This photo taken on December 2, 2015 shows a lenticular cloud forming as white streaks from airplanes mark the blue sky, in a rare atmospheric phenomena above the town of Gevgelija on December 2, 2015. Lenticular clouds have been regularly confused for UFOs throughout history due to the their smooth, round or oval lens-shaped structure. (Photo by Armend Nimani/AFP Photo)

Cara Delevingne and Kate Moss attend the Burberry Prorsum show during London Fashion Week Spring Summer 2015 on September 15, 2014 in London, England. (Photo by Anthony Harvey/Getty Images)

Rihanna attends the Balmain show as part of the Paris Fashion Week Womenswear Fall/Winter 2014-2015 on February 27, 2014 in Paris, France. (Photo by Dennis Leupold/The Guardian)

A man dressed as Ironman takes a seat in the cafeteria on the second day of the London Super Comic Convention at the ExCel centre in east London, on March 15, 2015. (Photo by Justin Tallis/AFP Photo)

The shadow of a partial eclipse is cast on to the cheek of a student on the roof of the Jana Dlugosza Academy in Czestochowa, Poland March 20, 2015. (Photo by Grzegorz Skowronek/Reuters/Agencja Gazeta)

Model Juliana Paesthe (C) of Viradouro samba school participates in the annual carnival parade in Rio de Janeiro's Sambadrome, February 15, 2015. (Photo by Ricardo Moraes/Reuters)

Carnival revellers carry burning wooden sticks during the traditional Swiss Chienbaese celebration in Liestal near Basel February 22, 2015. (Photo by Ruben Sprich/Reuters)

People with his face covered in oil and soot and carrying bull horns representing a devil join a carnival festival on February 14, 2015 in Luzon, Spain. (Photo by David Ramos/Getty Images)