On the western side of Mount Hood lies the longest glacier cave system in the contiguous United States. In 2012, these caves were mapped to a combined length of 7,166.8 feet by cave explorers Brent McGregor and Eddy Cartaya. Currently, the total passage length is hundreds of feet less. Glaciers are frozen rivers; they are always moving and changing... (Photo and caption by Josh Hydeman)

Zhou Xiaoxuan, center, weeps as she speaks to her supporters upon arrival at a courthouse in Beijing, Wednesday, December 2, 2020. Zhou, a Chinese woman who filed a sexual harassment lawsuit against a TV host, told dozens of cheering supporters at a courthouse Wednesday she hopes her case will encourage other victims of gender violence in a system that gives them few options to pursue complaints. (Photo by Andy Wong/AP Photo)

Spot, a robot with dog-like movements, walks past a dog in Cathedral Square in Erfurt, Germany on April 20, 2021. Security service provider Ciborius, a provider of robotic security solutions with artificial intelligence, presented its artificial employee with high-resolution 360-degree all-round camera, ultra-bright LED light and a light detection system on Domplatz. (Photo by Michael Reichel/dpa)

Muqtada Haider turns the switches to transfer electricity to private homes in Baghdad, Iraq, Friday, September 10, 2021. In Iraq, electricity is a potent symbol of endemic corruption, rooted in the country’s sectarian power-sharing system. This contributes to chronic electrical outages of up to 14 hours a day in a major oil-producing nation with plentiful energy resources. (Photo by Hadi Mizban/AP Photo)

Air conditioners, more than 500 in total, hang on the wall of an office building on August 15, 2011 in Fuzhou, Fujiang Province of China. This 25-story office building was built with no central air conditioner system, each office has it own individual unit installed on the exterior creating this wall of air conditioners. (Photo by ChinaFotoPress/Getty Images)

Zookeepers measure the length of a pueblan milk snake in the Reptile House of ZSL London Zoo as part of their annual weighing and measuring of their animals on August 25, 2011 in London, England. The heights and weights of over 750 different animal species at the zoo are recorded into the International Species Information System, to monitor their health and share the data with other zoos across the world. (Photo by Oli Scarff/Getty Images)

In this November 3, 2019, photograph a child with Down syndrome jokingly gestures to the audience while presenting ponchos displaying drawings inspired by children, during a fashion show dubbed “heART Couture” in Bucharest, Romania.Children with Down syndrome staged a fashion show and performed along a ballet ensemble, two milestone events for the inclusion of people with disabilities in Romania's social life, 30 years after the fall of communism following a violent uprising at the end of 1989. (Photo by Vadim Ghirda/AP Photo)