A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

It is already one of the world’s most iconic cities, but this incredible collection shows how much Paris has changed over the course of the past century. The collection, by French photographer Julien Knez, shows Paris in the 1940s against a backdrop of how the same places look today. Knez says he put the striking collection together to celebrate the 71st anniversary of the city’s liberation from Nazi control in August 1944. Here: Soldiers outside the Hotel De Ville in the 1940s. (Photo by Julien Knez/Caters News)

“Winter shapes, Moscow river”. Moscow river at this part is never covered by ice. When the temperature is very low it's possible to see a strong fog. Morning light and pipes of the oli factory creates a fantastic landscape. Photo location: Moscow, Russia. (Photo and caption by Sergey Rumyantsev/National Geographic Photo Contest)

21 year-old Chanel Tapper, with the amazing tongue and 35 year-old Aevin Dugas, with the beautiful hair was certified as world record breakers for the world’s longest tongue and the world’s biggest afro in the Guinness Book of World Records. (Photo by Guinness World Records)

Young Ian Archibald ponders the consequences of a complex critical study of beauty contestants during the Miss TV Times finals in London. (Photo by Central Press/Getty Images). 30 July 1971

Starting on Monday, August 12, Perseid meteors will streak across the summer sky for a couple of nights, offering casual stargazers and serious nighttime photographers a chance to capture a glimpse of the annual meteor shower. Photo: Photographer David Kingham created this composite image from 23 photos on August 12, 2012. (Photo by David Kingham)

A runner dressed as Spiderman poses before the annual “Sao Silvestre Run”, an international race through the streets of Sao Paulo, Brazil on December 31, 2021. (Photo by Carla Carniel/Reuters)

Aerial photo taken on April 10, 2022 shows the construction site of Haikou duty-free shopping complex in Haikou, south China's Hainan Province. With a total construction area of about 926,000 square meters, the Haikou duty-free shopping complex project is expected to be officially put into use this year. (Photo by Xinhua News Agency/Rex Features/Shutterstock)