Mariner 9 Images
The Labyrinth Area of Western Valles Marineris on Mars
Mariner 9 view of the "labyrinth" at the western end of Vallis Marineris on
Mars. Linear graben, grooves, and crater chains dominate this region, along with a number
of flat-topped mesas. The image is roughly 400 km across, centered at 6 S, 105 W, at the
edge of the Tharsis bulge. North is up. (Mariner 9, MTVS 4187-45)
Promethei Sinus Near Mars' South Pole
Wide-angle Mariner 9 image of Promethei Sinus, centered at 70 S, 259 W. The area is
typified by the large splotchy craters seen here. Note that the dark areas tend to lie on
the downwind side of the crater floors. The frame is 450 km from top to bottom. (Mariner
9, MTVS 4211-9)
Central Caldera of Olympus Mons on Mars
Mariner 9 image of the central caldera of
the Martian volcano, Olympus Mons. the basic morphology is similar to terrestrial
calderas, although the scale is much larger. The smallest (and youngest) collapse pit, at
right, is 30 km across. Concentric fractures and terraces are visible in the larger parts
of the caldera. The caldera is about 29 km above the mean Martian surface. North is at
7:00. (Mariner 9, MTVS 4265-52)
Pits and Depression Features Near the South Pole of Mars
High-resolution Mariner 9 image showing an area of irregular pits and depressions near the
south pole of Mars. The depressions have flat floors and smooth walls. Similar features
are formed on Earth by the scouring action of wind. The largest terrestrial example of
these deflation hollows, found in the desert of north central China, are still much
smaller than those shown here. The frame is about 75 km from top to bottom and is centered
at 74 S, 7 W. (Mariner 9, MTVS 4270-24)
Mars' North Polar Cap
Mariner 9 image of the north polar cap of Mars. The image was taken on 12 October 1972,
about one-half Martian month after summer solstice, at which time the cap had reached its
minimal extent. The cap is about 1000 km across. The interior dark markings are frost-free
sun-facing slopes. A smooth layered sedimentary deposit underlies the cap. The image is
centered at 89 N, 200 W. (Mariner 9, MTVS 4297-47)