“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 mermaids swims during MerMagic Con at the Freedom Aquatic Center in Manassas, Virginia on August 7, 2021. MerMagic Con is advertised as the largest Mermaid convention in the world. Some parts of the convention are based on modeling and looks like the Miss Mermaid USA Pageant. The Society of Fat Mermaids looks to bring together plus size people and promote the idea that anyone can become a mermaid. Becoming a mermaid is not cheap, most merfolk spend thousands of dollars on their tail and outfit. Most tails are custom made out of silicone and others are foam and fabric. (Photo by Joseph Prezioso/AFP Photo)

In this April 2, 2015 photo, dog owner Laura Aquilina strolls with her two year old Rottweiler Brutus, who was recently fitted with prosthetics on all four paws, and is currently learning to use them, near Aquilina's home in Loveland, Colo. Brutus lost all four paws to frostbite as a puppy while under care of a breeder, and Aquilina began caring for him about a year ago. (Photo by Brennan Linsley/AP Photo)

Ecuadorian indigenous people celebrate the festival of the moon or Kulla Raymi, in Quito, Ecuador, 21 September 2021. A circle on the ground made up of fruits and inside the Andean symbol of the chacana, multinational geometric flags and a cross that symbolizes the four cardinal points, were the setting in which the festival of the moon, the Kulla, was commemorated this Tuesday. Raymi, on a hill in Quito. It is one of the four most significant festivities of the Andean agroecological calendar, which commemorates the beginning of life and exalts women as the maximum representation of fertility. (Photo by Jose Jacome/EPA/EFE)

Four men dressed as zombies participate in a Zombie Walk procession in the streets of Paris October 12, 2013. (Photo by Benoit Tessier/Reuters)

The nearly four-week-old Tapir cub bathes on June 28, 2016 in Gondwanaland at the zoo in Leipzig, Saxony. (Photo by Jan Woitas/DPA)

Four-month-old fox cubs squaring up to each other in Walthamstow, England on August 7, 2015. (Photo by Greg Morgan/Barcroft Media)

Valarie Allman of Team United States competes in the Women's Discus qualification on day four of the World Athletics Championships Oregon22 at Hayward Field on July 18, 2022 in Eugene, Oregon. (Photo by Pawel Kopczynski/Reuters)