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)

Wide-angle category winner. Part of the Illusion by Marcus Blatchford (UK). Location: National Dive & Activity Centre, Chepstow, Wales. “This is the deepest inland dive centre in the UK. The dive plan was to explore the deep end, but this time I dived ‘unplugged’ (without my strobes). With the exception of this change to my camera technique, there were no planned shots I wanted to achieve – just a fun dive with ad-hoc photos along the way. Shortly after this photo was captured, in 6C water and two hours of decompression ahead of us, we turned and started the long ascent back to the surface”. (Photo by Marcus Blatchford/Underwater Photographer of the Year 2016)

A Bengal tiger licks a glass enclosure during a presentation of Bengial tiger cubs at the Malabon Zoo in Malabon City, north of Manila, Philippines, 14 July 2016. The Bengal tiger cubs, which were born at the zoo, are two months old and named “Tiger Duterte” and “Tiger Leni”. The Malabon Zoo has one of the largest private collections of exotic and endemic animals in the Philippines. (Photo by Mark R. Cristino/EPA)

“Lofoten Glow”. I was desperately searching a good sunrise spot this particular morning. Normally Storvatnet Lake is completely covered in snow, so you can only imagine my surprise when I saw these crazy ice formations almost being shot out of the frozen lake. I put my crampons on and took a big risk walking out. I could hear the ice cracking underneath my feet, and when you’re all alone in a fjord/canyon like this – the cracks are echoed and sound really frightening. Was it worth it? I sure think so! Photo location: Storvatnet, Lofoten Islands in Northern Norway. (Photo and caption by Stian Klo/National Geographic Photo Contest)

In this photo taken on Monday, October 27, 2014, a cactus stands at a broken window in a damaged house after shelling not far from Donetsk airport in the town of Donetsk, eastern Ukraine. Donetsk, which has lost about 400,000 of its 1 million pre-war population, is bracing to a winter ahead. In a climate like eastern Ukraine's, where temperatures typically stay below zero all winter, the damage to the critical infrastructure and lack of effort to provide adequate shelter to people whose homes were destroyed could literally mean a death from the cold. (Photo by Dmitry Lovetsky/AP Photo)

Supporters enjoy the atmosphere before watching England's second World Cup match against USA on the big screen at Road to Victory, Europe's largest World Cup fan park at Mayfield Depot on November 25, 2022 in Manchester, England. The English team came into their second World Cup 2022 match favoured to win. (Photo by Anthony Devlin/Getty Images)

Chileans watch the sky with special suits prior to a total solar eclipse on July 2, 2019 in Paiguano, Chile. Around 25,0000 tourists arrived to Paiguano, a small town of around 1,000 inhabitants in the Elqui Valley, 650 km away Santiago. This is the only Earth's total solar eclipse of 2019 and the first one since 2017. From this point, the sun will fully disappear for around two minutes. It is best visible from a stripe in the South Pacific, Chile and Argentina. (Photo by Marcelo Hernandez/Getty Images)

In this file photo taken on Saturday May 1, 1993, an elderly communist woman clutches her head as police on horseback patrol the streets in Moscow. When Alexander Zemlianichenko started working as an AP photographer in Moscow, the Soviet Union was nearing its demise. (Photo by Alexander Zemlianichenko/AP Photo)