Low-Mass Stars (less than 8 solar masses):
* Red Giant Phase: As the star runs out of hydrogen fuel in its core, it expands and cools, becoming a red giant.
* Planetary Nebula: The outer layers of the star are ejected, creating a beautiful, expanding cloud of gas called a planetary nebula.
* White Dwarf: The core of the star, now made primarily of carbon and oxygen, shrinks and becomes a dense, hot object called a white dwarf. White dwarfs cool over billions of years, eventually becoming black dwarfs, though this process is so slow it has never been observed.
Intermediate-Mass Stars (8-10 solar masses):
* Similar to Low-Mass Stars: The initial stages are similar to low-mass stars, with a red giant phase and a planetary nebula.
* White Dwarf: The core is ultimately compressed into a white dwarf, but it's likely to be richer in heavier elements like oxygen and neon.
High-Mass Stars (greater than 10 solar masses):
* Supergiant Phase: These stars become supergiants, much larger and brighter than red giants.
* Supernova: When the core of a high-mass star collapses, it triggers a violent explosion called a supernova. This explosion blasts off the outer layers of the star and creates heavy elements that are scattered into space.
* Neutron Star: The remaining core, incredibly dense and made mostly of neutrons, becomes a neutron star. Neutron stars are incredibly small and dense, rotating rapidly and emitting powerful electromagnetic radiation.
* Black Hole: If the star is massive enough (more than 20-30 solar masses), the collapse continues beyond the neutron star stage, forming a singularity called a black hole, where gravity is so strong that not even light can escape.
It's important to note:
* This is a simplified explanation, and the details of stellar evolution are complex.
* The exact endpoint also depends on factors like rotation and composition.
* Observations of stellar evolution are ongoing, and astronomers are constantly refining our understanding of how stars live and die.
