“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)

Models pose in creations from the Salinas collection during Sao Paulo Fashion Week in Sao Paulo, Brazil, Wednesday, April 25, 2018. (Photo by Andre Penner/AP Photo)

Mara Salvatrucha (MS) gang members show off their weapons in the Las Victorias district of San Salvador. In March 2012, the two largest gangs in El Salvador - the Mara Salvatrucha (MS) and the Barrio 18 (M18) - agreed on a truce following secret negotiations between gang leaders in prison which were mediated by a bishop and a former rebel leader. It is unclear whether the decision was the idea of the gangs themselves or whether they were encouraged by the government. (Photo by Adam Hinton)

Italian artist Maurizio Cattelan poses with his creation “Him” (2001) prior to the opening of the exhibition “Not Afraid of Love” at the Hotel de la Monnaie in Paris, France, October 17, 2016. From October 21, 2016 to January 8, 2017, “Not Afraid of Love”, curated by Chiara Parisi, director of Cultural Programs, sets Maurizio Cattelan’s “comeback at work” in one of the most beautiful Palaces on the river Seine. (Photo by Philippe Wojazer/Reuters)

Models wear creations from the Ronaldo Fraga collection during the Sao Paulo Fashion Week in Sao Paulo, Brazil, Monday, April 25, 2016. (Photo by Andre Penner/AP Photo)

British model Demi Rose leaving Bob Bob Ricard on November 20, 2017 in London, England. (Photo by Splash News and Pictures)

Model Bella Hadid is seen on June 9, 2017 in Paris, France. (Photo by Marc Piasecki/GC Images)

Members of the Wasteland Warriors from the movie “MadMax” pose during the Wacken Open Air festival on August 4, 2016 in Wacken, Germany. Wacken is a village in northern Germany with a population of 1,800 that has hosted the annual festival, which attracts heavy metal fans from around the world, since 1990. (Photo by Alexander Koerner/Getty Images)