Gravitational collapse is a process where an astronomical object, such as a star or a cloud of gas, collapses under its own gravity. This phenomenon occurs when the internal pressure that supports the object against gravitational forces is no longer sufficient, leading to a rapid contraction. The result can be the formation of dense objects like black holes or neutron stars. During gravitational collapse, the temperature and pressure at the core increase dramatically, triggering nuclear fusion in some cases. This process is crucial in the life cycle of stars, as it can lead to the birth of new stars from collapsing gas clouds, known as stellar nurseries.