A group of five barchan, or "horned," sand dunes can be seen in a zoomed-in version of the 2013 photo (see below). Over time, these arrowhead-shaped piles of sand are pushed across the desert by ...

In order to take aerial photos in this remote ... we found a 50-foot-tall barchan to give us some shelter for the night. We awoke before dawn. The wind on the dune crest had died down to a breeze.