The Atacama Desert is one of the driest places in the world, and the perfect location for many of astronomy’s biggest and best telescopes.
A new study added another incredible trait to this list—the desert’s Chajnantor Plateau is also the sunniest place in the world.
Researchers discovered that a meteorological phenomenon known as “forward scattering” by broken clouds periodically makes this particular plateau almost as sunny as the surface of Venus.
Few places on Earth are less hospitable than Chile’s Atacama Desert. This 1,000-mile strip of land west of the Andes is one of the driest places—second to only some areas of Antarctica that haven’t seen precipitation for millions of years.
But such an unwelcoming environment does come with a few advantages. Because of its extreme dryness, high altitude, scant cloud cover, and near-zero radio interference and light pollution, the Atacama Desert is home to some of the most advanced telescopes in the world. Which is fitting, because a new study published in June of 2023 in the Bulletin of the American Meteorological Society discovered that this land that regularly glimpses other worlds is even more... otherworldly than we knew.
It makes sense that a region as dry as the Atacama Desert would get more than its fair share of sunlight. On average, the region receives around 308 watts of shortwave irradiance (daylight) per square meter—almost twice as high as central Europe or the eastern U.S., according to The Washington Post.
But when Raul Cordero—a climatologist at University of Groningen in the Netherlands—and his team gathered solar irradiance measurements on the Chajnantor Plateau (home of the largest astronomical telescope project in the world the Atacama Large Millimeter Array), he detected periodic irradiance levels of 2,177 watts per square meter. In other worlds, Cordero stumbled upon the sunniest place on Earth.