Swimmers in fancy costume take part in the New Year's Day swim at Saundersfoot in Wales, Britain, January 1, 2017. (Photo by Rebecca Naden/Reuters)

Jason Garcia poses as The Joker from Batman at the 2015 Comic-Con International in San Diego, California, July 9, 2015. (Photo by Sandy Huffaker/Reuters)

Competitors perform at the World Irish Dance Championship on April 13, 2014 in London, England. The 44th World Irish Dance Championship is currently running at London's Hilton London Metropole hotel, and will host approximately 5,000 dancers competing in solo, Ceili, modern figure choreography and dance drama categories during the week long event. (Photo by Dan Kitwood/Getty Images)

This photo provided by NASA shows a full moon rising behind the United Launch Alliance Atlas V rocket with NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft onboard at the Cape Canaveral Air Force Station Space Launch Complex 41, Sunday, November 17, 2013, Cape Canaveral, Florida. NASA's next Mars-bound spacecraft, the Mars Atmosphere and Volatile Evolution, or MAVEN, is the first spacecraft devoted to exploring and understanding the Martian upper atmosphere. (Photo by Bill Ingalls/AP Photo/NASA)

In this June 17, 2014 photo, a North Korean man takes shelter in the rain next to long propaganda billboards in the town of Samjiyon in North Korea's Ryanggang province. The Associated Press was granted to embark on a weeklong road trip across North Korea to the country’s spiritual summit Mount Paektu. The trip was on North Korea's terms. An AP reporter and photographer couldn't interview ordinary people or wander off course, and government “minders” accompanied them the entire way. (Photo by David Guttenfelder/AP Photo)

A woman holding an umbrella walks past the sculpture by Chinese artist Yue Minjun beside a road during a snow in Beijing, China, November 22, 2015. (Photo by Jason Lee/Reuters)

A production department of a textile factory is seen abandoned in Kaduna, Nigeria November 3, 2016. President Muhammadu Buhari hopes to revive the once flourishing textile and leather industries in northern Nigeria to end the country's dependence on oil exports and diversify Africa's biggest economy. (Photo by Afolabi Sotunde/Reuters)

Racegoers in fashionable hats attend Ladies Day at Cheltenham Festival on March 15, 2017 in Cheltenham, England. (Photo by David Davies/PA Wire)