A British Spitfire and an American P-51 Mustang from Ultimate Warbird Flights take to the Northamptonshire on August 14, 2020 skies to mark the 75th anniversary of VJ Day. (Photo by Richard Pohle/The Times)

Joshua Patino stands on a ladder to put finishing touches on a giant dinosaur exhibit at PAX East in the Boston Convention and Expo Center, Thursday, April 21, 2016, in Boston. PAX East, an annual celebration of gaming culture, is expected to draw tens of thousands of visitors Friday through Sunday. It's a place where serious gamers can preview unreleased video games and devices, compete in tournaments, hear live music and meet others for whom gaming is a way of life. (Photo by Elise Amendola/AP Photo)

“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)

In this handout photograph received from the Delhi Police at the scene of the incident, an Indian schoolboy is confronted by a white tiger inside its enclosure at the Delhi Zoo in New Delhi on September 23, 2014. A white tiger on September 23 attacked and killed a schoolboy who appeared to have jumped or fallen into its enclosure at the zoo in the Indian capital, witnesses said. (Photo by AFP Photo/Delhi Police)

Ricky Rebel attends the 62nd Annual GRAMMY Awards at Staples Center on January 26, 2020 in Los Angeles, California. (Photo by Mike Blake/Reuters)

Storm clouds blanket the sky over Great American Ball Park as Starlin Castro #13 of the Chicago Cubs fields a ground ball in the fifth inning against the Cincinnati Reds as on July 7, 2014 in Cincinnati, Ohio. (Photo by Jamie Sabau/Getty Images)

A Kashmiri Muslim woman balances on a water pipe before collecting water at Dasilpora village on March 22, 2018. World Water Day is held annually on 22 March as a means of focusing attention on the importance of freshwater and advocating for the sustainable management of freshwater resources. (Photo by Tauseef Mustafa/AFP Photo)

Performers re-enact the 1947 massacre of Taiwanese intellectuals by mainland China's Nationalists troops during the inauguration ceremony of Taiwan's President Tsai Ing-wen in Taipei, Taiwan, Friday, May 20, 2016. Taiwan inaugurated Tsai as its first female president on Friday, returning the pro-independence Democratic Progressive Party to power amid new concerns over increasingly fractious relations with Beijing and a flagging economy. (Photo by Chiang Ying-ying/AP Photo)