The story of Eta Carinae
Eta Carinae has an estimated mass between 90-120 M☉. Unlike our sun which will for a white dwarf and a planetary nebula, Eta Carinae will go out with a bang: A Type II Supernova. This type of supernova is a core collapse supernova. What happens is that the star rapidly burns through it's fuel to offset gravity, forming heavier and heavier elements until it starts making iron. During the nucleosynthisis process, the elements form shells around the core, similar to a Russian nesting doll. This is due to the fact that the specific gravity of the elements in question have a certain density. Since Iron is the heaviest, it sinks all the way to the center of the core.
Iron will fuse, but it will not produce energy when it does, so the star is robbed of the energy it needs to support itself against gravity. Then the core collapses. If the core mass is > 1.4 M☉ (the Chandrasekhar Limit), it will form a black hole. The star is then eaten from the inside out, and the black hole will spin up rapidly, throwing matter out through the poles at very high temperatures and energies (aka the gamma ray burst). To produce gamma rays, the matter must be heated up to billions of Kelvin.
This is a very simplified version of what happens. In case you are wondering, Astronomy is an interest of mine and I have taken a number of courses on it. In fact, Type II Supernovas was the subject of my thesis paper in my writing intensive class which was Astronomy. So, when it comes to Astronomy, you probably could group me in with the boffins.
Biting the hand that feeds IT
