Here's a breakdown:
* The Trigger: When a massive star runs out of nuclear fuel in its core, the core is primarily made of iron. Iron fusion does not release energy, so the outward pressure from fusion ceases, leading to the core collapsing under its own gravity.
* Collapse Speed: The collapse is incredibly fast, reaching speeds of up to 70,000 km/s (about 25% the speed of light). This is because the core is incredibly dense and the force of gravity is immense.
* Timeframe: The entire collapse process, from the initial instability to the formation of the neutron star or black hole, typically takes only a few milliseconds.
It's important to note that this is a very simplified description. The details of the collapse process are complex and still being studied. However, the incredibly short timeframe is a fundamental aspect of this catastrophic event.
