David Sharp, an engineer with Lockheed Martin, displays the “Samurai Flyer”, an aviation design inspired by the maple seed, during the Association for Unmanned Vehicle Systems International Conference August 16, 2011 in Washington, DC. Lockheed Martin unveiled the new design and demonstrated vertical takeoff and landing, stable hover, and on-board video streaming of the aircraft during their demonstration. (Photo by Win McNamee/Getty Images)

Russian soldiers are pictured next to the Reichstag building in this undated photo taken May 1945 in Berlin. Some 70 years on from the Battle for Berlin, instrumental in the end of World War II, Reuters photographer Fabrizio Bensch unearthed pictures by Red Army photographer Georgiy Samsonov, showing his portrayal of a city laid siege. Bensch bought an exactly equivalent FED camera, a Soviet copy of the German-made Leica II, choosing to use black and white film to capture images of the self-same locations he detected his way to in modern-day Berlin. (Photo by Georgiy Samsonov/Reuters/MHM)

Brazilian navy soldiers watch a woman as they patrol the area at the Copacabana Beach before carnival festivities in Rio de Janeiro, Brazil February 14, 2017. (Photo by Sergio Moraes/Reuters)

Yanelis Blanco, 24, center, dances with a group of friends at Santa Maria beach, about 15 miles from Havana. It is the closest beach to Havana. Others, from left to right are Jackson Miranda, 21, Dayan Suarez, 24, and Melisa Oliva, 15. The men in the group have a rap group together. The government is demolishing buildings all over the coast of East Havana and recovering and restoring beach dunes. (Photo by Sarah L. Voisin/The Washington Post)

Parade Marshall Captain Gary Tomlin gives a command during a Remembrance Sunday parade through Fulham in West London, Britain November 8, 2009. Every year in November, villages, towns and cities across Britain honour those who have lost their lives in war on Remembrance Sunday. While Queen Elizabeth leads tributes at a national service of remembrance at The Cenotaph war memorial in central London, various neighbourhoods also hold their own local marches and memorials. (Photo by Kevin Coombs/Reuters)

Marilyn Monroe drinking a Coke and Jane Russell fixing her make-up during a break while filming “Genlemen Prefer Blondes”.

An Airbus A380 aircraft prepares to land at Mumbai airport in this May 8, 2007 file photo. Sentiment at some of Asia's biggest firms deteriorated again in the fourth quarter, falling to a four-year low under the weight of concerns about slowing growth in China, the region's biggest economy, a Thomson Reuters/INSEAD survey showed. (Photo by Arko Datta/Reuters)

A soldier walks on the bank of the river in central Pyongyang, North Korea on April 16, 2017. (Photo by Damir Sagolj/Reuters)