I'm NOT an authority either ---theories I have seen suggests that there 
are energy rays coming from the sun (at times that are not relected by 
the atmosphere) that penetrate the core of the earth, possibly  causing 
internal heating, electromotive changes, changes in fission/fusion 
processes going on internally, the earth's polarity and even changes in 
the tilt axis (wobble) of the earth (this wobble idea goes back over 
fifty years). Change in earth's polarity is a pretty excepted idea now, 
but how, isn't.
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