Question: The benifit does the aurora have on the earth?

Joe Reed answered on 10 Nov 2014:

Well, for a start it is beautiful. Red and Green stripes dancing across a black sky.
Secondly, it is partly caused by Earth’s magnetic field. This field protects us from dangerous radiation from space, and stops the charged particles from the sun affecting our electricity, phone and internet networks.

Think of it as a nice reminder that Earth is protecting us.