An Emerging Coherent Picture of Red Supergiant Supernova Explosions

We now know that the bulk of supernovae result from core collapse of red supergiants of modest initial mass, about 8 to 16 solar masses.

However, what happens to stars with somewhat higher masses is rather uncertain, and is related to the puzzling mass distribution of compact remnants that is found. Furthermore, as embarrassing as it is, simulations are so far struggling to produce models that robustly explode. Yet supernovae seem to do it quite easily.

I will address these issues in context, offer some solutions, rule out others, with an emphasis on the observational clues that we can, do, and will try to provide in the near future.