Photo of the Day

Picture of the Petito Moreno glacier in Argentina

Gargantuan Glacier

Argentina's Perito Moreno Glacier spans almost 100 square miles, and stands 200 feet above Lake Argentino. Scientists believe the glacier, one of dozens of ice fields in Patagonia's Los Glaciares National Park, is 18,000 years old.
Photograph by Peter Essick, Nat Geo Image Collection