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When doom-and-gloom merchants warn us threats to our existence, we usually hear climate change, asteroid strikes or nuclear war. Now scientists have warned the potential threat Earth's magnetic poles flipping upside . The North Pole and South Pole are responsible creating a special barrier Earth that protects us killer radiation from space. All life on Earth depends on this shield. Without it, scientists say solar rays could cause considerable damage. The poles could flip the next thousand years. This is because a rolling layer of liquid iron the earth's crust is changing direction. The revolving currents this molten iron Earth's center act as a gigantic electromagnet.

Historically, Earth's North and South magnetic poles have flipped every 200,000 to 300,000 years. The last time was 780,000 years ago, so the next flip is well overdue. Some scientists say the flip could destroy satellite communications and power grids; that dangerous solar rays would greatly multiply rates cancer; and that climate change could kill billions creatures. Some scientists forewarn that a polar flip could even blow Earth's atmosphere away. However, one scientist dismissed the doom-mongers. He believes that the effects any increase radiation would be as harmful as lying a hot beach a day. He suggested a "floppy hat" would be enough to protect us any increased radiation.

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