Source: wikibot/hayford-ellipsoid

= Hayford ellipsoid
{wiki=Hayford_ellipsoid}

The Hayford ellipsoid, also known as the Hayford or International Ellipsoid of 1924, is a mathematical model of the Earth's shape that represents the Earth as an oblate spheroid. This ellipsoid was developed by the American geodesist, William H. Hayford, and was widely used for geodetic surveys and mapping in the early to mid-20th century.