Mariner 4 was the fourth in a series of spacecraft used for planetary exploration in a flyby mode and represented the first successful flyby of the planet Mars, returning the first pictures of the martian surface.
Date: 28 Nov 1964
It was designed to conduct closeup scientific observations of Mars and to transmit these observations to earth. Other mission objectives were to perform field and particle measurements in interplanetary space in the vicinity of Mars and to provide experience in and knowledge of the engineering capabilities for interplanetary flights of long duration.
Image Credit: NASA