The Viking images were taken in October 1976, at a time when the north polar region was in the middle of summer. The MOC image was taken in August 1998, when the north polar region was in early spring. In order to catch these dunes with MOC during the same time of year that Viking saw them, a new image would have to be acquired in June 1999. The MOC team, of course, plans to try this if the ground track crosses this location in 1999. The 10 kilometer scale bar also represents about 6.2 miles.
North is up, illumination is from the lower right.
The dunes and surrounding surface appear bright because they are covered with seasonal frost left over from the northern hemisphere winter that ended in mid-July 1998. Many of the dark spots have thin, dark streaks that radiate in several different directions. The fact that these thin streaks show consistent directions from spot to spot suggest that they were caused by passing winds that mobilized some of the dark sand at each location. North is toward the upper right, illumination is from the lower left. North is toward the upper right, illumination is from the lower left.