I have long suspected that British crop circles were a psychological experiment to see how suggestible humans are: but where are the published papers? The May 16, 2015 Daily Mail reports on dozens of YouTube videos purporting to record strange sounds coming from the sky. So have any of you have first hand experience of this phenomonon?
This guy explains it, but many comments come from people who say they have heard it.
One such occurrence is explained as a city worker grinding flat the edge of a snowplow blade.
ReplyDeleteBoth wind and temperature differences between air near the ground and air aloft can cause strange things to happen to sound propogation outdoors. Just as ham-radio operators use the skywave to bounce signals off the sky, often loud sounds are heard many miles away as the sound near the source is bent skyward and then bent back down elsewhere, causing un-occluded (but low-pass filtered) transmission right over all the vegetation, topography, and buildings that would usually have blocked it.