A girl uses her mobile phone during the evening at the National Park in Khartoum, Sudan, April 24, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

Revellers ride during the 54th annual brass band festival in the Serbian village of Guca August 7, 2014. Every year Guca is swamped by thousands of people taking part in the celebration of brass band music. (Photo by Marko Djurica/Reuters)

Early morning shark Sean McKeon pictured during severe flooding Oliver Plunkett street, Cork city, on February 3, 2014. (Photo by Daragh McSweeney/Provision)

Afghan air force 2nd Lt. Niloofar Rhmani walks the flight line at Shindand Air Base, Afghanistan, prior to her graduation from undergraduate pilot training, on May 13, 2013. Rhmani made history on May 14, when she became the first female to successfully complete undergraduate pilot training and earn the status of pilot in more than 30 years. She will continue her service as she joins the Kabul Air Wing as a Cessna 208 pilot. (Photo by Senior Airman Scott Saldukas/USAF)

U.S. Army helicopters providing support for U.S. ground troops fly into a staging area fifty miles northeast of Saigon, Vietnam, August 28, 1966. Helicopter fuel is stored in the large rubber tanks, foreground. (Photo by Henri Huet/AP Photo)

A person viewing the Northern lights over the lava landscape, Reykjanes Peninsula, Iceland. (Photo by Arctic-Images/Getty Images)

Photo taken on January 3, 2018 shows the snow-light show at the Sun Island International Snow Sculpture Art Expo in Harbin, capital of northeast China's Heilongjiang Province. Snow Wonderland, a 3D snow-light show applying modern sound, light and digital technologies has been displayed at Sun Island International Snow Sculpture Art Expo recent days. (Photo by Wang Jianwei/Xinhua via Getty Images)

Hindu devotees (not pictured) touch a child with their feet as part of a ritual to bless him during a religious procession held to mark the Gajan festival in Kolkata, India, April 13, 2018. (Photo by Rupak De Chowdhuri/Reuters)