Ponder this – If you could somehow find a way to get a cast iron frying pan into the sun, within moments the sun would go supernova. Iron would instantly shut down our sun, resulting in a massive supernova.. The most common element in the universe, iron is a stars death sentence. It stops fusion. A star burns hydrogen, when that’s gone it burns helium, turning it into carbon, then it burns the carbon, turning it into oxygen. When the carbon and oxygen atoms fuse, the trouble begins. These elements fuse into iron. Once iron is formed, fusion stops and the star collapses in on itself. Imagine our world suddenly fitting on the end of a pin. That’s a supernova.