Young Ian Archibald ponders the consequences of a complex critical study of beauty contestants during the Miss TV Times finals in London. (Photo by Central Press/Getty Images). 30 July 1971

Recruits who earned a place in the Motivation Platoon struggle through water and muck on their way to becoming a Marine or going into some other line of work, October 7, 1971. (Photo by Eddie Adams/AP Photo)

Artist Kong Ning wears a wedding dress made from respirators to highlight concerns about air quality and pollution in Beijing, China on December 1, 2015. (Photo by Luo Xiaoguang/Xinhua Press/Corbis)

Finding just the right spot above the clouds at Camp 1 on Ama Dablam, Danuru Sherpa uses his iPhone to catch up with friends and family. Even at 18,500 feet (5,654 meters), climbers here can check their email and other dispatches from the world below. (Photo by Aaron Huey/National Geographic)

Same-sеx marriage supporters kiss outside the Legislative Yuan Friday, May 17, 2019, in Taipei, Taiwan after the legislature passed a law allowing same-sеx marriage in a first for Asia. The vote Friday allows same-sеx couples full legal marriage rights, including in areas such as taxes, insurance and child custody. (Photo by Chiang Ying-ying/AP Photo)

A relative of murdered prisoner, lies on a chair next to his coffin during a wake after a prison riot in the city of Altamira, Para state, Brazil on July 30, 2019. At least 57 prisoners were killed by other inmates during clashes between organized crime groups in the Altamira prison in northern Brazil Monday with 16 of the victims being decapitated, according to prison officials. (Photo by Bruno Kelly/Reuters)

An anti-extradition bill protester throws a stone at a police station in Tseung Kwan O residential district, in Hong Kong, China, August 4, 2019. (Photo by Kim Kyung-Hoon/Reuters)

People in Kathmandu joke that the face mask has now become part of the national dress – an indispensable accessory in an effort to protect themselves from the dust. Nepal has the worst air quality in the world, according to the Environmental Performance Index. (Photo by Pete Pattisson/The Guardian)