Family members pose for photos near lava flowing from Pacaya Volcano near El Patrocinio village in San Vicente Pacaya, Guatemala, Friday, April 16, 2021. (Photo by Moises Castillo/AP Photo)

A man cools off under a pipe of flowing water on a hot summer day in New Delhi, India, May 11, 2022. (Photo by Anushree Fadnavis/Reuters)

A girl holds onto a pole as as she stands in floodwaters flowing from the swollen Bagmati River caused by heavy rainfall in Kathmandu, Nepal August 17, 2015. (Photo by Navesh Chitrakar/Reuters)

People gather to watch the eruption of the Mauna Loa Volcano while the lava flow is covered with the clouds in Hawaii, U.S. December 3, 2022. (Photo by Go Nakamura/Reuters)

Lava crosses the main road to Grindavík and flows on the road leading to the Blue Lagoon, in Grindavík, Iceland, Thursday, February 8, 2024. (Photo by Marco Di Marco/AP Photo)

Long streams of red-hot lava flow down the southeast crater of Mount Etna, Europe's tallest and most active volcano, seen from Zafferana Etnea, Italy, June 11, 2022. (Photo by Antonio Parrinello/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)