OK, so how do modern analogs of the Babylonian ephemerides actually work?
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Nowadays, ephemerides are usually generated using software, but they're said to have been distributed as early as the 4th century BCE.
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Although ephemerides have been used since ancient times, the tables generated today rely on computers and mathematical models to determine the planets' placements.
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By the Middle Ages, astronomers had compiled long tables of lunar, solar, and planetary crossings — called "ephemerides" — which were used to predict eclipses.
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Read on to learn how each sign affects the new moon's pensive energy, and to find out when new moon will arrive in your sign next (dates are in EST, according to NASA and astrologer Annie Heese's ephemerides).
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In later ephemerides, Teph is essentially equivalent to the IAU definition of TCB.
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Ephemerides are used in celestial navigation and astronomy. They are also used by astrologers.
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Ephemerides aeris perpetuae, 1560 Antonio Mizauld (1510–1578) was a French astronomer and physician.
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For example E M Standish (1997) Jet Propulsion Laboratory Planetary and Lunar Ephemerides, (including DE200, DE405 and DE406) published on CD-ROM and other (e.g. online) formats.(History of USNO Almanac Publications) Later examples of the Development Ephemerides supported the navigation of specific NASA planetary space missions with precise results.
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Ephemeris time based on the standard adopted in 1952 was introduced into the Astronomical Ephemeris (UK) and the American Ephemeris and Nautical Almanac, replacing UT in the main ephemerides in the issues for 1960 and after.ESAA 1992, at p.612. (But the ephemerides in the Nautical Almanac, by then a separate publication for the use of navigators, continued to be expressed in terms of UT.) The ephemerides continued on this basis through 1983 (with some changes due to adoption of improved values of astronomical constants), after which, for 1984 onwards, they adopted the JPL ephemerides. Previous to the 1960 change, the 'Improved Lunar Ephemeris' had already been made available in terms of ephemeris time for the years 1952-1959"Improved Lunar Ephemeris", US Government Printing Office, 1954.
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Positions and velocities of the Sun, Earth, Moon, and planets, along with the orientation of the Moon, are stored as Chebyshev polynomial coefficients fit in 32-day-long segments. The ephemerides are now available via World Wide Web and FTPSee the JPL FTP site with ephemerides (data files), source code (for access and basic processing of the data to recover positions and velocities), and documentation. as data files containing the Chebyshev coefficients, along with source code to recover (calculate) positions and velocities.See JPL Planetary and Lunar Ephemerides Export Information README.
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From 1734 until 1747, the Academy published a journal known as Ephemerides Barometrico- Medicas Matritenses, which contained criticism of medical and scientific literature. The journal also involved the cataloguing of weather and atmospheric conditions in an attempt to explain the effects of such weather on individuals' health. Ephemerides Barometrico-Medicas Matritenses has been described as pseudoscientific by modern scholars.
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He published the astronomical tables Ephemerides astronomicae ad meridianum Vindobonemsem ("Ephemerides for the Meridian of Vienna"). He and his assistant János Sajnovics went to Vardø in the far north of Norway (then part of Denmark-Norway) to observe the 1769 transit of Venus. He was elected as a foreign member of the Royal Danish Academy of Sciences and Letters on October 13, 1769.
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It is the largest of the ephemerides files at 3.4 gigabytes. This ephemeris file is used by the JPL Horizons On- Line Ephemeris System.
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This process is repeated as necessary. For planetary motions, a few (3–5) iterations are sufficient to match the accuracy of the underlying ephemerides.
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Hopfner's early work was mostly concerned with astronomy and meteorology. In collaboration with Johann Palisa, he determined the trajectories and ephemerides of a number of planetoids.
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See John Sullivan, 'Night and Light: the Poet John of the Cross and the Exultet of the Easter Liturgy', Ephemerides Carmeliticae, 30:1 (1979), pp. 52-68.
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Most of their time was spent calculating newer, better, and more accurate ephemerides for astrological purposes using the rapidly advancing astronomical methods and tools of the day.
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Obliquity of the ecliptic for 20,000 years, from Laskar (1986). The red point represents the year 2000. The exact angular value of the obliquity is found by observation of the motions of Earth and planets over many years. Astronomers produce new fundamental ephemerides as the accuracy of observation improves and as the understanding of the dynamics increases, and from these ephemerides various astronomical values, including the obliquity, are derived.
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An ephemeris is usually only correct for a particular location on the Earth. In many cases, the differences are too small to matter. However, for nearby asteroids or the Moon, they can be quite important. Other modern ephemerides recently created are the EPM (Ephemerides of Planets and the Moon), from the Russian Institute for Applied Astronomy of the Russian Academy of Sciences, and the INPOP (') by the French IMCCE.
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She works with four colleges, including Seine-Saint-Denis, Bobigny and Villetaneuse. In 2018 Ephemerides launched in Bamako. She funds the project with money from Fondation de France.
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Reflecting the continuing influx of new data and observations, NASA's Jet Propulsion Laboratory (JPL) has revised its published ephemerides nearly every year for the past 20 years.Georgij A. Krasinsky and Victor A. Brumberg, Secular Increase of Astronomical Unit from Analysis of the Major Planet Motions, and its Interpretation Celestial Mechanics and Dynamical Astronomy 90: 267–288, (2004). Solar System ephemerides are essential for the navigation of spacecraft and for all kinds of space observations of the planets, their natural satellites, stars, and galaxies. Scientific ephemerides for sky observers mostly contain the positions of celestial bodies in right ascension and declination, because these coordinates are the most frequently used on star maps and telescopes.
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For daily ephemerides, the daily positions of a planet were not as important as the astrologically significant dates when the planet crossed from one zodiacal sign to the next.
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Weaver's The British Telescope ephemerides (astronomical tables) is considered an important 18th-century publication on the movement of planets.Devore, Nicholas (1947): Encyclopedia of Astrology. Reprint: Astrology Classics (2005). p. 177.
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In 1765, Wales was employed by the Astronomer Royal Nevil Maskelyne as a computer, calculating ephemerides that could be used to establish the longitude of a ship, for Maskelyne's Nautical Almanac.
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The neighbouring spring has been called Cissa (from kissa "jay"), ever since. According to Robert Graves, this story is an anecdotal fancy, supposed to account for the name of the spring, which may have been sacred to a jay-totem clan. Stephen Gosson named one of his books The Ephemerides of Phialo, "ephemerides" here meaning an account similar to the Works and Days of Hesiod, and began his text with a discussion of the sacrifices offered to Heracles.
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In astronomy, secular variations are contrasted with periodic phenomena. In particular, astronomical ephemerides use secular to label the longest-lasting or non-oscillatory perturbations in the motion of planets, as opposed to periodic perturbations which exhibit repetition over the course of a time frame of interest. In this context it is referred to as secular motion. Solar System ephemerides are essential for the navigation of spacecraft and for all kinds of space observations of the planets, their natural satellites, stars and galaxies.
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During his stay in Brussels Stadius published his first work, the Ephemerides novae et auctae, first published by the publisher Arnold Birckmann of Cologne in 1554. An ephemeris (plural: ephemerides) (from the Greek word ephemeros, "daily") was, traditionally, a table providing the positions (given in a Cartesian coordinate system, or in right ascension and declination or, for astrologers, in longitude along the zodiacal ecliptic), of the Sun, the Moon, and the planets in the sky at a given moment in time; the astrological positions are usually given for either noon or midnight depending on the particular ephemeris that is used. This work posited a link between mathematics and medicine and was influential on Tycho Brahe and Nostradamus. Stadius had been encouraged to publish the Ephemerides by his old teacher Gemma Frisius.
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DE402 introduced coordinates referred to the International Celestial Reference Frame (ICRF). The JPL ephemerides have been the basis of the Astronomical Almanac since 1981's DE200. The current (2018) Almanac is derived from DE430.
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In De refractionibus astronomicis,Ephemerides astronomicae anni 1788: Appendix ad ephemerides Anni 1788 (Appresso Giuseppe Galeazzi, Milano, 1787), pp. 164–277. Oriani showed that astronomical refraction could be expanded as a series of odd powers of (tan Z), where Z is the observed zenith distance. Such a series had previously been derived by J. H. Lambert, who dropped all but the first term. However, Oriani investigated the higher terms, and he found that neither of the first two terms depended on the structure of the atmosphere.
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The ephemeris is a table of the calculated positions of astronomical objects and various other data, usually for a specific time of the day, either noon or midnight. A uniform time measurement is needed to establish accuracy, and ephemerides will use variously Greenwich Mean Time, Universal Time or Ephemeris Time. Historically, the ephemeris was used for astrology and dates back to ancient Babylon. However, ephemerides became highly useful to navigators and astronomers, and were officially recognised by governments from about the early modern period.
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Hence, it is possible to construct ephemerides entirely in SI units, which is increasingly becoming the norm. A 2004 analysis of radiometric measurements in the inner Solar System suggested that the secular increase in the unit distance was much larger than can be accounted for by solar radiation, + metres per century. The measurements of the secular variations of the astronomical unit are not confirmed by other authors and are quite controversial. Furthermore, since 2010, the astronomical unit has not been estimated by the planetary ephemerides.
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In order to calculate longitude a sailor would need to know the time difference between his current location and a fixed point somewhere on earth, usually the port of call. Even if one could determine the time of day while in deep waters, they still needed to know the time at their home port. The answer was the ephemerides, astronomical charts plotting the location of the stars over a distinct period of time. The German astronomer Regiomontanus published an accurate day-to-day Ephemerides in 1474.
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Yale University Press (2013). Retrieved 7 August 2013 Weaver supported the heliocentric view of the universe. He opposed criticism of the accuracy of ephemerides formulated by Edmond Halley, the Astronomer Royal, particularly that from Tycho Wing.
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Besides separate sermons and school books, Russell published The History of Sion College, London, 1859, and edited for the first time The Ephemerides of Isaac Casaubon, with a Latin preface and notes, 2 vols. Oxford, 1850.
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Standish has also dealt with the Pioneer Anomaly issue by modeling it in a modified version of the usual ephemerides and fitting such a new dynamical theory of planetary motions to the usual, well-established observational data set.
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Moonia is a genus of Asian and Australian flowering plants in the daisy family.Arnott, George Arnott Walker. 1836. Nova Acta Physico-Medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta 18: 348Tropicos, Moonia Arn.
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James Lindsay Hilton (born February 21, 1957) has been an astronomer at the United States Naval Observatory since 1986. In 1999 he published a new set of ephemerides for 15 of the largest asteroids for use in the Astronomical Almanac.
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With the definitions used before 2012, the astronomical unit was dependent on the heliocentric gravitational constant, that is the product of the gravitational constant, G, and the solar mass, . Neither G nor can be measured to high accuracy separately, but the value of their product is known very precisely from observing the relative positions of planets (Kepler's Third Law expressed in terms of Newtonian gravitation). Only the product is required to calculate planetary positions for an ephemeris, so ephemerides are calculated in astronomical units and not in SI units. The calculation of ephemerides also requires a consideration of the effects of general relativity.
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Astronomers produce new fundamental ephemerides as the accuracy of observation improves and as the understanding of the dynamics increases, and from these ephemerides various astronomical values, including the obliquity, are derived. Obliquity of the ecliptic for 20,000 years, from Laskar (1986). Note that the obliquity varies only from 24.2° to 22.5° during this time. The red point represents the year 2000. Until 1983 the obliquity for any date was calculated from work of Newcomb, who analyzed positions of the planets until about 1895: where is the obliquity and is tropical centuries from B1900.0 to the date in question.
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Modern ephemerides are often computed electronically, from mathematical models of the motion of astronomical objects and the Earth. However, printed ephemerides are still produced, as they are useful when computational devices are not available. The astronomical position calculated from an ephemeris is given in the spherical polar coordinate system of right ascension and declination. Some of the astronomical phenomena of interest to astronomers are eclipses, apparent retrograde motion/planetary stations, planetary es, sidereal time, positions for the mean and true nodes of the moon, the phases of the Moon, and the positions of minor celestial bodies such as Chiron.
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For scientific uses, a modern planetary ephemeris comprises software that generates positions of planets and often of their satellites, asteroids, or comets, at virtually any time desired by the user. Typically, such ephemerides cover several centuries, past and future; the future ones can be covered because the field of celestial mechanics has developed several accurate theories. Nevertheless, there are secular phenomena which cannot adequately be considered by ephemerides. The greatest uncertainties in the positions of planets are caused by the perturbations of numerous asteroids, most of whose masses and orbits are poorly known, rendering their effect uncertain.
