General view of the screens in Hyde Park to showing the Royal Wedding on April 29, 2011 in London, England. The marriage of Prince William, the second in line to the British throne, to Catherine Middleton is being held in London today. The Archbishop of Canterbury conducted the service which was attended by 1900 guests, including foreign Royal family members and heads of state. Thousands of well-wishers from around the world have also flocked to London to witness the spectacle and pageantry of the Royal Wedding and street parties are being held throughout the UK. (Photo by Tom Dulat/Getty Images)

“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)

Revellers take part in the Children's Day parade of the Notting Hill Carnival in London, Britain, 28 August 2016. The street festival celebrates this year its 52nd anniversary and more than a million people are expected to attend on 28 and 29 August. (Photo by Will Oliver/EPA)

An Afghan girl stand in the doorway of her home in Kabul, Afghanistan, Monday, March 29, 2021. (Photo by Rahmat Gul/AP Photo)

Greek actress Xanthi Georgiou, playing the role of the High Priestess, lights up the torch during the flame lighting ceremony for the Beijing 2022 Winter Olympics at the Ancient Olympia archeological site, birthplace of the ancient Olympics in southern Greece on October 18, 2021. The Olympic flame will once again be lit in an empty stadium on Ovtober 18, 2021, as it starts its truncated journey to Beijing for the Winter Games in February. Like the ceremony in March 2020 to light the flame for Tokyo, and like those Games, which were put back a year, Monday's ceremony is a victim of coronavirus restrictions. (Photo by Aris Messinis/AFP Photo)

American rapper Saweetie performs at the European MTV Awards in Budapest, Hungary, Sunday, November 14, 2021. (Photo by Vianney Le Caer/Invision/AP Photo)

Pittsburgh Steelers outside linebacker T.J. Watt (90) is introduced before an NFL football game against the Detroit Lions in Pittsburgh, Sunday, November 14, 2021. (Photo by Don Wright/AP Photo)

In this Saturday, August 16, 2014 photo, Mandy Stokes stands with her daughter Molly Kate Stokes next to a large alligator weighing 1011.5 pounds measuring 15-feet long is pictured in Thomaston, Ala. The alligator was caught in the Alabama River near Camden, Ala., by Mandy Stokes and family. (Photo by Sharon Steinmann/AP Photo/Al.com)