Intercrater plains and heavily cratered terrain typical of much of Mercury outside the area affected by the formation of the Caloris basin are shown in this image (FDS 166738) taken during the spacecraft's second encounter with Mercury. Abundant shallow elongate craters and crater chains are present on the intercrater plains. North is to the top of this image, centered at 56 degrees S, 128 degrees W and 400 kilometers across.
The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.