A man runs after he tried to put himself on fire during a protest at a makeshift camp at the Greek-Macedonian border near the village of Idomeni on March 22, 2016. Greece will not be able to start sending refugees back to Turkey from March 20, 2016, the government said, as the country struggles to implement a key deal aimed at easing Europe's migrant crisis. The numbers are daunting: officials said as of Saturday there were 47,500 migrants in Greece, including 8,200 on the islands and 10,500 massed at the Idomeni camp on the Macedonian border. (Photo by Andrej Isakovic/AFP Photo)

These beautiful shots may look like works of modern art – but they are actually close-ups of chemical reactions. The works were snapped with the help of a group of scientists from the University of Science and Technology of China (USTC) in Anhui, China. Here: Zinc reacting with lead nitrate in a soft gel to form lead crystals. (Photo by Yan Liang/Caters News)

A woman directs traffic in the pouring rain in Pyongyang, North Korea on May 3, 2016. The city is preparing for the Workers' Party Congress starting on May 6th. It will be the first time since 1980 that the ruling party has convened. (Photo by Linda Davidson/The Washington Post)

A young vendor hawks food on a market in Kara in the state of Ogun, on September 23, 2015. Nigeria imposed tight movement restrictions in the restive northeast after Boko Haram bombings that killed more than 100 raised fears of fresh attacks over the Eid al-Adha festival. The military said the use of all vehicles would be banned throughout Borno state during the Muslim festival, which is known as Sallah in Nigeria and marked with two days' public holiday from Thursday. (Photo by Pius Utomi Ekpei/AFP Photo)

A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

A child is seen during celebrations of Reindeer Breeder Day, the main holiday of indigenous peoples of the Russian Extreme North, in the village of Nosok on Taymyr Peninsula in north-central Siberia, Krasnoyarsk Territory, Russia on April 17, 2021. (Photo by Alexander Ryumin/TASS)

Choo Gaeun of South Korea reacts during competition with Jin Jongoh of South Korea during the mixed 10m air pistol team qualification during Tokyo 2020 Olympics at Asaka Shooting Range in Tokyo, Japan on July 27, 2021. (Photo by Ann Wang/Reuters)

A child sitting in a washbowl filled with water cools himself as civilians struggle with protecting themselves from the dangers of extreme heat at the refugee camp, in Idlib, Syria on July 13, 2023. The civilians, who fled from the attacks of the Syrian Army, live under harsh conditions without infrastructure and electricity while the temperature reaches 47 Celsius in the region. (Photo by Izzeddin Kasim/Anadolu Agency via Getty Images)