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Skip Brown/National Geographic/Getty Images © (Bing United States)

George Grall/National Geographic/Getty Images © (Bing United States)

Romain Cintract/hemis.fr/Getty © (Bing United States)

The Rio Grande River, Big Bend National Park, Texas -- Ian Shive/Aurora/Getty Images © (Bing United States)

Mt. Everest Base Camp -- Stefen Chow/Aurora Photos © (Bing United States)

Porcupine Northern Saskatchewan, Canada -- Wayne Lynch/All Canada Photos/Photolibrary © (Bing United States)

The Horsehead Nebula, a dark nebula in the Orion constellation. -- Stocktrek Images/Getty Images © (Bing United States)