“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)

“The Queen” painted fibreglass by artist John Humphreys is displayed backdropped by other works which feature in this year's Summer Exhibition on it's 250th year at the Royal Academy of Arts in London, Tuesday, June 5, 2018. The Summer Exhibition has been held since 1769, with around 1300 works on display this year and most of them available for purchase. It runs from June 12 until August 19. (Photo by Matt Dunham/AP Photo)

A herdsman stands on the back of a grey bull during a ceremony of driving sheep from their winter habitat to their summer pasture in the puszta or Hungarian steppe of Hortobagy, 183 kms east of Budapest, Hungary, 23 April 2016. Sheep are traditionally driven to their summer pasture at around St. George's Day in the Hortobagy region, because livestock breeding people traditionally consider St. George's Day the beginning of spring. (Photo by Zsolt Czegledi/EPA)

Miranda Kerr poses at the David Jones Spring/Summer fashion preview on Burke Street on August 10, 2011 in Melbourne, Australia. (Photo by Lucas Dawson)

Antonina Petkovic walks the runway during the Jean Paul Gaultier Spring Summer 2016 show as part of Paris Fashion Week on January 27, 2016 in Paris, France. (Photo by Pascal Le Segretain/Getty Images)

A model presents a creation from the Tom Ford Spring/Summer 2015 collection during London Fashion Week September 15, 2014. (Photo by Suzanne Plunkett/Reuters)

A model wears a creation for Anthony Vaccarello's Spring/Summer 2015 ready-to-wear fashion collection, presented in Paris, Tuesday, September 23, 2014. (Photo by Jacques Brinon/AP Photo)