How does a black hole form?

A black hole forms when a massive star collapses under its own gravity.

When a massive star runs out of fuel, it can no longer produce the energy needed to counteract the force of gravity. The core of the star collapses inward, causing the outer layers to explode in a supernova. If the core is massive enough, it will continue to collapse until it becomes a singularity – a point of infinite density and zero volume. This singularity is surrounded by an event horizon, beyond which nothing, not even light, can escape.

The formation of a black hole is dependent on the mass of the collapsing star. Stars with a mass less than three times that of the sun will form a white dwarf or a neutron star. Stars with a mass between three and twenty times that of the sun will form a black hole through a supernova explosion. Stars with a mass greater than twenty times that of the sun will form a black hole without a supernova, through a process known as pair instability.

Black holes are some of the most mysterious objects in the universe, and their formation is just one aspect of their enigmatic nature. Studying black holes can help us understand the fundamental laws of physics and the nature of space and time.