A striking video of the contrail was taken from another airplane while the Boeing 787 was flying at 33,000 feet above the east coast of Russia.
The Chemtrails conspiracy theory is among the most supported on Earth and counted the late pop legend Prince among its high-profile supporters.
At its most strange extreme, it is believed the contrails which form behind jet airplane are in fact streams of hazardous toxic "mind-control" chemicals, which water down before they reach the ground, leaving a gas we take in that keeps the basic population in check.
But there are a growing number of chemtrail followers, who claim the conspiracy is in fact a secret worldwide plot to alter Earth's climate in the hope it will reverse the results of environment modification.
People who have actually seen the video online have published their reactions.
One poster using the name Celsius Increasing said: "Condensation trails do not extend for miles throughout the sky, and are hardly ever longer than a few hundred feet in length.
" The tracks that continue for many miles are something else, and I for one, want to understand exactly what the hell is being sprayed over our heads, and why."
Another wit the user name JR included: "Anybody with brains knows they are chemtrails that spread out across the sky and never dissipate.
" It's all part of the global warming program.
" Regretfully these chemicals are dangerous. Go to geoengineering.com if you wish to be informed."
Nevertheless, others rubbished the conspiracy theorist's claims.
One calling themselves Old Ollie stated: "Seriously, chemtrails? Do you buy your tinfoil hats ready-to-wear, or do you make them yourselves?"
While another called McLowe stated: "Chemtrail ... you're Funny! It's called water vapour."
The individual who filmed contrail was also level headed about exactly what they saw, composing: "This contrail looks dark against the increasing sun.
He stated the routes were the result of hot exhaust mixing with cold wet air.