A stroller walks his dogs in an autumnally colored forest in Cuxhaven, nothern Germany on November 7, 2018. (Photo by Patrik Stollarz/AFP Photo)

Czech Republic's Tomas Machac in action against Norway's Casper Ruud during their men's singles match on day two of the Australian Open tennis tournament in Melbourne on January 17, 2023. (Photo by Hannah Mckay/Reuters)

Cars submerge in water as heavy rain floods the Southern part of the country in Najaf, Iraq on January 04, 2023. (Photo by Karar Essa/Anadolu Agency via Getty Images)

Actresses perform during the Olympic flame lighting ceremony for the Paris 2024 Olympics Games at the Ancient Olympia archeological site, birthplace of the ancient Olympics in southern Greece, on April 16, 2024. (Photo by Angelos Tzortzinis/AFP Photo)

A man is silhouetted in front of the Allianz-Arena as he walks his dogs at sunrise in Munich, southern Germany, Friday, April 10, 2015. (Photo by Peter Kneffel/AP Photo/DPA)

A Somali fisherman carries a sailfish on his head to the Hamarweyne fish market near the port in Mogadishu, Somalia, on January, 5, 2018. (Photo by Mohamed Abdiwahab/AFP Photo)

Iraqi Kurdish women train weight lifting at a centre in Iraq's Kurdish regional capital of Arbil on February 2, 2022. Women's sports have developed at a sluggish pace across much of conservative Iraq, which has struggled through decades of conflict. But the Kurdistan region was spared the brunt of the violence and destruction, and its infrastructure, facilities and government funding have paved the way for a boom in professional women's sports. (Photo by AFP Photo/Stringer)

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)