What do supernovae have to do with heavy elements?

Answer 1

Stars are giant nuclear fusion reactors; with their intense heat and pressure from their immense gravity, they smash hydrogen atoms into helium -- this is called fusion. Helium atoms fuse together to become heavier elements; this is how all of the elements past hydrogen and helium were created (hydrogen was created by the creation of the universe, and it is believed some helium may have been created then, too, but every element past helium owes its existence to the nuclear fusion in stars). This fusion process generates energy for the star (some of the particles making up the atoms that are smashed together are converted into energy during the fusion process), which is why stars continue to burn for so long -- the fusion of atoms generates energy that fuses more atoms together.

As atoms get heavier, however, they are more resistant to fusion and it takes more energy to smash the atoms together. Past iron, atoms require more energy to fuse together than the energy that comes out of the fusion process. The fusion process continues, however, because not all of a star fuses to the same element at the same time (100% of the hydrogen doesn't fuse immediately into helium ... by the time iron atoms are created, there is still plenty of hydrogen still fusing). Because stars are fluid-like plasma, heavier atoms readily sink through to the star's core. It is not a steady process, however ... heavier atoms can sometimes trap lighter ones beneath them. Gradually, though, more and more iron concentrates in the core ... but while fusion is still going on from lighter elements, the iron atoms continue fusing to heavier elements.

Eventually, however, there are too many heavy atoms in a star's core and the fusion fire seizes. The iron atoms collapse and a huge explosion is generated -- depending on the star's size, this can be a nova or supernova (plural novae or supernovae). The energy of this explosion blasts away the dead star's material, including the iron and heavier elements. The heavier elements will tend to form dust and other debris, that may eventually join with clouds of hydrogen to form part of a new solar system.

This is how the elements present in our solar system, and right here on Earth, came to be -- from carbon which makes up most life down to the ultra-heavy atoms like uranium, all of it was created in the fusion of stars and blasted away by novae and supernovae.

Answer 2

Supernovae are responsible for producing and dispersing heavy elements into the universe. During the explosion, the intense conditions allow for nuclear fusion to create heavy elements like gold, uranium, and lead. These elements are then ejected into space, eventually becoming part of new stars, planets, and other celestial bodies.