Alanna Mitchell: Right now on the surface of the planet, it looks like it's just a bar ... two-pole system. But sometimes, Earth doesn't always just have a single magnetic North and South Pole.

Bar magnets and horseshoe magnets are two of ... They will be pushed in opposite directions. If you bring a north pole and a south pole together, they will attract. Earth's core contains liquid ...

Ancient Homo sapiens may have benefited from sunscreen, tailored clothes and the use of caves during the shifting of the ...

British explorer Sir James Clark Ross discovered the magnetic north pole in 1831 in northern Canada, approximately 1,000 ...