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)

Children play in the Crown Fountain at Millennium Park in Chicago, Wednesday, June 29, 2022. (Photo by Nam Y. Huh/AP Photo)

A bride gets her make-up done before the start of a mass marriage ceremony in Kolkata, India, February 14, 2016. A total of 150 tribal Hindu, Muslim and Christian couples from various villages across the state took their wedding vows on Sunday during the day-long mass marriage ceremony organised by a social organisation, the organisers said. (Photo by Rupak De Chowdhuri/Reuters)

“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)

Monty, (C) the Wadworth brewery shire horse gets given a pint of beer outside the Raven Inn in Poulshot as he starts his two-week annual holiday on August 3, 2012 near Devizes, England. (Photo by Matt Cardy)

in Qayyarah, about 31 miles (50 km) south of Mosul, Iraq, Sunday, October 23, 2016.in Qayyarah, some 50 kilometers south of Mosul, Iraq, Sunday, Oct. 23, 2016. Islamic State fighters torched a sulfur plant south of Mosul, sending a cloud of toxic fumes into the air that mingled with oil wells the militants had lit on fire to create a smoke screen. (Photo by Marko Drobnjakovic/AP Photo)

German Nazi leader Adolf Hitler (1889 - 1945) enjoys a quiet picnic between meetings, circa 1933. Picture 196 of a series of collectable images published in Germany during the Nazi period, entitled “Deutschland Erwacht” (Germany Awakes). (Photo by Heinrich Hoffmann/Hulton Archive/Getty Images)

Olena Korzeniuk, a 15-year-old girl poses on the stairs during a bid to set the national record for the longest hair on a child in Kiev, Ukraine on March 12, 2019. During a ceremony, the experts of the National Register of Records found the blonde hair of the Ukrainian Rapunzel to be 2.35m (6.5ft) long. (Photo by Tarasov/Ukrinform/Barcroft Images)