All I know is that we (the earth) cross the trajectory of two comets, each year at around the same time; In august it is the trajectory of P/Swift-Tuttle, and in december it is the trajectory of Phaeton. Crossing this particle trace results in 'catching' these particles, which, caused by their very high speed (around 35-60 km/sec) and the friction, die down and cause the air along their trajectory to glow.
First time I saw a perseid shower peak was back in 1993 after it was announced in a radio show I incidentally heard. Lol, it was 3am, I sat outside our house and was totally stoned ... Great show 
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