Mariner 6 and 7
In 1969 Mariner 6 and Mariner 7
completed the first dual mission to Mars
, flying by over the equator
and south polar regions and analysing atmosphere and surface with remote sensors as well as recording and relaying hundreds of pictures. By chance, both flew over cratered regions and missed both the giant northern volcanoes
and the equatorial grand canyon
discovered later. Their approach pictures did, however, show the dark features long seen from Earth, but no canals.
Mariner 7 made its closest fly-by of Mars (3,524 kilometers) on August 5, 1969.
The ultraviolet spectrometer onboard Mariners 6 and 7 was constructed by the Laboratory for Atmospheric and Space Physics.
The engineering model of Mariners 6 and 7 still exists, and is owned by the Jet Propulsion Laboratory. It is currently on loan to the Laboratory for Atmospheric and Space Physics, and is on display in the lab's lobby.
See also: Mariner program, Unmanned space missions