Medical personnel jump in the COVID-19 unit at the CHR Centre Hospitalier Regional de la Citadelle Hospital, during the coronavirus disease (COVID-19) outbreak, in Liege, Belgium, April 22, 2020. (Photo by Yves Herman/Reuters)

People dressed as zombies participate in a parade for World Zombie Day 2016 in London's West End, Britain on October 9, 2016. (Photo by Splash News and Pictures)

Visitors take photos of the fluorescent sea in the waters of Paishi Village, Dalian City, Liaoning Province, China, May 24, 2020, from the night of May 24 to the early morning of May 25, 2020. The fluorescent sea in dalian is caused by noctilucent algae in the sea water. (Photo by Costfoto/Barcroft Media via Getty Images)

A staff member sets up a ROBOTLEO robot at the Global Mobile Internet Conference (GMIC) 2017 in Beijing, China April 28, 2017. (Photo by Jason Lee/Reuters)

A girl in an angel costume walks with her family past vegetable vendors in Havana, Cuba, Wednesday, April 10, 2019. (Photo by Ramon Espinosa/AP Photo)

A member of the wingsuit flyers duo, known as the Soul Flyers, is seen in mid-air as he catches up and flies into the open door of Pilatus Porter plane, piloted by Philippe Bouvier, after B.A.S.E. jumping off the Jungfrau mountain, 4158 meters, in Lauterbrunnen, Switzerland, October 13, 2017. French athletes Fred Fugen and Vince Reffet had 2.45 minutes and a free fall distance of 3200 meters to complete their project “Door In The Sky”, coordinated by Yves Rossy know as the “Jetman”. (Photo by Thibault Gachet/Reuters)

People mourn next to the body of Muddasir Khan, who was wounded on Tuesday in a clash between people demonstrating for and against a new citizenship law, after he succumbed to his injuries, in a riot affected area in New Delhi, February 27, 2020. (Photo by Adnan Abidi/Reuters)

A competitor shouts as he takes part in the “Tough Guy” adventure race near Wolverhampton, central England, on January 29, 2017. The Tough Guy event, which is being held for the final time in its 30th year, challenges thousands of competitors to run a gruelling course whilst negotiating over 200 obstacles including: water, fire, and tunnels. (Photo by Oli Scarff/AFP Photo)