An Auxiliary Latitude also called the Reduced Latitude and denoted or . It gives the
Latitude on a Sphere of Radius for which the parallel has the same radius as the parallel of geodetic
latitude and the Ellipsoid through a given point. It is given by

In series form,

where

**References**

Adams, O. S. ``Latitude Developments Connected with Geodesy and Cartography with Tables, Including a Table for Lambert Equal-Area Meridional Projections.'' Spec. Pub. No. 67. U. S. Coast and Geodetic Survey, 1921.

Snyder, J. P. *Map Projections--A Working Manual.* U. S. Geological Survey Professional Paper 1395. Washington,
DC: U. S. Government Printing Office, p. 18, 1987.

© 1996-9

1999-05-26