The two control cabs at the Stockholm Arlanda Airport symbolize two ravens from Nordic mythology that were tasked with watching over the earth. Carolyn Russo /National Air and Space Museum, Smithsonian Institution hide caption

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The photographer brings a surreal touch to the epidemic that struck West Africa in photos titled "Le Temps Ebola." The suits worn by the people portraying health professionals evoke carnival masks and animal masks. The question the photographer ponders: "Are these figures here to protect the people or to harm them?," reflecting mistrust of medical workers in the early stages of the outbreak. Courtesy of Bakary Emmanuel Daou hide caption

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Yao Chen, Annie Leibovitz, Tavi Gevinson, Agnes Gund, and Marco Tronchetti Provera attended the launch of the 2016 Pirelli Calendar by Annie Leibovitz at Grosvenor House in London Monday. Stuart C. Wilson/Getty Images hide caption

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This 11-year-old boy lives with his family in a Roma settlement in Belgrade. "He and his brothers and sisters are without documents, but he had this amazing confidence," Constantine says. Greg Constantine hide caption

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A. Abbas/Magnum Photos

During his decades-spanning career Irving Penn photographed everything from fashion models to frozen food. Above, Ball Dress by Olivier Theyskens for Nina Ricci, New York, 2007. Conde Nast/Smithsonian American Art Museum, Gift of The Irving Penn Foundation hide caption

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On the first day of the Soviet withdrawal from Afghanistan in May 1988, an Afghan soldier hands a flag to a departing Soviet soldier in Kabul. "This was the first time journalists had full access to Kabul," Robert Nickelsberg says. It marked his first year covering Afghanistan. "It was a historical turning point for the Cold War and actually foreshadows the chaos that will descend on the country." Courtesy of Robert Nickelsberg/Getty Images hide caption

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"I struck upon this kind of crazy idea that I was going to go to New York and stop 10,000 people on the streets and take their portrait, and create kind of a photographic census of the city." Courtesy of St. Martin's Press hide caption

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Frazier's grandmother grew up in Braddock in the 1930s and '40s, when "it was prosperous and a melting pot," Frazier says. She took this photograph of her grandmother in 2002. Courtesy of artist LaToya Ruby Frazier hide caption

toggle caption Courtesy of artist LaToya Ruby Frazier