Here we follow Rapp The alternative expressions for the flattenings would guard against large cancellations in numerical work.

In the following, a is the larger dimension (e.g. semimajor axis), whereas b is the smaller (semiminor axis).All flattenings are zero for a circle (a=b).The flattenings are related to other parameters of the ellipse.…

All flattenings are zero for a circle (a=b).The flattenings are related to other parameters of the ellipse.…

In he notes that General T. F. de Schubert had published a paper in which he claimed that the meridian arc data established that the equator of the Earth was elliptical in form.Clarke analyzed a larger data set and claimed that it fitted a tri-axial ellipsoid with a polar semi axis (b) and inverse flattenings of for which the difference in equatoreal semi-axes is approximately one mile.…