Omar Gamal, a 28-year-old pigeon keeper, stands next to his pigeon coop on his rooftop in the Egyptian capital's twin city of Giza on February 21, 2021, with the Pyramids of (R to L) Khufu (Cheops), Khafre (Chephren), and Menkaure (Menkheres) in the background. An ancient tradition handed down through the generations, the practice of domesticating pigeons stretches across borders from the banks of the Nile to north Africa and beyond, with people not only training birds for competitions, but also serving them up as a dining delicacy. (Photo by Khaled Desouki/AFP Photo)

Bolivia's president Evo Morales holds his scared staffs of power during a blessing by Aymaran spiritual guides, in a traditional ceremony at the archeological site Tiwanaku, Bolivia, Wednesday, January 21, 2015. Morales is set to begin a new term Thursday, that will make him the Andean nation's longest-serving leader, riding high on a wave of unprecedented growth and stability. (Photo by Juan Karita/AP Photo)

“NASA's Pathfinder, Pathfinder Plus, Centurion and Helios Prototype were an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. They were built to develop the technologies that would allow long-term, high-altitude aircraft to serve as “atmospheric satellites”, to perform atmospheric research tasks as well as serve as communications platforms”. – Wikipedia

Photo: The solar-electric Helios Prototype flying wing is flies over the Hawaiian islands of Niihau and Lehua during the first solar-powered test flight July 14, 2001 from the U.S. Navy's Pacific Missile Range Facility on Kauai, HI. The 18-hour flight was a functional checkout of the aircraft's systems and performance in preparation for an attempt to reach sustained flight at 100,000 feet altitude later in the summer. (Photo Courtesy of NASA/Getty Images)

A Ukrainian girl plays with balloons with the colours of her country's flag aboard the Corsica Linea ferry “Mediterranee” in Marseille, southern France, on April 26, 2022. Anna and her children enjoy the sun on the deck of a ferry moored in Marseille: they are not vacationers but Ukrainian refugees who, on this boat, have finally found safety, “like in a village”, with 700 others compatriots. The “Mediterranean” usually serves Algeria, for the Corsica Linea. But it is now docked, at the Joliette ferry terminal in Marseille, with its unusual passengers. (Photo by Nicolas Tucat/AFP Photo)

A body surfer rides a high wave at the Wedge on September 1, 2011 in Newport Beach, California. Waves measuring up to 20 feet pounded the beach. A winter storm off the coast of Australia and New Zealand brought unusally hgh serve to the Southern California beaches. (Photo by Kevork Djansezian/Getty Images)

A woman poses as she has her picture taken amid 1600 panda bear sculptures in Berlin August 5, 2013. Marking the 50th anniversary of its existence, on Monday the German branch of the World Wide Fund for Nature (WWF) environmental conservation organisation placed 1600 panda bear sculptures on front of Berlin's main train station to draw attention to the plight of the endangered species that serves as the NGO's mascot. There are currently 1600 panda bears alive in the wild, the organisation said in a press release. (Photo by Thomas Peter/Reuters)

The maid-themed cafe in Hangzhou, China on September 29, 2016. A cafe has been bringing in droves of new customers after hiring young women to dress up in Frech maid costumes while serving diners. Curious coffee- and coffee-lovers are coming from all corners of Hangzhou, capital of East China's Zhejiang Province, to get a taste of the “maid cafe” experience. The business is said to have been opened by a man surnamed Yu and his friends, all whom are natives or graduates of the city. The all-female staff who donned the black and white French maid outfits are also students currenting living or studying in Hangzhou, allowing them to marry their passion for serving with the part-time job. (Photo by AsiaWire)

Chinese conglomerate Tiens Group employers take photos while waiting to be served Paella in Madrid, Spain, Friday, May 6, 2016. The billionaire founder of Chinese conglomerate Tiens Group is treating 3,000 of his best salespeople to a traditional Spanish paella meal in a free Madrid trip that also includes a bullfight and a tour of King Felipe VI's Royal Palace. The smiling salespeople washed down their heaping plates of paella with sangria Friday at a mass spread of picnic tables in a riverside park during the event footed by Li Jinyuan and organized by China's U Tour travel company. (Photo by Paul White/AP Photo)