A student wearing a face mask prays before the start of the annual college entrance examination amid the coronavirus pandemic at an exam hall in Seoul, South Korea, Thursday, December 3, 2020. South Korean officials are urging people to remain at home if possible and cancel gatherings as about half a million students prepare for a crucial national college exam. (Photo by Kim Hong-Ji/Pool Photo via AP Photo)

A participant takes part in donkey racing, during the 21st edition of annual Lamu Cultural Festival, in Lamu, Kenya, Saturday December 2, 2023. (Photo by AP Photo/Stringer)

A displaced man cools off to avoid heat on flooded highway, following rains and floods during the monsoon season in Sehwan, Pakistan on September 16, 2022. (Photo by Akhtar Soomro/Reuters)

Racegoers have their temperatures checked as they make their way into the course as a pilot scheme for the return of crowds to sporting events is expected to bring in 2500 spectators during day one of the William Hill St Leger Festival at Doncaster Racecourse, England on September 9, 2020. (Photo by BackGrid/The Sun)

A mother holds her daughter who is injected with a dose of the Soberana-02 COVID-19 vaccine, in Havana, Cuba, Thursday, September 16, 2021. Cuba began inoculating children as young as 2-years-old with locally developed vaccines on Thursday. (Photo by Ramon Espinosa/AP Photo)

Actor Gal Gadot poses with her family during the unveiling ceremony for her star on the Hollywood Walk of Fame in Los Angeles on March 18, 2025. (Photo by Mario Anzuoni/Reuters)

Participants react as they try to reach the top of a greased pole to collect the prizes, during a “Panjat Pinang” competition, that is held to celebrate Indonesia's 79th Independence Day at Ancol in Jakarta, Indonesia, on August 17, 2024. (Photo by Ajeng Dinar Ulfiana/Reuters)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)