Probable Water Stains on Mars
http://ida.wr.usgs.gov/html/m09000/m0900047.html
http://ida.wr.usgs.gov/html/m12021/m1202154.html
http://ida.wr.usgs.gov/fullres/divided/m11039/m1103929e.jpg
http://ida.wr.usgs.gov/fullres/divided/m11042/m1104208a.jpg
http://ida.wr.usgs.gov/fullres/divided/m11035/m1103547a.jpg
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