A planetary magnetic field acts as a shield for space-based radiation that may otherwise interfere with biological processes. There's some really nasty stuff o

A planetary magnetic field acts as a shield for space-based radiation that may otherwise interfere with biological processes. There's some really nasty stuff out there that the earth's field deflects for us : http://en.wikipedia.org/wiki/Earth%27s_magnetic_field#Magnetosphere http://en.wikipedia.org/wiki/Earth%27s_magnetic_field#Magnet...