API Reference > imodeljs-common > Geometry > GeodeticEllipsoidProps GeodeticEllipsoidProps Interface This interface defines the mathematical model of the Earth shape in the form of an ellipsoid. There are various ways to define an ellipsoid but we have retained the definition based on the polar and equatorial radiuses. The other ellipsoid properties, such as flattening and inverse flattening, can be obtained using the simple equations that are defined at: https://en.wikipedia.org/wiki/Flattening and https://en.wikipedia.org/wiki/Earth_ellipsoid. Implemented by GeodeticEllipsoid Properties Name Type Description deprecated undefined | boolean If true then indicates the definition is deprecated. description undefined | string Description of the ellipsoid epsg undefined | number The EPSG code of the ellipsoid. equatorialRadius undefined | number The equatorial radius of the ellipsoid in meters id undefined | string Ellipsoid key name polarRadius undefined | number The polar radius of the ellipsoid in meters source undefined | string The textual description of the source of the ellipsoid definition. Defined in core/common/src/geometry/GeodeticEllipsoid.ts Line 18 Last Updated: 12 June, 2024