Northern lights (Aurora borealis) glow brightly over an Inupiaq fish camp along the arctic coast in North Slope, Alaska. (Photo by Steven Kazlowski/Barcroft Media)

Soldiers take part in a drill during a heavy snow in Heihe, Heilongjiang province, February 26, 2014. (Photo by Reuters/China Daily)

A picture taken on July 14, 2014 from a Boeing C135 refueling tanker shows two French Rafale fighter planes, flying over the French capital during the annual Bastille Day military parade on the Champs-Elysees in Paris. France has issued an unprecedented invitation to all 72 countries involved in World War I to take part in its annual Bastille Day military parade. (Photo by Franck Pennant/AFP Photo)

A cadet lies on the grass after collapsing during a promotion ceremony at a police school in Bogota December 7, 2012. (Photo by John Vizcaino/Reuters)

Model Bar Refaeli arrives at amfAR's Cinema Against AIDS 2007 at Le Moulin de Mougins on May 23, 2007 in Mougins, France. The amfAR Foundation raises funds for research, education and treatment of AIDS/HIV worldwide.

A horse-drawn cart passing through a section cut out of the base of a giant sequoia tree in the Mariposa groves of Yosemite Park, California. (Photo by Carleton E Watkins/Getty Images). 1870

A Chinese girl touches the gun of a relievo featuring Chinese soldiers fighting with Japanese troops during World War II at an exhibition at the Anti-Japan War Museum to mark the 60th Anniversary of the Victory of the Chinese People's War of Resistance Against Japan on August 18, 2005 in Beijing, China. (Photo by Cancan Chu/Getty Images)

A picture taken on October 17, 2017 shows Madame Tussauds museum's wax figure of US President displayed along the East Side Gallery section of the Wall in Berlin during a photo session. The wax figure will be displayed at Madame Tussauds museum in Berlin from October 20, 2017. (Photo by Jens Kalaene/AFP Photo/DPA)