It all starts with a curiosity; Panic at the passing of Halley's Comet

At the beginning of the 20th century, a close approach of Halley's Comet discovered that part of the gases in the comet's tail were toxic gases but in a very low density and if that tail entered or collided with the Earth's atmosphere, those gases would be disintegrated because the chemical compounds when heated can also break down, that is, there was no danger, but panic spread, it was a global panic, it must have been one of the first global panics spread by the media and based on a hoax, perhaps outside the first.

And very strange things were invented and sold, umbrellas for that comet gas, gas masks and a lot of strange gadgets, unfortunately I think there were also suicides.

There was no radio at that time, at that time they were in the press that is, with articles in the written press and that was how panic was transmitted, this teaches us that we do not have to have large media outlets to spread deceptions, you just need people with no knowledge.