“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)

Wildlife officials carry away the carcass of a turtle that was washed ashore at the beach of Angulana, south of Sri Lanka's capital Colombo on June 24, 2021. (Photo by Ishara S. Kodikara/AFP Photo)

In a photo taken on April 2, 2020 a staff member feeds a raccoon at the Table A Raccoon Cafe in Seoul. Business has been devastated by the coronavirus outbreak, with South Koreans staying at home under social distancing guidelines, and tourism disappearing. But unlike other firms, animal cafes have to stay open so that staff can look after their stock. (Photo by Ed Jones/AFP Photo)

A mahout washes an elephant in the river in Pinnawala, some 95 kms from the capital Colombo on April 15, 2020. (Photo by Ishara S. Kodikara/AFP Photo)

A mother reacts as she pleads with police to allow her daughter to pass a checkpoint for cancer treatment after she arrived from Hubei province at the Jiujiang Yangtze River Bridge in Jiujiang, China, February 1, 2020. (Photo by Thomas Peter/Reuters)

A train attendant wearing a protective face mask stands on a train to Wuhan, at the railway station in Beijing, China, 29 March 2020. Wuhan, the epicenter of the coronavirus outbreak, partly lifted the lockdown allowing people to enter the city after more than two months. Chinese authorities eased the quarantine measures as cases of Covid-19 across China have plummeted, according to Chinese government figures. (Photo by Roman Pilipey/EPA/EFE)

Daredevil motorcycle rider Captain Shivam Singh (C) from the “Tornadoes” motorcycle acrobatic team of the Indian Armed Forces comes out ablaze after catching fire while riding his bike through a tunnel of fire during an attempt to break the Guinness Book of World Records in Bangalore on November 10, 2020. Shivam Singh broke the Guinness Book of World Records passing 127 m and escaped with minor injuries. (Photo by Manjunath Kiran/AFP Photo)

People walk along the sea front at Blyth in Northumberland in North East England on Monday, May 24, 2021. (Photo by Owen Humphreys/PA Images via Getty Images)