World Geodetic System | EPFL Graph Search

Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?

Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur GraphSearch.

Découvrez-en plus sur les applications Graph.

The World Geodetic System (WGS) is a standard used in cartography, geodesy, and satellite navigation including GPS. The current version, WGS 84, defines an Earth-centered, Earth-fixed coordinate system and a geodetic datum, and also describes the associated Earth Gravitational Model (EGM) and World Magnetic Model (WMM). The standard is published and maintained by the United States National Geospatial-Intelligence Agency. Efforts to supplement the various national surveying systems began in the 19th century with F.R. Helmert's famous book Mathematische und Physikalische Theorien der Physikalischen Geodäsie (Mathematical and Physical Theories of Physical Geodesy). Austria and Germany founded the Zentralbüro für die Internationale Erdmessung (Central Bureau of International Geodesy), and a series of global ellipsoids of the Earth were derived (e.g., Helmert 1906, Hayford 1910/ 1924). A unified geodetic system for the whole world became essential in the 1950s for several reasons: International space science and the beginning of astronautics. The lack of inter-continental geodetic information. The inability of the large geodetic systems, such as European Datum (ED50), North American Datum (NAD), and Tokyo Datum (TD), to provide a worldwide geo-data basis Need for global maps for navigation, aviation, and geography. Western Cold War preparedness necessitated a standardised, NATO-wide geospatial reference system, in accordance with the NATO Standardisation Agreement In the late 1950s, the United States Department of Defense, together with scientists of other institutions and countries, began to develop the needed world system to which geodetic data could be referred and compatibility established between the coordinates of widely separated sites of interest. Efforts of the U.S. Army, Navy and Air Force were combined leading to the DoD World Geodetic System 1960 (WGS 60). The term datum as used here refers to a smooth surface somewhat arbitrarily defined as zero elevation, consistent with a set of surveyor's measures of distances between various stations, and differences in elevation, all reduced to a grid of latitudes, longitudes, and elevations.

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Publications associées (1)

Concepts associés (26)

Cours associés (7)

Séances de cours associées (62)

Accretion disks surrounding compact objects, and other environmental factors, deviate satellites from geodetic motion. Unfortunately, setting up the equations of motion for such relativistic trajector

AMER PHYSICAL SOC2022

Contrôle et surveillance des barrages et des structures hydrauliques

Couvre le contrôle et la surveillance des barrages et des structures hydrauliques.

Coordonnées et systèmes de projection

Explore les échelles, les systèmes de coordonnées, les projections cartographiques et les références de positionnement légales.

Localisation : Concept

Explique le suivi par satellite pour la position de l'utilisateur et les systèmes de coordonnées GPS.

Earth ellipsoid

An Earth ellipsoid or Earth spheroid is a mathematical figure approximating the Earth's form, used as a reference frame for computations in geodesy, astronomy, and the geosciences. Various different ellipsoids have been used as approximations. It is a spheroid (an ellipsoid of revolution) whose minor axis (shorter diameter), which connects the geographical North Pole and South Pole, is approximately aligned with the Earth's axis of rotation.

World Geodetic System

Physical geodesy

Physical geodesy is the study of the physical properties of Earth's gravity and its potential field (the geopotential), with a view to their application in geodesy. Traditional geodetic instruments such as theodolites rely on the gravity field for orienting their vertical axis along the local plumb line or local vertical direction with the aid of a spirit level. After that, vertical angles (zenith angles or, alternatively, elevation angles) are obtained with respect to this local vertical, and horizontal angles in the plane of the local horizon, perpendicular to the vertical.

ENV-140: Fundamentals of geomatics

Bases de la géomatique pour les ingénieurs civil et en environnement. Présentation des méthodes d'acquisition, de gestion et de représentation des géodonnées. Apprentissage pratique avec des méthodes

ENV-340: Fundamentals of satellite positioning

Bases des références géodésiques, principe de mesure utilisé en localisation par satellites et de l'estimation de la qualité de positions GNSS (Global Navigation Satellites Systems).

MATH-213: Differential geometry

Ce cours est une introduction à la géométrie différentielle classique des courbes et des surfaces, principalement dans le plan et l'espace euclidien.