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Earth's magnetic field has flipped hundreds of times; the... | funfact.wiki | funfact.wiki
Earth's magnetic field has flipped hundreds of times; the last reversal was about 780,000 years ago. During reversals the field can weaken to under 10% of today’s strength, letting auroras appear near the equator. Since 1840, Earth’s field has already weakened by about 9%.
  • Earth
  • Magnetic field
  • Aurora
  • Science
  • Physics
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