Bessel Ellipsoid - The Bessel and GPS Ellipsoids

The Bessel and GPS Ellipsoids

The Bessel ellipsoid fits especially well to the geoid curvature of Europe and Eurasia. Therefore it is optimal for National survey networks in these regions, despite of the fact that its axes are about 700 m shorter than that of the mean Earth ellipsoid derived by satellites.

Below the are the two axes a, b and the flattening ƒ = (a − b)/a. For comparison, the data of the modern World Geodetic System WGS84 are shown, which is mainly used for modern surveys and the GPS system.

• Bessel ellipsoid 1841 (defined by log a and ƒ):
  • a = 6,377,397.155 m
  • ƒ = 1 / 299.1528153513233 (0.003342 773154 ± 0.000005)
  • b = 6,356,078.963 m.

• Earth ellipsoid WGS84 (defined directly by a and ƒ):
  • a = 6,378,137.0 m
  • ƒ = 1 / 298.257223563
  • b = 6,356,752.30 m.