Definition of the WGS 84

What is WGS84 and explain?

The World Geodetic System 1984 (WGS84) is a datum featuring coordinates that change with time. WGS84 is defined and maintained by the United States National Geospatial-Intelligence Agency (NGA). It is consistent, to about 1cm, with the International Terrestrial Reference Frame (ITRF).

What are the dimensions of WGS84?

The WGS 84 datum surface is an oblate spheroid with equatorial radius a = 6378137 m at the equator and flattening f = 1/298.257223563. The refined value of the WGS 84 gravitational constant (mass of Earth’s atmosphere included) is GM = 3986004.418×10⁸ m³/s².

What four 4 different things comprise WGS84?

Defining Parameters: WGS 84 identifies four defining parameters. These are the semi-major axis of the WGS 84 ellipsoid, the flattening factor of the Earth, the nominal mean angular velocity of the Earth, and the geocentric gravitational constant as specified below.

What is WGS84 measured in?

The WGS84 Coordinate Systems adds Greenwich as the starting point (prime meridian) for the longitude (0°) and sets the units in degrees (°). This coordinate system also has a unique reference code, the so-called EPSG code, which is 4326.
 

Why does GPS use WGS84?

Pinpoint Your Position Using WGS84



Because the Earth is curved – and in GIS we deal with flat map projections – we need to accommodate both the curved and flat views of the world. Surveyors and geodesists have accurately defined locations on Earth.
 

What is the difference between WGS84 and UTM?

The difference is that WGS 84 is a geographic coordinate system, and UTM is a projected coordinate system. Geographic coordinate systems are based on a spheroid and utilize angular units (degrees).
 

Is WGS 84 a meter?

WGS 84 by itself is not measured in meters (as a geographic reference system); however, it forms the datum for many projections (often UTM for example). The projection transforms the lat long pairs onto a Cartesian plane, measured in any unit, in this case meters, but this transformation is specific to the projection.
 

Is WGS 84 equal area?

2) WGS 1984 Behrmann (World): This is an equal area projection. Note that the 15×15 degree graticule cells are now compressed to show the smaller areas north or south of the Equator.

Is WGS 84 a decimal degree?

Geographic coordinates (WGS84)



On this page the latitude is given in decimal degrees from -90° to +90°, it would also be possible to give from 90° south to 90° north. The length is given in -180° to +180° East, instead of 180° West to 180° East.

What is WGS84 in maritime?

A consistent set of parameters describing the size and shape of the Earth, positions of a network of points with respect to the centre of mass of the Earth, transformations from major geodetic datums and the potential of the Earth. WGS 84. The coordinate system used by GPS.
 

Where is the WGS84 datum used for measurements?

WGS84 is the default standard datum for coordinates stored in recreational and commercial GPS units. Users of GPS are cautioned that they must always check the datum of the maps they are using.

What is the difference between WGS84 and ED50?

Datum shift between ED50 and WGS 84



Moving southwards, the latitude lines on ED50 gradually become further south than the WGS 84 lines, and are around 100 m south in the Mediterranean Sea. This means that if the lines are further west, the longitude value of any given point becomes more easterly.