A man walks through the morning mist in a park in Rozzano, near Milan, northern Italy, Thursday, December 17, 2015. (Photo by Antonio Calanni/AP Photo)

In this November 20, 2017 photo, Indian kushti wrestlers fight in the ring, during their daily training at an akhada, a kind of wrestling hostel at Sabzi Mandi, in New Delhi, India. Like many traditions in rapidly modernizing India, kushti wrestling faces the threat of being left behind. But for many poor families, the ancient sport provides a glimmer of hope. (Photo by Dar Yasin/AP Photo)

In this May 2016 photo released by The Ocean Agency/XL Catlin Seaview Survey, a boat sails near a coral reef that has been bleached white by heat stress in the Maldives. oral reefs, unique underwater ecosystems that sustain a quarter of the world's marine species and half a billion people, are dying on an unprecedented scale. Scientists are racing to prevent a complete wipeout within decades. (Photo by The Ocean Agency/XL Catlin Seaview Survey via AP Photo)

A woman stands on the footbridge over the river Garry near Pitlochry, Scotland, Britain on October 10, 2018. (Photo by Russell Cheyne/Reuters)

Men eat oranges from a push cart along a road as a vehicle travels past them in Karachi January 22, 2015. (Photo by Akhtar Soomro/Reuters)

“Krampus is a beast-like creature from the folklore of Alpine countries thought to punish children during the Yule season who had misbehaved, in contrast with Saint Nicholas, who rewards well-behaved ones with gifts. Krampus is said to capture particularly naughty children in his sack and carry them away to his lair”. – Wikipedia. Photo: A participant dressed as the Krampus creature pulls a barrel of fire past onlookers during his search for delinquent children in Neustift im Stubaital. (Photo by Sean Gallup)

“A small British company with a dream of building a re-usable space plane has won an important endorsement from the European Space Agency (ESA) after completing key tests on its novel engine technology. Reaction Engines Ltd believes its Sabre engine, which would operate like a jet engine in the atmosphere and a rocket in space, could displace rockets for space access and transform air travel by bringing any destination on Earth to no more than four hours away”. – Chris Wickham via Reuters. Photo: Artist's impression of Skylon. (Photo by Reaction Engines Ltd)

A general view of Edinburgh Castle on February 7, 2012 in Edinburgh, Scotland. The castle dominates the city skyline was built on top of an extinct volcano, and has had a human settlement on the castle site since 900BC. (Photo by Jeff J. Mitchell/Getty Images)