I love science almost as much as I like history--and it's fun to look at the past with science

Iron Age Copper Reveals Earth’s Stronger, Faster Magnetic Field

Slag left over from Iron Age copper smelting shows the Earth’s magnetic field was stronger and more variable than scientists ever imagined.

“This is a very challenging result,” said geomagnetist Luis Silva of the University of Leeds, who was not involved in the new work. “It’s completely outside of anything we thought could be happening in the core.”

The Earth’s magnetic field comes from the movement of molten iron in the core. The field’s strength and structure are constantly changing. But paleomagnetists (scientists who study the history of the Earth’s magnetic field) thought the changes were usually small and slow, fluctuating by about 16 percent over the course of a century.

But a new study of ancient copper mines in southern Israel found that the strength of the magnetic field could double and then fall back down in less than 20 years.

I wonder what effect that magnetic shift could have, oh, on a TARDIS' systems? :)