“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)

Bella Hadid attends “The Unknown Girl (La Fille Inconnue)” Premiere during the 69th annual Cannes Film Festival at the Palais des Festivals on May 18, 2016 in Cannes, France. (Photo by Alberto Pizzoli/AFP Photo)

Vivian Odhiambo, 24, frys samosas in the trading centre of Kogelo, west of Kenya's capital Nairobi, July 14, 2015. Odhiambo said, “Obama is our hero and we wait to welcome him back home again. We in Kogelo have witnessed general growth and we are proud of being associated with the Obamas”, she added. As U.S. President Barack Obama visits Kenya, a personal connection to his father's birthplace of Kogelo dominates a trip that Kenyans view as a native son returning home. Residents from a herdsman to a housewife share their views on what Obama has achieved and what they would like to see next. (Photo by Thomas Mukoya/Reuters)

Russia' s Tiffani Zagorski and Russia' s Jonathan Guerreiro compete in the ice dance free dance of the figure skating event during the Pyeongchang 2018 Winter Olympic Games at the Gangneung Ice Arena in Gangneung on February 20, 2018. (Photo by Lucy Nicholson/Reuters)

Even upside down, a stereophonic turntable continues to play and hold the interest of Helen Sorowitz, a visitor to the New York High Fidelity Show in New York, September 9, 1960. (Photo by Ruben Goldberg/AP Photo)

Sister Kate and Sister Claire pose on the beach to promote the documentary film “Breaking Habits?” at the Cannes Film Festival on May 09, 2018 in Cannes, France. (Photo by Regis Duvignau/Reuters)

A woman holds up what the Chris Steaks & Burgers restaurant says is Thailand's biggest burger weighing more than 6 kilograms, before a competition held to eat it at the restaurant in Bangkok, Thailand, October 11, 2019. Chris Steaks and Burgers is offering a 10,000 baht ($330) prize for anyone who can finish the mammoth snack in nine minutes – one baht for every calorie. (Photo by Jiraporn Kuhakan/Reuters)

A cat stretches on top of dried seafood in a shop in the Sheung Wan district of Hong Kong on August 7, 2020. International Cat Day, celebrated on August 8, is a day to raise awareness for cats and learn about ways to help and protect them. (Photo by Isaac Lawrence/AFP Photo)