Happy New Year From Mars

A few new HiRISE images of Mars from the UA's Lunar and Planetary Lab to start the new year:

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  • NASA/JPL/University of Arizona

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  • NASA/JPL/University of Arizona

The upper shot shows dark sand covering bright bedrock in the Terra Meridiani region of Mars.

Nathan Bridges of the LPL tells us:

The MER Opportunity rover is currently exploring Meridiani, but is located about 500 kilometers to the west-southwest from here (as of 2007).

There are three broad classes of terrain in this image. The regular spacing of the dark ridges, with one side of the ridges (in this case generally on the northwest) shallower than the other, indicates that the material is windblown sand deposited in the form of dunes or large ripples.

On the slopes of and in between the dunes/ripples are smaller-scale ripples. The dark tone