Radar astronomy and the Special Theory of Relativity

The measurements of planetary radar and lunar laser ranging are used to provide a complete experimental foundation of the Lorentz group of the Special Theory of Relativity. The practice of radar astronomy is followed such that the positions of the earth and that of the target planet are calculated as functions of ephemeris time using a Newtonian model of the solar system in first approximation; refined post-Newtonian models are used when higher precisions are required. The rate of clocks on the orbiting earth, as different from ephemeris time, and the speed of light as altered by gravitational fields, are corrected for as required by general relativity and verified experimentally to higher accuracies. This frees the conclusions with respect to special relativity from being derived by circuitous arguments via assuming the validity of general relativity , which itself is based on the validity of special relativity.