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Meton Of Athens
Meton of Athens (; ''gen''.: Μέτωνος) was a Greek mathematician, astronomer, geometer, and engineer who lived in Athens in the 5th century BC. He is best known for calculations involving the eponymous 19-year Metonic cycle, which he introduced in 432 BC into the lunisolar Attic calendar. Euphronios says that Colonus was Meton's deme. Work The Metonic calendar incorporates knowledge that 19 solar years and 235 lunar months are very nearly of the same duration. Consequently, a given day of a lunar month will often occur on the same day of the solar year as it did 19 years previously. Meton's observations were made in collaboration with Euctemon, about whom nothing else is known. The Greek astronomer Callippus expanded on the work of Meton, proposing what is now called the Callippic cycle. A Callippic cycle runs for 76 years, or four Metonic cycles. Callippus refined the lunisolar calendar, deducting one day from the fourth Metonic cycle in each Callippic cycle (i. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brackets
A bracket is either of two tall fore- or back-facing punctuation marks commonly used to isolate a segment of text or data from its surroundings. They come in four main pairs of shapes, as given in the box to the right, which also gives their names, that vary between British English, British and American English. "Brackets", without further qualification, are in British English the ... marks and in American English the ... marks. Other symbols are repurposed as brackets in specialist contexts, such as International Phonetic Alphabet#Brackets and transcription delimiters, those used by linguists. Brackets are typically deployed in symmetric pairs, and an individual bracket may be identified as a "left" or "right" bracket or, alternatively, an "opening bracket" or "closing bracket", respectively, depending on the Writing system#Directionality, directionality of the context. In casual writing and in technical fields such as computing or linguistic analysis of grammar, brackets ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar 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, the Chinese 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 us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stele
A stele ( ) or stela ( )The plural in English is sometimes stelai ( ) based on direct transliteration of the Greek, sometimes stelae or stelæ ( ) based on the inflection of Greek nouns in Latin, and sometimes anglicized to steles ( ) or stelas ( ). is a stone or wooden slab, generally taller than it is wide, erected in the ancient world as a monument. The surface of the stele often has text, ornamentation, or both. These may be inscribed, carved in relief, or painted. Stelae were created for many reasons. Grave stelae were used for funerary or commemorative purposes. Stelae as slabs of stone would also be used as ancient Greek and Roman government notices or as boundary markers to mark borders or property lines. Stelae were occasionally erected as memorials to battles. For example, along with other memorials, there are more than half-a-dozen steles erected on the battlefield of Waterloo at the locations of notable actions by participants in battle. A traditional Wester ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ptolemy
Claudius Ptolemy (; , ; ; – 160s/170s AD) was a Greco-Roman mathematician, astronomer, astrologer, geographer, and music theorist who wrote about a dozen scientific treatises, three of which were important to later Byzantine science, Byzantine, Islamic science, Islamic, and Science in the Renaissance, Western European science. The first was his astronomical treatise now known as the ''Almagest'', originally entitled ' (, ', ). The second is the ''Geography (Ptolemy), Geography'', which is a thorough discussion on maps and the geographic knowledge of the Greco-Roman world. The third is the astrological treatise in which he attempted to adapt horoscopic astrology to the Aristotelian physics, Aristotelian natural philosophy of his day. This is sometimes known as the ' (, 'On the Effects') but more commonly known as the ' (from the Koine Greek meaning 'four books'; ). The Catholic Church promoted his work, which included the only mathematically sound geocentric model of the Sola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surveying
Surveying or land surveying is the technique, profession, art, and science of determining the land, terrestrial Plane (mathematics), two-dimensional or Three-dimensional space#In Euclidean geometry, three-dimensional positions of Point (geometry), points and the Euclidean distance, distances and angles between them. These points are usually on the surface of the Earth, and they are often used to establish maps and boundaries for ownership, locations, such as the designated positions of structural components for construction or the surface location of subsurface features, or other purposes required by government or civil law, such as property sales. A professional in land surveying is called a land surveyor. Surveyors work with elements of geodesy, geometry, trigonometry, regression analysis, physics, engineering, metrology, programming languages, and the law. They use equipment, such as total stations, robotic total stations, theodolites, Satellite navigation, GNSS receivers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Birds (play)