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High-precision ephemerides of sun, moon and planets were developed and calculated at the Jet Propulsion Laboratory (JPL) over a long period, and the latest available were adopted for the ephemerides in the Astronomical Almanac starting in 1984. Although not an IAU standard, the ephemeris time argument Teph has been in use at that institution since the 1960s. The time scale represented by Teph has been characterized as a relativistic coordinate time that differs from Terrestrial Time only by small periodic terms with an amplitude not exceeding 2 milliseconds of time: it is linearly related to, but distinct (by an offset and constant rate which is of the order of 0.5 s/a) from the TCB time scale adopted in 1991 as a standard by the IAU. Thus for clocks on or near the geoid, Teph (within 2 milliseconds), but not so closely TCB, can be used as approximations to Terrestrial Time, and via the standard ephemerides Teph is in widespread use.
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Ephemerides Zagrabienses was the first Croatian newspaper, established in 1771 in Zagreb. Fifty issues of the four-page newspaper in Latin were published by Antun Jandera, a Czech-born printer. Little else is known about the newspaper, as there are no surviving copies.
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The Sternenbote is a monthly scientific journal on astronomy published by the Astronomisches Büro (Vienna). It was established in 1958, and contents include ephemerides of comets and other solar system objects and observation reports. It is abstracted and indexed in the Astrophysics Data System.
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Alongside her research, Kébé campaigns to improve access to astronomy and physics. She appeared on France Inter in 2017. Kébé founded Ephemerides, a program that provides astronomy classes for high school students from disadvantaged backgrounds. It teaches students that are 12 to 15 years old.
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At present she is head of the Laboratory of Ephemeris Astronomy of this institute. Major research interests of Dr. Pitjeva include the construction of numerical ephemerides of the planets, the determination of the planets' and asteroids' masses, the parameters of planet rotation and planetary topography, the solar corona and oblateness and general relativity testing. She is one of creators of the numerical Ephemerides of Planets and the Moon (EPM) of IAA RAS that originated in the seventies of the past century and have been developed since that time. The version of the EPM2004 ephemeris has been adopted as the ephemeris basis of Russian Astronomical Yearbook since 2006.
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The updated EPM2008 ephemerides are available to outside users via ftp. The works of Pitjeva have recently been used by several scientists to test several models of modified gravity in the Solar System. Dr. Pitjeva has also contributed to a better understanding an influence of asteroids and Trans- Neptunian Objects on the planets' motion. Recently Dr. Pitjeva collaborated with Dr. Standish and proposed to the IAU Working Group on Numerical Standards for Fundamental Astronomy (NSFA) the values of the masses of the three largest asteroids, the Moon-Earth mass ratio and the astronomical unit in meters, mainly obtained while fitting the constructed DE (JPL) and EPM (IAA RAS) planet ephemerides.
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The set of physical laws and numerical constants used in the calculation of the ephemeris must be self- consistent and precisely specified. The ephemeris must be calculated strictly in accordance with this set, which represents the most current knowledge of all relevant physical forces and effects. Current fundamental ephemerides are typically released with exact descriptions of all mathematical models, methods of computation, observational data, and adjustment to the observations at the time of their announcement.See, for instance, ; ; This may not have been the case in the past, as fundamental ephemerides were then computed from a collection of methods derived over a span of decades by many researchers.
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Robert Thomas Cross (1850–1923) became the next Raphael, obtaining the copyright to the publication at some time in the 1870s.Lewis, James R., Astrology Encyclopaedia, Detroit: Gale Research, 1994. Robert Cross Smith was also responsible for popularising the system of astrological house division known as the Placidean, after the Italian monk Placidus de Titus (d. 1668). Placidus house tables, for locations in northern latitudes, are still listed in Raphael's Ephemeris, nowadays issued by W. Foulsham, a British publisher founded in 1819. (They first published Raphael's in 1836.) The latest ephemerides have been calculated using data obtained from the astronomical ephemerides produced by NASA’s Jet Propulsion Laboratory in Pasadena, California.
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Observers in different locations, that are in relative motion or at different altitudes, can disagree about the rates of each other's clocks, owing to effects described by the theory of relativity. As a result, TT (even as a theoretical ideal) does not match the proper time of all observers. In relativistic terms, TT is described as the proper time of a clock located on the geoid (essentially mean sea level).For example, IAU Commission 4 (Ephemerides), Recommendations to IAU General Assembly 1976, Notes on Recommendation 5, note 1, as well as other sources, indicate the time scale for apparent geocentric ephemerides as a proper time.
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It is the only public source of astronomical ephemerides in Serbia. Magazine articles can roughly be divided into works, news and others. The articles are mostly written for the highschool level, although there are those for the higher level, meant for the smaller circle of readers.
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Explanatory Supplement (1961), sec. 2B From 1984, the Jet Propulsion Laboratory's DE series of computer-generated ephemerides took over as the fundamental ephemeris of the Astronomical Almanac. Obliquity based on DE200, which analyzed observations from 1911 to 1979, was calculated: where hereafter is Julian centuries from J2000.0.
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A single reference geographically close to the target will give a high degree of cancellation of the location effects of ephemeris error. Measurements on signals from multiple reference sites can be used to improve the accuracy of the satellite ephemerides thereby provided improved geolocation accuracy generally.
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Parker revised the tenth edition of William Eland's Tutor to Astrology (1704), and edited John Gadbury's Ephemerides of the Celestial Motions for XX years (1709–28) in 1709. In 1719 he issued the first number of a West India Almanack, London, but did not continue it.
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Early in January 1928, Duchamp said that he could no longer bear the responsibility and confinement of marriage, and they were soon divorced.Hulten, Pontus. Marcel Duchamp, Work and Life: Ephemerides on and about Marcel Duchamp and Rrose Selavy, 1887–1968. Pages 8–9 June (1927) to 25 January (1928). .
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At the academy she worked as his unofficial, but recognised assistant. Women’s position in the sciences was akin to their position in the guilds, valued but subordinate. Together they made observations and performed calculations to produce calendars and ephemerides. From 1697, the Kirchs also began recording weather information.
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Dr. Wahl had been computing all the satellite ephemerides by hand using a Friden Square Root Calculator, the most advanced mechanical calculator then available. The method for computing ephemerides (documented in detail in a 1960 report by P.M. Fitzpatrick and G.B. Findley) was originally developed by Dr. Wahl, based on historic astronomical methods. In late August 1958, Space Track obtained its first computer, an IBM 610, used in conjunction with the Cambridge Research Center IBM 650. The IBM 610 was a very primitive machine, the programing of which was done with a plug board (similar to the ones used for IBM accounting machines in the early 1950s) and a punched paper tape.
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Ephemerides Theologicae Lovanienses is a quarterly peer-reviewed academic journal covering theology and canon law. It was established in 1924 and is published by Peeters. It publishes articles, notes and comments, and reviews in English, French, and German. The journal is abstracted and indexed in the ATLA Religion Database and Scopus.
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Cephalopappus is a genus of flowering plants in the daisy family.Nees von Esenbeck, Christian Gottfried Daniel & Martius, Carl Friedrich Philipp von. 1824. Nova Acta Physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta 12: 5. in Latin with line drawing as illustrationTropicos, Cephalopappus Nees & Mart.
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Pontus de Tyard met "Jofranc Offusien" a few years later, around 1556, in Dieppe. Offusius claimed to have conducted thousands of astronomical observations and published a book of ephemerides for 1557. De Divina facultate presented an astrological system where the distances to planets are connected with Plato's solids.Stephenson, loc. cit.
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298v-299r; Concistoro 340, c.14v 15 Archivio di Stato di Siena, Concistoro N° 260, c. 19 and 359, c.29v. 16 A. ALLEGRETTI, “Ephemerides senenses 1450-1496” in “Rerum Italicarum Scriptores” a cura di L.A Muratori, vol. XXXIII, 1733, pag. 789. 17 Archivio di Stato di Siena, Balia 596, n° 52.
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Jet Propulsion Laboratory (JPL) ephemerides do not use things such as periods, eccentricities, etc. Instead, JPL integrates the equations of motion in Cartesian coordinates (x,y,z), and adjusts the initial conditions in order to fit modern, highly accurate measurements of planetary positions. As of August 2015, Horizons now uses ephemeris DE431.
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Statue of the Archangel > Michael, University of Bonn, slaying Satan represented as a dragon. Quis ut > Deus is inscribed on his shield. An article in the Roman journal Ephemerides > Liturgicae (V. LXIX, pages 54–60) in 1955 gave an account in Latin and > Italian of how the Saint Michael prayer (in the Leonine Prayers) originated.
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Johannes Stadius. Johannes Stadius or Estadius (Dutch: Jan Van Ostaeyen; French: Jean Stade) (ca. 1 May 1527 – 17 June 1579), was a Flemish astronomer, astrologer, and mathematician. He was one of the important late 16th-century makers of ephemerides, which gave the positions of astronomical objects in the sky at a given time or times.
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It contains an exposition of the astronomy of the ancient Babylonians, worked out from their Ephemerides of the moon and the planets. This was supplemented by Die babylonische Berechnung des Neumondes (Stimmen aus Maria-Laach, Vol. XXXIX, pp. 229–240). He was also the author of a number of articles in the Zeitschrift für Assyriologie.
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He was deputy editor of the Ephemerides Astronomicae of Vienna from 1782 until he became editor in 1792. He continued as editor, collaborating with Joanne Bürg, until he retired in 1806. He made a series of measurements of celestial bodies, which were published from 1787 until 1806. These included the Tabulae Mercurii, Martis, Veneris, Solares.
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Campion, 1982. p. 47. The distinction between astrology and astronomy was not entirely clear. Advances in astronomy were often motivated by the desire to improve the accuracy of astrology. Ephemerides with complex astrological calculations, and almanacs interpreting celestial events for use in medicine and for choosing times to plant crops, were popular in Elizabethan England.
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The Berliner Astronomisches Jahrbuch (abbrev. B.A.J.) is an astronomical ephemeris almanac and the longest publication series in astronomy. It was a compendium of ephemerides of all large Solar System bodies and of fundamental stars which define the celestial reference system. The B.A.J. series was founded by Johann Elert Bode, and is thus sometimes referred to as Bode's Astronomisches Jahrbuch.
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This minor planet was named "Itha", picked from the Lahrer Hinkender Bote, an almanac which was published in Lahr, southern Germany. Especially in the alemannic-speaking region, a Hinkender Bote (lit. "limping messenger") was very popular from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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The equation of time is the east or west component of the analemma, a curve representing the angular offset of the Sun from its mean position on the celestial sphere as viewed from Earth. The equation of time values for each day of the year, compiled by astronomical observatories, were widely listed in almanacs and ephemerides.
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Iselin remained a friend of Pestalozzi and encouraged him to continue writing. In 1780 Pestalozzi published anonymously in Die Ephemerides a series of aphorisms entitled The Evening Hours of a Hermit. They are his earliest works which outline ideas that would later be known as Pestalozzian. The aphorisms attracted little attention at the time of publication.
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JPL's fundamental ephemerides have been continually updated. For instance, the Astronomical Almanac for 2010 specifies:Astronomical Almanac 2010, p. B52 : These expressions for the obliquity are intended for high precision over a relatively short time span, perhaps several centuries. J. Laskar computed an expression to order good to 0.02″ over 1000 years and several arcseconds over 10,000 years.
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Bogoslovni vestnik, subtitled Theological Quarterly, Ephemerides Theologicae, is a quarterly peer-reviewed academic journal on theology published by the Faculty of Theology of the University of Ljubljana. It is the oldest Slovenian scholarly journal in the field of humanities. Articles are in English, French, German, Italian, Latin, or Slovenian. The journal is abstracted in Religious and Theological Abstracts.
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He publishes the Nakano Notes on comet observations and ephemerides. In 2001 he won the Amateur Achievement Award of the Astronomical Society of the Pacific. The asteroid 3431 Nakano is named after him, and asteroid 3983 Sakiko is named after his sister. 1026 Ingrid was reidentified in 1986 by Syuichi Nakano, ending its time as a lost asteroid.
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First, these ephemerides are tied to optical and radar observations of planetary motion, and the TDB time scale is fitted so that Newton's laws of motion, with corrections for general relativity, are followed. Next, the time scales based on Earth's rotation are not uniform and therefore, are not suitable for predicting the motion of bodies in our solar system.
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A fundamental ephemeris is the basis from which apparent ephemerides, phenomena, and orbital elements are computed for astronomical, nautical, and surveyors' almanacs. Apparent ephemerides give positions and motions of Solar System bodies as seen by observers from the surface of Earth, and are useful for astronomers, navigators, and surveyors in planning observations and in reducing the data acquired, although much of the work of latter two has been supplanted by GPS technology. Phenomena are events related to the configurations of Solar System bodies, for instance rise and set times, phases, eclipses and occultations, and have many civil and scientific applications. Orbital elements are descriptions of the motion of a body at a particular instant, used for further short-time-span calculation of the body's position when high accuracy is not required.
