Supernove

            fig 1:- A supernova remnant

Imagine a blast in space, a brilliant firework in the core of a star, yes I am talking about supernovae, these are a blast in the core of a dying star, so here a question popups, that why a star which constantly shining for millions of years suddenly go on an explosion, that star exploded because fusion force which is continuously fighting against the force of gravity suddenly stopped, and all the matter started to collapse in the core of star, this all pumps the core of star and it blast off all the matter to the space. Because the star is no longer able to fuse elements to form heavy element. During the explosion that star release energy equivalent to the entire energy released by the sun in his whole life and destroys planets around it. 

So, what will happen to that supernovas, they will become a stellar nursery of the next generation of stars and the universe will recycle all the exploded material and this process of formation of stars will go till and the end of our cosmos