Two F-15E Strike Eagles wait to receive fuel from a KC-135R Stratotanker during exercise Red Flag 15-1 on their way to Nellis Air Force Base, Nev., Jauary 23, 2015. The F-15s are assigned to the 4th Fighter Wing. U.S. (Photo by Airman 1st Class Aaron J. Jenne/Reuters)

Monks attend a prayer service for blessing at the Gandan Temple in Lhasa, capital of southwest China's Tibet Autonomous Region, February 5, 2020. Tibetan Buddhist temples held prayer services to support novel coronavirus-infected areas in China. The monks here were also organized to donate money to help fight against the epidemic. (Photo by Chogo/Xinhua News Agency)

A reveller reacts amid a “flour war” during the “Ash Monday” celebrations, a traditional festivity marking the end of the carnival season and the start of the 40-day Lent period until the Orthodox Easter, in the port town of Galaxidi, Greece, on March 11, 2019. (Photo by Aris Messinis/AFP Photo)

Firefighters work to put out flames during a wildfire in Sokcho, South Korea, April 5, 2019. South Korea grappled with the massive blaze that roared through forests and cities along the eastern coast, declaring a national emergency and mobilizing all available resources to bring the inferno under control. (Photo by Yonhap via Reuters)

N.C. Dezendorf, wife of the general manager of the Electro-Motive division of General Motors, christens the new lightweight “Aerotrain” at the company's locomotive works in La Grange, Ill. on August 22, 1955. (Photo by Edward Kitch/AP Photo)

A female sniper of the Syrian Democratic Forces (SDF) monitors the area during a celebration at the iconic Al- Naim square in Raqa on October 19, 2017, after retaking the city from Islamic State (IS) group fighters. The SDF fighters flushed jihadist holdouts from Raqa' s main hospital and municipal stadium, wrapping up a more than four- month offensive against what used to be the inner sanctum of IS' s self- proclaimed “caliphate”. (Photo by Bulent Kilic/AFP Photo)

Cory Ritz braces himself as a wave bursts onto a pier at the Boynton Beach inlet on August 25, 2011 in Boynton Beach, Florida. Hurricane Irene is moving over the Bahamas and could still be a major storm as it approaches the North Carolina coast the morning of August 27. (Photo by Joe Raedle/Getty Images)

A Lockheed Super Constellation “Super Connie” lands during the Air14 airshow at the airport in Payerne August 30, 2014. The Swiss Air Force celebrates their 100th anniversary with the biggest airshow in Europe this year. (Photo by Ruben Sprich/Reuters)