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' Wing issued ephemerides for twenty years (1652–1671), which John Flamsteed considered to be the most accurate of their time. As a very young man Flamsteed maintained a correspondence with Wing (who died in 1668).E.G. Forbes, L. Murdin and F. Wilmoth, The Correspondence of John Flamsteed, The First Astronomer Royal (Institute of Physics/CRC Press, London 1995) Vol. 1, passim.
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This minor planet was named "Toni", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Imhilde", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Hildrun", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Algunde", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Gunila", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast/name days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Wallia", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named Otthild, after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Jucunda", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Otila", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Jovita", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic- speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Herluga", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Kunigunde", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Chlosinde", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Kordula", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic- speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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This minor planet was named "Romilda", after a female name picked from the Lahrer Hinkender Bote, published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast and name days, the dates of important fairs and astronomical ephemerides.
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After returning to Ellicott's Mills, Banneker made astronomical calculations that predicted eclipses and planetary conjunctions for inclusion in an almanac and ephemeris for the year of 1792.Bedini, 1999, pp. 147—188: "His First Almanac". To aid Banneker in his efforts to have his almanac published, Andrew Ellicott (who had been authoring almanacs and ephemerides of his own since 1780)(1) .
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She studied fluid mechanics for her Master's studies at the Pierre and Marie Curie University. She worked multiple jobs alongside her studies. Kébé worked on space debris during her PhD, specialising in modelling fragmentation events to monitor the movement of debris. She worked at the Pierre and Marie Curie University Paris Observatory in the Institute for Celestial Mechanics and Computation of Ephemerides.
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The Age of Exploration was in part enabled by a crucial navigational advances developed by the primarily Jewish Majorcan cartographic school as well as Abraham Zacuto's ephemerides. Zacuto, Royal Astronomer and Historian of Portugal, left Portugal rather than become Christian. Vasco da Gama even lent his name to his Jewish pilot Gaspar da Gama. Many Jews also worked as ship navigators.
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Agave macroacantha, the black-spined agave or large-thorned agave, is a species of succulent flowering plant in the family Asparagaceae naturally occurring in Oaxaca and also near the town of Tehuacan in the State of Puebla, Mexico.Zuccarini, Joseph Gerhard. Nova Acta Physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta 16(2): 676. 1833.
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612 in Explanatory Supplement to the Astronomical Almanac, ed. P K Seidelmann, 1992, confirming introduction of ET in the 1960 edition of the ephemerides. in accordance with the adopted ET proposal of 1948–52. ET, in turn, can now be seen (in light of modern results)See especially F R Stephenson (1997), and Stephenson & Morrison (1995), book and papers cited below.
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Georgij A. Krasinsky (February 19, 1939; Leningrad, USSR) – March 17, 2011) was a Russian astronomer active at the Institute of Applied Astronomy, Russian Academy of Science, St Petersburg. He was notable for research on planetary motions and ephemeris. Krasinsky was the president of IAU commission 4-DI on ephemerides during 2003-2006. The asteroid 5714 Krasinsky is named after him.
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Connaissance des Temps (1795) The Connaissance des temps (English: Knowledge of the Times) is an official yearly publication of astronomical ephemerides in France. Until just after the French Revolution, the title appeared as Connoissance des temps, and for several years afterwards also as Connaissance des tems. Since 1984 it has appeared under the title Ephémérides astronomiques: Annuaire du Bureau des longitudes.
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He was born in Padua, and completed studies in philosophy in Bologna in 1579. His father was Pasquale Magini, a citizen of Padua. Dedicating himself to astronomy, in 1582 he wrote Ephemerides coelestium motuum, translated into Italian the following year. In 1588 he was chosen over Galileo Galilei to occupy the chair of mathematics at the University of Bologna after the death of Egnatio Danti.
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This minor planet was named after the feminine form of the name "Roger", picked from the Lahrer Hinkender Bote, which was published in Lahr, southern Germany. A Hinkender Bote (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides.
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Satellite data is updated typically every 24 hours, with up to 60 days data loaded in case there is a disruption in the ability to make updates regularly. Typically the updates contain new ephemerides, with new almanacs uploaded less frequently. The Control Segment guarantees that during normal operations a new almanac will be uploaded at least every 6 days. Satellites broadcast a new ephemeris every two hours.
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He also discovered one of the earlier asteroids found, 29 Amphitrite, and the galaxies NGC 3, NGC 4 and NGC 15. He also did work in double stars, discovering NGC 30 in 1864. From 1883 to 1897 he worked at the Markree Observatory in Ireland where he was the second director appointed in its second period of operation. He made extensive ephemerides of solar system bodies.
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The first national astronomical ephemeris, Connaissance de Temps, was published in France in 1679. In 1767 came the Nautical Almanac and Astronomical Ephemeris, which is issued annually by the Royal Observatory at Greenwich.The Columbia Electronic Encyclopaedia, (Sixth Edition), Columbia University Press, 2011. There are different types of ephemerides, and a distinction needs to be made between those used for astronomy and those for astrology.
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Agnès Fienga is a French astronomer working at the Institut de Mécanique Céleste et de Calcul des Éphémérides. She is active in the field of planetary ephemerides generation and is member of the International Astronomical Union (IAU). She collaborated with Dr. E. Myles Standish in researches on the asteroids and their impact on the orbital motions. Fienga is also interested in testing gravitational theories from planetary motions.
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Title page of the Ephemerides Vindobonensem for 1806Triesnecker was born in Mallon, Kirchberg am Wagram, Austria. When he was 16 he joined the Society of Jesus. He studied philosophy in Vienna and mathematics at Tyrnau, then became a teacher. Following the suppression of the Jesuits in 1773, he moved to Graz to complete his studies in theology, and was ordained soon after his graduation.
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Casaubon's diary, Ephemerides, whose manuscript is preserved in the chapter library of Canterbury, was printed in 1850 by the Clarendon Press. It forms the most valuable record we possess of the daily life of a scholar, or man of letters, of the 16th century. He also corresponded with the translators of the King James Version of the Bible and helped resolve issues in the translation.
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R. Hide et al., "Topographic core-mantle coupling and fluctuations in the Earth's rotation" 1993. The mean solar second between 1750 and 1892 was chosen in 1895 by Simon Newcomb as the independent unit of time in his Tables of the Sun. These tables were used to calculate the world's ephemerides between 1900 and 1983, so this second became known as the ephemeris second.
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Though there is a lack of surviving material on Babylonian planetary theory, it appears most of the Chaldean astronomers were concerned mainly with ephemerides and not with theory. It had been thought that most of the predictive Babylonian planetary models that have survived were usually strictly empirical and arithmetical, and usually did not involve geometry, cosmology, or speculative philosophy like that of the later Hellenistic models, though the Babylonian astronomers were concerned with the philosophy dealing with the ideal nature of the early universe. Babylonian procedure texts describe, and ephemerides employ, arithmetical procedures to compute the time and place of significant astronomical events. More recent analysis of previously unpublished cuneiform tablets in the British Museum, dated between 350 and 50 BCE, demonstrates that Babylonian astronomers sometimes used geometrical methods, prefiguring the methods of the Oxford Calculators, to describe the motion of Jupiter over time in an abstract mathematical space.
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These early releases were distributed on magnetic tape. In the days before personal computers, computers were large and expensive, and numerical integrations such as these were run by large organizations with ample resources. The JPL ephemerides prior to DE405 were integrated on a Univac mainframe in double precision. For instance, DE102, which was created in 1977, took six million steps and ran for nine days on a Univac 1100/81. DE405 was integrated on a DEC Alpha in quadruple precision.See Standish and Williams in the Sources In the 1970s and early 1980s, much work was done in the astronomical community to update the astronomical almanacs from the theoretical work of the 1890s to modern, relativistic theory. From 1975 through 1982, six ephemerides were produced at JPL using the modern techniques of least-squares adjustment of numerically-integrated output to high precision data: DE96 in Nov. 1975, DE102 in Sep.
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As UT is thus slightly irregular in its rate, astronomers introduced Ephemeris Time, which has since been replaced by Terrestrial Time (TT). Because Universal Time is determined by the Earth's rotation, which drifts away from more precise atomic-frequency standards, an adjustment (called a leap second) to this atomic time is needed since () 'broadcast time' remains broadly synchronised with solar time. Thus, the civil broadcast standard for time and frequency usually follows International Atomic Time closely, but occasionally step (or "leap") in order to prevent them from drifting too far from mean solar time. Barycentric Dynamical Time (TDB), a form of atomic time, is now used in the construction of the ephemerides of the planets and other solar system objects, for two main reasons.. Strictly speaking, a major producer of ephemerides, the Jet Propulsion Laboratory, uses a time scale they derive, Teph, which is functionally equivalent to TDB.
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Thirty-five years after his initial application, but still during his administration, this project was finally achieved. Francisco J. Duarte The physicist and mathematician Francisco J. Duarte assumed the directorship in 1936. He made constant requests for funds, but these were routinely rejected and he was unable to obtain modern instruments suitable for astronomical observations. Duarte continued the collections of meteorological data and published annual ephemerides in 1940 and 1941.
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From 2015 onwards this ephemeris is utilized in Astronomical Almanac. Beginning with this release only Mars' Barycenter was included due to the small masses of its moons Phobos and Deimos which create a very small offset from the planet's center. The complete ephemerides files is 128 megabytes but several alternative versions have been made available by JPL DE432 was created April 2014. It includes librations but no nutations.
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In astronomy and celestial navigation, an ephemeris (plural: ephemerides) gives the trajectory of naturally occurring astronomical objects as well as artificial satellites in the sky, i.e., the position (and possibly velocity) over time. The etymology is and .. Historically, positions were given as printed tables of values, given at regular intervals of date and time. The calculation of these tables was one of the first applications of mechanical computers.
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39) Among the aims of the Bolsheviks was to drive through eastern and central Europe and support the Revolutions in Germany and Austria- Hungary.(Davies, p. 29) The Bolshevik forces did not anticipate serious opposition on the way and saw the states of Poland, Belarus and Lithuania as mere ephemerides, unable to defend their own "temporary" borders. However, it is unlikely that the Soviets really expected to reach the Vistula.
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IX Special perturbations can be applied to any problem in celestial mechanics, as it is not limited to cases where the perturbing forces are small. Once applied only to comets and minor planets, special perturbation methods are now the basis of the most accurate machine-generated planetary ephemerides of the great astronomical almanacs.See, for instance, Jet Propulsion Laboratory Development Ephemeris. Special perturbations are also used for modeling an orbit with computers.
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Peirce 1853 The same table appears in Tables of Mercury by Joseph Winlock, without any other Julian days.Winlock 1864 The national ephemerides started to include a multi-year table of Julian days, under various names, for either every year or every leap year beginning with the French Connaissance des Temps in 1870 for 2,620 years, increasing in 1899 to 3,000 years.Connaissance des Temps 1870, pp. 419–424; 1899, pp.
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Baker-Nunn satellite tracking camera. Whipple envisioned a global network of specially designed instruments that could track and photograph satellites. This network, aided by a corps of volunteer satellite spotters and a computer at the MIT Computation Center, would establish ephemerides – predictions of where a satellite will be at particular times. The instruments at these stations were eventually designed by Dr. James G. Baker and Joseph Nunn and hence known as Baker-Nunn cameras.
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The L5 CNAV data includes SV ephemerides, system time, SV clock behavior data, status messages and time information, etc. The 50 bit/s data is coded in a rate 1/2 convolution coder. The resulting 100 symbols per second (sps) symbol stream is modulo-2 added to the I5-code only; the resultant bit-train is used to modulate the L5 in-phase (I5) carrier. This combined signal is called the L5 Data signal.
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It had been found that five different types of numerations were used in the Sinhala language at the time of the invasion of the Kandyan kingdom by the British. Out of the five types of numerations, two sets of numerations were in use in the twentieth century mainly for astrological calculations and to express traditional year and dates in ephemerides. The five types or sets of numerals or numerations are listed below.
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At Giessen Dillenius wrote botanical papers for the Ephemerides naturae curiosorum. He printed, in 1719, his flora of the university's surroundings, a Catalogus plantarum sponte circa Gissam nascentium, which was illustrated with figures drawn and engraved by his own hand, and contained descriptions of new species. In 1724 Dillenius published the third edition of John Ray's Synopsis Methodica Stirpium Britannicarum. It incorporated plant species discovered by Samuel Brewer, and work on mosses by Adam Buddle.
