A hot air balloon floats over farm fields south of Washington, Ill., as the sun slips behind clouds on the autumn afternoon of Wednesday, September 24, 2014. (Photo by Ron Johnson/AP Photo/Peoria Journal Star)

A visitor poses with artist Joyce Pensato's artwork “Mickey for Micky” at the Frieze Art Fair in London, October 14, 2014. (Photo by Luke MacGregor/Reuters)

A woman walks past graffiti on a wall in the Williamsburg neighborhood of the borough of Brooklyn, in New York, September 16, 2014. The picture was taken through car window with raindrops. (Photo by Shannon Stapleton/Reuters)

Child models present creations at Dong Wenmei T100 Children's Collection during China Fashion Week in Beijing October 29, 2014. (Photo by Kim Kyung-Hoon/Reuters)

Singer Rihanna poses at amfAR's fifth annual Inspiration Gala in Los Angeles, California October 29, 2014. (Photo by Mario Anzuoni/Reuters)

A gallery assistant poses with the 1972 work “Secretary” at a press viewing of the artist's exhibition “Allen Jones RA” at the Royal Academy of Arts in London November 11, 2014. (Photo by Neil Hall/Reuters)

A woman photographs a Norwegian spruce Christmas tree from Oslo after it was lit at Trafalgar Square in central London, December 4, 2014. (Photo by Toby Melville/Reuters)

A performer from Cirque du Soleil's show “Quidam” practices backstage before a show at the MEO Arena in Lisbon December 18, 2014. (Photo by Rafael Marchante/Reuters)