Earth's 'Magnetic Personality' Much Older Than Previously Thought

Earth's magnetic field has been a life preserver, protecting against relentless solar winds, streams of charged particles rushing from the Sun, that otherwise could strip away the planet's atmosphere and water. "It would be a pretty barren planet without it," said University of Rochester geophysicist John Tarduno. But there has been debate among scientists about when this vital shield generated by Earth's liquid iron core formed. Researchers on Thursday said...

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