M. M. Denisov

The mathematical model of laser ranging of geostationary spacecraft is build. This model takes into account, that in virtue of the rotation of Earth the movement low of electromagnetic pulses are differ from that in inertial frame of referece. Spacecraft is placed on the geostationary orbit in plane of equator. It moves around Earth with angular frequency, which coincides with that of Earth. Therefore it is a part of rotating frame of reference of Earth, which is distant on RS≈ 42300 km from its center. Laser station is placed on the surface of Earth in the point with spherical coordinates θ0 and φ0. In t =tb laser station emits the light pulse to spacecraft. This pulse reflects at the time t = tr from retroreflectors of spacecraft and come back to laser station at the time t = tf. The equations of isotropic geodetic movement of the General Relativity are solved. They gave the low of light pulse movement in this experiment. This circumstance permits us to find on the laser station the tangent vectors N and M to rays, on which the light pulse should be emitted from laser ranging station to the retroreflector of geostationary spacecraft, and the direction, on which it return to laser ranging station. The calculation of the angle between the direction, on which the light pulse should be emitted from laser ranging station to the re-troreflector of geostationary spacecraft, and the direction, on which it return to laser ranging station, is carried out. It is shown, that the minimum value of the angle (αmin=3.5 arcseconds) is reached by the ranging of the geostationary spacecraft placed on the zenith. Maximum value (αmax=4.0 arcseconds) is reached, when laser ranging station is placed on the equator, and the ranging is realized on the ultimate angle distance: 15º from local horizon. The experiment for the measurement this Einstein-s General Relativity prediction is proposed.