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Geographic Coordinate System
The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms the basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system, the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid), as different datums will yield different latitude and longitude values for the same location. History The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene, who composed his now-lost ''Geography'' at the Library of Alexandria in the 3rd century  ...
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Library Of Alexandria
The Great Library of Alexandria in Alexandria, Egypt, was one of the largest and most significant libraries of the ancient world. The Library was part of a larger research institution called the Mouseion, which was dedicated to the Muses, the nine goddesses of the arts.Murray, S. A., (2009). The library: An illustrated history. New York: Skyhorse Publishing, p.17 The idea of a universal library in Alexandria may have been proposed by Demetrius of Phalerum, an exiled Athenian statesman living in Alexandria, to Ptolemy I Soter, who may have established plans for the Library, but the Library itself was probably not built until the reign of his son Ptolemy II Philadelphus. The Library quickly acquired many papyrus scrolls, owing largely to the Ptolemaic kings' aggressive and well-funded policies for procuring texts. It is unknown precisely how many such scrolls were housed at any given time, but estimates range from 40,000 to 400,000 at its height. Alexandria came to be regarde ...
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Asia Minor
Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The region is bounded by the Turkish Straits to the northwest, the Black Sea to the north, the Armenian Highlands to the east, the Mediterranean Sea to the south, and the Aegean Sea to the west. The Sea of Marmara forms a connection between the Black and Aegean seas through the Bosporus and Dardanelles straits and separates Anatolia from Thrace on the Balkan peninsula of Southeast Europe. The eastern border of Anatolia has been held to be a line between the Gulf of Alexandretta and the Black Sea, bounded by the Armenian Highlands to the east and Mesopotamia to the southeast. By this definition Anatolia comprises approximately the western two-thirds of the Asian part of Turkey. Today, Anatolia is sometimes considered to be synonymous with Asia ...
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Rhodes
Rhodes (; el, Ρόδος , translit=Ródos ) is the largest and the historical capital of the Dodecanese islands of Greece. Administratively, the island forms a separate municipality within the Rhodes regional unit, which is part of the South Aegean administrative region. The principal town of the island and seat of the municipality is Rhodes. The city of Rhodes had 50,636 inhabitants in 2011. In 2022 the island has population of 124,851 people. It is located northeast of Crete, southeast of Athens. Rhodes has several nicknames, such as "Island of the Sun" due to its patron sun god Helios, "The Pearl Island", and "The Island of the Knights", named after the Knights of Saint John of Jerusalem, who ruled the island from 1310 to 1522. Historically, Rhodes was famous for the Colossus of Rhodes, one of the Seven Wonders of the Ancient World. The Medieval Old Town of the City of Rhodes has been declared a World Heritage Site. Today, it is one of the most popular tourist destina ...
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Cape Verde
, national_anthem = () , official_languages = Portuguese , national_languages = Cape Verdean Creole , capital = Praia , coordinates = , largest_city = capital , demonym = Cape Verdean or Cabo Verdean , ethnic_groups_year = 2017 , government_type = Unitary semi-presidential republic , leader_title1 = President , leader_name1 = José Maria Neves , leader_title2 = Prime Minister , leader_name2 = Ulisses Correia e Silva , legislature = National Assembly , area_rank = 166th , area_km2 = 4033 , area_sq_mi = 1,557 , percent_water = negligible , population_census = 561,901 , population_census_rank = 172nd , population_census_year = 2021 , population_density_km2 = 123.7 , population_density_sq_mi = 325.0 , population_density_rank = 89th , GDP_PPP ...
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Canary Islands
The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocco. They are the southernmost of the autonomous communities of Spain. The islands have a population of 2.2 million people and they are the most populous special territory of the European Union. The seven main islands are (from largest to smallest in area) Tenerife, Fuerteventura, Gran Canaria, Lanzarote, La Palma, La Gomera, and El Hierro. The archipelago includes many smaller islands and islets, including La Graciosa, Alegranza, Isla de Lobos, Montaña Clara, Roque del Oeste, and Roque del Este. It also includes a number of rocks, including those of Salmor, Fasnia, Bonanza, Garachico, and Anaga. In ancient times, the island chain was often referred to as "the Fortunate Isles". The Canary Islands are the southernmost region of Spain, and ...
