So how do you study the Earth's core and magnetic fields when it's protected by 1,800 miles of crust? Easy — you just build your own miniature version in a laboratory, using over 28,000 pounds of molten sodium.

That's exactly what researchers at the University of Maryland have done in a massive experiment that hopes to recreate the magnetic fields generated by the spinning liquid iron in the Earth's outer core. The project has taken ten years and over £1.3 million to come to fruition, but by early next year the team plans to generate its own self-sustaining magnetic field, which can be studied and tested in their lab.

The simulator actually comprises an inner and outer sphere, separated by the molten sodium kept at a piping 105 °C. Since the liquid conducts electricity, it's hoped that the spheres will function like a giant dynamo, producing the same fields as our planet's core. So far all of their attempts have failed, but the researchers are hoping the bigger-is-better approach of their latest attempt will yield a miniature magnetic core they can call their own. [Nature via Slashdot]