U.S. Marines, left, and South Korean Marines, wearing blue headbands on their helmets, take positions after landing on the beach during the joint military combined amphibious exercise, called Ssangyong, part of the Key Resolve and Foal Eagle military exercises, in Pohang, South Korea, Saturday, March 12, 2016. North Korea said Saturday its military is ready to pre-emptively attack and “liberate” the South in its latest outburst against the annual joint military drills by the United States and South Korea. (Photo by Kim Jun-bum/Yonhap via AP Photo)

A military guard carries flowers through the Cementerio Santa Ifigenia where the remains of former Cuban President Fidel Castro were entombed December 4, 2016 in Santiago de Cuba, Cuba. The tomb stands to the side of a memorial to the rebel soldiers killed in an attack that Castro led on Santiago's Moncada barracks on July 26, 1953, and in front of the mausoleum of Cuban national hero Jose Marti. (Photo by Chip Somodevilla/Getty Images)

Bronze whaler shark (Carcharhinus brachyurus), caught in traditional seine net and released by fisherman, Muizenberg beach, Cape Town, South Africa on October 11, 2016. Action shots have captured fishermen trying to free a potentially deadly Bronze Whaler shark who was caught in their nets. The incredible images show the eight-foot-long 500-pound predator lunging its mouth towards the fishermen who are desperately trying to pull it back into the safety of the sea by its tail. Eventually they succeeded. (Photo by Chris and Monique Fallows/NPL)

Breath of an Arctic fox by Marco Gaiotti, Italy. Marco was watching this little Arctic fox as it incessantly called another nearby. Gradually he noticed the fox’s wet breath was quickly freezing in the air after each call. It was late winter in Spitsbergen, Svalbard, and the air was -35C (-31F). Photographing Arctic foxes is often frustrating, as they are normally running around fast in search of food, but this one was very relaxed and let Marco get close enough to focus on it, with the light glowing perfectly in the background. (Photo by Marco Gaiotti/Wildlife Photographer of the Year 2021)

Passengers prepare to take part in the No Pants Subway Ride in Prague, Czech Republic, Sunday, January 8, 2017. The No Pants Subway Ride began in 2002 in New York as a stunt and has taken place in cities around the world since then. (Photo by Petr David Josek/AP Photo)

A Poison Ivy and Boba Fet (Star Wars) cosplayer during the MCM Birmingham Comic Con at NEC Arena on March 18, 2017 in Birmingham, England. (Photo by Ollie Millington/Getty Images)

A Balinese Hindu blows fire, during a parade carrying Ogoh-ogoh effigies symbolising evil spirits, during a ritual before Nyepi, the day of silence, in Palembang, South Sumatra province, Indonesia March 8, 2016. Nyepi is a day of silence for self-reflection celebrating the Balinese Hindu new year, where people may not use lights, light fires, work, travel nor enjoy entertainment. (Photo by Darren Whiteside/Reuters)

Fans cheer in the stands ahead of the CFL's 102nd Grey Cup football championship between the Calgary Stampeders and the Hamilton Tiger Cats in Vancouver, British Columbia, November 30, 2014. (Photo by Todd Korol/Reuters)