Photo: Sand Dunes in Sossusvlei, Namibia

Taken June 28, 2009

Before anyone accuses me, I swear this is not Photoshopped and this is actually what the sand dunes looked like.  Deep in the Namib desert, the oldest desert on the planet, the sand dunes can get up to 350 meters high which makes them the tallest in the world.  The dunes are so stark that the area is said to be a popular landmark for the astronauts in fact!

The amazing thing is how when driving here the sand just shows up in clumps on the ground as if a giant’s child dropped scoops from his sand pail until the dunes dominate the horizon.  How did it get here?  Amazingly from the Atlantic Ocean over 50km away- the mighty Orange River deposits so much land that a mere tributary created the second largest canyon in the world, which is deposited on the land and picked up by the wind.  Over time, some geologists have estimated tens of millions of years, the sand is deposited here.

A final interesting detail though is how in the winter (when this picture was taken) the direction of the wind changes so it comes off the mountains located leftward in this picture, so the sand dunes shift accordingly.  See how the dunes in the distance lean towards the right?  It’s because the wind blows the sand up the straight side of the dune over the crest and then finally settles on the far side due to the wind shade, giving the dune its normal shape.  In a few months the wind will change direction and the crests will face the opposite direction, ensuring that these dunes don’t move very much over time and can get so tall.

Oh, and the dunes are orange because of iron oxide, the same reason Mars is red.  But you knew that, right?

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