A Sotheby's employee poses with a “Return of the Jedi” promotional C-3PO Helmet 1983, estimated at £15,000-£25,000 created by George Lucas' visual effects company during a photocall at Sotheby's in London, Britain on December 6, 2019. (Photo by Thomas Mukoya/Reuters)

Clowns pose for a picture during the International Clown Day in Guadalajara, Mexico, on December 10, 2019. (Photo by Ulises Ruiz/AFP Photo)

A reveler takes part of the Light Festival parade in San Jose, Costa Rica on December 14, 2019. (Photo by Ezequiel Becerra/AFP Photo)

Security forces' members gesture towards a woman in Santiago, Chile on December 18, 2019. (Photo by Andres Martinez Casares/Reuters)

Two young women huddle up in their coats as they brave the cold in Newcastle, England on February 1, 2019. Women in skimpy dresses and men in t-shirts enjoyed a drink and a dance as they celebrated January finally being over. (Photo by Will Walker/North News and Pictures)

A mine detection rat is given banana as a reward after successfully identifying an inactive mine on July 2, 2015 in Siem Reap, Cambodia. The Cambodian Mine Action Center (CMAC) working with the Belgian NGO APOPO has recently begun testing the feasability of using large mine detection rats from Tanzania to help clear fields of mines and unexploded ordnance in one of the most bombed and mined countries in the world. (Photo by Taylor Weidman/Getty Images)

In this photo provided by Jean Revillard, Solar Impulse 2, a plane powered by the sun's rays and piloted by Andre Borschberg, approaches Kalaeloa Airport near Honolulu, Friday, July 3, 2015. His 120-hour voyage from Nagoya, Japan broke the record for the world's longest nonstop solo flight, his team said. (Photo by Jean Revillard/Global Newsroom via AP Photo)

People make their way on an algae-covered beach in Qingdao, Shandong province, China, July 19, 2015. (Photo by Reuters/Stringer)