Desmond Boylan, a photographer who covered war and conflict across the world before dedicating his life to documenting the daily joys and tribulations of life in Cuba for Reuters and The Associated Press, died suddenly while on assignment on Saturday, December 29, 2018 afternoon in Havana. Here: Cuban President takes a glass during a ceremony in the Oporto Bourse where he and other Ibero-American leaders were made members of the Port Wine Brotherhood in Portugal, October 1998. (Photo by Desmond Boylan/Reuters)

A solar-powered plane takes off from Jiangbei International Airport in southwest China's Chongqing Municipality, Tuesday, April 21, 2015. The Solar Impulse 2 departed Chongqing on Tuesday for a 1190-kilometer (642-mile) flight to the city of Nanjing in eastern China, the sixth leg of its around-the-world flight. (Photo by Chinatopix via AP Photo)

Less than lady like behaviour on Ladies' Day at Epsom, England on June 2, 2017. Ladies' Day is traditionally held on the first Friday of June, a multitude of ladies and gents head to Epsom Downs Racecourse to experience a day full of high octane racing, music, glamour and fashion. (Photo by Peter Dench/Getty Images Reportage)

Drinking from a helmet at a graduation ceremony held by the Military University of the Russian Defence Ministry at Moscow's Victory Park in Moscow, Russia on June 15, 2019. (Photo by Gavriil Grigorov/TASS)

Miesha Tate, UFC women's bantaweight shows the media how to fight during a UFC press conference at Akasaka Garden City on August 26, 2014 in Tokyo, Japan. (Photo by Atsushi Tomura/Getty Images)

Three secondary schoolboys smoking an illicit cigarette in Hyde Park, London. (Photo by Evening Standard/Getty Images). May 1972

“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)