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Saros Cycle
The saros () is a period of exactly 223 synodic months, approximately 6585.3211 days, or 18 years, 10, 11, or 12 days (depending on the number of leap years), and 8 hours, that can be used to predict eclipses of the Sun and Moon. One saros period after an eclipse, the Sun, Earth, and Moon return to approximately the same relative geometry, a near straight line, and a nearly identical eclipse will occur, in what is referred to as an eclipse cycle. A sar is one half of a saros. A series of eclipses that are separated by one saros is called a ''saros series''. It corresponds to: *6,585.321347 solar days *18.029 years *223 synodic months *241.999 draconic months *18.999 eclipse years (38 eclipse seasons) *238.992 anomalistic months The 19 eclipse years means that if there is a solar eclipse (or lunar eclipse), then after one saros a new moon will take place at the same node of the orbit of the Moon, and under these circumstances another eclipse can occur. History The earliest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synodic Month
In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and European traditions, the month starts when the young crescent moon first becomes visible, at evening, after conjunction with the Sun one or two days before that evening (e.g., in the Islamic calendar). In ancient Egypt, the lunar month began on the day when the waning moon could no longer be seen just before sunrise. Others run from full moon to full moon. Yet others use calculation, of varying degrees of sophistication, for example, the Hebrew calendar or the ecclesiastical lunar calendar. Calendars count integer days, so months may be 29 or 30 days in length, in some regular or irregular sequence. Lunar cycles are prominent, and calculated with great precision, in the ancient Hindu Panchangam calendar, widely used in the Indian subco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliny The Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic '' Naturalis Historia'' (''Natural History''), which became an editorial model for encyclopedias. He spent most of his spare time studying, writing, and investigating natural and geographic phenomena in the field. His nephew, Pliny the Younger, wrote of him in a letter to the historian Tacitus: Among Pliny's greatest works was the twenty-volume work ''Bella Germaniae'' ("The History of the German Wars"), which is no longer extant. ''Bella Germaniae'', which began where Aufidius Bassus' ''Libri Belli Germanici'' ("The War with the Germans") left off, was used as a source by other prominent Roman historians, including Plutarch, Tacitus and Suetonius. Tacitus—who many scholars agree had never travelled in Germania—used ''Bella Ger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antikythera Mechanism
The Antikythera mechanism ( ) is an Ancient Greek hand-powered orrery, described as the oldest example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games. This artefact was among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera in 1901. On 17 May 1902, it was identified as containing a gear by archaeologist Valerios Stais. The device, housed in the remains of a wooden-framed case of (uncertain) overall size , was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is approximately in diameter and originally had 223 teeth. In 2008, a team led by Mike Edmunds and Tony Freet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Numerals
Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, are a system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal numbers and in contexts similar to those in which Roman numerals are still used in the Western world. For ordinary cardinal numbers, however, modern Greece uses Arabic numerals. History The Minoan and Mycenaean civilization Mycenaean Greece (or the Mycenaean civilization) was the last phase of the Bronze Age in Ancient Greece, spanning the period from approximately 1750 to 1050 BC.. It represents the first advanced and distinctively Greek civilization in mainland ...s' Linear A and Linear B alphabets used a different system, called Aegean numerals, which included number-only symbols for powers of ten: = 1, = 10, = 100, = 1000, and = 10000. Attic numerals comprised another system that came into use perhaps in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manual2021-X MOUSSAS SAROS
Manual may refer to: Instructions * User guide * Owner's manual * Instruction manual (gaming) * Online help Other uses * Manual (music), a keyboard, as for an organ * Manual (band) * Manual transmission A manual transmission (MT), also known as manual gearbox, standard transmission (in Canada, the United Kingdom, and the United States), or stick shift (in the United States), is a multi-speed motor vehicle transmission (mechanics), transmission ... * Manual, a bicycle technique similar to a wheelie, but without the use of pedal torque * Manual, balancing on two wheels in freestyle skateboarding tricks * '' The Manual (How to Have a Number One the Easy Way)'' is a 1988 book by Bill Drummond and Jimmy Cauty See also * Instructions (other) * Tutorial {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guillaume Le Gentil
Guillaume Joseph Hyacinthe Jean-Baptiste Le Gentil de la Galaisière (, 12 September 1725 – 22 October 1792) was a French astronomer who discovered several nebulae and was appointed to the Royal Academy of Sciences. He made unsuccessful attempts to observe the 1761 and 1769 transits of Venus from India. Biography Guillaume Le Gentil was born in Coutances and first intended to enter the church before turning to astronomy. He discovered what are now known as the Messier objects M32, M36 and M38, as well as the nebulosity in M8, and he was the first to catalogue the dark nebula sometimes known as Le Gentil 3 (in the constellation Cygnus). He was part of the international collaborative project organized by Mikhail Lomonosov to measure the distance to the Sun, by observing the transit of Venus at different points on the earth. Edmond Halley had suggested the idea, but it required careful measurements from different places on earth, and the project was launched with more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berossus
