July 14, 1965 – first successful Mars probe captures images of the Red Planet
The first successful unmanned space probe Mars mission was achieved by the United States when Mariner 4 passed within 6,228 miles of the surface of Mars on July 14, 1965, providing 22 close-up images. Mariner 3 was launched on November 5th, 1964 but failed to reach Mars. Mariner 4 was launched a few weeks later on November 28, 1964.
Image credit: Wikipedia
Taken from Mariner 4, the first close-up image ever taken of Mars shows an area about 330 km across by 1200 km from limb to bottom of frame.