“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)

Impala pictured in the Kruger National Park on December 7, 2007 in Mpumalanga, South Africa. (Photo by Warren Little/Getty Images)

These snaps capture true winter wonderlands – as Mother Nature's icy grip takes hold of America's National Parks. From snow-capped mountains in Yosemite to an icy still Glacier Bay, the incredible images show their beauty is year round. In other breath-taking shots crisp frost lines the paths through Great Smokey Mountains and Crater Lake has had more than a dusting of snow. Here: Apostle Island National Lakeshore Park in Wisconsin. (Photo by U.S. Department of the Interior/Cater News)

A winter swimmer, wearing a Santa Claus hat to celebrate the upcoming Christmas, reacts as he plays on a frozen lake at a park in Shenyang, Liaoning province, December 22, 2014. The characters on the hat read: “Shenyang Winter Swimming”. (Photo by Reuters/Stringer)

Models present creations “2033 (teens)” by Belarusian designer Anastasiya Kutepova during a show at the festival and contest Fashion Mill, amid the coronavirus disease (COVID-19) outbreak, in Minsk, Belarus on June 30, 2020. (Photo by Vasily Fedosenko/Reuters)

LONDON - JUNE 04: A piece entitled “Entrance into wood” by Elke Krystufek goes on show at The Royal Academy Summer Exhibition on June 4, 2008 in London. In it's 240th year, the exhibition displays a wide range of recent work by both established and emerging artists. 10,000 artists submitted work for selection this year. (Photo by Peter Macdiarmid/Getty Images)

Women wearing face-kini masks lie on a beach to rest in Qingdao, Shandong province, China, June 3, 2015. A pale complexion is highly prized as delicate and feminine in China while dark skin suggests tanning caused by farming the fields or other lowly, outdoor work. (Photo by Reuters/Stringer)