Berossus () or Berosus (; grc, Βηρωσσος, Bērōssos; possibly derived from akk, , romanized: , "Bel is his shepherd") was a Hellenistic-era Babylonian writer, a priest of Bel Marduk and astronomer who wrote in the Koine Greek language, and who was active at the beginning of the 3rd century BC. Versions of two excerpts of his writings survive, at several removes from the original. Life and work Using ancient Babylonian records and texts that are now lost, Berossus published the ''Babyloniaca'' (hereafter, ''History of Babylonia'') in three books some time around 290–278 BC, by the patronage of the Macedonian/ Seleucid king Antiochus I Soter (during the third year of his reign, according to Diodorus Siculus). Certain astrological fragments recorded by Pliny the Elder, Censorinus, Flavius Josephus, and Marcus Vitruvius Pollio are also attributed to Berossus, but are of unknown provenance, or indeed are uncertain as to where they might fit into his ''History''. Vitru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eusebius Of Caesarea
Eusebius of Caesarea (; grc-gre, Εὐσέβιος ; 260/265 – 30 May 339), also known as Eusebius Pamphilus (from the grc-gre, Εὐσέβιος τοῦ Παμφίλου), was a Greek historian of Christianity, exegete, and Christian polemicist. In about AD 314 he became the bishop of Caesarea Maritima in the Roman province of Syria Palaestina. Together with Pamphilus, he was a scholar of the biblical canon and is regarded as one of the most learned Christians during late antiquity. He wrote ''Demonstrations of the Gospel'', '' Preparations for the Gospel'' and ''On Discrepancies between the Gospels'', studies of the biblical text. As "Father of Church History" (not to be confused with the title of Church Father), he produced the '' Ecclesiastical History'', ''On the Life of Pamphilus'', the ''Chronicle'' and ''On the Martyrs''. He also produced a biographical work on Constantine the Great, the first Christian Roman emperor, who was ''augustus'' between AD 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaldea
Chaldea () was a small country that existed between the late 10th or early 9th and mid-6th centuries BCE, after which the country and its people were absorbed and assimilated into the indigenous population of Babylonia. Semitic-speaking, it was located in the marshy land of the far southeastern corner of Mesopotamia and briefly came to rule Babylon. The Hebrew Bible uses the term (''Kaśdim'') and this is translated as ''Chaldaeans'' in the Greek Old Testament, although there is some dispute as to whether ''Kasdim'' in fact means ''Chaldean'' or refers to the south Mesopotamian ''Kaldu''. During a period of weakness in the East Semitic-speaking kingdom of Babylonia, new tribes of West Semitic-speaking migrants arrived in the region from the Levant between the 11th and 9th centuries BCE. The earliest waves consisted of Suteans and Arameans, followed a century or so later by the Kaldu, a group who became known later as the Chaldeans or the Chaldees. These migrations did not aff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byzantine
The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinople. It survived the fragmentation and fall of the Western Roman Empire in the 5th century AD and continued to exist for an additional thousand years until the fall of Constantinople to the Ottoman Empire in 1453. During most of its existence, the empire remained the most powerful economic, cultural, and military force in Europe. The terms "Byzantine Empire" and "Eastern Roman Empire" were coined after the end of the realm; its citizens continued to refer to their empire as the Roman Empire, and to themselves as Romans—a term which Greeks continued to use for themselves into Ottoman times. Although the Roman state continued and its traditions were maintained, modern historians prefer to differentiate the Byzantine Empire from Ancient Rome a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suda
The ''Suda'' or ''Souda'' (; grc-x-medieval, Σοῦδα, Soûda; la, Suidae Lexicon) is a large 10th-century Byzantine encyclopedia of the ancient Mediterranean world, formerly attributed to an author called Soudas (Σούδας) or Souidas (Σουίδας). It is an encyclopedic lexicon, written in Greek, with 30,000 entries, many drawing from ancient sources that have since been lost, and often derived from medieval Christian compilers. Title The derivation is probably from the Byzantine Greek word '' souda'', meaning "fortress" or "stronghold", with the alternate name, ''Suidas'', stemming from an error made by Eustathius, who mistook the title for the author's name. Paul Maas once ironized by suggesting that the title may be connected to the Latin verb ''suda'', the second-person singular imperative of ''sudāre'', meaning "to sweat", but Franz Dölger traced its origins back to Byzantine military lexicon (σοῦδα, "ditch, trench", then "fortress"). Silvio G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edmond Halley
Edmond (or Edmund) Halley (; – ) was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720. From an observatory he constructed on Saint Helena in 1676–77, Halley catalogued the southern celestial hemisphere and recorded a transit of Mercury across the Sun. He realised that a similar transit of Venus could be used to determine the distances between Earth, Venus, and the Sun. Upon his return to England, he was made a fellow of the Royal Society, and with the help of King Charles II, was granted a master's degree from Oxford. Halley encouraged and helped fund the publication of Isaac Newton's influential ''Philosophiæ Naturalis Principia Mathematica'' (1687). From observations Halley made in September 1682, he used Newton's laws of motion to compute the periodicity of Halley's Comet in his 1705 ''Synopsis of the Astronomy of Comets''. It was named after him upon its predicted return in 1758, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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