The geomagnetic field
Magnets are cool, and that’s a scientifically proven fact. I could make some joke about superconductors couldn’t I? Anyways, the fact is you’re currently clinging to the surface of a giant magnet, sure it’s kinda of glorified by having a nice and friendly covering, but the only reason for that covering and of course you is because we live on a magnet. However it’s not your standard iron bar magnet, instead the magnetic field is explained by something called the dynamo theory. This theory refers not to the solid iron core itself but to the molten iron surrounding this. This liquid iron is an electrically conductive fluid and is in a state of constant (albeit slow) movement due to convection and rotation. As many of you will know a moving current is what is responsible for a magnetic field and it makes no difference whether this in a wire or through a liquid.
So where would we be without the magnetic field? Well it’s thought that the geomagnetic field started up around 3.5 billion years ago, about a billion years after Earth’s formation and around about the same time we get any hint of life in the fossil record. Earth’s magnetic field is what protects us from harmful solar winds and stellar radiation, without it we’d be fried. It’s also the thing that allows us to see auroras. So be thankful for magnetism.