“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)

Woolland Woods, Dorset. Landscape photographer of the year 2020. “Taken in spring of 2018 in a wooded area close to Milborne St Andrew in Dorset, this was the third visit to the area in a matter of days. On the previous days, both devoid of morning mists, the light had been harsh and unappealing but the third day delivered stunning conditions with mist swirling through the trees. The low shooting position allowed more emphasis to be placed on the wild garlic and pathway”. (Photo by Chris Frost/UK Landscape Photographer of the Year 2020)

Experts of the Anti-Mine Center of the Russian Defense Ministry clear mines at a motorway linking the cities of Stepanakert and Goris in Nagorno-Karabakh on November 23, 2020. (Photo by Stanislav Krasilnikov/TASS)

A flight crew from China Airlines, wearing protective masks, stand in the international terminal after arriving on a flight from Taipei at Los Angeles International Airport (LAX) on February 28, 2020 in Los Angeles, California. The World Health Organization (WHO) has raised the global coronavirus risk level to “very high”. (Photo by Mario Tama/Getty Images)

Young women wearing facemasks and traditional costumes of Song dynasty and Tang dynasty are seated on a bench in a park next to the East Lake in Wuhan, in China’s central Hubei province on May 17, 2020. The Guardian picture desk has chosen on December 17, 2020, the AFP photojournalist Hector Retamal as “Agency Photographer of the Year 2020” for his coverage of the novel coronavirus Covid-19 pandemic in Wuhan, China. (Photo by Hector Retamal/AFP Photo)

Gabriel Berendo, a businessman and car enthusiast, drives a casket converted into a car on Sunday May 31, 2020 in Cebu city, central Philippines as he goes around streets to remind residents to stay at home as lockdown measures to prevent the spread of the new coronavirus eases next week. (Photo by AP Photo/Stringer)

This handout photo taken on March 8, 2021 and released on March 9 by the Myitkyina News Journal shows a nun pleading with police not to harm protesters in Myitkyina in Myanmar's Kachin state, amid a crackdown on demonstrations against the military coup. (Photo by Myitkyina News Journal/Handout via AFP Photo)

An Afghan girl stand in the doorway of her home in Kabul, Afghanistan, Monday, March 29, 2021. (Photo by Rahmat Gul/AP Photo)