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By the 4th century, their mathematical methods had progressed enough to calculate future planetary positions with reasonable accuracy, at which point extensive ephemerides began to appear.Holden (1996) p.9. Babylonian astrology developed within the context of divination. A collection of 32 tablets with inscribed liver models, dating from about 1875 BC, are the oldest known detailed texts of Babylonian divination, and these demonstrate the same interpretational format as that employed in celestial omen analysis.
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Ceyssens was born in Wijchmaal, Belgium, on 8 October 1902. In 1921 he entered the Order of St Francis, and in 1927 he was ordained priest. He followed some history classes at the Catholic University of Louvain in 1929–31, and in 1934 was a student at the Faculty of Church History of the Gregorian University in Rome.Mathijs Lamberigts, "In memoriam Lucien Ceyssens (1902-2001)", Ephemerides theologicae Lovanienses 77 (2001), pp. 537-540.
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Discovery images of Siarnaq taken by the CFHT in September 2000 ephemerides of 13 irregular satellites relative to Saturn in 2001. Siarnaq is located at the upper left from the center. Siarnaq was discovered by Canadian astronomers Brett Gladman and John Kavelaars at the Mauna Kea Observatory on 23 September 2000. The discovery of Siarnaq formed part of an observational campaign, coordinated by Gladman in late 2000, to search for distant irregular satellites around Saturn.
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The precession of the equinox The equinox moves, in the sense that as time progresses it is in a different location with respect to the distant stars. Consequently, star catalogs over the years, even over the course of a few decades, will list different ephemerides. This is due to precession and nutation, both of which can be modeled, as well as other minor perturbing forces which can only be determined by observation and are thus tabulated in astronomical almanacs.
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Bedini, 1972, pp. 172—173. Banneker's Pennsylvania, Delaware, Maryland and Virginia Almanack and Ephemeris, for the Year of our Lord, 1792 was the first in a six-year series of almanacs and ephemerides that printers agreed to publish and sell. At least 28 editions of the almanacs, some of which appeared during the same year, were printed in seven cities in five states: Baltimore; Philadelphia; Wilmington, Delaware; Alexandria, Virginia; Petersburg, Virginia; Richmond, Virginia; and Trenton, New Jersey.
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An astronomical constant is any of several physical constants used in astronomy. Formal sets of constants, along with recommended values, have been defined by the International Astronomical Union (IAU) several times: in 1964Resolution No.4 of the XIIth General Assembly of the International Astronomical Union, Hamburg, 1964. and in 1976Resolution No. 1 on the recommendations of Commission 4 on ephemerides in the XVIth General Assembly of the International Astronomical Union, Grenoble, 1976. (with an update in 1994).
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Mally was discovered on 19 March 1931, by German astronomer Max Wolf at Heidelberg Observatory in southwest Germany. Soon after its initial discovery, it became one of few well known lost minor planets for over 55 years. In 1986, Mally was rediscovered by astronomers Lutz Schmadel, Richard Martin West and Hans-Emil Schuster, who remeasured the original discovery plates and computed alternative search ephemerides. This allowed them to find the body very near to its predicted position.
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Jacques Laskar (born 28 April 1955 in Paris) is a French astronomer. He is a research director at the French National Centre for Scientific Research (CNRS), and a member of Astronomy and dynamical systems of the Institute of Celestial Mechanics and Computation of Ephemerides (French: IMCCE) of the Paris Observatory. He received the CNRS Silver medal in 1994 and the Milutin Milankovic Medal in 2019. Since 2003, he is a member of the French Academy of Sciences.
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A Java applet is available and provided as a 3D orbit visualization tool. The applet was implemented using unreliable 2-body methods, and hence should not be used for determining accurate long- term trajectories (over several years or decades) or planetary encounter circumstances. For accurate ephemerides use the JPL Horizons On-Line Ephemeris System that handles the n-body problem using numerical integration. The Java applet is available by adding ";orb=1" to the end of the body's URL.
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The Toledan Tables, or Tables of Toledo, were astronomical tables which were used to predict the movements of the Sun, Moon and planets relative to the fixed stars. They were completed around year 1080 by a group of Arabic astronomers at Toledo, Spain. They had started as preexisting Arabic tables made elsewhere, and were numerically adjusted to be centered on the location of Toledo. In modern English astronomy, tables of movements of astronomical bodies are called ephemerides.
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Ephemerides of the planet Saturn also sometimes contain the apparent inclination of its ring. Celestial navigation serves as a backup to the Global Positioning System. Software is widely available to assist with this form of navigation; some of this software has a self-contained ephemeris. When software is used that does not contain an ephemeris, or if no software is used, position data for celestial objects may be obtained from the modern Nautical Almanac or Air Almanac.
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In Babylonian astronomical diaries, a planet position was generally given with respect to a zodiacal sign alone, less often in specific degrees within a sign. When the degrees of longitude were given, they were expressed with reference to the 30° of the zodiacal sign, i.e., not with a reference to the continuous 360° ecliptic. In astronomical ephemerides, the positions of significant astronomical phenomena were computed in sexagesimal fractions of a degree (equivalent to minutes and seconds of arc).
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For example, the Astronomical Almanac uses TT for its tables of positions (ephemerides) of the Sun, Moon and planets as seen from Earth. In this role, TT continues Terrestrial Dynamical Time (TDT or TD),TT is equivalent to TDT, see IAU conference 1991, Resolution A4, recommendation IV, note 4. which in turn succeeded ephemeris time (ET). TT shares the original purpose for which ET was designed, to be free of the irregularities in the rotation of Earth.
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A definition of a terrestrial time standard was adopted by the International Astronomical Union (IAU) in 1976 at its XVI General Assembly, and later named Terrestrial Dynamical Time (TDT). It was the counterpart to Barycentric Dynamical Time (TDB), which was a time standard for Solar system ephemerides, to be based on a dynamical time scale. Both of these time standards turned out to be imperfectly defined. Doubts were also expressed about the meaning of 'dynamical' in the name TDT.
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Newcomb's Tables of the Sun (full title Tables of the Motion of the Earth on its Axis and Around the Sun) is a work by the American astronomer and mathematician Simon Newcomb, published in volume VI of the serial publication Astronomical Papers Prepared for the Use of the American Ephemeris and Nautical Almanac.Simon Newcomb, Tables of the Four Inner Planets, 1-169. The work contains Newcomb's mathematical development of the position of the Earth in the Solar System, which is constructed from classical celestial mechanics as well as centuries of astronomical measurements. The bulk of the work, however, is a collection of tabulated precomputed values that provide the position of the sun at any point in time. Newcomb's Tables were the basis for practically all ephemerides of the Sun published from 1900 through 1983, including the annual almanacs of the U.S. Naval Observatory and the Royal Greenwich Observatory. The physical tables themselves were used by the ephemerides from 1900 to 1959, computerized versions were used from 1960 to 1980, and evaluations of the Newcomb's theories were used from 1981 to 1983.
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Elementi della geometria piana e solida e della trigonometria, 1755 Manfredi's scientific work was impressive. On 29 November 1707 Manfredi and Vittorio Francesco Stancari discovered the comet C/1707 W1. Among his scientific works are Ephemerides motuum coelestium (1715–1725), De transitu Mercurii per solem anno 1723 (1724), De gnomone meridiano bononiensi (1736) and Instituzioni astronomiche (1749), a posthumous work. The asteroid 13225 Manfredi was named in honour of Eustachio Manfredi and his two brothers Gabriele Manfredi and Eraclito Manfredi.
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Frisius had in a letter written in 1555 urged Stadius not to be afraid of being accused of believing in a moving earth and a stationary sun (i.e. the theory of Copernicus) or of abandoning the medieval Alfonsine Tables in favor of his own observations. In this letter Frisius further wrote that the system devised by Copernicus gave a better understanding of planetary distances, as well as of certain features of retrograde motion. Frisius' letter was published in several editions of the Ephemerides.
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Philipp Jakob Sachs as depicted in Miscellanea Curiosa Medico-Physica Academiae Naturae Curiosorum (1676) Philipp Jakob Sachsvon Löwenheim, or Lewenhaimb, Lewenheimb (26 August 1627, Breslau- 7 January 1672, Breslau) was a German physician, naturalist, and editor of Ephemerides Academiae naturae curiosorum, the first ever learned journal in the field of medicine and natural history. He was a state physician in Breslau, and one of the founders of the Academia Naturae Curiosorum (Leopoldina). His works include the 1665 Gammarologia, on crabs.
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Ephemeris time was a first application of the concept of a dynamical time scale, in which the time and time scale are defined implicitly, inferred from the observed position of an astronomical object via the dynamical theory of its motion.B Guinot and P K Seidelmann (1988), at p.304-5. # a modern relativistic coordinate time scale, implemented by the JPL ephemeris time argument Teph, in a series of numerically integrated Development Ephemerides. Among them is the DE405 ephemeris in widespread current use.
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Baigent (1994) p.71. At this time Babylonian astrology was solely mundane, and prior to the 7th century BC the practitioners' understanding of astronomy was fairly rudimentary. Because of their inability to accurately predict future celestial phenomena and planetary movement very far in advance, interpretations were done as the phenomena occurred or slightly before. By the 4th century, however, their mathematical methods had progressed enough to calculate future planetary positions with reasonable accuracy, at which point extensive ephemerides began to appear.
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Alexander's headquarters included a historical archives unit. Of lowest rank were clerks whose task it was to collect information about the day's operations and events, probably in the form of written notes. This information was reported to an officer in charge of keeping the ephemerides, “Day Journal,” a record of the army's doings similar to a ship's log. For most of Alexander's expedition, the officer was Diodotus of Erythrae, who remained of such low rank that he is only mentioned once anywhere.
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Simon Newcomb (12 March 1835-11 July 1909) was a Canadian-American astronomer who revised Peter Andreas Hansen's table of lunar positions. In 1877, assisted by George William Hill, he recalculated all the major astronomical constants. After 1884, he conceived with A. M. W. Downing a plan to resolve much international confusion on the subject. By the time he attended a standardisation conference in Paris, France in May 1886, the international consensus was that all ephemerides should be based on Newcomb's calculations.
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The close conjunction of Jupiter and Saturn in 1563— which was observed by Tycho Brahe and led him to note the inaccuracy of existing ephemerides and to begin his own program of astronomical measurements—occurred in Cancer not far from Praesepe. In Greek mythology, Cancer is identified with the crab that appeared while Heracles fought the many-headed Hydra. Hercules slew the crab after it bit him in the foot. Afterwards, the goddess Hera, an enemy of Heracles, placed the crab among the stars.
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At the local meridian the Sun reaches its highest point on its daily arc across the sky. In 1874 the British Association for the Advancement of Science introduced the CGS (centimetre/gramme/second system) combining fundamental units of length, mass and time. The second is "elastic", because tidal friction is slowing the earth's rotation rate. For use in calculating ephemerides of celestial motion, therefore, in 1952 astronomers introduced the "ephemeris second", currently defined as The CGS system has been superseded by the Système international.
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An invariable second (the "ephemeris second") had been defined, use of which removed the errors in ephemerides resulting from the use of the variable mean solar second as the time argument. In 1960 this ephemeris second was made the basis of the "coordinated universal time" which was being derived from atomic clocks. It is a specified fraction of the mean tropical year as at 1900 and, being based on historical telescope observations, corresponds roughly to the mean solar second of the early nineteenth century.
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The Commentarii Principis were the register of the official acts of the emperor. They contained the decisions, favourable or unfavourable, in regard to certain citizens; accusations brought before him or ordered by him; and lists of persons in receipt of special privileges. These must be distinguished from the commentarii diurni, a daily court-journal. At a later period records called ephemerides were kept by order of the emperor; these were much used by the collection of biographies known as Scriptores Historiae Augustae (see Augustan History).
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Henk Jan de Jonge, a specialist in Erasmian studies, stated that there is no explicit evidence that supports this frequently made assertion concerning a specific promise made by Erasmus. The real reason to include the Comma by Erasmus, was his care for his good name and for the success of his Novum Testamentum.Henk Jan de Jonge, Erasmus and the Comma Johanneum, Ephemerides Theologicae Lovanienses 1980, p. 385 In this edition Erasmus, after using Codex Montfortianus, misprinted εμαις for εν αις in Apocalypse 2:13.
