Alright, let's say he dies (Kryptonian cancer).

I'm not going to talk about his soul, so let's assume that the soul isn't an agenda here.

The absorbed sunlight in his body would still power a great deal of his cells, so it would take him some time if not years, to actually die (that is, if Marvel doesn't find a way of saving him again).

His Kryptonian cells would slowly vaporise, so his body wouldn't have the same odor as of a human body. So in short, he would pose as a giant energy container waiting to burst.

Having all this energy in one spot (presuming he is still in one piece), he would be like a dwarf star imploding into a black hole (there are also other possibilities here, turn into a neutron star, a magneter, burst/explode). What would happen to Earth and the human kind?

However, if I'm not correct and his organs really somehow decompose. His body would emit an amount of thermal radiation (an effect known as Hawking radiation), in the end leading to evaporation of his body.

Alright, let's say he dies (Kryptonian cancer).

I'm not going to talk about his soul, so let's assume that the soul isn't an agenda here.

The absorbed sunlight in his body would still power a great deal of his cells, so it would take him some time if not years, to actually die (that is, if DC doesn't find a way of saving him again).

His Kryptonian cells would slowly vaporise, so his body wouldn't have the same odor as of a human body. So in short, he would pose as a giant energy container waiting to burst.

Having all this energy in one spot (presuming he is still in one piece), he would be like a dwarf star imploding into a black hole (there are also other possibilities here, turn into a neutron star, a magneter, burst/explode). What would happen to Earth and the human kind?

However, if I'm not correct and his organs really somehow decompose. His body would emit an amount of thermal radiation (an effect known as Hawking radiation), in the end leading to evaporation of his body.