A girl salutes to visitors before a show at the Mangyongdae Children's Palace in central Pyongyang, North Korea May 5, 2016. Pyongyang held a gala of song and dance performances by local school children on May 5 for visiting delegations of foreign journalists and tourists at the Mangyongdae Children's Palace. The event included orchestral, choir, and acrobatic performances, many of them with political undertones. The Seventh Worker's Party Congress commences on May 6, 2016. (Photo by Damir Sagolj/Reuters)

A bride from the Santa Marta slum takes a break after getting her makeup done before a group wedding in Rio de Janeiro December 17, 2014. A total of 16 couples took part in a mass wedding ceremony organized by the Police Peacekeeping Unit (UPP) as part of activities geared towards social enhancement of the slums. (Photo by Pilar Olivares/Reuters)

People in traditional dance before competing in the 53rd Verdiales music contest in Malaga, southern Spain December 28, 2014. Verdiales is a form of traditional Flamenco music, which is common in the province of Malaga. Members of singing groups, known as “pandas”, wear traditional costumes decked with flowers and other accessories as they perform in the contest, which is held annually on December 28. (Photo by Jon Nazca/Reuters)

In this October 15, 2014 file photo, Katsu Nakamura, sky division manager for Yamaha USA, moves the RMax unmanned helicopter into position before a demonstration of its aerial application capabilities at the University of California, Davis' Oakville Station test vineyard in Oakville, Calif. Researchers at UC Davis have been studying the effectiveness of the drone's ability for spraying pest control and nutritional materials on the test vineyard in California's Napa Valley. (Photo by Rich Pedroncelli/AP Photo)

This is the remarkable moment a group of skydivers performed a world record breaking feat in honour of their friend who died while skydiving. Known as a “Bigway”, the daring jump involves 57 people holding hands in a predetermined design as they hurtle towards the ground, head first. After making the first shape, the group then break away before coming back together to form a second shape all in a single skydive. Captured using a GoPro camera by Alaskan skydiver, Ben Nelson, 36, the topsy-turvy footage shows the adrenalin junkies soaring through the air at around 160mph before banding together twice in mid-air, making the stunt a world first. (Photo by Ben Nelson/Caters News)

A Uyghur boy sits atop a horse as he has his picture taken outside the Id Kah Mosque before the Eid holiday on July 28, 2014 in old Kashgar, Xinjiang Province, China. Nearly 100 people have been killed in unrest in the restive Xinjiang Province in the last week in what authorities say is terrorism but advocacy groups claim is a result of a government crackdown to silence opposition to its policies. China's Muslim Uyghur ethnic group faces cultural and religious restrictions by the Chinese government. Beijing says it is investing heavily in the Xinjiang region but Uyghurs are increasingly dissatisfied with the influx of Han Chinese and uneven economic development. (Photo by Kevin Frayer/Getty Images)

“Freedom”. After the 30 years banning import large motorcycle, in 2007, the Taiwan government reopened the import licensing of the motorcycle displacement over 550 cubic centimeter. Those large bikes, which were never seen before, were strange thought and treated unequally frequently. However, those adversity will not stop those enthusiastic bike riders from chasing the road of freedom. Photo location: Taiwan. (Photo and caption by 火花 羅/National Geographic Photo Contest)

Dancers prepare before a performance in the backstage area of the Buick exhibition during the “Auto China 2014” Beijing International Automotive Exhibition in Beijing on April 21, 2014. Leading automakers have gathered in Beijing for the kickoff of China's biggest car show, but lackluster growth and environmental restrictions in the world's largest car market have thrown uncertainty into the mix. (Photo by AFP Photo)