Two carnival revellers masquerade as Leonardo da Vinci's painting “Mona Lisa” pose in St. Mark's Square in Venice, Italy, Sunday, January 31, 2016. Carnival-goers in Venice are being asked by police to momentarily lift their masks as part of new anti-terrorism measures for the annual festivities. (Photo by Domenico Stinellis/AP Photo)

In this photo taken Tuesday, February 2, 2016, asylum seekers gather round a fire as they cook a meal overlooking the temporary Altnes camp refugee camp on the island of Seiland, northern Norway. Waiting for their asylum claims to be processed, hundreds of people in emergency shelters in Hammerfest and neighboring towns are slowly getting used to the extreme climate and unfamiliar customs of the High North. They say they have adapted to the cold – the temperature rarely drops below minus 10 degrees C (14 F) along the coast, though it gets much colder further inland. It’s the darkness that throws them off. (Photo by Alastair Grant/AP Photo)

In this photo taken with long time exposure, a woman wears a hat at Churchill Downs before the 145th running of the Kentucky Derby horse race Saturday, May 4, 2019, in Louisville, Ky. (Photo by Charlie Riedel/AP Photo)

A solders in ceremonial attire sweats as he waits outside Suddhaisavarya Prasad Hall, in which Thailand's King Maha Vajiralongkorn scheduled to grant a public audience in Bangkok, Thailand, Monday, May 6, 2019. King Maha Vajiralongkorn was officially crowned amid the splendour of the country's Grand Palace, taking the central role in an elaborate centuries-old royal ceremony that was last held almost seven decades ago. (Photo by Gemunu Amarasinghe/AP Photo)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

In this Monday, September 22, 2014 photo provided by the Utah Division of Wildlife Resources, a young cougar is released back into Utah's mountains by the Utah Division of Wildlife Resources in an undisclosed site in central Utah. State wildlife officials received reports of the cougar roaming Sunday afternoon in a residential area of the city's eastern flank, a few miles from the base of the Wasatch Mountains. Authorities say cougars generally avoid humans but sometimes enter neighborhoods close to their mountain habitats. (Photo by Steve Gray/AP Photo/Utah Division of Wildlife Resources)

A Felix the Cat balloon and other parade floats and balloons are led down Broadway during the annual Macy's Thanksgiving Day Parade; ca. 1900s, Broadway, Manhattan, New York City, New York State, USA. (Photo by Underwood & Underwood/Corbis)

A participant blows on yellow powder held in her hand during a Holi Party before the Gay Pride Parade in Barcelona on July 9, 2016. (Photo by Lluis Gene/AFP Photo)