This book gathers the proceedings of a symposium on Dynamics of satellites which took place in Prague in May 1969 during the twelfth COSPAR meeting. This symposium was sponsored by the International Astronomical Union, the International Association of Geodesy, the International Union of Theoretical and Applied Mechanics and COSPAR (Committee on Space Research). The organizing committee was composed of Dr. KOVALEVSKY chair­ man, Dr. Yu. V. BATRAKOV representing IAU, Dr. A. H. COOK for lAG, Dr. D. KING-HELE for COSPAR, Prof. M. Roy for IUTAM and Dr. ROSENBERG. I wish to take advantage of the opportunity to thank, on behalf of all the participants, the organizing committee members, Prof. BUCHAR, Dr. RAJSK:I and Dr. SEHNAL, for the kindness and efficiency of their welcome. The interpreters who translated with virtuosity during the whole symposium also deserve our gratitude. I am grateful also for the care and skill with which Springer-Verlag has printed this volume.

Theory of the Motion of an Artificial Satellite.- Advances in Rapid Orbit Prediction and Applications to Satellite Visibility Studies.- Determination of the most Probable Elements of a Satellite Orbit from Incomplete Systems of Elements.- On the Influence of Distribution of Observations on Accuracy of Orbital Elements of the Earth's Artificial Satellites.- The Use of Ellipsoidal Harmonics for the Representation of the Geopotential.- Computer Derivation of Short-Period Lunar Perturbations.- Perturbations du Second Ordre d'un Satellite Artificiel de la Terre.- A Short Study on the Motion of Artificial Satellites of Mercury and Venus.- Results on the Mass and the Gravitational Field of the Moon as Determined from Dynamics of Lunar Satellites.- The Use of Brown's Lunar Theory in Lunar Satellite Perturbations by Sun and Earth.- The Determination of Planetary Masses from Radio Tracking of Space Probes and Planetary Radar.- Satellite Trajectory Determination and their Expected Errors OGO-IV, GEOS-I.- Revised Values for Coefficients of Zonal Harmonics in the Geopotential.- Improved Values for the Tesseral Harmonics of the Geopotential and Station Coordinates.- On the Determination of Parameters of the Earth's Figure from Satellite Orbit Dynamics.- Accuracy of Satellite Orbits Obtainable by Synchronous Satellite Tracking.- Resonant Satellite Geodesy by High Speed Analysis of Mean Kepler Elements.- Resultats du Dépouillement des Mesures Laser en Géodésie Semi-Dynamique.- Short Arc Optical Survey of the GEOS North American Tracking Network.- Traitement des Mesures Doppler en Géodésie Semi-Dynamique.- Comparative Analysis of Different Results on the European Datum from Spatial Geodesy.- Comparisons and Combinations of Geodetic Parameters Estimated from Dynamic andGeometric Satellite Solutions and from Mariner Flights.- Tidal Potential with Location-Dependent Amplitude and Phase angle.- On the Determination of Field Parameters Using a generalized Fourier-Analysis.- Correlation Between the Solar Activity Indices and the Use of these Indices in the Study of Motion of the Earth Satellites.- New Investigations of Motion of an Artificial Satellite About its Center of Mass.- Dynamics of Spin-Stabilized Flexible Satellites of Crossed- Dipole Configuration.- Comparison of Air Densities Derived from the Orbits of 1966-51A, B and C.- The Use of AES Orbits Evolution Data for Refinement of Some Geophysical Parameters.- Analysis of the Atmospheric Drag of the Echo 1 Satellite Using the PERLO Orbital Period Determination Program.- The Upper Atmosphere and its Influence on Satellite Orbits.- Radiation Pressure Effects in the Motion of Artificial Satellites.- Air Drag and Solar Radiation Pressure Effects on Close Earth Satellites.- Effets de L'Atmosphère et de la Pression Réémise à Haute Altitude.- The Earth's Shadowing Effects in the Short-Periodic Perturbations of Satellite Orbits.- Earth-Reflected Radiation Pressure.- The Orbital Acceleration of High Balloon Satellites.- Earth Albedo Effects on the Orbital Variations of Echo I and PAGEOS I.