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Fortunate Isles
The Fortunate Isles or Isles of the Blessed ( grc, μακάρων νῆσοι, ''makárōn nêsoi'') were semi-legendary islands in the Atlantic Ocean, variously treated as a simple geographical location and as a winterless earthly paradise inhabited by the heroes of Greek mythology. The related idea of Brasil and other islands in Celtic mythology are sometimes conflated with the Greek sense of islands in the western Mediterranean: Sicily, the Aeolian Islands, the Aegadian Islands or other smaller islands of Sicily. Later on, the islands were said to lie in the Western Ocean near the encircling River Oceanus; Madeira, the Canary Islands, the Azores, Cape Verde, Bermuda, and the Lesser Antilles have sometimes been cited as possible matches. Legend According to Greek mythology, the islands were reserved for those who had chosen to be reincarnated three times, and managed to be judged as especially pure enough to gain entrance to the Elysian Fields all three times. Accounts ...
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Prime Meridian
A prime meridian is an arbitrary meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. Together, a prime meridian and its anti-meridian (the 180th meridian in a 360°-system) form a great circle. This great circle divides a spheroid, like the Earth, into two hemispheres: the Eastern Hemisphere and the Western Hemisphere (for an east-west notational system). For Earth's prime meridian, various conventions have been used or advocated in different regions throughout history. The Earth's current international standard prime meridian is the IERS Reference Meridian. It is derived, but differs slightly, from the Greenwich Meridian, the previous standard. A prime meridian for a planetary body not tidally locked (or at least not in synchronous rotation) is entirely arbitrary, unlike an equator, which is determined by the axis of rotation. However, for celestial objects that are tidally locked (more specifically, synchronous), th ...
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Equirectangular Projection
The equirectangular projection (also called the equidistant cylindrical projection or la carte parallélogrammatique projection), and which includes the special case of the plate carrée projection (also called the geographic projection, lat/lon projection, or plane chart), is a simple map projection attributed to Marinus of Tyre, who Ptolemy claims invented the projection about AD 100. The projection maps meridians to vertical straight lines of constant spacing (for meridional intervals of constant spacing), and circles of latitude to horizontal straight lines of constant spacing (for constant intervals of parallels). The projection is neither equal area nor conformal. Because of the distortions introduced by this projection, it has little use in navigation or cadastral mapping and finds its main use in thematic mapping. In particular, the plate carrée has become a standard for global raster datasets, such as Celestia, NASA World Wind, the USGS Astrogeology Research Progra ...
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Marinus Of Tyre
Marinus of Tyre ( grc-gre, Μαρῖνος ὁ Τύριος, ''Marînos ho Týrios'';  70–130) was a Greek geographer, cartographer and mathematician, who founded mathematical geography and provided the underpinnings of Claudius Ptolemy's influential ''Geography''. Life Marinus was originally from Tyre in the Roman province of Syria. His work was a precursor to that of the great geographer Claudius Ptolemy, who used Marinus' work as a source for his ''Geography'' and acknowledges his great obligations to him. Ptolemy said, "Marinus says of the merchant class generally that they are only intent on their business, and have little interest in exploration, and that often through their love of boasting they magnify distances."Ptolemy, "33"
Later, Marinus was also cited by the

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Dead Reckoning
In navigation, dead reckoning is the process of calculating current position of some moving object by using a previously determined position, or fix, and then incorporating estimates of speed, heading direction, and course over elapsed time. The corresponding term in biology, used to describe the processes by which animals update their estimates of position or heading, is path integration. Dead reckoning is subject to cumulative errors. Advances in navigational aids that give accurate information on position, in particular satellite navigation using the Global Positioning System, have made simple dead reckoning by humans obsolete for most purposes. However, inertial navigation systems, which provide very accurate directional information, use dead reckoning and are very widely applied. Etymology The term "dead reckoning" was not originally used to abbreviate "deduced reckoning," nor is it a misspelling of the term "ded reckoning." The use of "ded" or "deduced reckoning" ...
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Lunar Eclipse
A lunar eclipse occurs when the Moon moves into the Earth's shadow. Such alignment occurs during an eclipse season, approximately every six months, during the full moon phase, when the Moon's orbital plane is closest to the plane of the Earth's orbit. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned (in syzygy) with Earth between the other two, which can happen only on the night of a full moon when the Moon is near either lunar node. The type and length of a lunar eclipse depend on the Moon's proximity to the lunar node. When the moon is totally eclipsed by the Earth, it takes on a reddish color that is caused by the planet when it completely blocks direct sunlight from reaching the Moon surface, as only the light reflected from the lunar surface has been refracted by Earth's atmosphere. This light appears reddish due to the Rayleigh scattering of blue light, the same reason sunrise and sunsets are more orange than during the day. Un ...
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