Two women pose as they drink real ale at the Great British Beer Festival in the Olympia exhibition centre on August 13, 2013 in London, England. The festival, which runs until August 17, 2013, has over 24 bars serving over 800 different beers, ciders and perries. (Photo by Oli Scarff)

“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 man standing on the first cables during the construction of the Golden Gate Bridge with the Presidio and San Francisco in the background, San Francisco, California, 1935. (Photo by Underwood Archives/Getty Images)

A stag reacts as magpies and crows fuss over a resting stag as they feed on ticks from the fur of the deer herd roaming on the Ashton Court Estate, Bristol, in crisp and cold Autumnal weather on November 23, 2020. (Photo by Ben Birchall/PA Images via Getty Images)

Women wearing masks and shields take a selfie in front of a praying altar during Lunar New Year in Chinatown in Manila, Philippines, February 12, 2021. (Photo by Eloisa Lopez/Reuters)

An elephant cools off at a zoo in Karachi, Pakistan, 31 March 2021. Caretakers at Karachi's zoo were working to keep animals cool during a​ heatwave affecting southern Pakistan. (Photo by Shahzaib Akber/EPA/EFE)

Thai dancers use face shield while waiting for worshippers, after the government eased some coronavirus restrictions, at the Erawan shrine, a popular tourists site, in Bangkok, Thailand, 03 May 2020. The Thai government announced that some businesses and shops can reopen and services and some activities can be resumed from 03 May 2020 on as long as social distancing and regulations are in place. (Photo by Narong Sangnak/EPA/EFE/Rex Features/Shutterstock)

A boy attends Eid al-Adha prayers on the street outside Abu Hanifa mosque in Baghdad Adhamiya district, during the outbreak of the coronavirus disease (COVID-19), in Iraq, July 31, 2020. (Photo by Thaier Al-Sudani/Reuters)