Unlike our geographic north pole, which is in a fixed location, magnetic north wanders. This has been known since it was first measured in 1831 and subsequently mapped drifting slowly from the Canadian Arctic toward Siberia. Since the 1990s, however, this drift has gone from its historic wandering of 0 to 15 kilometers (9 miles) a year to its present speed of 50 to 60 kilometers (37 miles) a year. Satellite data shows that the cause is competition between two magnetic blobs on the edge of the Earth’s outer core. 1990–1999.