United States
On November 28, 1964, NASA launched Mariner 4 toward Mars from Cape Kennedy, Florida. The spacecraft was designed to perform a flyby of the planet and return the first close-up images of its surface. After a journey of about seven and a half months, Mariner 4 passed Mars in July 1965 and transmitted a series of grainy but groundbreaking photographs. The images revealed a heavily cratered landscape and fewer signs of a thick atmosphere or active geology than some scientists had hoped. The mission proved that long-distance planetary exploration and data transmission were technically feasible. It laid important groundwork for later Mars missions, including orbiters, landers, and rovers.
