Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, February 10, 2016. (Photo by B.K. Bangash/AP Photo)

Non-Hindus carry nets as they wait on the edge of the crater to catch offerings cast down by Hindus during the Kasodo ceremony at Mount Bromo, Probolinggo, Indonesia, August 12, 2014. The Kasodo ceremony is a way of Tengger Hindus to express their gratitude to God for good harvest and fortune. The offerings range from vegetables to chickens, from fruits to goats, from money to other valuables. (Photo by Fully Handoko/EPA)

The Y-40 Deep Joy is the worlds deepest pool. Y-40 is projected by Architect Emanuele Boaretto and supported by the “Boaretto Group Hotel and Resort”. The name Y-40 is inspired by mathematical symbols. “Y” is the ordinate axis of the Cartesian system and “–40” means the world's record depth or our pool- that is 40 meters underground. (Photo by Courtesy Y40 Deep Joy)

A Manipuri woman sells smoked and dry fish in Ima market - the world's largest all women market – in Imphal city, Manipur state, 06 January 2016. The 150-year-old Ima Keithel or “Mothers's market” complex, which is run exclusively by women and was damaged in the 04 January 2016 earthquake, is returning back to normal. Nine deaths have been reported from in and around Imphal due to falling debris. Imphal has a population of some 270,000 and people were jolted from their sleep and ran out of their homes in panic when the earth shook 04 January, reports say. (Photo by EPA/Stringer)

A five-week-old orphaned Southern Sea Otter pup rests on a rubber mat after arriving at the Shedd Aquarium's Abbott Oceanarium in Chicago, Illinois October 28, 2014 in this handout photo provided to Reuters on November 5, 2014. The stranded pup was found on September 30 on Coastways Beach in California and was rescued the next day to be brought back to health at the Monterey Bay Aquarium. Southern sea otters were listed as “threatened” under the U.S. Endangered Species Act in 1977. (Photo by Brenna Hernandez/Reuters/Shedd Aquarium)

“What created this unusual hole in Mars? The hole was discovered by chance on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars”. (Photo by NASA/JPL/University of Arizona)

A reveler dances during the Carmelitas street party in Rio de Janeiro, Brazil, Friday, March 1, 2019. Much of the appeal of Rio street parties is the variety of themes and that people can dress up in costumes or not. (Photo by Leo Correa/AP Photo)

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)