Scientists say the Earth’s magnetic field could be about to flip upside down. During the thousand years it will take for this change to complete, our vital protective magnetic shield will become significantly weaker — with potentially disastrous consequences. Solar winds could destroy our satellite communications and bring the world’s electricity supplies crashing down. Human cancer cases could multiply as unshielded radiation from the sun devastates people’s DNA. Billions of creatures the world over die because their ability to migrate becomes fatally confused by changes in our planet’s magnetic field.