Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

A soldier stands guard on the aircraft park of the Pyongyang Airport on April 3, 2011 in Pyongyang, North Korea. Pyongyang is the capital city of North Korea and the population is about 2,500,000.

Afghan children wait as their mothers receive treatment at a USAID-funded health center on September 7, 2011 in Farza, Afghanistan. Almost 10 years after the 9/11 attacks and the U.S. invasion of Afghanistan, the U.S. government funds some of 500 Afghan health facilities nationwide, most run by non-governmental organizations contracted by the Afghan Ministry of Public Health. (Photo by John Moore/Getty Images)

Burmese monks take their yearly exam December 13, 2011 in Bago, Myanmar. Around 1,400 monks from Bago province took part . (Photo by Paula Bronstein /Getty Images)

Volodymyr, a service member of the Ukrainian armed forces, plays with puppies at fighting positions on the line of separation from pro-Russian rebels in Donetsk region, Ukraine on April 10, 2021. The two unnamed puppies living on frontline positions will be taken home and named by soldiers departing on troops rotation. (Photo by Oleksandr Klymenko/Reuters)

A Police officer reacts to protestors outside the Piet Retief Magistrates court where the five accused in the shooting of the Coka brothers on the Pampoenkraal farm appeared, Mhkondo, Mpumalanga, South Africa on April 19, 2021. (Photo by Jacques Nelles)

The rusty emblem of the Soviet Union is seen over the ghost town of Pripyat close to the Chernobyl nuclear plant, Ukraine, Thursday, April 15, 2021. The vast and empty Chernobyl Exclusion Zone around the site of the world’s worst nuclear accident is a baleful monument to human mistakes. Yet 35 years after a power plant reactor exploded, Ukrainians also look to it for inspiration, solace and income. (Photo by Efrem Lukatsky/AP Photo)