A boy uses a mobile phone as he sits inside his father's snacks shop along a road in Kolkata, India, February 22, 2016. (Photo by Rupak De Chowdhuri/Reuters)

An aerial view shows the 11/19 pit and twin slag heaps at the former coal mine site in Loos-en-Gohelle, northern France, November 1, 2015. Loos-en-Gohelle, a town of 7000 inhabitants in the North of France, marked by the closure of coal mines in 1970, has demonstrated a successful transition from coal to a green economy. (Photo by Pascal Rossignol/Reuters)

Yakutsk, with a population of around 270,000, holds its own title: that of the coldest city on Earth. Here: Frost-encrusted house in the city centre. (Photo by Amos Chapple/Courtesy Images/RFE/RL)

“Red Arrows” at the 2016 royal air tattoo, RAF Fairford, UK. By Jonny Williams, finalist: action. (Photo by Jonny Williams/UK National Geographic Traveller Photography Competition 2018)

People take a selfie at the abandoned former Soviet R12 nuclear missile launch site in Zeltini, Latvia, July 22, 2016. Hidden in the forests of Aluksne, near Latvia's north-eastern border with Russia, the remains of a former Soviet nuclear missile base are a magnet for tourists now rather than a top-secret site manned by soldiers. (Photo by Ints Kalnins/Reuters)

A bomb squad member wearing heavy equipment leaves the explosion site at the Yasukuni shrine precints in Tokyo, Japan, 23 November 2015. More than 100 police, firefighters and officials gathered at the site after an explosion was heard in the toilets of the Yasukuni Shrine, a controversial war shrine in the capital Tokyo. Local media reports said police found possible traces of an explosion, as well as batteries and wires at the shrine. There were no reports of injuries. (Photo by Franck Robichon/EPA)

In this April 3, 2019, photo, horses from Nepal cavalry rest in a stable after morning practice for Ghode Jatra festival in Kathmandu, Nepal. The “Ghode Jatra” is an annual horse festival celebrated on the Nepal Cavalry grounds in Kathmandu, which marks the defeat of a Hindu demon. (Photo by Niranjan Shrestha/AP Photo)

In this September 1, 2015 photo, street artists Jenaro de Rosenzweig, left, and Alejandro Revilla pose for a portrait behind a restaurant's window covered with a mural by artist Francisco Munoz, signed with his artist's name below, in the Roma Norte neighborhood of Mexico City. Rosenzweig and Revilla founded the “Street Art Chilango” cooperative in March 2013, which is filling neighborhoods with public art by local street artists. (Photo by Rebecca Blackwell/AP Photo)