Mud-covered tourists pretend to be trapped inside a mud prison at the Daecheon Beach Mud Plaza in the city of Boryeong on South Korea's west coast, July 17, as they take part in the Boryeong Mud Festival, which opened that day and runs through July 26. Boryeong mud is rich in natural mineral component and is considered to prevent skin aging. (Photo by EPA/Yonhap)

An injured vulture is treated at the VulPro Vulture Rehabilitation Centre in Hartebeepoortdam in the Magalisburg region on September 15, 2015. Confined to southern Africa, just under 4,000 breeding pairs of Cape Vultures remain in the wild, mostly in South Africa, Lesotho and Botswana. Unless conservation efforts are successful, Africa's largest vulture species may be facing eventual extinction. (Photo by Mujahid Safodien/AFP Photo)

In this photo posted on Twitter, Sunday, May 3, 2015, and provided by NASA, Italian astronaut Samantha Cristoforetti sips espresso from a cup designed for use in zero-gravity, on the International Space Station. Cristoforetti, the first Italian woman in space, fired up the first espresso machine in space, which uses small capsules, or pods, of espresso coffee. (Photo by AP Photo/NASA)

In this photograph taken on April 28, 2018, Afghan children work at a coal yard on the outskirts of Jalalabad, Afghanistan. (Photo by Noorullah Shirzada/AFP Photo)

A gallery staff member walks past Fleeting Monument (1985) by artist Cornelia Parker, one of the works on display at Yorkshire Sculpture Parks Longside Gallery as part of the “Making It: Sculpture in Britain 1977-1986” exhibition on March 27, 2015 in Barnsley, England. (Photo by Christopher Furlong/Getty Images)

A group of women dance in a pool in Callao, Peru, Sunday, February 22, 2015. One of centers for the front-doorstep, pool-party phenomenon is Lima's port city of Callao. People hold parties in them and sometimes entire blocks chip in to buy a pool, which can be had in local department stores for a bit over $100. (Photo by Martin Mejia/AP Photo)

A person dressed as “bigfoot” makes their way through the strong wind and snow in the Back Bay neighborhood during a blizzard on January 27, 2015 in Boston, Massachusetts. (Photo by Kayana Szymczak/Getty Images)

People attend a Halloween event at Ocean Park on October 30, 2015 in Hong Kong. Halloween – a named taken from 'All Hallows' Even' falls on the day before All Saints' Day on November 1 – a holiday when Christians remember their deceased loved ones. (Photo by Anthony Kwan/Getty Images)