WGS84datum

The WGS 84 datum is a geodetic reference system used to describe the size and shape of the Earth. Developed by the National Geospatial-Intelligence Agency (NGA) of the United States, it is based on a spheroid, which is an ellipsoid that approximates the actual shape of the Earth. This spheroid is defined by a semi-major axis of 6,378,136.84 meters and a semi-minor axis of 6,356,752.31 meters.

The WGS 84 datum was introduced in 1984 as a replacement for the World Geodetic System 1966 (WGS 66). The new reference system was designed to be more accurate and widely applicable, and it has since become the default geodetic system for many countries and international organizations. One of the key characteristics of WGS 84 is its use of the Earth's center of mass as its origin, rather than the Earth's center of figure, which is the center of the planet's gravity field.

The WGS 84 datum is used for a wide range of applications, including geolocation, navigation, and mapping. It provides a common reference system that allows for the precise location and orientation of objects and features on the Earth's surface. The datum is also used as a basis for other geodetic systems, such as the International Terrestrial Reference Frame (ITRF). Overall, the WGS 84 datum has become a crucial tool for many fields, including geospatial science, navigation, and surveying.