Reference Ellipsoid

In geodesy, a reference ellipsoid is a mathematically-defined surface that approximates the geoid, the truer figure of the Earth, or other planetary body. Because of their relative simplicity, reference ellipsoids are used as a preferred surface on which geodetic network computations are performed and point coordinates such as latitude, longitude, and elevation are defined.

Read more about Reference Ellipsoid:  Ellipsoid Parameters, Coordinates, Historical Earth Ellipsoids, Ellipsoids For Other Planetary Bodies

Famous quotes containing the word reference:

    In sum, all actions and habits are to be esteemed good or evil by their causes and usefulness in reference to the commonwealth, and not by their mediocrity, nor by their being commended. For several men praise several customs, and, contrarily, what one calls vice, another calls virtue, as their present affections lead them.
    Thomas Hobbes (1579–1688)