Zond Missions

The Russian word Zond means “probe,” like the French “Sonde,” and was used in the Soviet Union to refer to two different series of spacecraft. The first series consisted of three planetary probes. Zond 1 launched to Venus in mid-1964 and Zond 2 to Mars later that year, but both failed during flight. Zond 3 is thought to have been intended for Mars, but to have been delayed until too late to launch during the 1964 opportunity. It was instead used to test communications at planetary distances and to image the part of the lunar farside which had not been seen by Luna 3 in 1959.

Zond 3 was launched on July 18, 1965. Thirty-three hours later, it passed within 9200 km of the Moon and took 28 images on film. The film was processed onboard and scanned to convert the images for transmission. The images were transmitted several times at increasing distances to test communications and to correct any transmission losses. They showed the Mare Orientale region of the Moon and part of the South...