A man bundled up for the cold weather carries a dog in his jacket while walking along the waterfront in New Westminster, British Columbia, Tuesday, December 28, 2021. Environment Canada has issued an arctic outflow warning for Metro Vancouver and the south coast with well below normal temperatures forecast for the region. (Photo by Darryl Dyck/The Canadian Press via AP Photo)

A monument to the character of Darth Vader from "Star Wars", which was rebuilt from a statue of Soviet state founder Vladimir Lenin, is seen in Odessa, Ukraine, October 23, 2015. The Internet Party of Ukraine's main candidate, a person named for the legendary "Star Wars" villain Darth Vader, campaigned in Odessa, cruising through town on a black van to the sound of Imperial March from "Star Wars" saga. (Photo by Yevgeny Volokin/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)

A pheasant stands in snow near Dulverton on January 30, 2012 on Exmoor, England. After unseasonably mild winter weather, some parts of the UK woke to a covering of snow as a cold spell of weather sets in, with forecasters warning temperatures are set to plunge as the week progresses. (Photo by Matt Cardy/Getty Images)

A Chinese girl touches the gun of a relievo featuring Chinese soldiers fighting with Japanese troops during World War II at an exhibition at the Anti-Japan War Museum to mark the 60th Anniversary of the Victory of the Chinese People's War of Resistance Against Japan on August 18, 2005 in Beijing, China. (Photo by Cancan Chu/Getty Images)

Five hundred replicas of the Stormtrooper characters from "Star Wars" are placed on the steps at the Juyongguan section of the Great Wall of China during a promotional event for "Star Wars: The Force Awakens" film, on the outskirts of Beijing, China, October 20, 2015. (Photo by Jason Lee/Reuters)

Mil Mi-8 combat helicopter flies over Moscow, Russia on May 7, 2019 during the dress rehearsal of a Victory Day air show marking the 74th anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II. (Photo by Sergei Savostyanov/TASS)

Russian Boxing Federation lifts a portrait of late Soviet leader Joseph Stalin with a hot air balloon, close to city of Belogorsk outside Simferopol, Crimea, on May 11, 2020, to mark the 75th anniversary of the end of World War II also called the Great Patriotic War, amid the coronavirus (COVID) pandemic. (Photo by AFP Photo/Stringer)