GRS-80

The Geodetic Reference System 1980 (GRS-80) is a globally accepted reference ellipsoid that provides a precise mathematical representation of the Earth's shape. Designed as an oblate spheroid, it defines the Earth's dimensions using parameters such as the equatorial radius, polar radius, flattening, and gravitational constants. GRS-80 serves as the foundation for several modern geodetic datums, including NAD83, and has significantly influenced the development of WGS 84. Unlike a perfect sphere, it accounts for the Earth's equatorial bulge caused by its rotation, making it far more accurate for geospatial calculations. This standardized model enables precise coordinate referencing, distance and area measurements, satellite positioning, and spatial analysis. GRS-80 is widely used in geographic information systems (GIS), land surveying, mapping, remote sensing, and navigation. By providing a consistent global reference framework, it ensures the accuracy, compatibility, and interoperability of geospatial data across regional and international applications.