How peridodical meteor showers work
Comets consist of water-ice and dust. Whenever they are entering the inner solar system they start"melting", losing some of their mass in form of their comet tail. If it happens that the comet is crossing Earth´s orbit, it leaves a tube of dust on a certain spot of Earth´s orbit. So whenever we are going through that tube we´ll have a meteor shower. That´s why they are so predictable. The last time 109P/Swift–Tuttle was crossing the Earth´s orbit and therefor filling up the tube with fresh dust was in December 1992.
The best time to observe them
Generally said, the best time to observe meteor showers is the second half of the night.This is only true though, if there is no decreasing moon, like we have it this year in 2017. You don´t want to have the moon on the sky when looking for shooting stars. So this year better take the first half of the night. The later the better though.
There´s no need in finding the constellation Perseus, Perseus is indeed the radiant, but shooting stars can be seen all over the sky, in any direction.
The maximum of the Perseids are reached on 13th of August. But the nights right before are or after that date are also fine.
Other known meteor showers
Quadrantids | early January
Alpha Centaurids | early February
Gamma Normids | mid March
Draconids | early October
Leonids | mid-November
Geminids| mid-December
As you can see, there are plenty of meteor showers, so if you miss one, just look out for the next one to come! And don´t forget to make a wish, or 2 ...
source
