One of my favorite conspiracy theories to debate is “chemtrails.” The factual explanations behind the puffy white lines are so fabulously simple, you’ve got to marvel at those who harbor this preposterous notion. Entertain no fear, intelligent reader, as this conspiracy can only be held by the least scientific among us. To argue with chembelievers is to feel both frustration and bewilderment manifest.
You’ll hear the battle cry of the Chemtrailers: “Wake up! Look up!” soliciting you to abandon your ability to research for the blind acceptance of anecdotal opinion. We live in a world where information is so readily accessible for anyone who chooses to pursue it. The challenge comes in vetting sources, and this seems to be the trap in to which Chemtrailers fall. They want so badly to be right about being sprayed, they will use any source available that serves their confirmation bias.
Contrails, as they’re known by the scientifically literate among us, are quite simply explained. In fact, NASA does quite a good job of expounding it:
“Contrails are clouds formed when water vapor condenses and freezes around small particles (aerosols) that exist in aircraft exhaust. Some of that water vapor comes from the air around the plane; and, some is added by the exhaust of the aircraft. The exhaust of an aircraft contains both gas (vapor) and solid particles. Both of these are important in the formation of contrails. Some elements of the exhaust gasses are not involved in contrail formation but do constitute air pollution. Emissions include carbon dioxide, water vapor, nitrogen oxides (NOx), carbon monoxide, hydrocarbons such as methane, sulfates (SOx), and soot and metal particles.” 
Now the fun part…
“THERE’S CHEMIKILLS IN MY AIR.”
The quintessential Chemtrailer will claim that there are a host of chemicals being sprayed on us. In my experience, the most common particulates mentioned are aluminum, strontium, and barium. If these were being littered upon us in such volume as to cause detriment to our health, they would be easily detectable in soil and air samples yet, not surprisingly, no proof has been offered from any laboratory to date. Ask the conspiracy theorists to provide one; they can’t and they won’t.
“CONTRAILS DISSIPATE, BUT CHEMTRAILS DON’T.”
Some of the conspiracy theorists don’t want to seem as crazy and so they’ll justify their position by saying that chemtrails stay in the sky for hours while contrails dissipate quickly.