The Northern Lights glow green in a spectacular light show above a field of trees frozen solid with snow. (Photo by Jaak Sarv/Solent News & Photo Agency)

A fan lies passed out on the first day of the Wacken Open Air heavy metal music fest on August 4, 2011 in Wacken, Germany. Approximately 75,000 heavy metal fans from all over the world have descended on the north German village of 1,800 residents for the annual three-day fest. (Photo by Sean Gallup/Getty Images)

Members of the Prizma Ensemble wearing full solid-coloured bodysuits take part in a festival for the Jewish holiday of Hanukkah, in Jerusalem December 26, 2016. (Photo by Amir Cohen/Reuters)

Members of the Prizma Ensemble wearing full solid-coloured bodysuits walk pest ultra orthodox jewish men as they take part in the 6th Jane's walk Jerusalem in Jerusalem, Israel May 6, 2016. Jane's Walk is a global walking tour movement, inspired by US-Canadian author and activist Jane Jacobs. (Photo by Baz Ratner/Reuters)

A staff member at the Rising Sun Anger Release Bar suits up in protective gear August 8, 2006 in Nanjing of Jiangsu Province, China. (Photo by China Photos/Getty Images)

These Arab recruits line up in a barracks square in the British Mandate of Palestine, on December 28, 1940, for their first drill under a British solider. Some 6,000 Palestinian Arabs signed up with the British Army during the course of World War II. (AP Photo)

A festival goer cools down with fresh water while taking part in the Hellfest metal music festival on June 17, 2022 in Clisson, western France. (Photo by Loic Venance/AFP Photo)

World medieval jousting champion Rod Walker poses before next month’s St Ives Medieval Faire, the only solid wood lance joust tournament in the southern hemisphere in Sydney, Australia on August 26, 2016. (Photo by Dan Himbrechts/AAP)