A Facebook post which claims that a number of long white lines of vapour in the sky are “chemtrails” is inaccurate.
The post includes a photograph with the caption “I’ve got a beautiful feeling those are chemtrails not clouds in my way.”
The hashtag #Chemtrails has also been trending on Twitter in recent days.
“Chemtrails” refers to a conspiracy theory which claims that these white lines in the sky are evidence of a plot to either spread poison or control the weather by spraying chemicals from aircraft.
As we’ve written before, these lines are not poisons or weather-controlling materials being released by aircraft. They are actually condensation trails, or contrails.
Contrails are long thin lines of cloud which are formed when water vapour produced at high altitudes by aeroplane engines freezes as it is released into the cold air surrounding the aeroplane.
The frozen vapour leaves a trail of tiny ice crystals behind the aeroplane’s engines which, depending on the humidity of the air, either change directly from a solid to a gas—and become invisible after a few minutes, or remain as water droplets or ice crystals, creating the white lines often seen in the sky.
These trails can remain in the sky for several hours, which explains why this particular Facebook image shows the trails despite there being no aeroplanes in sight.
Image courtesy of William Hook.