Don't fall for tales of chemtrails
On passenger planes, shadows in the skies, and the problem with letting wild conspiracy theories worm their way into the public mind
An otherwise sensible observer in Central Iowa wants to know why he's seeing dark shadows below the vapor trails visible behind high-flying aircraft, musing aloud (to the Internet) that he thinks something is suspicious about what he's seeing.
■ The phenomenon is easy to explain without the aid of any conspiracy theories. Airplanes quite frequently travel at altitudes of 35,000 feet and even higher. There are always a few overhead. And when wispy cirrus clouds form at lower altitudes (like 25,000 feet, where clouds were overhead all morning in the region), then the contrails formed at 35,000 feet simply cast shadows on the clouds 10,000 feet below them. No need to believe in conspiracy theories over "chemtrails" or any other such nonsense: It's just the Sun and the clouds.
■ There is no shortage of people who are willing and eager to presume that the contrails formed behind high-altitude aircraft are evidence of something sinister. The problem with letting it go on is that self-government depends quite heavily on the judgment of ordinary people.
■ We don't have to be experts, but we do need to know how to evaluate evidence and apply sound reasoning. An unattended gullibility that opens the door to wild conspiracy theories is a dangerous social weakness, because it invites bad actors to introduce malicious misdirection into the public mind.
