A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)

Revelers throw colored corn starch into the air as they celebrate the 2015 Holi (Festival of Colors) at the Krishna Temple in Spanish Fork, Utah on Saturday, March 28, 2015. (Photo by Rick Bowmer/AP Photo)

A reveller walks through the streets in the early hours during traditional May Day celebrations in Oxford, Britain, May 1, 2015. (Photo by Dylan Martinez/Reuters)

Revellers dressed in mock military garb take part in “Els Enfarinats” food-battle in the southeastern Spanish town of Ibi on December 28, 2022. (Photo by Jaime Reina/AFP Photo)

A reveller smeared in vermilion powder celebrates the Bisket Jatra Festival in Thimi in the Bhaktapur District on the outskirts of Kathmandu on April 15, 2023. (Photo by Prakash Mathema/AFP Photo)

Revellers hit the booze cruise in the Croatian port city of Split on August 11, 2023. The hot new party town for Brits. Boat Party booze cruise with Split after dark. (Photo by Darren Fletcher)

Revelers run through the festival grounds to see the next show at the Governors Ball music festival at Corona Park in the Queens borough of New York City, U.S., June 9, 2024. (Photo by Cheney Orr/Reuters)

“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)