A woman walks up the steps decorated ahead of the Chinese New Year festival in Beijing, China, Thursday, January 12, 2017. The Chinese Lunar New Year is the most important holiday for Chinese and hundreds of millions are expected to return to their hometown to spend the new year with their family and relatives. (Photo by Ng Han Guan/AP Photo)

A six-year-old acrobat performs on the opening of a tourist festival in Bozhou, Anhui province, China May 3, 2015. (Photo by Reuters/China Daily)

Boys walk home for lunch from school in the village of Kogelo, west of Kenya's capital Nairobi, July 16, 2015. U.S. President Barack Obama visits Kenya and Ethiopia later this month. His ancestral home of Kogelo is home to Sarah Hussein Obama, his step-grandmother. The Kenyan village, burial place of Obama's father, features an open-pit goldmine, a pork butcher's, a school named after their most famous son and outdoor market stalls. Villagers get around by motorbike taxi or on foot while a donkey-cart transports water. Children, some of them named Obama in honour of the President, walk to and from school together. (Photo by Thomas Mukoya/Reuters)

Employees prepare spacesuits at the Russian-leased Baikonur cosmodrome in Kazakhstan on August 19, 2015. Members of the main crew of the 45/46 expedition to the International Space Station ISS, Kazakhstan's cosmonaut Aydyn Aimbetov, Russian cosmonaut Sergei Volkov and Denmark's astronaut Andreas Mogensen from the European Space Agency, are scheduled to blast off to the International Space Station (ISS) on September 2, 2015. (Photo by AFP Photo)

This August 28, 2017 photo shows eight-year-old Indian girl Bharti performing a balancing act on a rope during a street show in Batala, India. Travelling Indian performers, who earn a meagre income from putting on shows on the streets, often scout areas to gather a large street audience who then give money on a collection plate at the end of the show. (Photo by Narinder Nanu/AFP Photo)

Fire over Vieira de Leiria, Portugal, on October 16, 2017 as a series of deadly wildfires broke out across Spain and Portugal as the approach of Hurricane Ophelia whipped up strong winds that fanned the flames. (Photo by Helio Madeiras/News Pictures)

A dead whale is seen on the shore of the Ipanema beach in Rio de Janeiro, Brazil November 15, 2017. A biologist, Rafael Carvalho, said on Wednesday the whale appeared to have been dead for a few days. Authorities were urging beachgoers who had flocked to Ipanema on a national holiday to stay away from the animal. However, many were spotted near the carcass with some people playing in the water nearby. The whale is approximately 39 feet (12 metres) long and weighs about 25 tonnes. (Photo by Pilar Olivares/Reuters)

Tourists ride a cable car in the form a of a Chiva, a bus used to serve rural routes, in Pitalito, Colombia, Tuesday, April 5, 2017. The ride called “La Chiva Voladora” costs about $0.70 and you zip along about 800 meters from one side of a hill to another. (Photo by Fernando Vergara/AP Photo)