We suggest and use a test for evaluation of the accuracy of the harmonic coefficients in the Earth gravity field models (EMs), in which just the harmonics of the order mmin ≤ mm ≤ mmax and degree m ≤ 1 ≤ 1max are selected from the whole EMs. These parts will be called "frequency window(s)" (FWs). We treat the FWs of various recent EMs. One FW has been constructed solely from the resonant results for 12 ≤ m ≤ 15; we call it RFW. This RFW is used as a standard, sometimes independent, for comparing and testing other FWs. By means of the FWs, radius-vectors of the relevant parts of gecid are determined and compared to those of RFW. We intend to evaluate the differences between the EMs and to distinguish the models, FWs differ significantly from the RWF. and Celý článek bude publikován v Bull. Astron. Instit., sv..1985
The information on the accuracy of harmonic coefficients C1m, S1m as about a non-monotonic function of order m has been obtained from analysis of standard deviations of athe lumped coefficients compited from standart deviations of harmonic coefficients of various recent Earth gravity models as well as from resonant solutions for the individual orders. It is shown that the acuracy is lower for 8< m < 11 than for 12 < m < 15.
A draft of new laser geodynamic twin-satellite is presented. The aim of the experiment, theoretical basis and suggestions to orbit selection - with ~8 to 11 revs. „day^-1 - are described; some comments to a possible design of the satellites and to their separation are also given.