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)

Relatives and friends react during the funeral of Bryan Sandoval, 17, a victim of a landslide that has left at least 112 dead and 350 missing people, in El Cambray II village, Santa Catarina Pinula, Guatemala, 04 October 2015. The landslide took place on 01 October 2015 when heavy rains saturated the soil. (Photo by Esteban Biba/EPA)

View of a raccoon dog or Tanuki (Nyctereutes procyonoides) at the Chapultpec Zoo in Mexico City on August 06, 2015. This species is native from Japan and China. (Photo by Alfredo Estrella/AFP Photo)

A young Afghan vendor waits for customers to buy sheep's heads at a roadside stall at the busy market in Kabul on November 29, 2015. (Photo by Wakil Kohsar/AFP Photo)

A light installation is seen on the facade on the banks of the Saone river to pay tribute to the victims of the Paris attacks in Lyon, France, December 8, 2015. (Photo by Robert Pratta/Reuters)

Policewomen take a picture inside a tunnel under the Chao Phraya river at a Mass Rapid Transit subway station in Bangkok, Thailand, December 14, 2015. (Photo by Athit Perawongmetha/Reuters)

Members of the ice swimming club “Berliner Seehunde” (Berlin Seals) take a dip in the Orankesee lake as part of their traditional Christmas swimming session in Berlin, Germany, December 25, 2015. (Photo by Hannibal Hanschke/Reuters)

Internally displaced Syrian children stand at the entrance of their makeshift shelter that is an underground cave in Om al-Seer, southern Idlib countryside, Syria December 26, 2015. (Photo by Khalil Ashawi/Reuters)