This picture taken on June 25, 2019 shows couples wait for their turn for their pre-wedding photo shoot at the Love Story in Rome Studio in Beijing. Increasingly elaborate pre-wedding photos are a booming industry in China, as young couples spend time and cash lining up glamorous photo shoots to display on their big day. (Photo by Fred Dufour/AFP Photo)

A Hezbollah supporter fires a rocket-propelled grenade in the air to celebrate the arrival of Iranian fuel tankers to Lebanon, in the eastern town of Baalbek, Lebanon, Thursday, September 16, 2021. The delivery violates US sanctions imposed on Tehran after former President Donald Trump pulled America out of a nuclear deal between Iran and world powers three years ago. (Photo by Bilal Hussein/AP Photo)

Members of the Territorial Defence Forces and volunteers place anti-tank obstacles at a checkpoint, as Russia's invasion of Ukraine continues, at the Independence Square in central Kyiv, Ukraine on March 3, 2022. (Photo by Valentyn Ogirenko/Reuters)

TikTok chef Abir El Saghir prepares a pastry dish at her kitchen in Jeb Jennin, west Bekaa, Lebanon on June 30, 2022. (Photo by Issam Abdallah/Reuters)

Revelers take part in the Theatre Bizarre festival, a Halloween celebration that is returning in person for the first time since the COVID-19 pandemic, in Detroit, Michigan, U.S., October 14, 2022. (Photo by Dieu-Nalio Chery/Reuters)

Panda keepers hold cubs while posing for photos ahead of the new year at the Chengdu Research Base of Giant Panda Breeding in Chengdu, China's southwestern Sichuan province on December 29, 2022. (Photo by AFP Photo/China Stringer Network)

Jessie Jo Stark and Bella Hadid attend Chrome Hearts X Bella Hadid Collaboration Launch as part of Paris Fashion Week at Chrome Hearts on March 4, 2017 in Paris, France. (Photo by Julien M. Hekimian/Getty Images for Chrome Hearts)

“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)