> enough mass It's not a question of enough mass. It's a question of being compact enough. There is no minimum mass for a black hole, but the smaller the mass,

> enough mass It's not a question of enough mass. It's a question of being compact enough. There is no minimum mass for a black hole, but the smaller the mass, the smaller the surface area of the horizon (the 2-sphere that the mass has to collapse inside to form the hole).