Scientists often warn us about climate change, asteroids or nuclear war. Now scientists have warned of the threat of Earth's magnetic poles reversing. The poles create the magnetic shield around Earth. This protects us from deadly radiation. Life on Earth depends on this shield. The poles could flip in the next thousand years because the molten iron turning around Earth's center is changing direction. This molten iron is like a gigantic electromagnet.
Earth's poles flip roughly every 250,000 years. The last time was 780,000 years ago. The next flip could destroy communications and power grids; deadly solar rays could increase rates of cancer; and climate change could kill many species. A polar flip could even blow Earth's atmosphere away. One scientist dismissed the danger from increased radiation from the poles flipping. He said it would be as harmful as lying on a beach for a day without wearing a hat.