This is how Deputy Chief Designer for OKB-1, Boris Chertok described the launch of Mars 3. “The red disk of the Sun was just touching the horizon and dramatically illuminated the rocket as it lifted off with a roar. Separation of the stages took place like a color animation display against the background of the darkened sky.”
Mariner 8 and 9 were virtually identical and designed to continue the atmospheric studies begun by Mariner 6 and 7, and to hopefully map over 70% of the Martian surface.
Mariner 4’s primary objective was to conduct closeup scientific observations of Mars and to transmit these observations to Earth. Additional goals included performing field and particle measurements in interplanetary space, and providing experience and knowledge of engineering capabilities for interplanetary flights of long duration…
“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