English: Australia’s Simpson Desert has been called “the ultimate social distance”—a sprawling region of dunes and sand transected by only by a few four-wheel drive tracks. This remote location in central Australia is the perfect place to get away from people—if you can survive the heat and lack of water.

The Simpson Desert stretches over roughly 143,000 square kilometers (55,000 square miles) of the southeastern corner of the Northern Territory, southeastern Queensland, and northern South Australia. The Earth’s longest parallel sand dunes run diagonally through part of the desert. Oriented northwest to southeast, they were sculpted by prevailing winds from the southeast over eons. Many are stabilized by roots of drought-resistant plants that survive in the dry, hot sand. Dunes rise between 10-40 meters (33-130 feet) and extend from one to several hundred kilometers (one-half to hundreds of miles) long. Estimation of the age of the dunes by isotope dating shows the dunefield formed in the Early Pleistocene era, roughly 1 million years ago.

The primary colors of the Simpson Desert range from orange-red to yellowish-tan. In the yellow-toned southeast, sand is fine to medium grain and contains abundant zircon, ilmenite, and garnet with minor amounts of iron oxides. These and other physical characteristics suggest that the sand in this area was derived from floodplains of rivers and salt lake systems. In contrast, the red tones found in the north and western regions come from medium-grained sands rich in iron oxides and kaolinite, suggesting that these grains came from weathering and erosion of sediments lying deep underneath the surface. Studies of sand in the Simpson Desert also show that sand has been frequently washed into some areas by waters flowing in ancient rivers and spilling across the desert.

The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite acquired a true-color image of the Simpson Desert on January 31, 2021. The color transition from rusty-red to tan-tinted-gold paints a stunning portrait of a summer day in the Simpson. The parallel lines of the tall dunes can most easily be seen in the south and east.