A closer look
Contrails left behind by high-altitude jet airplanes are not chemical mind-control sprays, but simply artificial clouds created by hot engine exhaust instantly freezing in the frigid upper atmosphere. The water vapor condenses into ice crystals, leaving those fluffy white streaks across the sky that inevitably trigger internet conspiracy theorists. Depending on the humidity at thirty thousand feet, these trails can vanish in seconds or linger for hours, acting exactly like regular cirrus clouds. It is somewhat tragic that a basic, beautiful display of atmospheric thermodynamics has been hijacked by people who genuinely believe commercial airlines are secretly dosing the populace to make them buy more streaming subscriptions
