A closer look

Next time you slice a banana into your oatmeal, respect the fact that you are consuming a low-level antimatter generator. Bananas are rich in potassium, and a tiny fraction of that is the radioactive isotope potassium-40. About once every 75 minutes, a decaying potassium atom spits out a positron—the antimatter equivalent of an electron. Don't panic, though; it immediately annihilates upon hitting an electron, meaning your fruit bowl isn't going to blow up the neighborhood.