People dance Tuesday, April 28, 2015, in Baltimore. Maryland's governor vowed there would be no repeat of the looting, arson and vandalism that erupted Monday in some of the city's poorest neighborhoods. (Photo by Matt Rourke/AP Photo)

A man poses with his water buffalo during “Mekepung” traditional water buffalo race on July 28, 2013 in Jembrana, Bali, Indonesia. Meaning “to chase around”, Mekepung was originally designed as a fun game for peasants to spend their free time when the harvest time was ended, as they were waiting for the start of the planting season. (Photo by Putu Sayoga)

A member of the “Exit Point” amateur rope-jumping group jumps from a 44-metre high (144-feet high) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, September 28, 2014. Fans of rope-jumping, a kind of extreme sport involving a jump from a high point using an advanced system of amortization including mountaineering and rope safety equipment, attended the Golden Autumn group's jumping season. (Photo by Ilya Naymushin/Reuters)

Labourers walk near trucks loaded with logs, which are trapped on a muddy road, near an unreserved forest in the village of Igbatoro, southwest Nigeria, August 28, 2014. Wood, a form of biomass, is the sole source of energy for hundreds of millions of Africans who lack access to modern sources of power, and logging, both legal and illegal, remains a lucrative business that has contributed to the rapid shrinking of Africa's rainforests and woodlands. (Photo by Akintunde Akinleye/Reuters)

A man dresses as a plague doctor at the Bannockburn Live event on June 28, 2014 in Stirling, Scotland. The 700th anniversary of the historic battle that saw the outnumbered Scots conquer the English led by Edward II in the First War of Scottish Independence. (Photo by Peter Macdiarmid/Getty Images)

These images of young children training were taken at a gymnastics summer camp in Bozhou, Anhui province, China on July 28, 2015. Children with promise are selected to attend, and their families hope training will not only benefit their children physically but also increase ‘willpower’, according to China News Service. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)

Brides-to-be participate in the "Running of the Brides" race in a park in Bangkok November 28, 2015. A hundred husbands and wives-to-be wore their wedding dresses and running shoes and competed in an event for a combined prize worth 1 million Thai baht ($27,928), according to the organisers. (Photo by Athit Perawongmetha/Reuters)

The second and final qualification motor (QM-2) test for the Space Launch System's booster, June 28, 2016, at Orbital ATK Propulsion Systems test facilities in Promontory, Utah. During the Space Launch System flight the boosters will provide more than 75 percent of the thrust needed to escape the gravitational pull of the Earth, the first step on NASA's Journey to Mars. (Photo by Bill Ingalls/NASA)