|Mariner 6 flies within 3,411
kilometers (2,120 miles) of Mars. With Mariner 7's flyby on August
5, the twin craft complete the first dual mission to Mars.
They fly over the equator and south polar regions and analyze the
Martian atmosphere and surface with remote sensors, as well as record
and relay hundreds of pictures. The craft take 143 pictures on approach
and 55 close-ups of the surface, revealing cratered deserts, depressions
with no craters, huge concentrically terraced impact regions and collapsed