The ultimate fate of a star depends on its mass. A massive star ends with a violent explosion called a supernova. The matter ejected in a supernova explosion becomes a glowing supernova remnant.
Toward the end of its life, a massive supergiant star
has a central iron core, surrounded by a shell where
silicon is being fused to iron, surrounded by a shell
where oxygen is being fused, surrounded by a shell where
carbon is being fused, surrounded by a shell where helium is
being fused, surrounded by a shell where hydrogen is
being fused.
