A government awareness poster for wearing surgical masks is seen reflected and upside-down in the Dambovita river in Bucharest, Romania, 19 November 2020. The poster, depicting a man wearing a surgical mask, reads: “I WEAR A MASK BECAUSE I KNOW THAT ONLY TOGETHER WE WILL SUCCEED!”. As the number of COVID-19 infections increased, authorities decided that wearing a protective mask should become mandatory at all times in all public places. (Photo by Robert Ghement/EPA/EFE)

Marines finish a 10 kilometer training hike carrying 55 pound (25 kg) packs during Marine Combat Training (MCT) on February 22, 2013 at Camp Lejeune, North Carolina. Since 1988 all non-infantry enlisted male Marines have been required to complete 29 days of basic combat skills training at MCT after graduating from boot camp. MCT has been required for all enlisted female Marines since 1997. About six percent of enlisted Marines are female. (Photo by Scott Olson/AFP Photo)

A Catholic priest blesses a grave, marking All Saints' Day as the people stand next to monument partially destroyed by an old fallen tree at a cemetery in the village of Zubkovo, 150 km (93 miles) west of Minsk, Belarus, Wednesday, November 1, 2017. Belarusian Catholics marked All Saints Day by visiting graves of their relatives. (Photo by Sergei Grits/AP Photo)

Models and designer Lindsay Degen (3rd from L) bare all at the latest DEGEN Spring 2012 presentation during Mercedes Benz Fashion Week at Artisanal House on September 7, 2011 in New York City. (Photo by Earl Gibson III/Getty Images)

Taking it all in at Trolltunga, a piece of rock which juts horizontally out of a mountain, 700 metres above lake Ringedalsvatnet in Norway. (Photo by Sam Rogers/GuardianWitness)

“T'antawawas” (children's bread) are displayed in a popular market to commemorate All Saints Day in La Paz, October 30, 2016. (Photo by David Mercado/Reuters)

A woman poses for pictures with skulls made of cardboard placed on an altar next to the San Francisco church in Mexico City during the celebration of All Souls Day on November 2, 2015. (Photo by Yuri Cortez/AFP Photo)

“A fter the former Soviet Union conducted its first nuclear test in August 1949, the US reevaluated its postwar defense policies. With the US monopoly on atomic weapons broken, military and political leaders chose to diversify the American stockpile by developing thermonuclear and tactical nuclear weapons. One of the more interesting concepts to come out of this period was atomic artillery, which was successfully tested at the Nevada Proving Grounds (now the Nevada Test Site) in May 1953”. – Alan Carr. Photo: Atomic Annie at work during the Upshot-Knothole test series, 1953. (Photo by Los Alamos National Laboratory/US Army)