Thanks for adding additional information. I wanted to make clear that I definitely am not saying that it hasn't happened before, or that there isn't any organization that has tested chemicals in the atmosphere. I mentioned Atmospheric geoengineering in the post. I am specifically talking about Contrails that aircraft give off. Most automatically assume that they are "Chem-trails".

Thanks again for the information @modernnomad. This definitely needs to be discussed instead of jumping to conclusions, because you heard another person make a claim.