Magnetic rocks with iron oxide concentrations act as natural chroniclers of Earth's past continental movements. Using small ...

Some inventions are so simple that it’s hard to improve them. The magnetic compass is a great example — a magnetized needle, a bit of cork, and a bowl of water are all you need to start navigating the ...

If shrunken down to micron size, a compass needle could wobble. (Courtesy: iStockphoto/tobias machhaus) A tiny magnetic needle just 10 μm long could be used to create a magnetic-field sensor that – if ...