In this picture taken Thursday, August 4, 2016, seal Tristan looks out of a basket while being released into the North Sea together with others at the beach of the island Juist, Germany. He is part of the first group of released seals of the seal breeding station Norddeich this year. (Photo by Carmen Jaspersen/DPA via AP Photo)

Women perform yoga on a dried river bank in Yunyang county, Chongqing Municipality, August 21, 2016. (Photo by Reuters/China Daily)

The supermoon rises behind Glastonbury Tor on September 27, 2015 in Glastonbury, England. Tonight's supermoon, so called because it is the closet full moon to the Earth this year, is particularly rare as it coincides with a lunar eclipse, a combination that has not happened since 1982 and won't happen again until 2033. (Photo by Matt Cardy/Getty Images)

North Korean military participate in the celebration of the 70th anniversary of the founding of the ruling Workers' Party of Korea, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on early October 11, 2015. (Photo by Reuters/KCNA)

An Iraqi special forces Counter Terrorism Service (CTS) member screams during a battle against Islamic State group jihadists (IS) in Mosul's al-Rifaq neighbourhood on January 8, 2017, as an ongoing military operation against the militants continues. Elite Iraqi forces battling the Islamic State group in eastern Mosul reached the Tigris River that splits the city in two for the first time, a spokesman said. (Photo by Dimitar Dilkoff/AFP Photo)

Smoke billows from a high-rise apartment building in west London Wednesday, June 14, 2017. A massive fire raced through the building early Wednesday, emergency officials said. (Photo by Rick Findler/PA Wire via AP Photo)

Visitors buy flowers at a flower market on the eve of Hindu goddess Durga Puja festival in Bangalore, India, 10 October 2016. The nine-day Hindu festival celebrates the killing of a demon king by the Goddess Durga representing the victory of good over evil and ends with colourful celebrations all over the country. Navratri festival runs from 03 to 11 October. (Photo by Jagadeesh N.V./EPA)

A remote-controlled plane in the form of a witch flies over a neighborhood as the sun sets during Halloween in Encinitas, California, U.S. October 31, 2016. (Photo by Mike Blake/Reuters)