British singer Rita Ora arrives for the Echo Award at Messe Berlin on April 12, 2018 in Berlin, Germany. (Photo by Andreas Rentz/Getty Images)

Young category winner. Great autumn morning by Fabian Dalpiaz. (Photo by Fabian Dalpiaz/2018 Astronomy Photographer of the Year)

A model present a creation by Marina Hoermanseder during the Berlin Fashion Week Autumn/Winter 2019/20 in Berlin, Germany, January 17, 2019. (Photo by Fabrizio Bensch/Reuters)

Captain George Ash lies on his back as he prepares to shoot the bowl from the clay pipe held between a blindfolded corporal's teeth. (Photo by Fox Photos/Getty Images). 18th April 1932

“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)

Emma Watson poses at the winners boards at the Sony Ericsson Empire Film Awards at the Grosvenor House Hotel on March 9, 2008 in London England. (Photo by Dan Kitwood/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)

Models showcase Valentine's Day underwear celebrating the results of a recent survey revealing that men find the lingerie, boxer shorts and vests, the biggest turn on ahead of February 14 Valentine celebrations, at Waterloo on February 2, 2006 in London, England. (Photo by Gareth Cattermole/Getty Images)