evidence: Chemtrails, short for chemical trails, are what some call the white trails you see left behind as a plane passes overhead. Believers in the chemical aspect of chemtrails say those trails are actually clouds of chemicals used by the government or someother large scale entity for a variety of nefarious purposes from weather modification, to human population control via sterilization, to even mind control. The theories usually claim that normal jet plane output should dissipate quickly so any clouds that do not disappear immediately must be full of additional, undisclosed substances. Chemtrail theories are not only a U.S.-based phenomena—almost 17% of respondents in an international survey noted a belief in the existence of a "secret large scale atmospheric program" to be at least partly true. To address this concern, a group of 77 scientists published a report in the journal of Environmental Research Letters after digging through the supposed evidence of the intent to poison us through chemtrails. These scientists are experts in atmospheric science, including the contributions of aircraft to the atmosphere as well as atmospheric processes like how quickly or uniformly chemicals fall through the air to the ground. Of those 77 scientists, 76 said they found no evidence of a "secret large-scale atmospheric program"—that’s 98.7%. Instead, they found that "the data cited as evidence [for such a program] could be explained through other factors, including well-understood physics and chemistry associated with aircraft." In other words, the evidence pointed to the trails being simply the normally expected result of planes flying through the air.