Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)

Barbadian singer Rihanna looked incredible as she stripped down to the lacy underwear set for Fenty brand in the last decade of September 2024. (Photo by Savagexfenty)

From the top of a building, Kanon Kennedy, of Washington, looks down at the Black Lives Matter mural as demolition begins, Monday, March 10, 2025, in Washington. (Photo by acquelyn Martin/AP Photo)

Spectators dance in the infield before the 150th running of the Kentucky Derby at Churchill Downs in Louisville, KY on Saturday, May 04, 2024. (Photo by Jabin Botsford/The Washington Post)

A blue-tailed bee-eater chases down its prey along the banks of the Kaveri River on the outskirts of the city of Mysore, India in the last decade of June 2025. (Photo by Nitin Jain/Solent News)

Tourists ride in inflatable boats as they go rafting down a river at Buyun Mountain Scenic Spot on July 10, 2020 in Dalian, Liaoning Province of China. (Photo by Wang Hua/VCG via Getty Images)

Skeleton involves a person riding a small sled down a frozen track while lying face down. The sport is a more intense form of luge because skeleton competitors leap onto the sled and slide downhill head first. Skeleton athletes can reach up to 80 mph on straightaways, causing forces up to 5g, so the helmet is a critical component for attitude as well as safety.