Abstract
Name for a corpus similar to a sphere or a surface which do not deviate much from a sphere.
Particular
Name for a rotation ellipsoid. In geodesy and cartography this is the standard corpus of the Earth which mathematics deals with; in general a rotation ellipsoid (flattened at the poles) with the semi-axes a and b (a > b).
This rotation ellipsoid has the parameter representation
fx(u,v) = a * cos(u) * cos(v) ,
fy(u,v) = a * sin(u) * cos(v) ,
fz(u,v) = b * sin(v)
with - / 2 ≤ v ≤
/ 2 and -
≤ u ≤
.
The »official maps« of numerous European countries are based on the Earth ellipsoid by Bessel (1841). This Earth ellipsoid have the semi-axes
a = 6,377,397.15500 m and b = 6,356,078.96325 m .
In 1924 the »Association Géodésique« suggested the International Earth Ellipsoid by Hayford (USA) which has the semi-axes
a = 6,378,388.00000 m and b = 6,356,911.94613 m .