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A fundamental ephemeris of the Solar System is a model of the objects of the system in space, with all of their positions and motions accurately represented. It is intended to be a high-precision primary reference for prediction and observation of those positions and motions, and which provides a basis for further refinement of the model. It is generally not intended to cover the entire life of the Solar System; usually a short-duration time span, perhaps a few centuries, is represented to high accuracy. Some long ephemerides cover several millennia to medium accuracy.
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Graphic rapresentation of JPL Horizons On-Line Ephemeris System output values JPL Horizons On-Line Ephemeris System provides easy access to key Solar System data and flexible production of highly accurate ephemerides for Solar System objects. Osculating elements at a given epoch are always an approximation to an object's orbit (i.e. an unperturbed conic orbit or a "two-body" orbit). The real orbit (or the best approximation to such) considers perturbations by all planets, a few of the larger asteroids, a few other usually small physical forces, and requires numerical integration.
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Against the wishes of his wife's family, Pestalozzi gained the support of philosopher Isaak Iselin of Basel, who published it in Die Ephemerides, a periodical devoted to social and economic questions. The publication led to subscriptions and loans free of interest. The new foundation had a short period of apparent prosperity, but after a year Pestalozzi's old faults again led the institution to near ruin. An appeal for public support in 1777 brought much-needed help, and Pestalozzi contributed to the periodical a series of letters on the education of the poor.
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Though the masses had not yet been adopted by the IAU. The ephemerides were created to support the arrivals of the MER and Cassini spacecraft. DE411See, for instance, which compares DE413 output with DE411. was widely cited in the astronomical community, but not publicly released by JPL DE412See, for instance, which references DE412. was widely cited in the astronomical community, but not publicly released by JPL DE413 was released in 2004 with updated ephemeris of Pluto in support of the occultation of a star by its satellite Charon on 11 Jul 2005.
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From 1859 to 1863 he was professor of physics at the faculty of mathematics and director of the physics department. In the same period he was appointed professor of astronomy in the faculty od philosophy. He died in the city of Padua, in the Veneto, northern Italy, and was succeeded by Michez Jacopo (1839-1873). His work summarizes 61 articles written in 14 years of study focused on the observation of asteroids, comets, eclipses, the calculation of planetary orbits with respect to the action of the disturbing planets of the solar system and ephemerides.
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In Lugano, there was a Corrier zoppo, o sia Mercurio storico e politico from 1756 to 1762. The almanachs contained calendars with both Catholic and Protestant feast days, the dates of important fairs and astronomical ephemerides, and anecdotal accounts of events of the preceding years sections accompanied with illustrations. In Vevey, a tradition developed of depicting a real-life leg amputee on the cover; the currently serving "limping messenger" is one Jean-Luc Sansonnens of Fribourg (b. 1969) who lost his leg in a motorcycle accident in 1988.
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Ratdolt's edition of the Tabule directionum profectionumque of Regiomontanus, printed in 1490, has corrections by Engel. In 1491 Ratdolt printed Engel's edition of the Decem tractatus astronomiae of the thirteenth-century mathematician and astrologer Guido Bonatti of Forlì. The Ephemerides coelestium motuum usque ad annum 1500 of 1494 was printed in Vienna by Johannes Winterburger, the first Viennese printer, who also printed the undated Almanach novum atque collectum … super anno domini 1510. Engel's brief treatise on the plague, Tractat von der Pestilentz Joanni Engel … was printed posthumously in Augsburg by and , on 4 November 1518.
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The first edition of Schott's Almanac was published in Britain in 2005, followed by yearly editions published in Britain, America, and Germany until 2010. The Almanacs shared the same look and feel as the Miscellanies – but were substantially longer and larger. Each edition was different, although some content was shared or adapted. The British edition had sections on The World; Society; Media & Celebrity; Music & Movies; Books & Arts; Science & Technology; Parliament & Politics; Form & Faith; The Establishment; Sport; and an Ephemerides section that contains traditional almanac information on dates, moon phases, and the season.
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The modern astrological symbol for Vesta, ⚶, was created by Eleanor Bach, who is credited with pioneering the use of the Big Four asteroids with the publication of her Ephemerides of the Asteroids. Bach's symbol for Vesta is a simplified version of other representations of Vesta's altar. The original form of the symbol for Vesta, Vesta, was created by German mathematician Carl Friedrich Gauss. Olbers, having previously discovered and named one new planet (as the asteroids were then classified), gave Gauss the honor of naming his newest discovery.
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But even that was unreliable at times because a pilot would need calm waters in order to acquire a reading. Eventually it was used together with the astrolabe, which became a critical piece of equipment for navigation after Martin Cortes de Albacar published his Art. Because it could be used day or night, in rough or calm seas, it was cross referenced with the quadrant in order to gain the most accurate reading possible. Finally, the nocturnal and its accompanied values in the ephemerides granted sailors the ability to plot longitude on the open ocean.
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M102 was observed by Méchain, who communicated his notes to Messier. Méchain later concluded that this object was simply a re-observation of M101, though some sources suggest that the object Méchain observed was the galaxy NGC 5866 and identify that as M102. Messier's final catalogue was included in the Connaissance des Temps pour l'Année 1784 ("Knowledge of the Times for the Year 1784"), the French official yearly publication of astronomical ephemerides. Messier lived and did his astronomical work at the Hôtel de Cluny (now the Musée national du Moyen Âge), in Paris, France.
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Ephemeris time (ET), adopted as standard in 1952, was originally designed as an approach to a uniform time scale, to be freed from the effects of irregularity in the rotation of the earth, "for the convenience of astronomers and other scientists", for example for use in ephemerides of the Sun (as observed from the Earth), the Moon, and the planets. It was proposed in 1948 by G M Clemence.G M Clemence (1948). From the time of John Flamsteed (1646–1719) it had been believed that the Earth's daily rotation was uniform.
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Standalone GPS provides first position in approximately 30–40 seconds. A standalone GPS needs orbital information of the satellites to calculate the current position. The data rate of the satellite signal is only 50 bit/s, so downloading orbital information like ephemerides and the almanac directly from satellites typically takes a long time, and if the satellite signals are lost during the acquisition of this information, it is discarded and the standalone system has to start from scratch. In A-GPS, the network operator deploys an A-GPS server, a cache server for GPS data.
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Wolf, A History of Science, Technology and Philosophy, pp. 140–41; Pannekoek, A History of Astronomy, p 252 As a spin-off from the Rudolphine Tables and the related Ephemerides, Kepler published astrological calendars, which were very popular and helped offset the costs of producing his other work—especially when support from the Imperial treasury was withheld. In his calendars—six between 1617 and 1624—Kepler forecast planetary positions and weather as well as political events; the latter were often cannily accurate, thanks to his keen grasp of contemporary political and theological tensions.
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He was elected a Foreign Fellow of the Royal Society of London in 1821, and a Fellow of the Royal Society of Edinburgh in 1822. Schumacher was chiefly occupied with the publication of Ephemerides (11 parts, 1822–1832) and of the journal Astronomische Nachrichten (founded by himself in 1821 and still being published), of which he edited thirty-one volumes. In 1827 he was elected member of the Royal Swedish Academy of Sciences, and in 1829 he won the Gold Medal of the Royal Astronomical Society. Schumacher was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1834.
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Earth's rotation period relative to the Sun (its mean solar day) consists of 86,400 seconds of mean solar time, by definition. Each of these seconds is slightly longer than an SI second because Earth's solar day is now slightly longer than it was during the 19th century, due to tidal deceleration. The mean solar second between 1750 and 1892 was chosen in 1895 by Simon Newcomb as the independent unit of time in his Tables of the Sun. These tables were used to calculate the world's ephemerides between 1900 and 1983, so this second became known as the ephemeris second.
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In 1988, the Efe Data service was launched, the first Spanish news data bank, and in March of that same year the Efe Foundation was created to promote research, development and study of information and technology, as well as the granting of training scholarships for students in any of the branches of Information Sciences. In 1989, Efe began distributing its information services to its customers via satellites. This same year the 50th anniversary of the Agencia EFE was celebrated with an itinerant graphic exhibition called Ephemerides. The Press Association of Madrid awards the Rodríguez Santamaría Award to Efe for its work.
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Annual almanacs are published listing the derived values and methods of use. Until 1983, the Astronomical Almanac's angular value of the mean obliquity for any date was calculated based on the work of Newcomb, who analyzed positions of the planets until about 1895: : where is the obliquity and is tropical centuries from B1900.0 to the date in question. From 1984, the Jet Propulsion Laboratory's DE series of computer- generated ephemerides took over as the fundamental ephemeris of the Astronomical Almanac. Obliquity based on DE200, which analyzed observations from 1911 to 1979, was calculated: : where hereafter is Julian centuries from J2000.0.
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The ephemerides are updated every 30 minutes using data from the Ground Control segment; they use Earth Centred Earth Fixed (ECEF) Cartesian coordinates in position and velocity, and include lunisolar acceleration parameters. The almanac uses modified Keplerian elements and is updated daily. The more accurate high-precision signal is available for authorized users, such as the Russian military, yet unlike the US P(Y) code, which is modulated by an encrypting W code, the GLONASS restricted-use codes are broadcast in the clear using only security through obscurity. The details of the high-precision signal have not been disclosed.
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Rev. Nehemiah Strong (24 February 1729 (N.S.) – 13 August 1807) was an American astronomer and meteorologist who was the first Professor of Mathematics and Natural Philosophy at Yale College from 1770The post was created in September 1770 for him (Franklin Bowditch Dexter, Biographical Sketches of the Graduates of Yale College with Annals 1896, s.v. "Strong, Nehemiah"). and produced a series of annual ephemerides, the astronomical element in almanacs, which were printed in Hartford, Connecticut, and in New Haven.Alfred Carlos Bates, "Check List of Connecticut Almanacs, 1709–1850: With Introduction and Notes" Proceedings of the American Antiquarian Society 24(1): 93-215. 1914.
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He completed his doctorate in sacred theology at the Pontifical University of St. Thomas Aquinas Angelicum in 1938 with a dissertation entitled De liturgia eiusque momento in Concilio Tridentino. Accessed 30 December 2014 He spent ten years in parish work in a suburb of Rome. In 1947 Bugnini became involved in the production of the missionary publications of his order and became the first editor of Ephemerides Liturgicæ, a scholarly journal dedicated to the reform of the Catholic liturgy. Starting in 1949, he taught Liturgical Studies at the Pontifical Urban College (now the Pontifical Urban University).
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The equinox of the coordinate system must be given. It is, in nearly all cases, either the actual equinox (the equinox valid for that moment, often referred to as "of date" or "current"), or that of one of the "standard" equinoxes, typically J2000.0, B1950.0, or J1900. Star maps almost always use one of the standard equinoxes. Scientific ephemerides often contain further useful data about the moon, planet, asteroid, or comet beyond the pure coordinates in the sky, such as elongation to the Sun, brightness, distance, velocity, apparent diameter in the sky, phase angle, times of rise, transit, and set, etc.
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During his voyage to the southern hemisphere as a passenger on the vessel Le Glorieux, captained by the noted hydrographer Jean-Baptiste d'Après de Mannevillette, Lacaille became conscious of the difficulties in determining positions at sea. On his return to Paris he prepared the first set of tables of the Moon's position that was accurate enough to use for determining time and longitude by the method of 'Lunars' (Lunar distances) using the orbital theory of Clairaut. Lacaille was in fact an indefatigable calculator. Apart from constructing astronomical ephemerides and mathematical tables, he calculated a table of eclipses for 1800 years.
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From the 17th century to the late 19th century, planetary ephemerides were calculated using time scales based on the Earth's rotation: usually the mean solar time of one of the principal observatories, such as Paris or Greenwich. After 1884, mean solar time at Greenwich became a standard, later named Universal Time (UT). But in the later 19th and early 20th centuries, with the increasing precision of astronomical measurements, it began to be suspected, and was eventually established, that the rotation of the Earth (i.e. the length of the day) showed irregularities on short time scales, and was slowing down on longer time scales.
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Gingerich and his wife, Miriam, have been married for over 60 years. They have three sons, Mark, Peter, and Jonathan, as well as three grandchildren named Philip, Yasmin, and Dilara. They enjoy traveling, photography, and collecting both sea shells and rare books. Though they do not own a copy of the first edition of De revolutionibus (they own two second editionsGingerich, O.:The Book Nobody Read, Walker & Co., 2004.), his collection of sixteenth- and seventeenth-century ephemerides (books that give day-by-day positions of the planets) recently surpassed the runner-up, the Bibliothèque Nationale in Paris.
