Strange cacophonous sounds coming from the skies may seem like the prelude to a science-fiction film, but the phenomenon is actually happening throughout the world. At times sounding like trumpet blasts, at others like construction equipment, the noises have been heard for about a decade. Have a listen:
While no one has found an explanation for this mystery, allow me to put forth one: could it be Mother Nature expressing her horror at the way we have been heedlessly neglecting, abusing and exploiting the earth for far too long?
UPDATE: Thanks to Marie for providing this link to other possible explanations.