An Afghan policeman stands guard as smoke and flames rise from the site of a huge blast struck near the entrance of Kabul's international airport, in Kabul on August 10, 2015. A huge blast struck near the entrance of Kabul's international airport on August 10 during the peak lunchtime period, officials said, warning that heavy casualties were expected. “The explosion occurred at the first check point of Kabul airport”, said deputy Kabul police chief Sayed Gul Agha Rouhani. (Photo by Shah Marai/AFP Photo)

Syrian fighters from the Turkish-backed National Liberation Front (NLF) fire a missile against regime positions on May 13, 2019 in the rebel-held northern part of Syria's Hama province. Clashes on the edge of a jihadist bastion in northwestern Syria have killed at least 42 fighters in 24 hours, a monitor said today, after regime bombardment on the region devastated health services. (Photo by Omar Haj Kadour/AFP Photo)

A hiker walks in the Zillertal Alps during an autumn day near the village of Ginzling, Austria, October 15, 2019. (Photo by Lisi Niesner/Reuters)

Belarusian schoolchildren, who are members of a pro-government Young Pioneer movement, perform with drums as they take part in a meeting to mark the 95th anniversary of their organisation in Minsk, Belarus May 19, 2017. (Photo by Vasily Fedosenko/Reuters)

A woman walks under snowfall in front of a Soyuz rocket installed as a monument in Baikonur city, near the Russian leased Kazakh Baikonur cosmodrome on December 5, 2021. Space tourists Yusaku Maezawa and his assistant Yozo Hirano, led by Roscosmos cosmonaut Alexander Misurkin, will take part in a mission on the Soyuz MS-20 spacecraft to the International Space Station (ISS) scheduled for December 8, 2021. (Photo by Kirill Kudryavtsev/AFP Photo)

A girl carries a picture of Sheikh Nimr al-Nimr, who was executed along with others in Saudi Arabia, during a protest against the execution in front of the United Nation's building in Beirut, Lebanon January 3, 2016. Sign reads, “The martyr scholar Nimr al-Nimr”. (Photo by Hasan Shaaban/Reuters)

A wounded Syrian girl looks on at a make shift hospital in the rebel-held area of Douma, east of the capital Damascus, following shelling and air raids by Syrian government forces on August 22, 2015. At least 20 civilians and wounded or trapped 200 in Douma, a monitoring group said, just six days after regime air strikes killed more than 100 people and sparked international condemnation of one of the bloodiest government attacks in Syria's war. (Photo by Abd Doumany/AFP Photo)

“Aurora Hunters”. Photographers taking part in a photography tour on the Lofoten Islands in Norway, pull over on the side of the road to take a photo of their first ever Aurora Borealis after spotting it from their tour bus. Photo location: Rystad, Lofoten Islands, Norway. (Photo and caption by Mark Gee/National Geographic Photo Contest)