Children guarded by Hungarian police play on the ground after being detained along with other migrants who illegally crossed from Serbia to Hungary near the village of Asotthalom, Hungary, September 16, 2015. (Photo by Dado Ruvic/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)

Vehicles move past a man resting on a taxi, as he waits for passengers, along a road in Karachi, Pakistan, May 5, 2015. (Photo by Akhtar Soomro/Reuters)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Riot police stood by the gates of parliament in Nairobi, Kenya, Tuesday, May 14, 2013, during a demonstration against members of parliament who demanded higher wages. Demonstrators released two dozen piglets and poured blood on the pavement to protest the demands for a wage hike. (Photo by Carl de Souza/AFP Photo)

The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. The Chernobyl disaster is the worst nuclear power plant accident in history in terms of cost and resulting deaths, and is one of only two classified as a level 7 event (the maximum classification) on the International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster in 2011). Photo: Graffiti of a crying baby on a wall, Chernobyl Power Plant, Chernobyl, Ukraine. (Photo by Hans Neleman/Getty Images)

Army soldiers prepare a military elephant for the parade during a rehearsal for Sri Lanka's 68th Independence day celebrations in Colombo, February 2, 2016. (Photo by Dinuka Liyanawatte/Reuters)

Police run past a burning car as they push protesters back during the “yellow vests” demonstration near the Arc de Triomphe on December 8, 2018 in Paris France. “Yellow Vests” (“Gilet Jaunes” or “Vestes Jaunes”) is a protest movement without political affiliation which was inspired by opposition to a new fuel tax. (Photo by Chris McGrath/Getty Images)