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Edmund Spenser, in his Teares of the Muses (1591), laments the same evils, if only in general terms. The tract was dedicated to Sir Philip Sidney, who seems to have resented being connected with it, writing to Gabriel Harvey (16 October 1579) of the dedication that the author "was for hys labor scorned." Gosson dedicated, however, a second tract, The Ephemerides of Phialo ... and A Short Apologie of the Schoole of Abuse, to Sidney on 28 October 1579. Gosson's attack on poets seems to have had a large share in inducing Sidney to write his Apologie for Poetrie, which probably dates from 1581.
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He both edited and submitted to the Connaissance des Temps, the astronomical ephemerides used by many navigators, geographers and astronomers of the time. He developed a method of calculating tables to determine the phases of the moon over much longer durations than before (over 30 centuries). Presented at the French Academy of Sciences, it earned admission as a Free Academician on December 13, 1847. This work, in concert with a Xia dynasty document preserved in a Chinese classic, the Book of Documents, allowed the calculation of the date of a solar eclipse recorded during the reign of Zhong Kang.
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In the years following the completion of Astronomia Nova, most of Kepler's research was focused on preparations for the Rudolphine Tables and a comprehensive set of ephemerides (specific predictions of planet and star positions) based on the table (though neither would be completed for many years). He also attempted (unsuccessfully) to begin a collaboration with Italian astronomer Giovanni Antonio Magini. Some of his other work dealt with chronology, especially the dating of events in the life of Jesus, and with astrology, especially criticism of dramatic predictions of catastrophe such as those of Helisaeus Roeslin.Caspar, Kepler, pp.
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Given his strong interest in astronomy, Oriani was appointed on the staff of the Observatory of Brera in Milan in 1776, becoming assistant astronomer in 1778 and director in 1802. In 1778 he began publishing various in-depth dissertations on astronomical objects, the Effemeridi di Milano (Ephemerides of Milan). A very capable astronomer, Oriani's work began to attract considerable attention. His research in the areas of astronomic refraction, the obliquity of the ecliptic, and orbital theory were of considerable noteworthiness in themselves; but his greatest achievement was his detailed research of the planet Uranus, which had been discovered by Sir William Herschel in 1781.
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This minor planet was named in honor of Russian astronomer Samuel Gdalevich Makover (1908–1970), who studied extensively the orbit of Encke's Comet (referred to as Comet Encke-Backlund in Russia), and pioneered in the use of electronic calculators for computing planetary perturbations and orbit improvements. He was head of the Institute of Theoretical Astrophysics's (ITA) department of minor planets and comets, and editor of the annual volume of Minor Planet Ephemerides. He was also a vice-president of IAU's commission 20, Positions & Motions of Minor Planets, Comets & Satellites, in the 1960s. The official was published by the Minor Planet Center on 25 September 1971 ().
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Starting from 1624, Remus Quietanus published regularly (probably every year) calendars containing the ephemerides of planets and weather forecasts. The first known edition is “Neuer Schreibkalender, auff das Jubel Jahr 1625(…)“, Basel 1624, (New Calendar for the Year of Grace 1625(…) Containing the Real Course of the Sun and the Moon, the Sunrise and Sunset, the Lunar Phase and the Planetary Configurations, the Solar and Lunar Eclipses and the Probable Weather Conditions). It is presented in the form of a diary. Extant copies or references of the Schreibkalender can be found for the years of 1624, 1625, 1626, 1627, 1629, 1630, 1631, 1638, 1641, 1650.
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Hipparchus probably compiled a list of Babylonian astronomical observations; G. J. Toomer, a historian of astronomy, has suggested that Ptolemy's knowledge of eclipse records and other Babylonian observations in the Almagest came from a list made by Hipparchus. Hipparchus's use of Babylonian sources has always been known in a general way, because of Ptolemy's statements. However, Franz Xaver Kugler demonstrated that the synodic and anomalistic periods that Ptolemy attributes to Hipparchus had already been used in Babylonian ephemerides, specifically the collection of texts nowadays called "System B" (sometimes attributed to Kidinnu).Franz Xaver Kugler, Die Babylonische Mondrechnung ("The Babylonian lunar computation"), Freiburg im Breisgau, 1900.
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This academy was the product of the notable 18th century movement in liturgical studies which owed so much to the great theologian and liturgist, Benedict XIV (1745-8). Disbanded in the time of the Revolution, the Academy was reorganized by the Lazarists, under Gregory XV (1840), and received a cardinal-protector. It continues its work under the direction of the Lazarists, and holds frequent conferences in which liturgical and cognate subjects are treated from the historical and the practical point of view. It is located in the Lazarist house, and its proceedings are, since 1886, published in the Lazarist monthly known as "Ephemerides Liturgicae" (Liturgical Diary).
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Major astronomers who practised as court astrologers included Tycho Brahe in the royal court of Denmark, Johannes Kepler to the Habsburgs and Galileo Galilei to the Medici. The astronomer and spiritual astrologer Giordano Bruno was burnt at the stake for heresy in Rome in 1600. Ephemerides with complex astrological calculations, and almanacs interpreting celestial events for use in medicine and for choosing times to plant crops, were popular in Elizabethan England. In 1597, the English mathematician and physician Thomas Hood made a set of paper instruments that used revolving overlays to help students work out relationships between fixed stars or constellations, the midheaven, and the twelve astrological houses.
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In 1877 he became director of the Nautical Almanac Office where, ably assisted by George William Hill, he embarked on a program of recalculation of all the major astronomical constants. Despite fulfilling a further demanding role as professor of mathematics and astronomy at Johns Hopkins University from 1884, he conceived with A. M. W. Downing a plan to resolve much international confusion on the subject. By the time he attended a standardisation conference in Paris, France, in May 1896, the international consensus was that all ephemerides should be based on Newcomb's calculations—Newcomb's Tables of the Sun. A further conference as late as 1950 confirmed Newcomb's constants as the international standard.
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The changing names and contents of related titles in the series are summarised as follows. (The issue years mentioned below are those for which the data in the relevant issue were calculated—and the issues were in practice published in advance of the year for which they were calculated, at different periods of history, anything from 1 to 5 years in advance). (For many years, official nautical almanacs and astronomical ephemerides in the UK and the USA had a linked history, and they became merged in both titles and contents in 1981.) In the UK, the official publications have been:ESAE 1961, see esp. sect. 1B.
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Indeed, the International Committee for Weights and Measures (CIPM) notes that "its definition applies only within a spatial extent sufficiently small that the effects of the non-uniformity of the gravitational field can be ignored". As such, the metre is undefined for the purposes of measuring distances within the Solar System. The 1976 definition of the astronomical unit was incomplete because it did not specify the frame of reference in which time is to be measured, but proved practical for the calculation of ephemerides: a fuller definition that is consistent with general relativity was proposed, and "vigorous debate" ensued and also p. 91, Summary and recommendations.
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An engraving by Albrecht Dürer featuring Mashallah, from the title page of the De scientia motus orbis (Latin version with engraving, 1504). As in many medieval illustrations, the compass here is an icon of religion as well as science, in reference to God as the architect of creation. For a long time the funding from astrology supported some astronomical research, which was in turn used to make more accurate ephemerides for use in astrology. In Medieval Europe the word Astronomia was often used to encompass both disciplines as this included the study of astronomy and astrology jointly and without a real distinction; this was one of the original Seven Liberal Arts.
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For the next two and a half centuries, Io remained an unresolved, 5th-magnitude point of light in astronomers' telescopes. During the 17th century, Io and the other Galilean satellites served a variety of purposes, including early methods to determine longitude, validating Kepler's third law of planetary motion, and determining the time required for light to travel between Jupiter and Earth. Based on ephemerides produced by astronomer Giovanni Cassini and others, Pierre-Simon Laplace created a mathematical theory to explain the resonant orbits of Io, Europa, and Ganymede. This resonance was later found to have a profound effect on the geologies of the three moons.
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TDT and TDB were defined in a series of resolutions at the same 1976 meeting of the International Astronomical Union. It was eventually realized that TDB was not well defined because it was not accompanied by a general relativistic metric and because the exact relationship between TDB and TDT had not been specified. (It was also later criticized as being not physically possible in exact accordance with its original definition: among other things the 1976 definition excluded a necessary small offset for the initial epoch of 1977.)E M Standish (1998), "Time scales in the JPL and CfA ephemerides", Astronomy and Astrophysics, v.336 (1998), p.381-384.
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In his work Phaenomenon singulare (1609) Kepler had described what he took to be the transit of Mercury, observed on 29 May 1607. However, after Michael Maestlin pointed out Galileo's work to him, he corrected himself in 1617 in his Ephemerides, recognising long after the event that what he had seen was sunspots. Welser sent Kepler a copy of Scheiner's first three Apelles letters, and Kepler replied before Galileo, arguing, like him, that Sunspots must be on the surface of the Sun and not satellites. Kepler reached this conclusion only by studying the evidence Scheiner's had provided, without making any direct observations of his own.
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By comparing the DTO of the reference signal and the DTO of the target signal a result known as Time Difference of Arrival (TDOA) can be calculated. Likewise, from the DFO of the target and the DFO of the reference signal, a Frequency Difference of Arrival (FDOA) can be determined. The TDOA and FDOA results provide a finite number of locations on the Earth’s surface, and therefore, lines of position (LOPs) are determined from the TDOA and FDOA results. A limitation as to how accurately a location can be obtained is knowledge of the satellites' positions and velocities generated by the satellite ephemerides (orbit descriptors).
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Standish's work towards the development of the ephemerides took him also into the field of the history of astronomy, including study of the recently noted occurrence of Neptune in the notes of Galileo, identifying an additional manuscript observation of Neptune by Galileo (who had regarded it as a background star while studying the satellites of Jupiter), and analyzing its significance for the modern-day ephemerides.Standish, E. M. & Nobili, A. M. (1997), Galileo's observations of Neptune, Baltic Astronomy, vol. 6, pp. 97–104. Standish has collaborated with Dr. Elena V. Pitjeva and Dr. Agnes Fienga on the topic of a better determination of the Astronomical Unit and of the masses of the asteroids.
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Jan Franco (active 1586–1611) was a physician, mathematician and astronomer who compiled almanacs. He was born in the village of Eersel in the Duchy of Brabant and studied medicine at the University of Leuven. He settled in Brussels to practice medicine and was given the freedom of the city. He was a practicing physician at least until 1594.Jean-Noël Paquot, Mémoires pour servir à l'histoire littéraire des dix-sept provinces des Pays-Bas, de la principauté de Liège et de quelques contrées voisines (Leuven, Imprimerie académique, 1767), pp. 224–225 As he had studied both medicine and mathematics, he was asked to calculate the ephemerides, for purposes of medical astrology.Aug.
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Jet Propulsion Laboratory Development Ephemeris (abbreved JPL DE(number), or simply DE(number)) designates one of a series of mathematical models of the Solar System produced at the Jet Propulsion Laboratory in Pasadena, California, for use in spacecraft navigation and astronomy. The models consist of numeric representations of positions, velocities and accelerations of major Solar System bodies, tabulated at equally spaced intervals of time, covering a specified span of years. Barycentric rectangular coordinates of the Sun, eight major planets and Pluto, and geocentric coordinates of the Moon are tabulated. DE405, created in May 1997, include both nutations and librations, and is considered the fundamental planetary and lunar ephemerides of The Astronomical Almanac.
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Zacuto developed a new type of astrolabe, specialized for practical determination of latitude while at sea, in contrast to earlier multipurpose devices intended for use ashore. Abraham Zacuto's principal claim to fame is the great astronomical treatise, written while he was in Salamanca, in Hebrew, with the title Ha-ḥibbur ha-gadol ("The Great Book"), begun around 1470 and completed in 1478."Zacuto, Abraham" in Glick, T., S.J. Livesy and F. Williams, editors, (2005) Medieval science, technology, and medicine: an encyclopedia, New York Routledge. It was composed of 65 detailed astronomical tables (ephemerides), with radix set in year 1473 and the meridian at Salamanca, charting the positions of the Sun, Moon and five planets.
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The nocturnal revolutionized long distance seafaring by complementing the use of the astrolabe and ephemerides by now giving sailors an accurate tool with which to discover the time at their position. Both Zacuto and Cortes were respected mathematicians and had determined in their respective publications the trigonometric measurements concerning the degrees of latitude and longitude. If a ship's pilot or navigator used the nocturnal to read their time, and then consulted an astrolabe in concert with astronomical charts they could determine the time distance between themselves and a fixed location. The trigonometry, dictated particularly in Zacuto's work, then allowed a sailor to calculate the degree difference east or west of the fixed position.
