suffered through the first edition of the notes in the Autumn of 1990. I hope that this will be a continuing process; further comments, corrections and suggestions for improvements are most welcome. I thank N. Grevesse for providing the data in Figure 14.1, and P. E. Nissen for helpful suggestions for other figures, as well as for reading and commenting on an early version of the manuscript.
    [Show full text]
  • How Long Is a Year.Pdf
    How Long Is A Year? Dr. Bryan Mendez Space Sciences Laboratory UC Berkeley Keeping Time The basic unit of time is a Day. Different starting points: • Sunrise, • Noon, • Sunset, • Midnight tied to the Sun’s motion. Universal Time uses midnight as the starting point of a day. Length: sunrise to sunrise, sunset to sunset? Day Noon to noon – The seasonal motion of the Sun changes its rise and set times, so sunrise to sunrise would be a variable measure. Noon to noon is far more constant. Noon: time of the Sun’s transit of the meridian Stellarium View and measure a day Day Aday is caused by Earth’s motion: spinning on an axis and orbiting around the Sun. Earth’s spin is very regular (daily variations on the order of a few milliseconds, due to internal rearrangement of Earth’s mass and external gravitational forces primarily from the Moon and Sun). Synodic Day Noon to noon = synodic or solar day (point 1 to 3). This is not the time for one complete spin of Earth (1 to 2). Because Earth also orbits at the same time as it is spinning, it takes a little extra time for the Sun to come back to noon after one complete spin. Because the orbit is elliptical, when Earth is closest to the Sun it is moving faster, and it takes longer to bring the Sun back around to noon. When Earth is farther it moves slower and it takes less time to rotate the Sun back to noon. Mean Solar Day is an average of the amount time it takes to go from noon to noon throughout an orbit = 24 Hours Real solar day varies by up to 30 seconds depending on the time of year.
    [Show full text]
  • Equation of Time — Problem in Astronomy M
    This paper was awarded in the II International Competition (1993/94) "First Step to Nobel Prize in Physics" and published in the competition proceedings (Acta Phys. Pol. A 88 Supplement, S-49 (1995)). The paper is reproduced here due to kind agreement of the Editorial Board of "Acta Physica Polonica A". EQUATION OF TIME | PROBLEM IN ASTRONOMY M. Muller¨ Gymnasium M¨unchenstein, Grellingerstrasse 5, 4142 M¨unchenstein, Switzerland Abstract The apparent solar motion is not uniform and the length of a solar day is not constant throughout a year. The difference between apparent solar time and mean (regular) solar time is called the equation of time. Two well-known features of our solar system lie at the basis of the periodic irregularities in the solar motion. The angular velocity of the earth relative to the sun varies periodically in the course of a year. The plane of the orbit of the earth is inclined with respect to the equatorial plane. Therefore, the angular velocity of the relative motion has to be projected from the ecliptic onto the equatorial plane before incorporating it into the measurement of time. The math- ematical expression of the projection factor for ecliptic angular velocities yields an oscillating function with two periods per year. The difference between the extreme values of the equation of time is about half an hour. The response of the equation of time to a variation of its key parameters is analyzed. In order to visualize factors contributing to the equation of time a model has been constructed which accounts for the elliptical orbit of the earth, the periodically changing angular velocity, and the inclined axis of the earth.
    [Show full text]
  • Research on the Precession of the Equinoxes and on the Nutation of the Earth’S Axis∗
    Research on the Precession of the Equinoxes and on the Nutation of the Earth’s Axis∗ Leonhard Euler† Lemma 1 1. Supposing the earth AEBF (fig. 1) to be spherical and composed of a homogenous substance, if the mass of the earth is denoted by M and its radius CA = CE = a, the moment of inertia of the earth about an arbitrary 2 axis, which passes through its center, will be = 5 Maa. ∗Leonhard Euler, Recherches sur la pr´ecession des equinoxes et sur la nutation de l’axe de la terr,inOpera Omnia, vol. II.30, p. 92-123, originally in M´emoires de l’acad´emie des sciences de Berlin 5 (1749), 1751, p. 289-325. This article is numbered E171 in Enestr¨om’s index of Euler’s work. †Translated by Steven Jones, edited by Robert E. Bradley c 2004 1 Corollary 2. Although the earth may not be spherical, since its figure differs from that of a sphere ever so slightly, we readily understand that its moment of inertia 2 can be nonetheless expressed as 5 Maa. For this expression will not change significantly, whether we let a be its semi-axis or the radius of its equator. Remark 3. Here we should recall that the moment of inertia of an arbitrary body with respect to a given axis about which it revolves is that which results from multiplying each particle of the body by the square of its distance to the axis, and summing all these elementary products. Consequently this sum will give that which we are calling the moment of inertia of the body around this axis.
    [Show full text]
  • Zerohack Zer0pwn Youranonnews Yevgeniy Anikin Yes Men
    Zerohack Zer0Pwn YourAnonNews Yevgeniy Anikin Yes Men YamaTough Xtreme x-Leader xenu xen0nymous www.oem.com.mx www.nytimes.com/pages/world/asia/index.html www.informador.com.mx www.futuregov.asia www.cronica.com.mx www.asiapacificsecuritymagazine.com Worm Wolfy Withdrawal* WillyFoReal Wikileaks IRC 88.80.16.13/9999 IRC Channel WikiLeaks WiiSpellWhy whitekidney Wells Fargo weed WallRoad w0rmware Vulnerability Vladislav Khorokhorin Visa Inc. Virus Virgin Islands "Viewpointe Archive Services, LLC" Versability Verizon Venezuela Vegas Vatican City USB US Trust US Bankcorp Uruguay Uran0n unusedcrayon United Kingdom UnicormCr3w unfittoprint unelected.org UndisclosedAnon Ukraine UGNazi ua_musti_1905 U.S. Bankcorp TYLER Turkey trosec113 Trojan Horse Trojan Trivette TriCk Tribalzer0 Transnistria transaction Traitor traffic court Tradecraft Trade Secrets "Total System Services, Inc." Topiary Top Secret Tom Stracener TibitXimer Thumb Drive Thomson Reuters TheWikiBoat thepeoplescause the_infecti0n The Unknowns The UnderTaker The Syrian electronic army The Jokerhack Thailand ThaCosmo th3j35t3r testeux1 TEST Telecomix TehWongZ Teddy Bigglesworth TeaMp0isoN TeamHav0k Team Ghost Shell Team Digi7al tdl4 taxes TARP tango down Tampa Tammy Shapiro Taiwan Tabu T0x1c t0wN T.A.R.P. Syrian Electronic Army syndiv Symantec Corporation Switzerland Swingers Club SWIFT Sweden Swan SwaggSec Swagg Security "SunGard Data Systems, Inc." Stuxnet Stringer Streamroller Stole* Sterlok SteelAnne st0rm SQLi Spyware Spying Spydevilz Spy Camera Sposed Spook Spoofing Splendide
    [Show full text]