The collapse of the iron core in a massive star results in a

A star exists due to the balance between two forces:

1. The gravity force that tries to squeeze the stellar material into the smallest and most compact ball possible.

2. The nuclear force, generating heat and pressure in the center of the star that tries to push all the material out.

Now, when the star has occupied all its nuclear fuel, the expansive pressure can no longer counteract gravity and the star suddenly collapses.

When this happens, a supernova is formed, which causes the expulsion of the outer layers of the star by means of powerful shock waves, enriching the space that surrounds it with heavy elements.

So, it can be said that a supernova is the bright, last breath of a star that is at least five times more massive than the Sun.