Hemispheric color differences on Saturn's moon Rhea are apparent in this false-color view from NASA's Cassini spacecraft in this March 2, 2010 file photo. (Photo by Reuters/NASA/JPL/SSI)

This photo taken on October 8, 2017 shows dancers posing in formation to celebrate the upcoming Party Congress, in Rongan in China' s southern Guangxi region. China will convene its 19 th Party Congress on October 18, state media said, a key meeting held every five years where President Xi Jinping is expected to receive a second term as the ruling Communist Party' s top leader. (Photo by AFP Photo/Stringer)

A visitor poses for a picture during Sao Paulo Fashion Week in Sao Paulo, Brazil, March 16, 2017. (Photo by Nacho Doce/Reuters)

Miss Universe contestant Desire Cordero, of Spain, poses for a photo after a news conference for contestants from Latin America and Spain, Monday, January 12, 2015, in Doral, Fla. The Miss Universe pageant will be held on January 25, in Miami. (Photo by Wilfredo Lee/AP Photo)

Visitors walk past vintage and classic cars displayed by Bonhams auction house, during an exhibition, at the Grand Palais in Paris, Wednesday, February 4, 2015. The Grand Palais is staging an exhibition of vintage cars, to be followed by a sale of historic cars by Bonhams auction house on Thursday. (Photo by Jacques Brinon/AP Photo)

A robot Ecce by the Robot studio is pictured at the world's largest industrial technology fair, the Hannover Messe, in Hanover April 13, 2015. (Photo by Wolfgang Rattay/Reuters)

People are reflected in mirrors as they walk in a busy shopping district in Tokyo, Japan, December 25, 2015. (Photo by Thomas Peter/Reuters)

Second place, Nature: double trapping. Picture taken in the Brazilian Pantanal ... when I downloaded the CF did not want to believe it ... The nature knows we always give magnificent events but sometimes extraordinary. (Photo by Massimiliano Bencivenni/National Geographic Travel Photographer of the Year Contest)