This aerial photo shows the wreckage of the Asiana Flight 214 airplane after it crashed at the San Francisco International Airport in San Francisco, Saturday, July 6, 2013. (Photo by Marcio Jose Sanchez/AP Photo)
A four-month-old snow fox cub named “Vesna” (“Spring”) leaps next to a Zoo employee at the Royev Ruchey Zoo in Krasnoyarsk, Russia, on August 6, 2013. (Photo by Ilya Naymushin/Reuters)
Iranian worshippers chant slogans during a protest after their Friday prayer, as part of widespread anger across the Muslim world about a film ridiculing Islam's Prophet Muhammad on September 14, 2012. (Photo by Vahid Salemi/Associated Press)
The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)
Members of the Dominican Armed Forces participate in a commemorative act on the 170th anniversary of national independence at the esplanade of Santo Domingo, on February 27, 2014. (Photo by Orlando Barria/EPA)
An instructor (C) adjusts the posture of students of flight attendant major during a training session at Anhui Foreign Languages University, in Hefei, Anhui province, China, May 25, 2015. (Photo by Reuters/China Daily)
Andy Goldfarb, a staff biologist at the Point Defiance Zoo & Aquarium, plays with one of the four clouded leopard cubs currently at the zoo Friday, June 5, 2015 in Tacoma, Wash. The quadruplets were born on May 12, 2015 and now weigh about 1.7 lbs. each. Friday was their first official day on display for public viewing, usually during their every-four-hours bottle-feeding sessions, which were started after the cubs' mother did not show enough interest in continuing to nurse them. (AP Photo/Ted S. Warren)