“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 February 4, 2016 picture a masked participant of the traditional carnival parade poses in the streets of the village of Kippel in the Loetschental valley, southwestern part of Switzerland. During this sinister carnival, participants wearing wooden masks and animal furs, crowd the streets of the villages to scare the people. (Photo by Dominic Steinmann/Keystone via AP Photo)

In this handout image provided by Parks Australia, thousands of red crabs are seen walking in a drain on November 23, 2021 in Christmas Island. The annual migration of red crabs begins with first rains of the wet season on Christmas Island, usually around October or November. Millions of the red crabs make their way across the island to the ocean to mate and spawn. (Photo by Parks Australia via Getty Images)

Costumed revellers walk in the streets of Lucerne during the annual carnival parade on Rose Monday March 3, 2014. (Photo by Sigi Tischler/AP Photo/Keystone)

Canoeists are framed by the tail of a breaching whale in Antarctica in April 2023. The photographer, from California, writes: “It was probably a once-in-a-lifetime moment”. (Photo by Jiahong Zeng/Solent News)

A woman reacts after she mades a wreath of flowers during the celebrations of the Kupala night in Pyrohiv, near Kiev, on July 6, 2021. During the celebration, an ancient slavic ritual related to the summer solstice, people wear wreaths, jump over fires and bathe naked in rivers and lakes. (Photo by Sergei Supinsky/AFP Photo)

A saddle-billed stork stands in the grassland at the Nairobi National Park near Nairobi, Kenya January 23, 2017. (Photo by Thomas Mukoya/Reuters)

Geisha women parade down the street to Asakusa Shrine in the compound of Sensoji Temple Friday, May 19, 2017, in Tokyo prior to the annual Sanja Festival, one of the three major festivals in Tokyo. (Photo by Eugene Hoshiko/AP Photo)