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)

Mosaïcultures Internationales de Montréal is an international mosaiculture competition held in Montréal, Canada. According to their website, mosaiculture “is a refined horticultural art that involves creating and mounting living artworks made primarily from plants with colourful foliage (generally annuals, and occasionally perennials).” The 2013 competition and exhibition opened June 22 and runs through September 29 at the Montréal Botanical Garden and features some 22,000 plant species and cultivars distributed throughout 10 exhibition greenhouses and 30 themed gardens.

Max Gold, 20, of NYC, cruises on his skateboard as thousands gather on the National Mall for the March for Science on Saturday, April 22, 2017, in Washington, DC. Activists and scientists descend on the nation's capital to rally for environmental causes and government policies rooted in scientific research as part of the Earth Day and March for Science rallies. (Photo by Jahi Chikwendiu/The Washington Post)

Juanita Robinson (L) from Ohio and Trenaya Blackburn pose as Quan White from Michigan takes their picture as they vacation on South Beach on May 16, 2016 in Miami Beach, Florida. The Florida government announced it broke a tourism record in the first quarter of this year, attracting 29.8 million tourists, an increase of 4.8 percent over the same time frame in 2015. (Photo by Joe Raedle/AFP Photo)

A Minion character dressed in a Christmas theme is pictured in Times Square during unseasonably warm weather on Christmas Eve in the Manhattan borough of New York, December 24, 2015. (Photo by Carlo Allegri/Reuters)

A man dressed as the Sesame Street character Big Bird sits on a bench waiting to take pictures with people walking through Central Park in New York U.S., November 14, 2016. (Photo by Shannon Stapleton/Reuters)

A man dressed in Christmas garb smokes a hand-rolled cigarette, Thursday, December 24, 2020, in Times Square on Christmas Eve in New York. (Photo by Kathy Willens/AP Photo)

Supporters of US President Donald J. Trump gather for a rally in Freedom Plaza to protest Congress's upcoming certification of Joe Biden as the next president in Washington, DC, USA, 05 January 2021. Various groups of Trump supporters announced rallies on 06 January 2021 as Congress meets to certify the results of the 2020 US Presidential election. (Photo by Shawn Thew/EPA/EFE)