A man carrying vegetables is stopped by police at a barricade on a road during a 21-day nationwide lockdown to limit the spreading of coronavirus disease (COVID-19) in Chennai, India, March 25, 2020. (Photo by P. Ravikumar/Reuters)

A robot, developed by start-up firm Asimov Robotics, holds a tray with face masks and sanitizer after the two robots were launched to spread awareness about the coronavirus, in Kochi, India, March 17, 2020. (Photo by Sivaram V/Reuters)

People wearing face masks to prevent the spread of coronavirus gather in a discotheque in Madrid, Spain, early Saturday, July 25, 2020. Nightlife is becoming the new target of Spanish authorities attempting to contain a spike in coronavirus infections since the country ended a lockdown. The Catalonia regional government has shut nightlife venues in Barcelona, and on Friday officials in Madrid said they were considering a similar step. (Photo by Manu Fernandez/AP Photo)

Girls from the Miao ethnic group dress up in ethnic costumes to celebrate the traditional Lusheng Festival on December 12, 2022 in Congjiang County, Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou Province of China. (Photo by Mo Xiaoshu/VCG via Getty Images)

Newlyweds celebrate their wedding surrounded by friends on Red Square in Moscow on November 11, 2020, amid the ongoing coronavirus disease pandemic. (Photo by Natalia Kolesnikova/AFP Photo)

A girl poses in antlers ahead of a curfew on pub in Nottingham, a city in central England’s Midlands region on September 21, 2020 as Freshers' Week got underway. Revellers were also pictured out in Birmingham, which was plunged into a local lockdown amid a surge in coronavirus cases. (Photo by Ashley Kirk/The Sun)

“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)

Social activists working for the rights of sеx workers celebrate with colour powder during the International Sеx Workers' Rights Day in Kolkata on March 3, 2020. (Photo by Dibyangshu Sarkar/AFP Photo)