In this April 14, 2014 file photo, Hamamatou Harouna, 10, who lost the use of her legs to polio, crawls to the restroom on the grounds of the Catholic Church where she and hundreds of others found refuge after fleeing violence in her village, in Carnot, Central African Republic. Health authorities on Tuesday, August 25, 2020 are expected to declare the African continent free of the wild poliovirus after decades of effort, though cases of vaccine-derived polio are still sparking outbreaks of the paralyzing disease in more than a dozen countries. (Photo by Jerome Delay/AP Photo/File)

People pose for photos in the snow in the Manhattan borough of New York City, New York, U.S., December 2, 2019. (Photo by Carlo Allegri/Reuters)

Medical staff members wearing protective clothing to help stop the spread of a deadly virus which began in the city, arrive with a patient at the Wuhan Red Cross Hospital in Wuhan on January 25, 2020. The Chinese army deployed medical specialists on January 25 to the epicentre of a spiralling viral outbreak that has killed 41 people and spread around the world, as millions spent their normally festive Lunar New Year holiday under lockdown. (Photo by Hector Retamal/AFP Photo)

Milena Jami whips her llama to win the first place in the a race for children of ages seven and eight at the Llanganates National Park, Ecuador, Saturday, February 8, 2020. Wooly llamas, an animal emblematic of the Andean mountains in South America, become the star for a day each year when Ecuadoreans dress up their prized animals for children to ride them in 500-meter races. (Photo by Dolores Ochoa/AP Photo)

A brilliant sunset makes for a fun silhouette picture by jumping between sand bars at Shi Shi Beach on the Olympic Peninsula Friday July 17, 2015. (Photo by Bettina Hansen/The Seattle Times)

A man photographs the main engines of the space shuttle orbiter Discovery on display at the Udvar-Hazy Smithsonian National Air and Space Annex Museum in Chantilly, Virginia August 28, 2015. Shuttle Discovery had 27 years of service and flew 39 times before being retired in 2011. (Photo by Gary Cameron/Reuters)

“Aurora over a glacier lagoon”. A vivid green overheaded aurrora pictured in Iceland's Vatnajokull National Park reflected almost symetrically in Jokulsrlon Glacier lagoon. A complete lack of wind and currrent combin in this sheltred lagoon scene to crete an arresting mirror effect giving the image a sensation of utter stillness. Despite theis there is motion on a suprising scale, as the loops and arcs of the aurora are shaped by the shifting forces of the Earth's magnetic field. James Woodend of Great Britain won the grand prize with the image, beating out more than 2,500 other entries. The Astronomy Photographer of the Year 2014 contest is judged by the Royal Observatory Greenwich and BBC Sky at Night magazine. (Photo by James Woodend/The Astronomy Photographer of the Year 2014 Contest)

“Sunward”. When the Mediterrenean Mantis opened its wings, It seemed very impressive at the sunshine... Photo location: Nicosia, Cyprus. (Photo and caption by Hasan Baglar/National Geographic Photo Contest)