“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)

First prize. Taken over Bali Barat National Park, Denpasar, Bali. Made with a GoPro Hero 2 camera. (Photo by Capungaero)

“I was on Durga Puja Festival vacation, travelling on a local train. A boy was singing devotional song and begging for alms. He was guised as a Hindu god, Lord Shiva. This is a common view in Indian trains but this boy was charming, bright and did have a melodious voice. My camera was ready hanging on my neck so I took a picture”. (Photo and caption by Arup Ghosh/2014 Sony World Photography Awards)

A Kashmiri woman walks on a footbridge as it rains in Srinagar, June 24, 2015. This year's monsoon rains in India are officially forecast to be only 88 percent of the long-term average. (Photo by Danish Ismail/Reuters)

It has become tradition in Wigan in Greater Manchester, United Kingdom for residents to go out on the town in fancy dress for Boxing Day on Sunday, December 26, 2021. Boxing Day is a holiday celebrated after Christmas Day, occurring on the second day of Christmastide. (Photo by Joel Goodman/London News Pictures)

Competitors take part in the Rude Health World Bog Snorkelling Championships at Waen Rhydd peat bog in Llanwrtyd Wells, Wales on Sunday, August 27, 2023. (Photo by Ben Birchall/PA Images via Getty Images)

3-year-old Myla Mills plays with a two day old lamb in a toy pram in her family's farmyard in Arley, Worcestershire, United Kingdom on January 28, 2023. Early lambs are produced when the ram is free to tup the ewes over winter. (Photo by Peter Lopeman/Alamy Live News)

Two female holidaymakers relax on an unidentified beach of England, September 21, 1940, as a soldier, eyes straight ahead, stands guard at a barrier built as a defense against possible invasion by Germany. (Photo by AP Photo)