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#Magnet...
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Forgive my ignorance but what are the implications of no magnetic field on humans, mammals etc? Does it regulate some crucial biological function(s)?
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#Magnet...