“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)

It’s time to start watching for Comet PANSTARRS, one of two comets to get excited about in 2013. Photo: This image provided by NASA shoaws the comet PANSTARRS as seen from Mount Dale, Western Australia on March 5, 2013. According to NASA on March 10, it will make its closest approach to the sun about 28 million miles (45 million kilometers) away. As it continues its nightly trek across the sky, the comet may get lost in the sun's glare but should return and be visible to the naked eye by March 12. (Photo by AP Photo/NASA)

An extreme Vespa enthusiast rides his bike after attending weekend festival for extreme Vespas in Semarang, Central Java, Indonesia, July 22, 2018. Every year, Indonesians from teens and granddads, to mechanics and students, gather in eastern Java to celebrate their love of the iconic Italian Vespa scooter. (Photo by Darren Whiteside/Reuters)

In Weronika Gęsicka’s unsettling images, American archive photography gets distorted into scenes that are both nightmarish yet somehow entirely plausible. Gęsicka is a guest artist at the Circulations festival for young European photographers, Paris, until 5 March. Here: “Untitled #5”. (Photo by Weronika Gęsicka/The Guardian)

A Ukrainian serviceman walks an empty street in the front line city of Bakhmut, in Donetsk region, Ukraine on February 25, 2023. (Photo by Serhii Nuzhnenko/Radio Free Europe/Radio Liberty)

Mary Jose Cristerna, a Mexican known as The Vampire Woman, poses for the public to take portraits of her during the annual Venezuela Tattoo International Expo in Caracas, Venezuela, Thursday, January 29, 2015. Tattoo artists from around the world are gathering for the four-day event that also includes under the skin implants and body piercing. (Photo by Ariana Cubillos/AP Photo)

Britain's Red Arrows airplane display team perform during D-Day commemorations in Portsmouth in southern England on June 5, 2014. Several hundred surviving veterans of the 1944 D-Day landings are commemorating the 70th anniversary of the mission on both sides of the English channel. (Photo by Carl Court/AFP Photo)