Mars Global Surveyor Mars Orbiter Camera: Interplanetary cruise through primary mission

Episodes of fluvial and volcanic activity in Mangala Valles, Mars

“…The first objective of this study is to map the Mangala Valles using Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) images (Malin et al, 2007) to achieve a level of detail comparable to Basilevsky et al (2008), but over the outflow channel system in its entirety. CTX images provide a spatial resolution (~6 m/pixel) and coverage that was not available to previous authors, who relied on High-Resolution Stereo Camera (HRSC) onboard Mars Express (Jaumann et al, 2007), Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) (Malin and Edgett, 2001), MGS Mars Orbiter Laser Altimeter (MOLA) (Smith et al, 2001), and Viking data . The resolution of CTX images allows for the detection of small, but key surface features that lead to an improved understanding of the stratigraphic relations of larger geologic units.…”

Eolian dunes and deposits in the western United States as analogs to wind-related features on Mars

“…The instruments on the MGS spacecraft (see MGS at W2) are providing data that continue to produce revisions to many of the Viking-based concepts for Mars (see Chapter 1). In particular, the 2 to 6 m/pixel images from the Mars Orbiter Camera (MOC; W24) on MGS provide views of eolian features that are comparable to aerial photographs of Earth (Malin el al., 1998;Edgett and Malin, 2000;Malin and Edgett, 2001;Edgett, 2002). The MOC images have not revealed "new" eolian features as much as they have clarified the perception of specific details for Martian sand dunes and dust deposits, including instances of eolian deposition and erosion that are comparable in scale to features on Earth, a change from the Viking view (Edgett and Malin, 2000).…”

“…The MOC images have not revealed "new" eolian features as much as they have clarified the perception of specific details for Martian sand dunes and dust deposits, including instances of eolian deposition and erosion that are comparable in scale to features on Earth, a change from the Viking view (Edgett and Malin, 2000). Comparison of MOC and the best Viking and Mariner 9 images have yet to reveal any observable movement of dune-forms on Mars (Zimbelman, 2000;Malin and Edgett, 2001). Classification of Martian dunes is now becoming feasible, although barchans (Figure 9.8; W25) and transverse dunes are still by far the most abundant Martian dune forms (Malin and Edgett, 2001).…”

“…Some material is blown away from the trapped sediments (Edgett, 2002), but MOC images have yet to reveal sufficient sand to form sand ramps or climbing dunes, as occur along terrestrial transport pathways. MOC images have revealed abundant eolian transverse ridges over much of the Martian surface, with wavelengths of tens to one hundred meters (Figure 9.9; W26; W27); these features could either be small dunes or large ripples, which form by different transport mechanisms (Malin et al, 1998;Malin and Edgett, 2001;Zimbelman and Wilson, 2002). Large eolian ripples on Earth have wavelengths of several to tens of meters and heights of 0.3 to 2 m and always involve a bimodal particle distribution of sand and granules to pebbles ; efforts are underway to test whether the smallest Martian transverse ridges are more likely ripples or dunes (Wilson et al, 2003).…”

“…Comparison of MOC and the best Viking and Mariner 9 images have yet to reveal any observable movement of dune-forms on Mars (Zimbelman, 2000;Malin and Edgett, 2001). Classification of Martian dunes is now becoming feasible, although barchans (Figure 9.8; W25) and transverse dunes are still by far the most abundant Martian dune forms (Malin and Edgett, 2001). Martian dune assemblages include an enormous erg (sand sea) surrounding the north polar cap.…”