“It seemed that the nearby and mysterious planet was resorting to tricks to hide the secrets kept beneath its cover of clouds. As the probe drew nearer, Venus’ gravitational field increased its speed. The Doppler effect altered the wavelength of the signals received on Earth. The radio operators needed to be particularly vigilant so that the information sent from the station consistently landed in the narrow “throat” of the ground-based receivers.” Boris Chertok
During 1965 through January 1966, several significant Soviet unmanned scientific missions were launched. Five of the missions will be covered in this episode. We will begin with the Soviet Luna program.