Mariner 4 was the fourth in a series of spacecraft intended for planetary exploration in “fly-by” mode. It was designed to conduct closeup scientific observations of Mars and to transmit these observations to Earth. Mariner 4 performed the first successful flyby of the planet Mars, returning the first close-up pictures of the Martian surface. It captured the first images of another planet ever returned from deep space impacting the scientific community’s view of life on Mars.