Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

A medical worker in protective gear sprays mist on her colleague during a hot day at an outdoor clinic for coronavirus tests at a public health facility in the southwestern city of Gwangju, South Korea, 05 June 2020. (Photo by Yonhap/EPA/EFE)

Ammunition airlift into besieged Khe Sanh, Operation Pegasus, April 1968. (Photo by Larry Burrows/AP Photo)

A helicopter flies in front of the Wolf Moon as it rises over London, England on January 20, 2019. The Wolf Moon, the Full Moon on January 20-21, 2019, is a Supermoon, making it look bigger and brighter than usual during the total lunar eclipse. (Photo by Dinendra Haria/Rex Features/Shutterstock)

A dog wearing face mask is seen on a street as the country is hit by an outbreak of the novel coronavirus, in Shanghai, China on March 2, 2020. (Photo by Aly Song/Reuters)

Yan Anyu or Miss Cream rides in a taxi in Shanghai on June 13, 2020, as she makes her way to a bar in the city of Shanghai to make her first presentation as a drag queen. Attitudes toward alternative lifestyles are slowly softening in China, and members of a small but growing drag community have begun to step into the spotlight. (Photo by Hector Retamal/AFP Photo)

Giant pandas play in the snow at the Shenshuping Base of China Conservation and Research Center for the Giant Panda on January 13, 2022 in Aba Tibetan and Qiang Autonomous Prefecture, Sichuan Province of China. (Photo by Chen Xianlin/VCG via Getty Images)

A military instructor teaches a schoolboy shooting with Kalashnikov rifles, during a training session at a military unit of the National Guard of Ukraine in western Ukrainian city of Lviv on February 15, 2022. (Photo by Yuriy Dyachyshyn/AFP Photo)