Z residuals (which we believe to be noise) of Magsat Dawn and Dusk data from the

New Magsat Data Set with respect to CMP3 (Terry Sabaka et al., A Comprehensive

Model of the Near-earth magnetic Field: Phase 3) by subtracting models of the main,

lithospheric(modeled by spherical harmonics to degree and order 42), magnetospheric,

ionospheric and toroidal field from the observed data