Competitors warm up backstage during the Arnold Classic Europe bodybuilding event in Madrid, Spain, September 25, 2015. (Photo by Susana Vera/Reuters)

A dog catches a wave during the Surf City Surf Dog Contest in Huntington Beach, California September 27, 2015. (Photo by Lucy Nicholson/Reuters)

The moon rises behind the skyline and financial district in Toronto, November 25, 2015. (Photo by Mark Blinch/Reuters)

Policemen take pictures of the Soyuz TMA-17M spacecraft while it is transported from an assembling hangar to its launch pad at the Baikonur cosmodrome, Kazakhstan, July 20, 2015. The Soyuz is scheduled to blast off with Kjell Lindgren of the U.S., Kimiya Yui of Japan and Oleg Kononenko of Russia to the International Space Station on July 23, 2015. (Photo by Shamil Zhumatov/Reuters)

A humanoid robot named “Yangyang” shows a facial expression during its demonstration at the Global Mobile Internet Conference (GMIC) 2015 in Beijing, China, April 29, 20155. The android was produced jointly by China's Shanghai Yangyang Intellegent Robot Science Service center and Japanese professor Hiroshi Ishiguro, with the aim of popularising robotics among the young. (Photo by Kim Kyung-Hoon/Reuters)

Actor Cornelius Obonya as Jedermann and actress Brigitte Hobmeier as Buhlschaft perform on stage during a dress rehearsal of Hugo von Hofmannsthal's drama “Jedermann” (Everyman) at Domplatz square in Salzburg, Austria, July 16, 2015. The play is directed by Julian Crouch and Brian Mertes and will premiere as part of the annual Salzburg cultural Festival on July 19, 2015. (Photo by Leonhard Foeger/Reuters)

Edibles are displayed at Shango Cannabis shop on first day of legal recreational marijuana sales beginning at midnight in Portland, Oregon October 1, 2015. The sale of marijuana for recreational use began in Oregon on October 1, 2015 as it joined Washington state and Colorado in allowing the sale of a drug that remains illegal under U.S. federal law. (Photo by Steve Dipaola/Reuters)

Pedestrians stop to look at and photograph a DeLorean Motor Company DMC-12 customized to look identical to the car used in the film "Back to the Future Part II" and that will be part of a Lyft promotion in New York, October 21, 2015. In the 1989 movie, main character Marty McFly traveled to the future to October 21, 2015. (Photo by Lucas Jackson/Reuters)