There is...a growing body of evidence that the Earth's magnetic field is about to disappear, at least for a while. The geological record shows that it flips from time to time, with the south pole becoming the north, and vice versa. On average, such reversals take place every 500,000 years, but there is no discernible pattern. Flips have happened as close together as 50,000 years, though the last one was 780,000 years ago. But, as discussed at the Greenland Space Science Symposium, held in Kangerlussuaq this week, the signs are that another flip is coming soon.