A staff of the Beijing 2022 Winter Olympic Games holds a placard reading “Mask on” as USA's players react after their defeat in the women's gold medal match of the Beijing 2022 Winter Olympic Games ice hockey competition between Canada and USA, at the Wukesong Sports Centre in Beijing on February 17, 2022. (Photo by Kirill Kudryavtsev/AFP 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 May 17, 2017 photo, cowboy cook Odair Batista carries a case with food in Corumba, the Pantanal wetlands of Mato Grosso do Sul state, Brazil. Dressed with leather chaps on top of their jeans, stetson hats and a machete attached to their waists, before setting off, the men finish their breakfast with Terere, an herbal “mate” beverage served ice cold in an ox drinking horn. (Photo by Eraldo Peres/AP Photo)

Lisa Yu crawls through a mud pit under low slung barbed wire as she competes in The Tough Bloke Challenge on March 4, 2012 in Melbourne, Australia. The Tough Bloke Challenge is one of the most gruelling adventure runs in Australia consisting of 18 obstacles over a 6 km cross-country course laden with thick mud-pits and ice-cold water crossings. (Photo by Scott Barbour/Getty Images)

This picture taken on January 25, 2015 shows a participant taking part in an ice water challenge in Zhangjiajie, central China's Hunan province. Participants were required to stay in an ice pond, holding an ice block while eating ice-cream with an electric fan blowing at them. (Photo by AFP Photo/Stringer)

Actors perform during the ice sculptures festival “Ice Moscow” in Moscow, Russia, 06 January 2025. (Photo by Yuri Kochetkov/EPA/EFE)

“A Little Monkey on the Cliff”. “A cold front hit the Nagano prefecture. I saw a little monkey enduring the cold in Jigokudani Monkey Park. This little monkey is really cute”. (Photo by Hidetoshi Ogata/Smithsonian Photo Contest)

Asya Seker of NSW competes in the Rhythmic Gymnastics during the 2024 Australian Gymnastics Championships at Gold Coast Sports and Leisure Centre on May 20, 2024 in Gold Coast, Australia. (Photo by Matt Roberts/Getty Images)