As the International Space Station (ISS) passed over the Horn of Africa on February 19, 2020, an astronaut shot this photograph of Somalia's capital city, Mogadishu.
This historic port on the coast of the Indian Ocean is home to more than 2 million people.
Just inland from the coast, sand dunes flank the urban area. Prevailing winds from the east-northeast shape the dunes into ridges perpendicular to the wind direction.
Geologists call these "transverse dunes."
The red and orange colors in the dune fields are due to natural chemical and weathering processes that left behind traces of iron in the sandy minerals.
These dunes stand in contrast to the lightly-colored, calcium carbonate-rich sands near the shore. NASA/UPI