To explain how a black hole forms, we can break it down into a few steps:
1. **Star Formation**: Initially, a black hole starts as a massive star. When a massive star exhausts its nuclear fuel, it can no longer support itself against its own gravity.
2. **Supernova Explosion**: The massive star undergoes a supernova explosion, where its core collapses under immense gravitational forces. This collapse results in a dense core known as a neutron star or in the case of even greater mass, a black hole.
3. **Singularity Formation**: In the case of a black hole, the core continues to collapse, forming a point of infinite density called a singularity. At the singularity, the laws of physics, as we currently understand them, break down.
4. **Event Horizon**: Surrounding the singularity is the event horizon, a boundary beyond which nothing can escape the gravitational pull of the black hole, not even light. Once an object crosses the event horizon, it is effectively trapped within the black hole.
In summary, a black hole forms through the collapse of a massive star's core, leading to the creation of a singularity with infinite density and an event horizon that marks the point of no return for anything falling into the black hole.
