| The unprecedented accuracy of modern laser range measurements and the stringent demands of precision orbit determination have led to the development of increasingly complex force models. The discovery of anomalous motions of the LAGEOS satellite has spurred interest in various esoteric force effects, including the radiation pressure imparted by the energy flux of the Earth. This topic is investigated in terms of orbit perturbations, effects in the presence of real data, and influence on the estimation of parameters.;Two related Earth radiation pressure models are examined. The nominal model assumes the Earth is a completely diffuse reflector and emitter of radiant energy. Satellite radiance data are used for the first time to devise an advanced model which realistically characterizes the directional and diurnal variations in the reflected component of Earth radiation pressure.;Various characteristics of the Earth radiation pressure force are examined, including variation over an orbit, variation with altitude, and the relative importance of the shortwave (reflected) and longwave (infrared) components. Albedo parameters are estimated from observations of a constellation of geodetic satellites. Consider analyses indicate the correlations between Earth radiation parameters and estimated parameters, including gravity coefficients.;Neither the diffuse nor the advanced Earth radiation pressure models can explain the observed mean secular decrease in the semimajor axis of LAGEOS, or any significant portion of the periodic excursions about this mean. Analyses of GEOS-1 and GEOS-2 data are used to verify the hypothesis that Earth radiation pressure can generate significant along-track accelerations on high eccentricity satellites passing through the Earth's shadow.;The advanced model usually engenders smaller orbit perturbations than the diffuse model, due to the diurnal variation in albedo. Some evidence exists to suggest that the advanced model may be somewhat more separable from competing nonconservative forces than the diffuse model. |
