“Contrails (short for “condensation trails”) or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets or, if the air is cold enough, tiny ice crystals”. – Wikipedia

Photo: An airplane leaves a vapor trail as it flies in front of he moon on January 17, 2007 above Hanover, Germany. (Photo by Alexander Hassenstein/Getty Images)

Australian actress Joy Smithers poses beside a poster featuring Australian cricketer Brett Lee during the official launch of the AceStar underwear range at Pink Salt on August 19, 2008 in Sydney, Australia. (Photo by Mike Flokis/Getty Images)

Winner of the Sandow bodybuilding competition, Mr. Murray. (Photo by Reinhold Thiele/Thiele/Getty Images). Circa 1905

Chinese women run with a ball on a snow covered field in Shenyang in China's northeastern Liaoning province during International Women's Day on March 8, 2018. International Women's Day is celebrated on March 8 every year and commemorates the movement for women's rights. (Photo by AFP Photo/Stringer)

Dancers learn choreography they will need to perform as part of an open audition for the 2022 Radio City Rockettes at Radio City Music Hall in New York, New York, USA, 18 April 2022. The open auditions, the first being held since the start of the coronavirus pandemic, were expected to draw nearly 900 dancers competing for one of the few open spots in the 2022 Christmas Spectacular Starring the Radio City Rockettes, a long running holiday show. (Photo by Justin Lane/EPA/EFE)

Passengers take photos at a wildfire while traveling on a train in Zamora, Spain, Monday, July 18, 2022. When Francisco Seoane's train unexpectedly stopped in Spanish countryside that was being engulfed by a wildfire, he and other passengers got a fright when they looked out at flames encroaching on both sides of the track. The Spaniard told The Associated Press it was scary to see how quickly the fire spread. Video of the unscheduled – and unnerving – stop shows about a dozen passengers in Seoane's railcar appearing alarmed as they look out of the windows Monday. (Photo by Francisco Seoane Perez/AP Photo)

A large teddy bear, used to enforce social distancing, is pictured sitting at a cafe in Pristina on July 23, 2020, as Kosovo authorities announce new measures to fight against the resurgence of the COVID-19, the novel coronavirus. (Photo by Armend Nimani/AFP Photo)

A model presents a creation from the LaQuan Smith Fall and Winter '23 collection at the Rainbow Room during Fashion Week in New York City, New York, U.S., February 13, 2023. (Photo by Caitlin Ochs/Reuters)