Originally Posted by Robh
Assuming a collision of stars occurred, what is the outcome if two Sun-like stars collide? Supernova?
Think this is right, but stellar physics isn't my strong point.
Supernovas are caused when a large star suffers gravitational collapse after the internal fusion reactions stop producing enough energy to prevent the collapse.
Sun-like stars don't have enough mass to go supernova. They go through a red "giant" phase and finally collapse into a white dwarf.
Now if two of these Sun-like stars collided and merged, the resultant star might be big enough to eventually go supernova, but it wouldn't be the collision that did it. Maybe if they were already white dwarfs before the collision you might get your supernova.