1895-1979 ancient artificialsatellites artificialsatellitesinnavigation artificialsatellitesorbits astrology astronomy basic(computerprogramlanguage) bifurcationtheory celestialmechanics controlsystems cycles dataprocessing differentiabledynamicalsystems dynamics geostationarysatellites globalpositioningsystem history immanuel mathematicaloptimization measurement microcomputers miscellanea orbit orbitdetermination planets spacevehicles three-bodyproblem tracking velikovsky