  We examine how the new forthcoming Earth gravity models from the CHAMP and,
especially, GRACE missions could improve the measurement of the general
relativistic Lense-Thirring effect according to the various kinds of
observables which could be adopted. In a very preliminary way, we use the
recently released EIGEN2 CHAMP-only and GRACE01S GRACE-only Earth gravity
models in order to assess the impact of the mismodelling in the even zonal
harmonic coefficients of geopotential which represents one of the major sources
of systematic errors in this kind of measurement.
