A Syrian man rides his bicycle past a man selling grains during a halt in fighting on February 29, 2016 in Douma, in the Eastern Ghouta region, east of the capital Damascus. A UN-backed ceasefire deal took hold across parts of Syria, bringing relative calm to areas where the Islamic State group and Al-Qaeda's local affiliate are not present. (Photo by Sameer Al-Doumy/AFP Photo)

A Rohingya migrant woman, who arrived in Indonesia by boat, carries a bottle of drinking water inside a temporary compound for refugees in Kuala Cangkoi village in Lhoksukon, Indonesia's Aceh Province May 17, 2015. (Photo by Reuters/Beawiharta)

In this Friday, March 13, 2015, Mitch Seavey's lead dogs with frosty whiskers at the Huslia, Alaska, checkpoint for the Iditarod Trail Sled Dog Race. (Photo by Loren Holmes/AP Photo/Alaska Dispatch News)

Engineer Mikhail Venin works on an antenna for the Express AM8 new generation geostationary telecommunications heavy satellite at the large-sized transformed mechanical systems centre of the Reshetnev Information Satellite Systems company in the Siberian town of Zheleznogorsk April 2, 2014. The Express AM6 is a new generation satellite providing services including Russian governmental and presidential mobile communication, digital television and broadcasting, according to the Reshetnev company representatives. (Photo by Ilya Naymushin/Reuters)

Lightning strikes near Jacobsdorf at the Oder-Spree district in eastern Germany, September 1, 2015. (Photo by Patrick Pleul/AFP Photo)

In this aerial view the officers' building and an auditorium stand at the former Soviet military base on January 26, 2017 in Wuensdorf, Germany. Wuensdorf, once called “The Forbidden City”, was the biggest base for the Soviet armed forces in communist East Germany from 1945 until the last Soviet troops left in the early 1990s following the end of the Cold War and the reunification of Germany. (Photo by Sean Gallup/Getty Images)

Men carrying a shrine jump over a bon fire, which means a wish for good luck during a traditional Chinese lunar new year celebration in Jieyang, Guangdong province, China, February 2, 2017. (Photo by Reuters/China Daily)

A man covered with mineral-rich mud smiles on a bank of lake Tus in Khakassia region, southwest of the Siberian city of Krasnoyarsk, Russia, July 16, 2016. (Photo by Ilya Naymushin/Reuters)