While orbiting over South America” on March 17, 2019, an astronaut aboard the International Space Station (ISS) shot this photograph of the Atacama Desert, the driest non-polar desert in the world, and the numerous salt flats in the Andes Mountains along the border of Chile and Bolivia. The centerpiece is the Salar de Uyuni, the largest salt flat on Earth.
Salar de Uyuni regularly captures the attention of astronauts due to its high contrast against the brown landscape, according to NASA.
Salar de Uyuni
At 10,582 square kilometers (4,086 sq mi), Salar de Uyuni is the world’s largest salt flat. It has an elevation of 3,656 meters (11,995 feet) above sea level (Salar means salt flat in Spanish).
Because of its location, large area, and flatness, it is a major car transport route across the Bolivian Altiplano, except when seasonally covered with water.
The area has a relatively stable average temperature with a peak at 21 °C (69.8 °F) in November to January and a low of 13 °C (55.4 °F) in June. The nights are cold all through the year, with temperatures between -9 °C (15.8 °F) and 5 °C (41 °F).
Some 30,000 to 42,000 years ago, the area was part of a giant prehistoric lake, Lake Minchin, which was named after Juan B. Minchin, the Bolivian geologist and engineer of the 19th-century. This lake later transformed into Paleo-Lake Tauca having a maximal depth of 140 meters (460 ft).
The youngest prehistoric lake was Coipasa, which was radiocarbon dated to 11,500 to 13,400 years ago. When it dried, it left behind two modern lakes, Poopó and Uru Uru, and two major salt deserts, Salar de Coipasa and the larger Salar de Uyuni.
Salar de Uyuni on Wikipedia “Salt Flats, Mountains, and Moisture” on NASA Earth Observatory webpage