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Facebook Twitter World Geodetic System. The World Geodetic System (WGS) is a standard for use in cartography, geodesy, and navigation.

World Geodetic System

It comprises a standard coordinate system for the Earth, a standard spheroidal reference surface (the datum or reference ellipsoid) for raw altitude data, and a gravitational equipotential surface (the geoid) that defines the nominal sea level. The latest revision is WGS 84 (aka WGS 1984, EPSG:4326), established in 1984 and last revised in 2004.[1] Earlier schemes included WGS 72, WGS 66, and WGS 60. WGS 84 is the reference coordinate system used by the Global Positioning System. Main parameters[edit] Map–territory relation. Glossary of Cartographic Terms - Perry-Castañeda Map Collection - UT Library Online. Glossary of Cartographic Terms From: Maps for America.

Glossary of Cartographic Terms - Perry-Castañeda Map Collection - UT Library Online

Third Edition. accuracy Degree of conformity with a standard. Accuracy relates to the quality of a result and is distinguished from precision which relates to the quality of the operation by which the result is obtained. adjustment Process designed to remove inconsistencies in measured or computed quantities by applying derived corrections to compensate for random or accidental errors. adjustment, land- line Positioning land lines on a map to indicate their true, theoretical, or approximate location relative to the adjacent terrain and culture, by reconciling the information shown on Bureau of Land Management plats and field records with the ground evidence of the location of the lines. adjustment, standard accuracy Adjustment of a survey resulting in values for positions and (or) elevations that comply with the National Map Accuracy Standards. aerotriangulation alidade altimeter azimuth backshore base map See: map, base.

List of cartographers. Early world maps. Early world maps cover depictions of the world from the Iron Age to the Age of Discovery and the emergence of modern geography during the early modern period.

Early world maps

Antiquity[edit] Babylonian Imago Mundi (c. 600 BCE)[edit] A Babylonian world map, known as the Imago Mundi, is commonly dated to the 6th century BCE.[1][2] The map as reconstructed by Eckhard Unger shows Babylon on the Euphrates, surrounded by a circular landmass showing Assyria, Urartu[3] and several cities, in turn surrounded by a "bitter river" (Oceanus), with seven islands arranged around it so as to form a seven-pointed star. The accompanying text mentions seven outer regions beyond the encircling ocean. Cartography. Cartography (from Greek χάρτης khartēs, "map"; and γράφειν graphein, "write") is the study and practice of making maps.


Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively. The fundamental problems of traditional cartography are to:[citation needed] Set the map's agenda and select traits of the object to be mapped. This is the concern of map editing. Traits may be physical, such as roads or land masses, or may be abstract, such as toponyms or political boundaries.Represent the terrain of the mapped object on flat media.

Modern cartography is largely integrated with geographic information science (GIScience) and constitutes many theoretical and practical foundations of geographic information systems. Introducing Google Maps Gallery: Unlocking the World’s Maps. Posted by Jordan Breckenridge, Google Maps, Product Manager Editor's note: Last year we introduced the Google Maps Engine public data program, which lets organizations easily publish their map content online.

Introducing Google Maps Gallery: Unlocking the World’s Maps

Today, we’re expanding on that program and letting organizations improve the discoverability of their maps. Chart Porn. Gerardus Mercator. Gerardus Mercator (born 5 March 1512 in Rupelmonde, County of Flanders (in modern Belgium), died 2 December 1594 in Duisburg, United Duchies of Jülich-Cleves-Berg, (modern-day Germany)) was a cartographer, philosopher and mathematician.

Gerardus Mercator

He is best known for his work in cartography, in particular the world map of 1569 based on a new projection which represented sailing courses of constant bearing as straight lines. He was the first to use the term "atlas" for a collection of maps. Life and works[edit] Mercator was charged with heresy in 1544, on the basis of his sympathy for Protestant beliefs and suspicions about his frequent travels. [note 1] He was in prison for seven months before the charges were dropped—possibly because of intervention from the university authorities.[2] Terrestrial globe by Mercator dating from 1541. In 1552, he moved to Duisburg, one of the major cities in the Duchy of Cleves, and opened a cartographic workshop where he completed a six-panel map of Europe in 1554. Mercator projection. Mercator projection of the world between 82°S and 82°N.

Mercator projection

Mercator world map (Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendate Accommodata (1569) For higher resolution and coloured images see Mercator 1569 world map. Mercator. Mercator map. Atlas of the internet. Cyber Badger Research Blog. Transverse Mercator projection. A transverse Mercator projection Standard and transverse aspects[edit]

Transverse Mercator projection

Infographic: An Amazing Atlas of the World Wide Web. Dafna Aizenberg's Atlas of the World Wide Web visualizes data taken from the internet.

Infographic: An Amazing Atlas of the World Wide Web

Image: Dafna Aizenberg A graphic that looks at global IP address distribution. Image: Dafna Aizenberg More developed countries tend to be darker in color. Image: Dafna Aizenberg China's color has darkened over time. Image: Dafna Aizenberg Fastest internet connections around the world. Image: Dafna Aizenberg A close-up. Countries that are imposing limitations on free, uncensored internet access. An Atlas of Cyberspaces - Topology Maps.