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The court of his father was flooded with foreigners enticed by Henry and his appetite for any secrets of navigation they could provide. Although driven by religious motivation forged during the crusades, his influence on Portuguese exploration and patronage of nautical sciences is without doubt. Martin Cortes de Albacar and Abraham Zacuto both published works in the 16th century that became backbones for naval instruction through the end of the 19th century. Cortes's work included detailed instructions on how to both construct and apply an astrolabe while Zacuto's Almanach and the ephemerides published within were critical to the use of a nocturnal, notably by both Vasco da Gama and Pedro Álvares Cabral.
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There were, however, inconclusive observations during the 1865 and 1872 returns. Charles Talmage, using ephemerides provided by John Russell Hind, claimed to have briefly observed a nebulous object in approximately the right position in November 1865. James Buckingham also observed two nebulosities in 1865 after studying Hind's predictions, but Hind subsequently stated that they were unlikely to be Biela's Comet, as they were much closer together than the two components of the comet should have been. A puzzling observation recorded as X/1872 X1, seen by N. R. Pogson in late 1872 from the Madras Observatory, was also speculated to be a recovery of Biela's Comet, though once again this was later shown to have been unlikely.
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ET's direct successor for measuring time on a geocentric basis was Terrestrial Dynamical Time (TDT). The new time scale to supersede ET for planetary ephemerides was to be Barycentric Dynamical Time (TDB). TDB was to tick uniformly in a reference frame comoving with the barycenter of the Solar System. (As with any coordinate time, a corresponding clock, to coincide in rate, would need not only to be at rest in that reference frame, but also (an unattainable hypothetical condition) to be located outside all of the relevant gravity wells.) In addition, TDB was to have (as observed/evaluated at the Earth's surface), over the long term average, the same rate as TDT (now TT).
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Up to a high order of approximation, mutual gravitational perturbations between major or minor planets only cause periodic variations in their orbits, that is, parameters oscillate between maximum and minimum values. The tidal effect gives rise to a quadratic term in the equations, which leads to unbounded growth. In the mathematical theories of the planetary orbits that form the basis of ephemerides, quadratic and higher order secular terms do occur, but these are mostly Taylor expansions of very long time periodic terms. The reason that tidal effects are different is that unlike distant gravitational perturbations, friction is an essential part of tidal acceleration, and leads to permanent loss of energy from the dynamic system in the form of heat.
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A modern-day example of a fully robotic transit telescope is the small Flagstaff Astrometric Scanning Transit Telescope (FASTT) completed in 1981 and located at the observatory. FASTT provides extremely precise positions of solar system objects for incorporation into the USNO Astronomical Almanac and Nautical Almanac. These ephemerides are also used by NASA in the deep space navigation of its planetary and extra- orbital spacecraft. Instrumental to the navigation of many NASA deep space probes, data from this telescope is responsible for NASA JPL's successful 2005 navigation-to-landing of the Huygens Lander on Titan, a major moon orbiting Saturn, and provided navigational reference for NASA's New Horizons deep space mission to Pluto, which arrived in July 2015.
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632 note At least one mathematical astronomer adopted Herschel's "days of the Julian period" immediately. Benjamin Peirce of Harvard University used over 2,800 Julian days in his Tables of the Moon, begun in 1849 but not published until 1853, to calculate the lunar ephemerides in the new American Ephemeris and Nautical Almanac from 1855 to 1888. The days are specified for "Washington mean noon", with Greenwich defined as west of Washington (282°57′W, or Washington 77°3′W of Greenwich). A table with 197 Julian days ("Date in Mean Solar Days", one per century mostly) was included for the years –4713 to 2000 with no year 0, thus "–" means BC, including decimal fractions for hours, minutes and seconds.
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The P-code is a PRN sequence much longer than the C/A code: 6.187104 · 1012 chips (773,388 MByte). Even though the P-code chip rate (10.23 Mchips/s) is ten times that of the C/A code, it repeats only once per week, eliminating range ambiguity. It was assumed that receivers could not directly acquire such a long and fast code so they would first "bootstrap" themselves with the C/A code to acquire the spacecraft ephemerides, produce an approximate time and position fix, and then acquire the P-code to refine the fix. Whereas the C/A PRNs are unique for each satellite, each satellite transmits a different segment of a master P-code sequence approximately 2.35 · 1014 chips long (235,000,000,000,000 bits, ~26.716 terabytes).
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A chapter from an as-yet-unpublished (Feb 2012) version of the Explanatory Supplement (see Sources) The independent variable of the ephemeris is always time. In the case of the most current ephemerides, it is a relativistic coordinate time scale equivalent to the IAU definition of TCB. In the past, mean solar time (before the discovery of the non-uniform rotation of the Earth) and ephemeris time (before the implementation of relativistic gravitational equations) were used. The remainder of the ephemeris can consist of either the mathematical equations and initial conditions which describe the motions of the bodies of the Solar System, of tabulated data calculated from those equations and conditions, or of condensed mathematical representations of the tabulated data.
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In 1759, she was again a part of Lalande's team and worked with him to calculate the ephemeris of the transit of Venus. It is not documented what should be attributed to her personally, but in 1761, she was acknowledged by being inducted as an honorary member of the distinguished Scientific Academy of Béziers. Lalande also collaborated with Lepaute for fifteen years on the Academy of Science's annual guides for astronomers and navigators by developing ephemerides: tables that predict the location of the stars on each day of the year, and after her death, wrote a brief biography about her contributions to astronomy. In 1762, Lepaute calculated the exact time of a solar eclipse that occurred on 1 April 1764.
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On January 1, 2005 the combined Center for Astronomy institute formed by combining ARI, with the Institute of Theoretical Astrophysics (', ITA) and the Landessternwarte Heidelberg-Königstuhl ("Heidelberg-Königstuhl State Observatory", LSW). The ARI has been responsible among other things for the Gliese catalog of nearby stars, the fundamental catalogs FK5 and FK6, and the annually-published "Apparent Places of Fundamental Stars" (APFS),Apparent Places of Fundamental Stars stellar ephemerides that provide high-precision mean and apparent positions of over three thousand stars for each day. During 1938–1945, whilst based in Berlin, ARI published the academic journal Astronomical Notes (). , ARI was not limited to only publishing star catalogs, but has a wider research scope, including gravitational lensing, galaxy evolution, stellar dynamics, and cosmology.
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Media analyst Claudia Chiorean sees Ivașcu as one of Ceaușescu's "first violinists", whose bad reputation also harmed Manolescu's own.Claudia Talașman Chiorean, "Promovarea mitului Erei Noi în perioada 1989-2000 prin România Literară", in Studia Universitas Babeș-Bolyai Ephemerides, LII:1, 2007, p.139 By then, Ivașcu was making occasional returns to agitprop in the film industry supervisor, this time as a promoter of Ceaușescu's national communism. Anca Alexandrescu, "Filmul românesc și educația în procesul de formare al omului nou", in Sfera Politicii, Nr. 135, May 2009 Ivașcu still made a point of promoting foreign literature and the more daring aspects of Romanian modernism, putting out poetry by Blandiana, Mircea Dinescu, and Ion Caraion, as well as essays by Iorgulescu and Sami Damian.
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De Sitter offered a correction to be applied to the mean solar time given by the Earth's rotation to get uniform time. Other astronomers of the period also made suggestions for obtaining uniform time, including A Danjon (1929), who suggested in effect that observed positions of the Moon, Sun and planets, when compared with their well-established gravitational ephemerides, could better and more uniformly define and determine time.G M Clemence (1971). Thus the aim developed, to provide a new time scale for astronomical and scientific purposes, to avoid the unpredictable irregularities of the mean solar time scale, and to replace for these purposes Universal Time (UT) and any other time scale based on the rotation of the Earth around its axis, such as sidereal time.
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Partly in acknowledgement of the widespread use of Teph via the JPL ephemerides, IAU resolution 3 of 2006IAU 2006 resolution 3 (re-)defined Barycentric Dynamical Time (TDB) as a current standard. As re-defined in 2006, TDB is a linear transformation of TCB. The same IAU resolution also stated (in note 4) that the "independent time argument of the JPL ephemeris DE405, which is called Teph" (here the IAU source cites), "is for practical purposes the same as TDB defined in this Resolution". Thus the new TDB, like Teph, is essentially a more refined continuation of the older ephemeris time ET and (apart from the periodic fluctuations) has the same mean rate as that established for ET in the 1950s.
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But ET in principle did not yet take account of relativity theory. The size of the periodic part of the variations due to time dilation between earth-based atomic clocks and the coordinate time of the Solar-System barycentric reference frame had been estimated at under 2 milliseconds, but in spite of this small size, it was increasingly considered in the early 1970s that time standards should be made suitable for applications in which differences due to relativistic time dilation could no longer be neglected. In 1976, two new time scales were definedThey were defined in substance in 1976 but given their names in 1979. to replace ET (in the ephemerides for 1984 and afterwards) to take account of relativity.
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"God God, who had believed that we will find brothers from the same ancient father in the Lapp people! Hungarians, our brethren, who speak our Hungarian language, wear our Hungarian clothes, live according to the customs of our Hungarian fathers, summing it up: our brethren." Maximilian Hell's letter to Pater Höller, written in Vardø, April 6, 1769. More letters from Hell at: (Hungarian) Hell with another Jesuit priest, János Sajnovics tried to explore the already widely discussed but insufficiently documented affinity between the language of the Sami, Finns and the Hungarians during and after their residency in Vardø. (Demonstratio idioma Ungarorum et Lapponum idem esse, 1770 Copenhagen) Title page of the Ephemerides Vindobonensem for 1781 Hell became the director of the Vienna Observatory in 1756.
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ELP gives a series expansion of the orbital elements and the coordinates of the Moon. The authors refer to it as a "semi-analytical" theory because they developed their expressions not purely symbolically, but introduced numerical values for orbital constants from the outset; but they also constructed partial derivatives of all terms with respect to these constants, so they could make corrections afterwards to reach the final solution. ELP has been fitted not directly to observations, but to the numerical integrations known as the Jet Propulsion Laboratory Development Ephemeris (which includes the Lunar Ephemerides), that in their turn have been fitted to actual astronomical observations. ELP was fitted initially to the DE200, but improved parameters have been published up to DE405.
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There are those who claim to be the key to all their attitudes in the phrase - "Why should we question what is best to do, if the tightness of our current circumstances only allows us to ask what can be done?" José Pedro Xavier da Veiga, in Ephemerides Mineiras, says: "Practical and positive spirit until insensitivity, he recommended to social problems solutions according to the tangible interest of the State, although high principles of a moral order perished." Therefore, the coming of slaves Negroes to Brazil seemed to him an imperious necessity of civilization and the development of the country. In 1826, D. João VI died, and the emperor was summoned to Portugal, absorbed by the complications of the Portuguese politics.
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Brown's Tables were adopted by nearly all of the national ephemerides in 1923 for their calculations of the Moon's position, and continued to be used with some modification until 1983. With the advent of digital computers, Brown's original trigonometrical expressions, given in the introduction to his 1919 tables (and from which the tables had been compiled), began to be used for direct computation instead of the tables themselves. This also gained some improvement in precision, since the tables had embodied some minor approximations, in a trade-off between accuracy and the amount of labour needed for computations in those days of manual calculation. By the middle of the 20th century, the difference between Universal and Ephemeris Time had been recognised and evaluated, and the troublesome empirical terms were removed.
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The squadron initially made orbital predictions by computing ephemerides based on standard Kepler orbits. As a satellite got lower into the atmosphere, drag made it difficult to forecast the ephemeris of the satellite accurately.Cotter, Lawrence R.. Reminiscences About Space Track History. Privately published. Berkeley CA, 20 November 2006. By 1962, the situation was somewhat better. The Soviet satellite Sputnik 4 was slowly entering lower orbits because of atmospheric drag. Using a new program, (Satellite General Perturbations Differential Corrections) and observations from the radar at Shemya Air Force Station, the orbital analyst plotted the changing orbital period and was able to predict the exact revolution on which the satellite reentered the atmosphere.A 20-pound piece of it landed on a street in downtown Manitowoc, Wisconsin on the western shore of Lake Michigan.
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Idem and other inspired classics; as well as of the Fellowship's own splendid orchestra composed of permanent students, that it would perform in the theatre works of master composers, particularly those of Beethoven and Wagner whom he knew to be high musical Initiates, and also that classes in initiatory music would be taught there. The Fellowship runs its own printing press, established by Max Heindel in 1912, which is an area of great activity with hundreds of products being produced: printing the ephemerides, the books (with millions spread worldwide),Description of Books. Idem most of the course materials sent to the members,Study Rosicrucian Fundamentals at Home. Idem the periodical Echoes from Mount Ecclesia (which became the Rays from The Rosy Cross in July 1915),Echoes from Mount Ecclesia, Iapsop.
