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)

Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

A driver on the Horseshoe Pass in North Wales wiping the snow from the windscreen of his car during a heavy snow storm, 18th January 1937. (Photo by Norman Smith)

Aerial photo taken on April 20, 2018 shows the view of advection fog above Qingdao, a coastal city in east China' s Shandong Province. (Photo by Lu Hui/Xinhua News Agency/Eyevine)

France fan before the Russia 2018 World Cup Group C football match between Denmark and France at the Luzhniki Stadium in Moscow on June 26, 2018. (Photo by Axel Schmidt/Reuters)

A bull savar (jockey) guides his bulls as he competes in a bull race on the outskirts of Islamabad, Pakistan July 1, 2018. (Photo by Faisal Mahmood/Reuters)

Six new Canadians take their oath of citizenship while harnessed on the CN Tower's “Edgewalk” 356 metres (1,168 feet) above Toronto, Ontario, Canada in a still image from video October 9, 2018. (Photo by CN Tower/Handout via Reuters)

Novice DSLR (Digital single-lens reflex camera), 2nd Place. “Smile of a Friend”, American Crocodile (Crocodylus acutus) in Jucaro, Cuba. (Photo by Antonio Pastrana/The Ocean Art 2018 Underwater Photography Competition)