This week we've found ourselves attracted by the topic of magnetism; it's what makes it possible to generate and distribute electricity to our homes, or send messages and radio broadcasts over the airwaves; it underpins our ability to see inside the body with technologies like MRI scanners, and thanks to the fact that there's a massive magnetic field surrounding our planet, much of the radiation onslaught from space that would otherwise hit us is fended off, keeping the Earth habitable. That planetary magnetic field also provides us and animals with a way to navigate, and there are even... Like this podcast? Please help us by supporting the Naked Scientists