A festival goer uses a hula hoop, as revelers gather ahead of this weekends Glastonbury Festival of Music and Performing Arts on Worthy Farm in Somerset, southwest England, on June 25, 2014. US metal giants Metallica will play this year's coveted Saturday night headline spot at Britain's Glastonbury festival, organisers announced Thursday. It will be the “Master of Puppets” four-piece's first appearance at the legendary festival, held in south west England, following on from The Rolling Stones' Worthy Farm debut last year. (Photo by Leon Neal/AFP Photo)

“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)

Dancers wait in the wings before performing in a full-dress rehearsal at the Moulin Rouge in Paris on September 8, 2021, two days ahead of the reopening of the cabaret following an 18-month closure amid the COVID-19 pandemic. Closed for a year and a half due to the pandemic, the Moulin Rouge and Le Lido, emblems of the crazy Parisian nights since 1889, are finally reopening. (Photo by Christophe Archambault/AFP Photo)

New Zealand Defence Force personal perform a haka during Te Rau Aroha, an evening to commemorate Maori service in the New Zealand Armed Forces on February 05, 2020 in Waitangi, New Zealand. The Waitangi Day national holiday celebrates the signing of the treaty of Waitangi on February 6, 1840 by Maori chiefs and the British Crown, that granted the Maori people the rights of British Citizens and ownership of their lands and other properties. (Photo by Fiona Goodall/Getty Images)

Women perform the Chilean protest song about rape culture, “A rapist in your path”, during a protest march marking International Women's Day, in Lima, Peru. Saturday, March 7, 2020. March 8th has been sponsored by the United Nations since 1975 as International Women's Day, celebrating women's achievements and aiming to further their rights. Marches and protests are held across the globe with calls for a more gender-balanced world to mark the day. (Photo by Rodrigo Abd/AP Photo)

Revelers celebrate New Years Eve in socially distanced pods at Times Square on December 31, 2020, in New York City. On average, about one million revelers are drawn to the Crossroads of the World to watch performances and celebrate the New Year. This year a limited live audience of about 40 first responders and essential workers will be allowed to watch the New Years' ball drop from a secure area in Times Square. (Photo by David Dee Delgado/Getty Images)

A man and a woman jump over a bonfire during Ivan Kupala Day celebrations held by the Belarusian State Museum of Folk Architecture and Rural Lifestyle in the village of Ozertso near Minsk, Belarus on July 4, 2020. Ivan Kupala Day, also known as Ivana-Kupala or Kupala Night, is a traditional pagan holiday celebrated in eastern Slavic cultures. Various rituals are traditionally performed on Kupala Night, including making flower wreaths, fortune-telling, jumping over bonfires, and burning a wheel-like effigy symbolizing the sun. (Photo by Natalia Fedosenko/TASS)

Performers on boats take part in the Qintong Boat Festival at Qin Lake National Wetland Park on April 6, 2019 in Taizhou, Jiangsu Province of China. The boat festival is held around the Qingming Festival every year, and up to 10,000 participants from nearby villages and towns, with more than 500 boats, took part in the event this year. (Photo by Tang Dehong/VCG via Getty Images)