13 April 2012
"It fuses hydrogen to form helium and produces energy that makes the star shine. Then the ashes of that reaction, the helium, fuse together to form carbon and oxygen releasing yet more energy. Then the carbon and oxygen can fuse into more heavier elements: magnesium, sodium etc then silicon and sulfure. And finally iron. When a giant star starts to make iron it is inevitable: it will explosed as a supernova realeasing all those elements into space. Because fusion of iron doesnt produce energy compares to the other fusion it absorb energy. Its a fight between energy and gravity and when giant star starts to produce iron the battle is lost: gravity wins"
Opuss № I