''The Birds'' () is a comedy by the Ancient Greek playwright Aristophanes. It was performed in 414 BC at the City Dionysia in Athens where it won second place. It has been acclaimed by modern critics as a perfectly realized fantasy remarkable for its mimicry of birds and for the gaiety of its songs. Unlike the author's other early plays, it includes no direct mention of the Peloponnesian War and there are few references to Athenian politics, and yet it was staged not long after the commencement of the Sicilian Expedition, an ambitious military campaign that greatly increased Athenian commitment to the war effort. In spite of that, the play has many indirect references to Athenian political and social life. It is the longest of Aristophanes's surviving plays and yet it is a fairly conventional example of Old Comedy. The plot of the play revolves around Pisthetaerus, an Athenian who convinces the birds to create a great city in the sky, and thus regain their status as the original ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristophanes
Aristophanes (; ; ) was an Ancient Greece, Ancient Greek Ancient Greek comedy, comic playwright from Classical Athens, Athens. He wrote in total forty plays, of which eleven survive virtually complete today. The majority of his surviving plays belong to the genre of comic drama known as Old Comedy and are considered its most valuable examples. Aristophanes' plays were performed at the religious festivals of Athens, mostly the City Dionysia and the Lenaia, and several of them won the first prize in their respective competitions. Also known as "The Father of Comedy" and "the Prince of Ancient Comedy", Aristophanes wrote plays that often dealt with real-life figures, including Euripides and Alcibiades, and contemporary events, such as the Peloponnesian War. He has been said to recreate the life of ancient Athens more convincingly than any other author. His plays are characterized by preposterous premises, explicit language, wordplays, and political satire. His powers of ridicule ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winter Solstice
The winter solstice, or hibernal solstice, occurs when either of Earth's geographical pole, poles reaches its maximum axial tilt, tilt away from the Sun. This happens twice yearly, once in each hemisphere (Northern Hemisphere, Northern and Southern Hemisphere, Southern). For that hemisphere, the winter solstice is the day with the shortest daytime, period of daylight and longest night of the year, and when the Sun is at its lowest culmination, daily maximum elevation in the sky. Each Polar Circle, polar region experiences polar night, continuous darkness or twilight around its winter solstice. The opposite event is the summer solstice. The winter solstice occurs during the hemisphere's winter. In the Northern Hemisphere, this is the December solstice (December 21 or 22) and in the Southern Hemisphere, this is the June solstice (June 20 or 21). Although the winter solstice itself lasts only a moment, the term also refers to the day on which it occurs. Traditionally, in many Tem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Summer Solstice
The summer solstice or estival solstice occurs when one of Earth's poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere ( Northern and Southern). The summer solstice is the day with the longest period of daylight and shortest night of the year in that hemisphere, when the sun is at its highest position in the sky. At either pole there is continuous daylight at the time of its summer solstice. The opposite event is the winter solstice. The summer solstice occurs during the hemisphere's summer. In the Northern Hemisphere, this is the June solstice (20, 21 or 22 June) and in the Southern Hemisphere, this is the December solstice (20, 21, 22 or 23 of December). Since prehistory, the summer solstice has been a significant time of year in many cultures, and has been marked by festivals and rituals. Traditionally, in temperate regions (especially Europe), the summer solstice is seen as the middle of summer and referred to as midsum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pnyx
The Pnyx (; ; , ''Pnyka'') is a hill or hillside in central Athens, the capital of Greece. Beginning as early as 507 BC (Fifth-century Athens), the Athenians gathered on the Pnyx to host their popular assemblies, thus making the hill one of the earliest and most important sites in the creation of democracy. The Pnyx is located less than west of the Acropolis and about 2 km south-west of the Syntagma Square in the centre of Athens. The "mainly natural hollow" was first used from before 500 BC to perhaps 404 BC, when the arrangement was changed by adding a retaining wall below the speakers' platform, with the space between filled with earth. The Pnyx was probably the prototype for the Greek theatre auditorium, with the late form perhaps reflecting changes in theatre design. Historical significance The Pnyx was used for popular assemblies in Athens as early as 507 BC, when the reforms of Cleisthenes transferred political power to the citizenry. It was then outside the city prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antikythera Mechanism
The Antikythera mechanism ( , ) is an Ancient Greece, Ancient Greek hand-powered orrery (model of the Solar System). It is the oldest known example of an Analog computer, analogue computer. It could be used to predict astronomy, astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games similar to an Olympiad, the cycle of the ancient Olympic Games. The artefact was among wreckage retrieved from Antikythera wreck, a shipwreck off the coast of the Greek island Antikythera in 1901. In 1902, during a visit to the National Archaeological Museum, Athens, National Archaeological Museum in Athens, it was noticed by Greek politician Spyridon Stais as containing a gear, prompting the first study of the fragment by his cousin, Valerios Stais, the museum director. 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 ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
