A nurse at St. Joseph's Hospital wears a unique mask as the hospital celebrates the release of a COVID-19 patient after 45 days in their care during the outbreak of the coronavirus disease (COVID-19) in Orange, California, U.S., May 5, 2020. (Photo by Mike Blake/Reuters)

A guard stands at Dityatki checkpoint, marking a 30 km (18-mile) zone around the Chernobyl nuclear power plant April 23, 2013. Ukraine will mark the 27th anniversary of the Chernobyl disaster, the world's worst civil nuclear accident, on April 26. (Photo by Gleb Garanich/Reuters)

A protester carries a child march during a demonstration against the February 1 military coup in Yangon on February 10, 2021. (Photo by Ye Aung Thu/AFP Photo)

Palestinian groom Mohamed abu Daga and his bride Israa wear face masks amid the COVID-19 epidemic, during a photoshoot at a studio before their wedding ceremony in Khan Yunis in the southern Gaza Strip, on March 23, 2020. Authorities in Gaza confirmed on March 22 the first two cases of novel coronavirus, identifying them as Palestinians who had travelled to Pakistan and were being held in quarantine since their return, as the United Nations warned of potential disastrous outcomes to an outbreak given the high poverty rates and weak health system in the coastal strip, under Israeli blockade since 2007. (Photo by Said Khatib/AFP Photo)

Argentinian dancer Maria Belen Ciaschi, stranded in Lebanon due to COVID-19 coronavirus pandemic, dances flamenco to the music played by Uruguayan singer Walter Javier Maulelo while both wearing a mask on a seafront boardwalk in the northern coastal city of Batroun, on April 15, 2020. (Photo by Ibrahim Chalhoub/AFP Photo)

A tourist gets an “Art Hug” from a disinfected costumed man outside the reopened Rijksmuseum in Amsterdam, Netherlands, Monday, June 1, 2020. The government takes a major step to relax the coronavirus lockdown, with bars, restaurants, cinemas and museums reopening under strict conditions. (Photo by Peter Dejong/AP Photo)

Two sheep fight in a competition in Zhangjiakou, Hebei province, China on August 1, 2017. (Photo by Reuters/China Stringer Network)

The First U.S. Spacewalk – Gemini 4 Ed White made the United States' first spacewalk on June 3, 1965 during the Gemini 4 mission. The extra-vehicular activity (EVA) started at 19:45 UT (3:45 p.m. EDT) on the third orbit when White opened his hatch and used the hand-held manuevering oxygen-jet gun to push himself out of the capsule. (Photo by NASA)