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Schöner was born on 16 January 1477 in Karlstadt am Main in Lower Franconia. As with most Renaissance scholars nothing is known about his parents or his early life. All that is known is that he had a brother, Peter, to whom he addressed his "Arzneibuch" in 1528. Quite detailed information for Schöner’s adult life, at least up to 1506, has been preserved in his own marginalia in his copy of Regiomontanus' printed Ephemerides, which he used as a diary. He matriculated at the University of Erfurt in the winter semester 1494/5 and graduated Baccalaureus on 21 March 1498. He was appointed to a position in the school in Gemünden on 22 February 1499 and ordained as a Catholic priest in the Bishopric of Bamberg on 13 June 1500.
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Pierre-Jean Grosley Observations sur l'Italie et sur les Italiens (1774) Pierre-Jean Grosley (Troyes, 18 November 1718 – Troyes, 4 November 1785) was a French man of letters, local historian, travel writer and observer of social mores in the Age of Enlightenment and a contributor to the Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers. Frank A. Kafker: Notices sur les auteurs des dix-sept volumes de « discours » de l'Encyclopédie. Recherches sur Diderot et sur l'Encyclopédie. 1989, Volume 7, Numéro 7, p. 142–144 Grosley was a magistrate in his native Troyes, where he had plenty of opportunity to hear the local dialect, which he described in a paper (1761).Grosley, "Vocabulaire troyen ou le parler de la region de Troyes", Ephemerides 1761; a reprint was issued (Saint-Julien: Édition de Sancey) 1984 ISBN B000OW1SG4 .
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A primitive form of harmonic series dates back to ancient Babylonian mathematics, where they were used to compute ephemerides (tables of astronomical positions). The classical Greek concepts of deferent and epicycle in the Ptolemaic system of astronomy were related to Fourier series (see ). In modern times, variants of the discrete Fourier transform were used by Alexis Clairaut in 1754 to compute an orbit, which has been described as the first formula for the DFT, and in 1759 by Joseph Louis Lagrange, in computing the coefficients of a trigonometric series for a vibrating string. Technically, Clairaut's work was a cosine-only series (a form of discrete cosine transform), while Lagrange's work was a sine-only series (a form of discrete sine transform); a true cosine+sine DFT was used by Gauss in 1805 for trigonometric interpolation of asteroid orbits.
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Classical Greek and Latin sources frequently use the term Chaldeans for the astronomers of Mesopotamia, who were considered as priest-scribes specializing in astrology and other forms of divination. Only fragments of Babylonian astronomy have survived, consisting largely of contemporary clay tablets containing astronomical diaries, ephemerides and procedure texts, hence current knowledge of Babylonian planetary theory is in a fragmentary state. Nevertheless, the surviving fragments show that Babylonian astronomy was the first "successful attempt at giving a refined mathematical description of astronomical phenomena" and that "all subsequent varieties of scientific astronomy, in the Hellenistic world, in India, in Islam, and in the West … depend upon Babylonian astronomy in decisive and fundamental ways." The origins of Western astronomy can be found in Mesopotamia, and all Western efforts in the exact sciences are descendants in direct line from the work of the late Babylonian astronomers.
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Swedish astronomer Pehr Wilhelm Wargentin (1717–83) used Rømer's method in the preparation of his ephemerides of Jupiter's moons (1746), as did Giovanni Domenico Maraldi working in Paris. The remaining irregularities in the orbits of the Galilean moons would not be satisfactorily explained until the work of Joseph Louis Lagrange (1736–1813) and Pierre-Simon Laplace (1749–1827) on orbital resonance. In 1809, again making use of observations of Io, but this time with the benefit of more than a century of increasingly precise observations, the astronomer Jean Baptiste Joseph Delambre (1749–1822) reported the time for light to travel from the Sun to the Earth as 8 minutes 12 seconds. Depending on the value assumed for the astronomical unit, this yields the speed of light as just a little more than 300,000 kilometres per second.
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See G M Clemence's proposal of 1948, contained in his paper: "On the System of Astronomical Constants", Astronomical Journal (1948) vol.53 (6), issue #1170, pp 169–179; also G M Clemence (1971), "The Concept of Ephemeris Time", in Journal for the History of Astronomy v2 (1971), pp. 73–79 (giving details of the genesis and adoption of the ephemeris time proposal); also article Ephemeris time and references therein. Newcomb's tables formed the basis of all astronomical ephemerides of the Sun from 1900 through 1983: they were originally expressed (and published) in terms of Greenwich Mean Time and the mean solar day,Newcomb's Tables of the Sun (Washington, 1895), Introduction, I. Basis of the Tables, pp. 9 and 20, citing time units of Greenwich Mean Noon, Greenwich Mean Time, and mean solar dayW de Sitter, on p.
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He then taught at the Alberoni and at San Jacopo in Florence. He returned to the military from 1915 to 1919 as a chaplain during World War I. After the war he returned to teaching and began his fifteen years in charge of the order’s principal publication, the Annals of the Missions, moving its operations to Rome where he headed the Pontifical Liturgical Academy and as editor transformed Ephemerides Liturgicae, an international journal associated with the Congregation for Rites. From 1921 to 1932 he headed Collegio Alberoni as well. There he initiated a revival of studies devoted to Thomas Aquinas and the translation into Italian of the work of Vincent de Paul, as well as the expansion of its science program and art gallery. As Visitor of the Missions he led the Roman province of the order from 1932 to 1936.
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A spherical triangle In sixteenth century Europe, celestial navigation of ships on long voyages relied heavily on ephemerides to determine their position and course. These voluminous charts prepared by astronomers detailed the position of stars and planets at various points in time. The models used to compute these were based on spherical trigonometry, which relates the angles and arc lengths of spherical triangles (see diagram, right) using formulas such as: :\cos a = \cos b \cos c + \sin b \sin c \cos \alpha and :\sin b \sin \alpha = \sin a \sin \beta where a, b and c are the angles subtended at the centre of the sphere by the corresponding arcs. When one quantity in such a formula is unknown but the others are known, the unknown quantity can be computed using a series of multiplications, divisions, and trigonometric table lookups.
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Using Ole Rømer's data and a modern value for the astronomical unit, his measurement that light takes 16.44 minutes to travel the distance of the diameter of Earth's orbit was only 2% greater than the modern-day value, though this was not calculated at the time. In 1809, again making use of observations of Io, but this time with the benefit of more than a century of increasingly precise observations, the French astronomer Jean Baptiste Joseph Delambre reported the time for light to travel from the Sun to the Earth as 8 minutes and 12 seconds. Depending on the value assumed for the astronomical unit, this yields the speed of light as just a little more than per second. In 1788, Pierre-Simon Laplace used Cassini's ephemerides and those produced by other astronomers in the preceding century to create a mathematical theory explaining the resonant orbits of Io, Europa, and Ganymede.
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De Sitter and Clemence both referred to the proposal as 'Newtonian' or 'uniform' time. D Brouwer suggested the name 'ephemeris time'.ESAA (1992), see page 79. Following this, an astronomical conference held in Paris in 1950 recommended "that in all cases where the mean solar second is unsatisfactory as a unit of time by reason of its variability, the unit adopted should be the sidereal year at 1900.0, that the time reckoned in this unit be designated ephemeris time", and gave Clemence's formula (see Definition of ephemeris time (1952)) for translating mean solar time to ephemeris time. The International Astronomical Union approved this recommendation at its 1952 general assembly.At the IAU meeting in Rome 1952: see ESAE (1961) at sect.1C, p. 9; also Clemence (1971). Practical introduction took some time (see Use of ephemeris time in official almanacs and ephemerides); ephemeris time (ET) remained a standard until superseded in the 1970s by further time scales (see Revision).
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TDB is a successor of Ephemeris Time (ET), in that ET can be seen (within the limits of the lesser accuracy and precision achievable in its time) to be an approximation to TDB as well as to Terrestrial Time (TT) (see Ephemeris time § Implementations). TDB in the form of the very closely analogous, and practically equivalent, time scale Teph continues to be used for the important DE405 planetary and lunar ephemerides from the Jet Propulsion Laboratory. Arguments have been put forward for the continued practical use of TDB rather than TCB based on the very small size of the difference between TDB and TT, not exceeding 0.002 second, which can be neglected for many applications. It has been argued that the smallness of this difference makes for a lower risk of damage if TDB is ever confused with TT, compared to the possible damage of confusing TCB and TT, which have a relative linear drift of about 0.5 second per year,S A Klioner (2008), "Relativistic scaling of astronomical quantities and the system of astronomical units", Astronomy and Astrophysics, vol.
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Consequently, most modern scholars consider his text to be of dubious quality.Bruce Metzger The Text of the New Testament, p. 99 With the third edition of Erasmus' Greek text (1522) the Comma Johanneum was included because "Erasmus chose to avoid any occasion for slander rather than persisting in philological accuracy" even though he remained "convinced that it did not belong to the original text of l John."H. J. de Jonge, Erasmus and the Comma Johanneum, Ephemerides Theologicae Lovanienses (1980), p. 385 Popular demand for Greek New Testaments led to a flurry of further authorized and unauthorized editions in the early sixteenth century, almost all of which were based on Erasmus' work and incorporated his particular readings but typically also making a number of minor changes of their own.S. P. Tregelles, An Account of the Printed Text of the Greek New Testament, London 1854, p. 29. 4th edition of New Testament of Robert Estienne The overwhelming success of Erasmus' Greek New Testament completely overshadowed the Latin text upon which he had focused. Many other publishers produced their own versions of the Greek New Testament over the next several centuries.
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Bode was born in Hamburg. As a youth, he suffered from a serious eye disease which particularly damaged his right eye; he continued to have trouble with his eyes throughout his life. His early promise in mathematics brought him to the attention of Johann Georg Büsch, who allowed Bode to use his own library for study. He began his career with the publication of a short work on the solar eclipse of 5 August 1766. This was followed by an elementary treatise on astronomy entitled Anleitung zur Kenntniss des gestirnten Himmels (1768, 10th ed. 1844), the success of which led to his being invited to Berlin by Johann Heinrich Lambert in 1772 for the purpose of computing ephemerides on an improved plan. There he founded, in 1774, the well-known Astronomisches Jahrbuch, 51 yearly volumes of which he compiled and issued. He became director of the Berlin Observatory in 1786, from which he retired in 1825. There he published the Uranographia in 1801, a celestial atlas that aimed both at scientific accuracy in showing the positions of stars and other astronomical objects, as well as the artistic interpretation of the stellar constellation figures.
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Leopold I of the Holy Roman Empire Miscellanea Curiosa (1692) An illustration of the Acta Eruditorum of 1712 where the Naturae Curiosorum Ephemerides were published The Leopoldina was founded in the imperial city of Schweinfurt on 1 January 1652 under the Latin name sometimes translated into English as "Academy of the Curious as to Nature."As for instance in the monumental A History of Magic and Experimental Science by Lynn Thorndike (see online). It was founded by four local physicians- Johann Laurentius Bausch, the first president of the society, Johann Michael Fehr, Georg Balthasar Metzger, and Georg Balthasar Wohlfarth; and was the only academy like it at the time making it the oldest academy of science in Germany. The archives of Leopoldina are some of the oldest in the world based on the fact that the records date back to the 17th century. These records will provide a window into the German sciences of the last 350 years. In 1670 the society began to publish the Ephemeriden or Miscellanea Curiosa, one of the earliest scientific journals and one which had a particularly strong focus on medicine and related aspects of natural philosophy, such as botany and physiology.
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Barycentric Dynamical Time (TDB, from the French Temps Dynamique Barycentrique) is a relativistic coordinate time scale, intended for astronomical use as a time standard to take account of time dilationExplanations given with (a) IAU resolutions 1991, under Resolution A.4, at 'Notes for recommendation III', and IAU 2006 resolution 3, and its footnotes; and (b) explanations and references cited at "Time dilation -- due to gravitation and motion together". when calculating orbits and astronomical ephemerides of planets, asteroids, comets and interplanetary spacecraft in the Solar System. TDB is now (since 2006) defined as a linear scaling of Barycentric Coordinate Time (TCB). A feature that distinguishes TDB from TCB is that TDB, when observed from the Earth's surface, has a difference from Terrestrial Time (TT) that is about as small as can be practically arranged with consistent definition: the differences are mainly periodic,The periodic differences, due to relativistic effects, between a coordinate time scale applicable to the Solar-System barycenter, and time measured at the Earth's surface, were first estimated and are explained in: G M Clemence & V Szebehely, "Annual variation of an atomic clock", Astronomical Journal, Vol.
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