How did Earth avoid a Mars-like fate? Ancient rocks hold clues - Phys.org

Approximately 1,800 miles beneath our feet, swirling liquid iron in the Earth's outer core generates our planet's protective magnetic field. This magnetic field is invisible but is vital for life on Earth's surface because it shields the planet from solar win…

Approximately 1,800 miles beneath our feet, swirling liquid iron in the Earth's outer core generates our planet's protective magnetic field. This magnetic field is invisible but is vital for life on … [+5656 chars]

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