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That air where the condensation trail and cloud ended up can easily change directions or the area it covers with the wind in the sky, and when the sunlight hits it just right, can end up creating quite a spectacle. 
Where this mechanism was concerned, the subcommittee cautioned that the presence in engine exhaust of sufficient water to produce a condensation trail did not necessarily verify this mechanism as a cause of vapor trails.
Although ubiquitous today, condensation trails were apparently unknown until World War I.
Detractors though -- including the British bases, which have been accused of being the culprits in the past -- say the trails are merely condensation trails or contrails which form when exhaust gases from passing passenger jet engines combine with very cold, humid air at high altitude.
Detractors -- including the British bases, which have been accused of being the culprits - however say the trails are nothing more than condensation trails or contrails which form when exhaust gases from passing passenger jet engines combine with very cold, humid air at high altitude."
Many of the videos feature the "chemtrails" conspiracy theory - a belief that condensation trails left by planes deliberately eject harmful substances to modify the weather, control people, or for biological or chemical warfare.
"Chemtrails, the name given to condensation trails left by aircrafts, that some believe are chemical agents sprayed by the government, also ranked highly in both countries, as did the popular theory that the moon landings were a hoax."
The team ruled out other explanations of things that could cause these dust clouds to show up in the photographs - including optical artefacts, faint clouds in the skies of the Earth, and condensation trails of aircraft.
Until the sky appears to be, An Einsteinian equation; Or perhaps those condensation trails, Are some mad scientist's creation?
The report, ordered by Agriculture Minister Nicos Kouyialis back in February, determined that contrails (short for condensation trails) are responsible for the phenomenon observed where white trails crisscross the sky, sometimes lingering there for hours.
Contract notice: Condensation trails from biofuel/kerosene blends scoping study.
According to study published by the journal Nature Climate Change: "Aircraft condensation trails and the clouds that form from them may be causing more warming today than all the aircraft-emitted carbon dioxide that has accumulated in the atmosphere since the start of aviation."