“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 Burmese monk feeds the seagulls at a Yangon river jetty February 8, 2012 in Yangon, Myanmar. (Photo by Paula Bronstein/Getty Images)

Behishta,11, listens during 4th grade class at the Zarghoona high school on July 25 2021 in Kabul, Afghanistan. The Zarghoona girls high school is the largest in Kabul with 8,500 female students attending classes. The school opened after a nearly two-month break due to the coronavirus (COVID-19) pandemic. (Photo by Paula Bronstein/Getty Images)

Nail salon Maniqure owner Lim Pei Xin works on a Squid Game's manicure for a client at her shop in Kuala Lumpur, Malaysia on October 14, 2021. (Photo by Lim Huey Teng/Reuters)

A student gets off a police vehicle which carried her to a high school to arrive in time for a college entrance exam in Seoul, South Korea, Thursday, November 18, 2021. About 510,000 high school seniors and graduates across the country are expected to take the College Scholastic Ability Test. (Photo by Ahn Young-joon/AP Photo)

A boy, who came with the humanitarian transport of children from Ukrainian public orphanages following the Russian invasion of Ukraine, reacts as he has breakfast at the Hotel Ossa near Rawa Mazowiecka, Poland on March 5, 2022. (Photo by Kacper Pempel/Reuters)

Family members and relatives of passengers on board the Twin Otter aircraft operated by Tara Air, weep outside the airport in Pokhara on May 29, 2022. A passenger plane with 22 people on board went missing in Nepal on May 29, the operating airline and officials said, as poor weather hampered a search operation. (Photo by Prakash Mathema/AFP Photo)

An Ezo red fox, or kitakitsune, and her cub are seen at night near the city of Sapporo, northern Japan, 15 May 2022. Authorities are calling population to avoid contact with the animals due to risks of echinococcosis infection. (Photo by JIJI Press/EPA/EFE)