Every few hundred millennia, the Earth undergoes a radical change that sees the planet's magnetic poles flip. The reversal--which would cause all compasses to point "south" rather than what we currently consider north--is long overdue.
A popular doomsday hypothesis posits that, if the reversal were to occur in a single day, all of humanity would be destroyed when the world stops spinning, or perhaps because the magnetic field would cease to protect people from deadly cosmic rays.
But Professor Chen Gengxiong, a researcher with the Institute of Geology and Geophysics at the Chinese Academy of Sciences, says this is rubbish thinking. "People's fears about a magnetic pole reversal stem from our failure to determine the origin of the planet's magnetic field," Chen said.
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