Atacama

The Atacama Desert is a desert plateau in northern Chile, along the Pacific coast from near Arica to Antofagasta. It is one of the driest places on Earth outside polar regions; some areas have not recorded measurable rainfall for decades. The aridity results from the cold Humboldt Current, the Andean rain shadow, and persistent high-pressure air.

Geography and climate: The desert covers about 105,000 square kilometers, roughly 600–1,000 kilometers long and up to 200 kilometers wide. Precipitation ranges from near zero to a few tens of millimeters annually, with hyperarid zones where rainfall is extremely rare. Nighttime temperatures are cool and daytime heat can be intense.

Landscapes and resources: It includes salt flats such as Salar de Atacama, and lunar-like valleys such as Valle de la Luna, plus geysers del Tatio. Historically the region was exploited for nitrates and, more recently, lithium, making mining a major economic activity.

People and economy: Indigenous Atacameño communities live in the region, with towns like San Pedro de Atacama. Tourism, mining, and oasis agriculture drive the economy, offering desert tours, stargazing, and cultural heritage experiences.

Astronomy: The Atacama hosts major observatories, notably ALMA on the Chajnantor Plateau and the Paranal Observatory. The region’s dry air, high altitude, and clear skies make it a leading site for infrared and submillimeter astronomy.

Ecology and science: Coastal fogs (camanchaca) sustain limited life in some areas, while inland extremophile microbes inhabit hyperarid soils. The desert is also used as a Mars analog in research and education.